Sickