Diseases and Disorders





This section includes the diagnostic modalities (imaging and laboratory tests) and algorithms useful to diagnose the following 145 diseases and disorders. It is assumed that the patient has had a detailed history and physical examination before any testing sequence is initiated.


These algorithms are designed to assist clinicians in the evaluation and treatment of patients. They may not apply to all patients with a particular disease or disorder, and they are not intended to replace a clinician’s individual judgment. Please note that specific findings in the patient’s history and physical examination may significantly alter any of the proposed testing sequences.



  • 1.

    Abdominal abscess


  • 2.

    Abdominal aortic aneurysm


  • 3.

    Achalasia


  • 4.

    Acid-base disorders


  • 5.

    Acute kidney injury


  • 6.

    Addison’s disease (adrenal insufficiency)


  • 7.

    Adrenal mass


  • 8.

    Alkaline phosphatase elevation


  • 9.

    ALT/AST elevation


  • 10.

    Amenorrhea, primary


  • 11.

    Amenorrhea, secondary


  • 12.

    Anemia, macrocytic


  • 13.

    Anemia, microcytic


  • 14.

    Antinuclear antibody (ANA)–positive


  • 15.

    Aortic dissection


  • 16.

    Appendicitis


  • 17.

    Ascites


  • 18.

    Avascular necrosis


  • 19.

    Back pain, acute, lumbosacral (LS) area


  • 20.

    Bilirubin elevation


  • 21.

    Bleeding disorder, congenital


  • 22.

    Brain abscess


  • 23.

    Breast mass


  • 24.

    Carcinoid syndrome


  • 25.

    Cardiomegaly on chest radiograph


  • 26.

    Cholangitis


  • 27.

    Cholecystitis


  • 28.

    Cholelithiasis


  • 29.

    Complex regional pain syndrome (reflex sympathetic dystrophy [RSD])


  • 30.

    Constipation


  • 31.

    Creatinine phosphokinase (CPK) elevation


  • 32.

    Cushing’s syndrome


  • 33.

    Deep vein thrombosis (DVT)


  • 34.

    Delayed puberty


  • 35.

    Delirium


  • 36.

    Diarrhea


  • 37.

    Disseminated intravascular coagulation (DIC)


  • 38.

    Diverticulitis


  • 39.

    Dyspepsia


  • 40.

    Dyspnea


  • 41.

    Dysuria


  • 42.

    Ectopic pregnancy


  • 43.

    Edema, lower extremity


  • 44.

    Endocarditis, infective


  • 45.

    Endometriosis


  • 46.

    Epiglottitis


  • 47.

    Fatigue


  • 48.

    Fever of undetermined origin (FUO)


  • 49.

    Galactorrhea


  • 50.

    Genital lesions/ulcers


  • 51.

    Goiter


  • 52.

    Granulomatosis with polyangiitis


  • 53.

    Gynecomastia


  • 54.

    Hearing loss


  • 55.

    Hematochezia


  • 56.

    Hematuria


  • 57.

    Hemochromatosis


  • 58.

    Hemoptysis


  • 59.

    Hepatomegaly


  • 60.

    Hirsutism


  • 61.

    Hyperaldosteronism


  • 62.

    Hypercalcemia


  • 63.

    Hyperkalemia


  • 64.

    Hypermagnesemia


  • 65.

    Hypernatremia


  • 66.

    Hyperphosphatemia


  • 67.

    Hyperthyroidism


  • 68.

    Hypocalcemia


  • 69.

    Hypoglycemia


  • 70.

    Hypogonadism


  • 71.

    Hypokalemia


  • 72.

    Hypomagnesemia


  • 73.

    Hyponatremia


  • 74.

    Hypophosphatemia


  • 75.

    Hypothyroidism


  • 76.

    Immunodeficiency


  • 77.

    Infertility


  • 78.

    Jaundice


  • 79.

    Joint effusion


  • 80.

    Liver function test elevations


  • 81.

    Liver mass


  • 82.

    Lymphadenopathy, generalized


  • 83.

    Malabsorption, suspected


  • 84.

    Meningioma


  • 85.

    Mesenteric ischemia


  • 86.

    Mesothelioma


  • 87.

    Metabolic acidosis


  • 88.

    Metabolic alkalosis


  • 89.

    Microcytosis


  • 90.

    Multiple myeloma


  • 91.

    Multiple sclerosis


  • 92.

    Myalgias


  • 93.

    Muscle weakness


  • 94.

    Neck mass


  • 95.

    Neuropathy


  • 96.

    Neutropenia


  • 97.

    Osteomyelitis


  • 98.

    Pancreatic mass


  • 99.

    Pancreatitis, acute


  • 100.

    Parapharyngeal abscess


  • 101.

    Pelvic mass


  • 102.

    Peripheral arterial disease (PAD)


  • 103.

    Pheochromocytoma


  • 104.

    Pituitary adenoma


  • 105.

    Pleural effusion


  • 106.

    Polyarteritis nodosa


  • 107.

    Polycythemia


  • 108.

    Portal vein thrombosis


  • 109.

    Precocious puberty


  • 110.

    Proteinuria


  • 111.

    Pruritus, generalized


  • 112.

    Pulmonary embolism


  • 113.

    Pulmonary hypertension


  • 114.

    Pulmonary nodule


  • 115.

    Purpura


  • 116.

    Renal artery stenosis


  • 117.

    Renal mass


  • 118.

    Rotator cuff tear


  • 119.

    Sarcoidosis


  • 120.

    Scrotal mass


  • 121.

    Small-bowel obstruction


  • 122.

    Spinal epidural abscess


  • 123.

    Splenomegaly


  • 124.

    Stroke


  • 125.

    Subarachnoid hemorrhage


  • 126.

    Subclavian steal syndrome


  • 127.

    Subdural hematoma


  • 128.

    Superior vena cava syndrome


  • 129.

    Syncope


  • 130.

    Testicular torsion


  • 131.

    Thoracic outlet syndrome


  • 132.

    Thrombocytopenia


  • 133.

    Thrombocytosis


  • 134.

    Thyroid nodule


  • 135.

    Thyroiditis


  • 136.

    Tinnitus


  • 137.

    Transient ischemic attack (TIA)


  • 138.

    Urethral discharge


  • 139.

    Urolithiasis


  • 140.

    Urticaria


  • 141.

    Vaginal discharge


  • 142.

    Vertigo


  • 143.

    Viral hepatitis


  • 144.

    Weight gain


  • 145.

    Weight loss, involuntary



Acronyms





  • A-a: alveolar-arterial



  • AAA: abdominal aortic aneurysm



  • Ab: antibody



  • ABG: arterial blood gas



  • ABI: ankle brachial index



  • ACE: angiotensin-converting enzyme



  • ACTH: adrenocorticotropic hormone



  • ADA: adenosine deaminase



  • AFB: acid-fast bacteria



  • ALT: alanine aminotransferase



  • AMA: antimitochondrial antibody



  • AMP: adenosine monophosphate



  • ANA: antinuclear antibody



  • ASMA: anti–smooth muscle antibody



  • AST: aspartate aminotransferase



  • BNP: B-type natriuretic peptide



  • BUN: blood urea nitrogen



  • c-ANCA: cytoplasmic antineutrophil cytoplasmic antibodies



  • CBC: complete blood cell



  • CDI: Clostridium difficile infection



  • CHF: congestive heart failure



  • CMV: cytomegalovirus



  • CPK: creatinine phosphokinase



  • C&S: culture and sensitivity



  • CSF: cerebrospinal fluid



  • CT: computed tomography



  • DHEAS: dehydroepiandrosterone sulfate



  • DIC: disseminated intravascular coagulation



  • DNA: deoxyribonucleic acid



  • Ds: double strand



  • DS: dehydroepiandrosterone



  • DVT: deep vein thrombosis



  • EB: Epstein-Barr



  • ECG: electrocardiogram



  • ECM: erythema chronicum migrans



  • ELISA: enzyme-linked immunosorbent assay



  • EMG: electromyogram



  • EPS: electrophysiologic



  • ERCP: endoscopic retrograde cholangiopancreatography



  • ESR: erythrocyte sedimentation rate



  • EUS: endoscopy ultrasound



  • FBS: fasting blood sugar



  • FENa: fractional excretion of sodium



  • FNAB: fine-needle aspiration biopsy



  • FSH: follicle-stimulating hormone



  • FUO: fever of undetermined origin



  • GB: gallbladder



  • GFR: glomerular filtration rate



  • GGT: γ-glutamyl transferase



  • GGTP: γ-glutamyl transpeptidase



  • GnRH: gonadotropin-releasing hormone



  • HBsAg: hepatitis B surface antigen



  • hCG: human chorionic gonadotropin



  • HCV: hepatitis C virus



  • HIV: human immunodeficiency virus



  • HSV: herpes simplex virus



  • IEP: immunoelectrophoresis



  • Ig: immunoglobulin



  • IGF: insulin-like growth factor



  • INR: International Normalized Ratio



  • IV: intravenous



  • IVP: intravenous pyelogram



  • K: potassium



  • KOH: potassium hydroxide



  • LDH: lactate dehydrogenase



  • LGV: lymphogranuloma venereum



  • LH: luteinizing hormone



  • LKM: liver kidney microsomal



  • LS: lumbosacral



  • LP: lumbar puncture



  • Na: sodium



  • MIBG: metaiodobenzylguanidine



  • MRA: magnetic resonance angiogram



  • MRCP: magnetic resonance cholangiopancreatography



  • MRDTI: magnetic resonance direct thrombus imaging



  • MRI: magnetic resonance imaging



  • OHP: hydroxyprogesterone



  • O&P: orthotic and prosthetic



  • OR: operating room



  • PA: posteroanterior



  • PAC: plasma aldosterone concentration



  • p-ANCA: perinuclear antineutrophil cytoplasmic antibody



  • PCOS: polycystic ovary syndrome



  • PCR: polymerase chain reaction



  • PCreat: plasma creatinine



  • PE: pulmonary embolism



  • PET: positron emission tomography



  • PFA: platelet function analysis



  • PNa: plasma sodium



  • PPD: purified protein derivative



  • PRA: plasma renin activity



  • PSA: prostate-specific antigen



  • PT: prothrombin time



  • PTH: parathyroid hormone



  • PTT: partial thromboplastin time



  • RAIU: radioactive iodine uptake



  • RBC: red blood cell



  • RDW: red blood cell distribution width



  • RF: rheumatoid factor



  • RNP: ribonucleoprotein



  • r/o: rule out



  • RSD: reflex sympathetic dystrophy



  • SBE: subacute bacterial endocarditis



  • TB: tuberculosis



  • Tc: technetium



  • TEE: transesophageal echocardiogram



  • TIA: transient ischemic attack



  • TIBC: total iron-binding capacity



  • TRH: thyrotropin-releasing hormone



  • TSH: thyroid-stimulating hormone



  • TT: thrombin time



  • TTKG: transtubular potassium gradient



  • UGI: upper gastrointestinal



  • UCreat: urine creatinine



  • UNa: urine sodium



  • UOsmo: urine osmolarity



  • VDRL: venereal disease research laboratories



  • V/Q: ventilation-perfusion



  • WBC: white blood cell






Abdominal Abscess ( Fig. 3.1 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • CT of abdomen with contrast ( Fig. 3.2, A, B )




    FIG. 3.2


    A, CT showing multiple pyogenic abscesses in the liver. B, Computed tomography scan demonstrates a low-attenuation mass in the right lobe of the liver with a prominent halo.

    A, Courtesy Dr. Mukesh Harisinghani, Boston; B, From Kuhn JP, Slovis TL, Haller JO: Caffey’s pediatric diagnostic imaging , vol 2, ed 10, Philadelphia, Mosby, 2004, p. 1473.

Ancillary Tests


  • Ultrasound of abdomen is useful in young women and children

Best Test(s)


  • Gram stain and C&S of abscess

Ancillary Tests


  • CBC count with differential



  • Blood culture × 2



  • ALT, AST



  • BUN, creatinine, glucose




FIG. 3.1


Diagnostic algorithm. ∗Aspiration of hepatic amebic abscess is not indicated unless there is no response to treatment or a pyogenic cause is being considered.





Abdominal Aortic Aneurysm ( Fig. 3.3 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Ultrasound of abdominal aorta ( Fig. 3.4 ) is best initial screening test; CT is more accurate test




    FIG. 3.4


    Ultrasound appearance of an abdominal aortic aneurysm, seen in cross section. Sonography is highly accurate in diagnosing and measuring infrarenal aortic aneurysms.

    Courtesy M. Ellis.

Ancillary Tests


  • CT of abdominal aorta with IV contrast for preoperative imaging and size estimation, and to diagnose perforation/tear



  • Angiography for detailed arterial anatomy before surgery

Best Test(s)


  • None

Ancillary Tests


  • Serum creatinine level before IV contrast




FIG. 3.3


Diagnostic algorithm.





Achalasia ( Fig. 3.5 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Barium swallow with fluoroscopy ( Figs. 3.6, 3.7 )




    FIG. 3.6


    Achalasia. GEJ, Gastroesophageal junction.

    From Weissleder R, Wittenberg J, Harisinghani MG, Chen JW: Primer of diagnostic imaging , ed 5, St. Louis, Mosby, 2011.



    FIG. 3.7


    Radiograph of esophageal achalasia showing the typical tapered (“bird beaked”) appearance at the cardioesophageal junction and retention of food and fluid within a dilated and adynamic esophagus.

    From Talley NJ, Martin CJ: Clinical gastroenterology , ed 2, Sidney, Churchill Livingstone, 2006.

Ancillary Tests


  • Esophageal manometry to confirm diagnosis. It reveals esophageal aperistalsis and abnormal relaxation of lower esophageal sphincter.



  • Upper endoscopy to exclude mechanical obstruction of the esophagus in the region of the lower sphincter

Best Test(s)


  • None

Ancillary Tests


  • CBC



  • Serum albumin for nutritional assessment




FIG. 3.5


Diagnostic algorithm.





Acid-Base Disorders ( Figs. 3.8 and 3.9 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • Chest x-ray

Best Test(s)


  • ABGs

Ancillary Tests


  • Serum electrolytes



  • Urine electrolytes




FIG. 3.8


Determining acid-base status. HCO3 , Bicarbonate; Pa co 2 , partial pressure of arterial carbon dioxide.

From Cameron JL, Cameron AM: Acid-base disorders, Current surgical therapy , ed 12, Philadelphia, Saunders, 2017.



FIG. 3.9


Acid-base nomogram. Shaded areas represent 95% confidence limits of normal respiratory and metabolic compensations for primary disturbances. Points outside shaded areas represent a mixed disorder, assuming absence of laboratory error. HCO3 , Bicarbonate; P co 2 , carbon dioxide partial pressure.

From Vincent JL, Abraham E, Moore FA, et al: Textbook of critical care , ed 6, Philadelphia, Saunders, 2011.





Acute Kidney Injury ( Fig. 3.10 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Renal ultrasound

Ancillary Tests


  • Chest radiograph (r/o pleural effusion, pulmonary/renal syndromes [e.g., Goodpasture, granulomatosis with polyangiitis])



  • CT scan of kidneys without contrast (r/o suspected obstruction)

Best Test(s)


  • Urinalysis

Ancillary Tests


  • Serum osmolality, urine osmolality, urine creatinine



  • Serum electrolytes, calcium, phosphate, uric acid, magnesium



  • Calculate FENa = [UNa/PNa/Ucreat/Pcreat × 100]; FEna <1 in prerenal, >2 in intrinsic renal failure




FIG. 3.10


Diagnostic algorithm.





Addison Disease (Adrenal Insufficiency) ( Fig. 3.11 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • CT or MRI of adrenals with contrast



  • Chest x-ray

Best Test(s)


  • IV cosyntropin test, basal cortisol and serial measurement of cortisol, ACTH level

Ancillary Tests


  • Serum electrolytes (hyponatremia, hyperkalemia)



  • FBS, BUN, creatinine



  • CBC (anemia)




FIG. 3.11


Diagnostic algorithm.





Adrenal Mass ( Fig. 3.12 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • MRI of adrenal gland with contrast

Ancillary Tests


  • CT of adrenal gland with and without contrast ( Fig. 3.13 ) if MRI is contraindicated




    FIG. 3.13


    Adrenal adenoma. On a computed tomography scan, incidental note was made of a small (approximately 1 cm) left adrenal mass ( arrows ). This small size combined with a relatively low-density (dark) center is consistent with a benign adrenal adenoma. Note that any adrenal mass larger than several centimeters should be suggestive of malignancy.

    From Mettler FA: Essentials of radiology , ed 3, Philadelphia, Saunders, 2014.

Best Test(s)


  • Serum electrolytes

Ancillary Tests


  • If symptoms of pheochromocytoma, obtain plasma-free metanephrine level, 24-hour urine collection for metanephrines



  • If cushingoid appearance, obtain overnight dexamethasone suppression test



  • If signs of virilization or feminization, order 24-hour urine for 17-ketosteroids and plasma DHEAS



  • If hypertension is present with associated hypokalemia, evaluate for aldosteronism




FIG. 3.12


Diagnostic algorithm.





Alkaline Phosphatase Elevation ( Fig. 3.14 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • CT of liver

Ancillary Tests


  • Ultrasound of liver



  • Bone scintigraphy (nuclear bone scan) if Paget’s disease of bone is suspected



  • Plain x-rays of abnormal areas identified on bone scan to exclude metastatic disease and confirm Paget’s disease

Best Test(s)


  • GGT

Ancillary Tests


  • Serum calcium, phosphate



  • ALT, AST




FIG. 3.14


Diagnostic algorithm.





ALT/AST Elevation ( Fig. 3.15 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • CT of liver

Ancillary Tests


  • Ultrasound of liver

Best Test(s)


  • None

Ancillary Tests


  • Ferritin/transferrin saturation



  • Viral hepatitis serology



  • GGT, alkaline phosphatase, bilirubin



  • AMA, ASMA, ANA




FIG. 3.15


Diagnostic algorithm.





Amenorrhea, Primary ( Fig. 3.16 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • MRI of pituitary/hypothalamus with gadolinium when hypothalamic/pituitary lesion is suspected

Ancillary Tests


  • Pelvic ultrasound

Best Test(s)


  • Serum hCG



  • FSH



  • Prolactin



  • TSH

Ancillary Tests


  • Progesterone challenge test if initial labs are normal. Test will differentiate between estrogen-deficient state (no bleeding) and estrogen-sufficient state (withdrawal bleeding).



  • Karyotype (r/o Turner syndrome) in patients with primary ovarian insufficiency




FIG. 3.16


Diagnostic algorithm.





Amenorrhea, Secondary ( Fig. 3.17 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • MRI of pituitary/hypothalamus with gadolinium when hypothalamic/pituitary lesion is suspected

Ancillary Tests


  • Pelvic ultrasound



  • CT or MRI of adrenals

Best Test(s)


  • Serum hCG



  • Prolactin



  • FSH



  • Progesterone challenge test to differentiate between estrogen-deficient state (no bleeding) and estrogen-sufficient state (withdrawal bleeding)

Ancillary Tests


  • LH



  • Testosterone, DHEAS



  • TSH




FIG. 3.17


Diagnostic algorithm.





Anemia, Macrocytic ( Fig. 3.18 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • None

Best Test(s)


  • Reticulocyte count

Ancillary Tests


  • Serum B 12 level, RBC folate level



  • ALT, AST, GGTP



  • TSH



  • Direct and indirect antiglobulin test



  • Stool for OB



  • Bone marrow examination




FIG. 3.18


Diagnostic algorithm.





Anemia, Microcytic ( Fig. 3.19 )













Diagnostic Imaging Laboratory Evaluation ( Table 3.1 )
Best Test(s)


  • None

Ancillary Tests


  • None

Best Test(s)


  • Reticulocyte count



  • Stool for occult blood test × 3

Ancillary Tests


  • Ferritin level



  • TIBC, serum iron



  • Hemoglobin electrophoresis



  • Serum lead level




FIG. 3.19


Diagnostic algorithm.


TABLE 3.1

Laboratory Differentiation of Microcystic Anemias


































Abnormality Ferritin Serum IRON TIBC RDW
Iron deficiency
Inflammatory anemia N/↑ N
Sideroblastic anemia N/↑ N N
Thalassemia N/↑ N/↑ N/↓ N/↑

RDW, red cell distribution width; TIBC, total iron-binding capacity.





Antinuclear Antibody (ANA)–Positive ( Fig. 3.20 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • None

Best Test(s)


  • ANA pattern evaluation

Ancillary Tests


  • Anti-Ds DNA Ab



  • Anti-Smith Ab



  • Anti-RNP Ab



  • Anti-SS-A, Anti-SS-B



  • ESR



  • CBC

Box 3.1 summarizes major profiles of autoantibodies in systemic rheumatic diseases.



FIG. 3.20


Diagnostic algorithm.


BOX 3.1

Major Profiles of Autoantibodies in Systemic Rheumatic Diseases

From McPherson RA, Pincus MR: Henry’s clinical diagnosis and management by laboratory methods , ed 23, St. Louis, Elsevier, 2017.




  • 1.

    Systemic lupus erythematosus. Multiple ANAs are frequently seen in systemic lupus erythematosus, often with high levels of anti-dsDNA and antinucleosome antibodies in active disease, together with low complement fractions and high novel biomarker levels, like SIGLEC-1. Distinctiveness of anti-Sm, anti-rRNP, anti-C1q, antinucleosomes, and anti-PCNA.


  • 2.

    Drug-induced lupus. Restriction of ANAs to antihistone and/or antinucleosome antibodies.


  • 3.

    MCTD. Restriction of ANA to U1nRNP (by disease definition).


  • 4.

    Sjögren’s syndrome. Characterized primarily by the presence of antibodies to SS-A/Ro and SS-B/La.


  • 5.

    Systemic sclerosis. Profile consisting of antibodies to Scl-70/topo I, the centromere/kinetochore antigens, anti-RNA polymerases, and other nucleolar antigens such as fibrillarin and Th/To.


  • 6.

    Rheumatoid arthritis. Frequent presence of rheumatoid factor and anticitrullinated proteins (AKA, APF, anti-CCP).


  • 7.

    PM/DM. Presence of Jo-1, Mi-2, and PM-Scl autoantibodies.


  • 8.

    Undifferentiated connective tissue diseases. Autoantibodies, such as anticentromeres, anti-CCP, and anti-dsDNA, may antedate overt clinical disease by many years.



MCTD, mixed connective tissue disease; PM/DM, polymyositis/dermatomyositis.






Aortic Dissection ( Fig. 3.21 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • CT (sensitivity 83%–100%); CT of aorta ( Fig. 3.22 ) is generally readily available and performed as the initial diagnostic modality in suspected aortic dissection




    FIG. 3.22


    Computed tomography scan demonstrating the true lumen and false lumen.

    From Marx JA, Hockberger R, Walls R: Rosen’s emergency medicine , ed 7, Philadelphia, Mosby, 2010.

Ancillary Tests


  • MRI (sensitivity 90%–100%); difficult test for unstable, intubated patient



  • TEE (sensitivity 97%–100%); can also detect aortic insufficiency and pericardial effusion



  • Aortography (sensitivity 80%–90%); involves IV contrast; allows visualization of coronary arteries



  • Chest radiograph ( Fig. 3.23 ), ECG




    FIG. 3.23


    Chest radiograph in acute type A aortic dissection demonstrating a widened mediastinum and enlargement of the ascending and descending aortic shadows ( arrows ).

    From Bonow RO, Mann DL, Zipes DP, et al: Braunwald’s heart disease , ed 9, Philadelphia, Saunders, 2012.

Best Test(s)


  • None

Ancillary Tests


  • CBC



  • BUN, creatinine


FIG. 3.24


Aortic dissection classification.





FIG. 3.21


Diagnostic algorithm.





Appendicitis ( Fig. 3.25 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • CT of appendix ( Fig. 3.26, B ) with oral and IV contrast




    FIG. 3.26


    Appendicitis. A, Ultrasound shows a thickened hypoechoic tubular blind-ended structure in the right iliac fossa. The surrounding fat is hyperechoic. B, Computed tomography shows the thickened, inflamed appendix ( arrow ).

    Courtesy Dr. A McLean, St. Bartholomew’s Hospital, London. From Grainger RG, Allison DJ, Adam A, Dixon AK [eds]: Grainger and Allison’s diagnostic radiology , ed 4, Philadelphia, Churchill Livingstone, 2001.

Ancillary Tests


  • Ultrasound of pelvis (see Fig. 3.26, A ) may be used instead of CT in children and women of reproductive age when CT is unavailable or contraindicated

Best Test(s)


  • CBC with differential



  • Urinalysis

Ancillary Tests


  • Serum pregnancy test in women of reproductive age




FIG. 3.25


Diagnostic algorithm.





Ascites ( Fig. 3.27 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Ultrasound of abdomen/pelvis ( Fig. 3.28 ) is best initial diagnostic test




    FIG. 3.28


    Ascites, ultrasound. Ultrasound is useful for detection of ascites. Simple fluids such as ascites are excellent sound transmission media, reflecting almost no sound waves. As a consequence, they appear quite hypoechoic (black) on ultrasound. This view of the right lower quadrant shows loops of bowel surrounded by fluid. During the ultrasound, the bowel loops would be seen to undergo peristalsis and drift back and forth in the ascitic fluid with patient movement. Ultrasound cannot distinguish the composition of the fluid—ascites, liquid blood, liquid bile, urine, and infectious fluids have a similar appearance, with a few exceptions. Blood may coagulate and form septations within the fluid collection. Infectious fluids also frequently form loculated fluid collections that may be recognized on ultrasound, although the exact composition cannot be determined.

    From Broder JS: Diagnostic imaging for the emergency physician , Philadelphia, Saunders, 2011.

Ancillary Tests


  • CT of abdomen/pelvis

Best Test(s)


  • Calculation of serum-ascites albumin gradient (SAAG) ( Table 3.2 ); analysis of paracentesis fluid for LDH, glucose, albumin, total protein

Ancillary Tests


  • Paracentesis fluid analysis for cell count and differential, Gram stain, AFB stain, bacterial and fungal cultures, amylase ( Table 3.3 )



  • CBC, ALT, AST, BUN, creatinine




FIG. 3.27


Diagnostic algorithm.


TABLE 3.2

Using the Serum-Ascites Albumin Gradient and the Ascites Total Protein Level to Diagnose the Cause of Ascites

From Goldman L, Schafer AI: Goldman’s Cecil medicine , ed 24, Philadelphia, Saunders, Elsevier, 2012.




















Condition Serum-Ascites Albumin Gradient Ascites Total Protein Level
Cirrhosis High Low
Malignant ascites Low High
Cardiac ascites High High

High is greater than 1.1 g/dL; low is less than 1.1 g/dL.


High is greater than 2.5 g/dL; low is less than 2.5 g/dL.



TABLE 3.3

Characteristics of Ascitic Fluid in Various Conditions

From Ferri F: Practical guide to the care of the medical patient , ed 8, St. Louis, Mosby, Elsevier, 2010.










































































Biology Appearance Total Protein (g/dL) LDH (IU) Specific Gravity Glucose (mg/dL) WBCs/mm 3 RBCs/MM 3 Amylase
Neoplasm Bloody
Clear
Chylous
>2.0 >200 Variable <60 ↑↑
Cirrhosis Straw colored <2.5 <200 <1.016 <60
Nephrosis Straw colored <2.5 <200 <1.016 >60
CHF Straw colored <2.5 <200 <1.016 >60
Pyogenic Turbid >2.5 >200 >1.016 >60 ↑↑ PMNs
Pancreatic Hemorrhagic
Turbid
Chylous
>2.5 >200 Variable >60 Variable Variable ↑↑

CHF, congestive heart failure; LDH, lactate dehydrogenase; PMN, polymorphonuclear neutrophil; RBC, red blood cell; WBC, white blood cell.





Avascular Necrosis ( Fig. 3.29 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • MRI of affected joint ( Fig. 3.30, A )




    FIG. 3.30


    Aseptic necrosis of the hip in a renal transplant recipient. A, Early changes consisting of low-intensity oblique lines are noted by magnetic resonance imaging. B, Late changes of avascular necrosis by radiograph show narrowing of the hip joint space, sclerosis of the femoral head, and flattening of the left femoral head.

    From Johnson RJ, Feehally J: Comprehensive clinical nephrology , ed 2, St. Louis, Mosby, 2000.

Ancillary Tests


  • Bone scan if MRI is contraindicated or not readily available



  • Plain films of affected joint usually insensitive in early course but more evident as disease progresses ( Fig. 3.30, B )

Best Test(s)


  • None

Ancillary Tests


  • CBC with differential



  • ESR (nonspecific)



  • ANA




FIG. 3.29


Diagnostic algorithm.





Back Pain, Acute, Lumbosacral (LS) Area ( Fig. 3.31 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • MRI of LS spine

Ancillary Tests


  • Plain radiographs of spine



  • CT scan of LS spine if MRI is contraindicated



  • Ultrasound or CT of abdominal aorta if AAA is suspected

Best Test(s)


  • None

Ancillary Tests


  • CBC



  • ESR



  • Urinalysis




FIG. 3.31


Diagnostic algorithm.





Bilirubin Elevation ( Fig. 3.32 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • Ultrasound of abdomen



  • CT of abdomen



  • ERCP



  • MRCP

Best Test(s)


  • Bilirubin fractionation

Ancillary Tests


  • Alkaline phosphatase



  • ALT, AST, PT (INR)



  • CBC



  • Antiglobulin test, haptoglobin



  • Viral hepatitis panel



  • ANA



  • LDH




FIG. 3.32


Diagnostic algorithm.





Bleeding Disorder, Congenital ( Fig. 3.33 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • None

Best Test(s)


  • PT (INR), PTT

Ancillary Tests


  • Platelet count



  • Clot stability test



  • TT



  • Factor VIII, IX assay



  • PFA 100 assay



  • Fibrinogen level



  • Factor II, V, X, XIII




FIG. 3.33


Diagnostic algorithm.





Brain Abscess ( Fig. 3.34 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • MRI of brain with contrast

Ancillary Tests


  • CT scan with IV contrast ( Fig. 3.35 ) if MRI is contraindicated




    FIG. 3.35


    Computed tomography (CT) with contrast. A, Note the large, wall-enhancing abscess in the left frontal lobe causing a shift of the brain to the right. B, The patient had no neurologic signs until just before the CT scan because the abscess is located in the frontal lobe, a “silent” area of the brain.

    Kliegman RM, Stanton B, St. Geme J, et al: Nelson textbook of pediatrics , ed 19, Philadelphia, Saunders, 2011.



  • Echocardiography if bacterial endocarditis is suspected source of septic emboli to brain

Best Test(s)


  • CBC with differential

Ancillary Tests


  • Blood cultures (10% positive)



  • ESR




FIG. 3.34


Diagnostic algorithm.





Breast Mass ( Fig. 3.36 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Diagnostic mammogram ( Fig. 3.38, A )




    FIG. 3.38


    Mammogram and ultrasound findings of breast disease. A, A stellate mass in the breast. The combination of a density with spiculated borders and distortion of surrounding breast architecture suggests a malignancy. B, Clustered microcalcifications. Fine, pleomorphic, and linear calcifications that cluster together suggest the diagnosis of ductal carcinoma in situ. C, An ultrasound image of breast cancer. The mass is solid, containing internal echoes and displaying an irregular border. Most malignant lesions are taller than they are wide.

    From Townsend CM, Beauchamp RD, Evers BM, Mattox KL [eds]: Sabiston textbook of surgery , ed 17, Philadelphia, Saunders, 2004.



  • Breast ultrasound ( Fig. 3.38, B )

Ancillary Tests


  • MRI of breast in selected cases (e.g., prior breast cancer, breast implant)

Best Test(s)


  • Breast biopsy of suspicious lesion ( Fig. 3.37 )




    FIG. 3.37


    An ultrasound image shows a nonpalpable superficial breast mass (A). A second image shows the linear echogenic biopsy needle penetrating the mass (B).

    From Mettler FA: Essentials of radiology , ed 3, Philadelphia, Saunders, 2014.

Ancillary Tests


  • Aspiration and cytologic examination of breast cyst




FIG. 3.36


Diagnostic algorithm.





Carcinoid Syndrome ( Fig. 3.39 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Radionuclide iodine-113–labeled somatostatin scan (123-ISS) (octreotide scan) ( Fig. 3.40 )




    FIG. 3.40


    Octreoscan illustrating uptake pattern in liver metastases from a small-bowel carcinoid.

    From Cameron JL, Cameron AM: Small-bowel carcinoid/neuroendocrine tumors, Current surgical therapy , ed 10, Philadelphia, Saunders, 2011.



  • CT scan of abdomen, pelvis, and chest with oral and IV contrast to localize tumor and detect metastases

Ancillary Tests


  • Echocardiogram or cardiac MRI in suspected cardiac carcinoid

Best Test(s)


  • 24-hour urine for HIAA

Ancillary Tests


  • ALT, AST



  • Serum electrolytes, BUN, creatinine



  • Alkaline phosphatase



  • Endoscopic biopsy of gastric carcinoids




FIG. 3.39


Diagnostic algorithm.





Cardiomegaly on Chest Radiograph ( Fig. 3.41 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Echocardiogram ( Fig. 3.42 )




    FIG. 3.42


    Echocardiogram shows a large pericardial effusion ( arrows ). D, Diaphragmatic pericardium; V, ventricle.

    From Sellke FW, del Nido PJ, Swanson SJ: Sabiston & Spencer surgery of the chest , ed 9, Philadelphia, Elsevier, 2016.

Ancillary Tests


  • Cardiac MRI if pericardial thickening or mass



  • ECG

Best Test(s)


  • None

Ancillary Tests


  • TSH



  • Creatinine, ALT



  • ESR



  • Urinalysis


FIG. 3.43


Chest radiograph from a patient with a pericardial effusion showing a typical “water bottle” heart.

From Crawford MH, DiMarco JP, Paulus WJ [eds]: Cardiology , ed 2, St. Louis, Mosby, 2004.





FIG. 3.41


Diagnostic algorithm.





Cholangitis ( Fig. 3.44 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Ultrasound of abdomen is preferred initial screening test; allows visualization of gallbladder and bile ducts to differentiate extrahepatic obstruction from intrahepatic cholestasis; insensitive but specific for visualization of common duct stones

Ancillary Tests


  • CT of abdomen ( Fig. 3.45 ) is less accurate for gallstones but more sensitive than ultrasound for visualization of bilirubin distal part of common bile duct; also allows better definition of neoplasm




    FIG. 3.45


    Ascending cholangitis, dilated bile ducts, computed tomography with intravenous contrast. Obstruction of the biliary ducts can lead to devastating ascending infection—cholangitis. This is largely a clinical diagnosis, because classic imaging findings such as pneumobilia can lag behind clinical deterioration. Fever, jaundice, abdominal pain, and altered mental status should prompt immediate antibiotic therapy and surgical consultation, regardless of imaging findings. A, C, Axial images. B, D, Close-ups from A and C, respectively. This patient with a known pancreatic mass and a previously placed biliary stent presented with right upper quadrant abdominal pain. She became febrile during her emergency department stay. Her scan shows biliary ductal dilatation, suggesting obstruction of her stent. In addition to antibiotic therapy, a procedure to relieve obstruction is needed. Her blood cultures subsequently grew Escherichia coli , consistent with ascending cholangitis.

    From Broder JS: Diagnostic imaging for the emergency physician , Philadelphia, Saunders, 2011.



  • MRCP or ERCP indicated if CT or ultrasound is inconclusive; MRCP can be used to visualize common bile duct and level of obstruction; ERCP can also be used to confirm obstruction and its level; it also allows collection of specimen for culture and cytologic examination and provides relief of obstruction

Best Test(s)


  • CBC with differential



  • Blood culture × 2

Ancillary Tests


  • Serum amylase, lipase



  • ALT, AST, alkaline phosphatase




FIG. 3.44


Diagnostic algorithm.





Cholecystitis ( Fig. 3.46 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Ultrasound of gallbladder ( Fig. 3.47 )




    FIG. 3.47


    Acute calculous cholecystitis. A, Gallstone with posterior shadowing and anterior wall thickening (measured to be 9.1 mm with the calipers; stars indicate the ends of the calipers measuring the gallbladder wall). B, Acute cholecystitis with pericholecystic fluid ( arrow ). A gallstone was impacted in the gallbladder neck.

    From Adams JG et al: Emergency medicine: clinical essentials , ed 2, Philadelphia, Elsevier, 2013.

Ancillary Tests


  • Nuclear imaging (HIDA) scan ( Fig. 3.48 ) is useful for suspected acalculous cholecystitis or when ultrasound is inconclusive




    FIG. 3.48


    Acute cholecystitis. Following the intravenous administration of 200 MBq (5 mCi) of Tc-99m–HIDA and a stimulus of cholecystokinin, the region of the liver and gallbladder is imaged. Intrahepatic bile ducts are visualized, as is excretion through the common duct into the small bowel. The gallbladder is not seen. This patient had gallstones demonstrated by ultrasound and confirmed at surgery. The pathologic diagnosis was acute cholecystitis.

    From Grainger RG, Allison DJ, Adam A, Dixon AK [eds]: Grainger and Allison’s diagnostic radiology , ed 4, Philadelphia, Churchill Livingstone, 2001.



  • CT of abdomen useful in suspected abscess, neoplasm, or pancreatitis

Best Test(s)


  • CBC with differential

Ancillary Tests


  • Alkaline phosphatase



  • ALT, AST, bilirubin



  • Serum amylase




FIG. 3.46


Diagnostic algorithm.





Cholelithiasis ( Fig. 3.49 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Ultrasound of gallbladder ( Fig. 3.50 ) will detect stones and biliary sludge (sensitivity 95%, specificity 90%)




    FIG. 3.50


    Examples of cholelithiasis (A to D) depicting the different appearances of gallstones ( arrows ).

    From Adams JG et al: Emergency medicine: clinical essentials , ed 2, Philadelphia, Elsevier, 2013.

Ancillary Tests


  • CT of abdomen useful in patients with inconclusive ultrasound to r/o neoplasm or abscess mimicking cholelithiasis; however, it is less sensitive than ultrasound for cholelithiasis

Best Test(s)


  • None

Ancillary Tests


  • Lipid panel



  • ALT, alkaline phosphatase, bilirubin



  • CBC, amylase




FIG. 3.49


Diagnostic algorithm.





Complex Regional Pain Syndrome (Reflex Sympathetic Dystrophy [RSD]) ( Fig. 3.51 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • Three-phase radionuclide bone scan ( Fig. 3.52 )




    FIG. 3.52


    Reflex sympathetic dystrophy in a patient with a history of right wrist fracture. Three-phase bone scintography shows increased tracer delivery to the right distal upper extremity diffusely (arrow) on flow (top) and blood pool (middle) images. Delayed images (bottom) reveal diffuse abnormal uptake in the wrist (lower arrow) and increased activity in a juxtaarticular distribution (upper arrows) .

    From DeLee D, Drez D: DeLee and Drez’s orthropaedic sports medicine , 2 ed. Philadelphia, 2003, Saunders.



  • Radiograph of affected limb (r/o other cause of patient’s symptoms)

Best Test(s)


  • None

Ancillary Tests


  • CBC, ESR



  • ANA



  • FBS




FIG. 3.51


Diagnostic algorithm.





Constipation ( Fig. 3.53 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • CT colonography if patient refuses colonoscopy

Ancillary Tests


  • Consider barium enema (if patient refuses colonoscopy or CT colonography)



  • Pelvic ultrasound



  • GI motility study

Best Test(s)


  • None

Ancillary Tests


  • CBC



  • TSH



  • Serum calcium, electrolytes, BUN, creatinine, ALT




FIG. 3.53


Diagnostic algorithm.





Creatinine Phosphokinase (CPK) Elevation ( Fig. 3.54 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • None

Best Test(s)


  • CPK fractionation

Ancillary Tests


  • Serum troponin levels



  • CBC, electrolytes, BUN, ALT, creatinine



  • TSH, urinalysis



  • ANA



  • ESR, CRP




FIG. 3.54


Diagnostic algorithm.





Cushing’s Syndrome ( Fig. 3.56 , Table 3.4 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • MRI or CT of adrenals with IV contrast in suspected adrenal Cushing’s syndrome



  • MRI of brain ( Fig. 3.55 ) with gadolinium in suspected pituitary Cushing’s syndrome




    FIG. 3.55


    A, Magnetic resonance imaging (MRI) scan of pituitary demonstrates the typical appearance of a pituitary microadenoma. A hypodense lesion is seen in the right side of the gland ( arrow ), with deviation of the pituitary stalk away from the lesion. After a biochemical diagnosis of Cushing’s disease, this patient was cured by transsphenoidal hypophysectomy. B, MRI scan of the pituitary gland demonstrates a large macroadenoma ( arrow ) in a patient with Cushing’s disease. In contrast to smaller tumors, large macroadenomas are invariably invasive and recur after surgery.

    From Melmed S, Polonsky K, Larsen P, Kronenberg H: Williams textbook of endocrinology , ed 12, Philadelphia, Saunders, 2011.

Ancillary Tests


  • CT of chest in patients with ectopic ACTH production to r/o neoplasm of lung, kidney, or pancreas

Best Test(s)


  • 24-h urine-free cortisol (gold standard for diagnosis, a 3-fold to 4-fold increase above normal confirms diagnosis)



  • Overnight dexamethasone suppression test



  • Plasma cortisol



  • Late-night salivary cortisol measurement

Ancillary Tests


  • Electrolytes, creatinine, glucose



  • CRH plus desmopressin stimulation test


Imaging studies are indicated only after biochemical documentation of hypercortisolism.




FIG. 3.56


Diagnostic algorithm.


TABLE 3.4

Tests Used in the Differential Diagnosis of Cushing’s Syndrome

From Goldman L, Schafer AI: Goldman’s Cecil medicine , ed 24, Philadelphia, Saunders, Elsevier, 2012.












































Etiology Overnight Dexamethasone Suppression Test Plasma ACTH Low-Dose Dexamethasone High-Dose Dexamethasone Corticotropin-Releasing Hormone Stimulation of Acth Petrosal-to-Peripheral Acth Ratio
Normal Suppression Normal Suppression Normal
Pituitary No suppression Normal or high No suppression Suppression Normal or increased >2
Ectopic No suppression High or normal No suppression No suppression No response <1.5
Adrenal No suppression Low No suppression No suppression No response

ACTH, adrenocorticotropic hormone.

Classic responses are indicated. Certain cases of ectopic ACTH production are suppressed by high-dose dexamethasone or are stimulated by corticotropin-releasing hormone. In these cases, petrosal sinus sampling is the most reliable method for distinguishing pituitary and ectopic sources of ACTH.






Deep Vein Thrombosis (DVT) ( Fig. 3.57 , Table 3.5 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Compressive duplex ultrasonography of affected extremity ( Fig. 3.58 )




    FIG. 3.58


    Doppler ultrasound appearance of deep vein thrombosis. The superficial femoral vein is filled with echogenic material representing thrombus, and no flow can be identified in the vein on Doppler evaluation. Flow can be identified in the adjacent artery on color Doppler evaluation ( arrows ).

    From Crawford MH, DiMarco JP, Paulus WJ [eds]: Cardiology , ed 2, St. Louis, Mosby, 2004.

Ancillary Tests


  • Contrast venography; “gold standard” but invasive and painful



  • MRDTI; very accurate and noninvasive but limited by cost and availability

Best Test(s)


  • d -dimer assay by ELISA

Ancillary Tests


  • PT, PTT, platelet count



  • Coagulopathy workup (e.g., protein C, protein S, antithrombin III, factor V Leiden, lupus anticoagulant) in patients with suspected coagulopathy




FIG. 3.57


Integrated strategy for diagnosis of deep venous thrombosis (DVT) using clinical probability assessment, measurement of d -dimer, and ultrasonography of the legs as primary diagnostic tests. If the clinical probability is low (i.e., DVT is unlikely and d -dimer is negative), no further investigations are required. If d -dimer is positive, proceed to ultrasonography of the legs; then either treat the DVT or stop the investigations. If the clinical probability is high (i.e., DVT is likely), d -dimer measurement need not be carried out; proceed directly to ultrasonography of legs. If negative, options are to repeat ultrasound in 1 week or, in some cases with high suspicion for DVT, to perform an ascending venogram.

From Vincent JL, Abraham E, Moore FA, et al: Textbook of critical care , ed 6, Philadelphia, Saunders, 2011.


TABLE 3.5

Wells’ Clinical Assessment Model for the Pretest Probability of Lower-Extremity Deep Vein Thrombosis

From Crawford MH, DiMarco JP, Paulus WJ [eds]: Cardiology , ed 2, St. Louis, Mosby, 2004.


































SCORE
Active cancer (treatment ongoing or within previous 6 months or palliative) 1
Paralysis, paresis, or recent plaster immobilization of the lower extremities 1
Recently bedridden >3 days or major surgery within 4 weeks 1
Localized tenderness along the distribution of the deep venous system 1
Entire leg swollen 1
Calf swelling >3 cm asymptomatic side (measured 10 cm below tibial tuberosity) 1
Pitting edema confined to the symptomatic leg 1
Collateral superficial veins (nonvaricose) 1
Alternative diagnosis as likely or greater than likelihood of DVT −2

DVT, deep vein thrombosis.

In patients with symptoms in both legs, the more symptomatic leg is used. Pretest probability is calculated as the total score: high >3; moderate 1 or 2; low <0.





Delayed Puberty ( Fig. 3.59 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • MRI of pituitary with gadolinium



  • Pelvic ultrasound (females)



  • Bone age (hand and wrist film)

Best Test(s)


  • FSH, LH

Ancillary Tests


  • Prolactin



  • Serum free testosterone



  • GnRH



  • Chromosomal karyotyping



  • IGF-1




FIG. 3.59


Diagnostic algorithm.





Delirium ( Fig. 3.60 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • CT of head without contrast to r/o subdural hematoma, hemorrhage in patients with focal neurologic deficits on examination

Ancillary Tests


  • Chest x-ray (rule out pneumonia)

Best Test(s)


  • Variable with clinical suspicion and physical examination (e.g., toxicologic screen in suspected drug abuse, CSF examination in suspected encephalitis or meningitis, CBC with differential, urinalysis, urine culture in suspected infectious process)

Ancillary Tests


  • Blood culture × 2



  • ALT, AST



  • TSH, B 12 level



  • BUN, creatinine, urinalysis



  • ABGs or pulse oximetry



  • Serum electrolytes, glucose, calcium, phosphate, magnesium




FIG. 3.60


Diagnostic algorithm.





Diarrhea ( Fig. 3.61 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • Small-bowel series if malabsorption is suspected



  • Capsule endoscopy

Best Test(s)


  • Serum electrolytes, BUN, creatinine



  • Stool Na + , K +



  • CBC with differential



  • Stool for Clostridium difficile toxin assay

Ancillary Tests


  • Stool for O&P



  • Stool for occult blood × 3



  • Stool Sudan stain (in malabsorption, mucosal disease, pancreatic insufficiency, bile salt insufficiency)



  • Stool osmolality (stool [Na plus K]) × 2



  • ALT, AST



  • TSH, free T 4



  • IgA anti-tTG antibody to screen for celiac disease



  • Albumin, total protein, glucose



  • Stool cultures for Escherichia coli, Shigella, Salmonella, Yersinia, Campylobacter, Entamoeba histolytica



  • Antigliadin IgA antibody, endomysial IgA antibody



  • Colon biopsy




FIG. 3.61


Diagnostic algorithm.





Disseminated Intravascular Coagulation (DIC) ( Fig. 3.62 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • Chest radiograph to exclude infectious process in patients presenting with pulmonary symptoms

Best Test(s)


  • PT (INR), PTT, fibrin degradation products (FDPs), d -dimer, TT



  • Fibrinogen level, platelet count



  • CBC, peripheral blood smear

Ancillary Tests


  • ALT, AST to r/o liver disease



  • Factor V, VIII




FIG. 3.62


Diagnostic algorithm.





Diverticulitis ( Fig. 3.63 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • CT scan of abdomen and pelvis with oral and IV contrast ( Fig. 3.64 ); typical findings are thickening of bowel wall, pericolonic fat stranding, abscess formation




    FIG. 3.64


    Axial and coronal postcontrast images show a redundant sigmoid looping to the right with thick wall and pericolonic fat stranding ( arrow ) suggestive of diverticulitis.

    From Fielding JR, Brown DL, Thurmond AS: Gynecologic imaging , Philadelphia, Saunders, 2011.

Ancillary Tests


  • None

Best Test(s)


  • CBC with differential



  • Blood culture × 2

Ancillary Tests


  • Urinalysis, urine culture



  • ALT, creatinine, BUN, electrolytes, amylase



  • Serum pregnancy test in reproductive-age women




FIG. 3.63


Diagnostic algorithm.





Dyspepsia ( Fig. 3.65 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Endoscopy

Ancillary Tests


  • UGI series if patient refuses endoscopy



  • Chest radiograph



  • Ultrasound of neck

Best Test(s)


  • H. pylori stool antigen or breath test

Ancillary Tests


  • CBC




FIG. 3.65


Diagnostic algorithm.





Dyspnea ( Fig. 3.66 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Chest radiograph

Ancillary Tests


  • ECG



  • Echocardiogram



  • PFTs



  • CT of chest to rule out pulmonary embolism

Best Test(s)


  • CBC (r/o anemia, infection)



  • d -dimer

Ancillary Tests


  • ABGs or pulse oximetry (r/o PE)



  • TSH



  • Serum electrolytes, BUN, creatinine



  • BNP




FIG. 3.66


Diagnostic algorithm.





Dysuria ( Fig. 3.67 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • None

Ancillary Tests


  • Pelvic ultrasound

Best Test(s)


  • Urinalysis, urine C&S ( Box 3.2 )



    BOX 3.2

    Patient Groups in Which Urine Culture Is Indicated

    From Marx JA, Hockberger R, Walls R: Rosen’s emergency medicine, ed 8, Philadelphia, Saunders, 2014.





    • Children



    • Adult men



    • Immunocompromised patients



    • Patients with “treatment failure” (i.e., with persistent urinary symptoms despite recently completed course of antibiotics)



    • Patients with duration of symptoms more than 4 to 6 days



    • Elderly patients at risk for bacteremia



    • Ill-appearing patients with signs and symptoms suggestive of pyelonephritis or bacteremia



    • Pregnant women



    • Patients with known chronic or recurrent renal infection



    • Patients with known anatomic urologic abnormalities



    • Patients in whom urinary tract obstruction is suspected (e.g., stones, benign prostatic hypertrophy)



    • Patients with serious medical diseases, including diabetes mellitus, sickle cell anemia, cancer, and other debilitating diseases



    • Patients with alcoholism or drug dependence



    • Recently hospitalized patients



    • Patients taking antibiotics



    • Patients who recently have undergone urinary tract instrumentation (e.g., cystoscopy, catheterization)





  • PCR assay for Chlamydiae or Neisseria gonorrhoeae

Ancillary Tests


  • summarizes patients in which urine culture is indicated



  • VDRL, HIV



  • Gram stain and C&S of urethral discharge




FIG. 3.67


Diagnostic algorithm.





Ectopic Pregnancy ( Fig. 3.68 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Transvaginal ultrasound ( Fig. 3.69 )




    FIG. 3.69


    Ultrasound scan showing ectopic pregnancy. A, Transabdominal scan showing empty uterus with a complex mass in the right adnexa measuring 21 × 22 mm. B, Transvaginal scan showing absence of gestational sac in the uterus and decidual reaction with marked endometrial thickening. There is free fluid in the pouch of Douglas (blood will be found there in ruptured ectopic pregnancy).

    From Greer IA, Cameron IT, Kitchener HC, Prentice A: Mosby’s color atlas and text of obstetrics and gynecology , London, Harcourt, 2000.

Ancillary Tests


  • CT of abdomen and pelvis with IV contrast ( Fig. 3.70 ) in ruptured ectopic pregnancy with confirmed fetal loss




    FIG. 3.70


    Ruptured ectopic pregnancy: computed tomography (CT) with intravenous and oral contrast viewed on soft-tissue windows. This 20-year-old woman underwent abdominal CT for suspected appendicitis, given a history of right lower abdominal pain. A urine pregnancy test was not obtained before CT scan. A and B, Free fluid representing hemoperitoneum is seen in the pelvis and extending to a perihepatic subdiaphragmatic location (compare this dark fluid density with the urine-filled bladder). A ringlike enhancing structure is seen in the right pelvis. A bright blush of contrast is seen that is not contained within vessels or bowel—this represents active bleeding from a ruptured ectopic pregnancy. It is bright because of active extravasation of contrast, whereas blood that accumulated before contrast injection is dark. At laparotomy, 2 L of hemoperitoneum were evacuated, and active bleeding from the right fallopian tube was noted. A 4-cm structure that looked like a gestational sac with a possible tiny embryo within it was also found free in the abdomen.

    From Broder JS: Diagnostic imaging for the emergency physician , Philadelphia, Saunders, 2011.

Best Test(s)


  • Serum hCG (quantitative)

Ancillary Tests


  • Serum progesterone (decreased production in ectopic pregnancy)



  • CBC



  • Urinalysis




FIG. 3.68


Diagnostic algorithm.





Edema, Lower Extremity ( Fig. 3.71 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Doppler ultrasound in suspected DVT

Ancillary Tests


  • Plain x-ray films of extremities in patients with history of musculoskeletal trauma (r/o fracture)



  • Echocardiogram (r/o CHF, valvulopathy)



  • CT and/or ultrasound of pelvis

Best Test(s)


  • None

Ancillary Tests


  • d -dimer by ELISA when DVT is suspected



  • Creatinine, ALT, albumin



  • TSH



  • Urinalysis



  • 24-hour urine protein to r/o nephrotic syndrome if urinalysis reveals proteinuria



  • BNP



  • Box 3.3 summarizes causes of lower- extremity edema



    BOX 3.3

    Causes of Peripheral Edema

    From Vincent JL, Abraham E, Moore FA, et al: Textbook of critical care , ed 6, Philadelphia, Saunders, 2011.





    • Heart failure



    • Hypoproteinemia



    • Liver cirrhosis



    • Nephrotic syndrome



    • Lymphedema



    • Malnutrition



    • Gravitational edema






FIG. 3.71


Diagnostic algorithm.





Endocarditis, Infective ( Fig. 3.72 , Table 3.6 )













Diagnostic Imaging Laboratory Evaluation
Best Test(s)


  • Transesophageal echocardiogram (TEE), ( Fig. 3.73 )




    FIG. 3.73


    A transesophageal 120-degree view in a patient with prosthetic aortic valve endocarditis and aortic root abscess. The posterior aortic root wall is thickened with lucent areas of liquefaction (abscess formation) from infection within the wall ( arrowheads ). The infection can extend down the intervalvular fibrosa to involve the anterior mitral valve leaflet ( AMVL ). Multiple small echo densities are attached to the prosthetic aortic valve ( PAV ) sewing ring, which are representative of prosthetic valve vegetations. LV , Left ventricle.

    From Boxt LM, Abbara S: The requisites: cardiac imaging , ed 4, Philadelphia, Elsevier, 2016.

Ancillary Tests


  • Transthoracic echocardiography if TEE is not readily available or patient is uncooperative

Best Test(s)


  • Blood culture × 3

Ancillary Tests


  • CBC with differential



  • ESR (nonspecific)



  • Urinalysis




FIG. 3.72


Diagnostic algorithm.


TABLE 3.6

Modified Duke Criteria for the Diagnosis of Infective Endocarditis

From Ballinger A: Kumar & Clark’s essentials of clinical medicine , ed 5, Edinburgh, Saunders, 2012.



























Major criteria
Positive blood cultures for infective endocarditis
Typical microorganism for infective endocarditis from two separate blood cultures in the absence of a primary focus: Streptococcus viridans, Streptococcus bovis
HACEK group: Haemophilus species, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae
Community-acquired Staphylococcus aureus or enterococci
Persistently positive blood cultures, defined as recovery of a microorganism consistent with infective endocarditis from blood cultures drawn more than 12 hours apart, or all of three, or the majority of four or more separate blood cultures, with the first and last drawn at least 1 hour apart
Single positive blood culture for Coxiella burnetii or antiphase IgG antibody titer >1:800
Evidence for endocardial involvement
TTE (TEE in prosthetic valve) showing oscillating intracardiac mass on a valve or supporting structures, in the path of regurgitant jet or on implanted material, in the absence of an alternative anatomic explanation, or
Abscess, or
New partial dehiscence of a prosthetic valve

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Feb 19, 2020 | Posted by in GENERAL RADIOLOGY | Comments Off on Diseases and Disorders

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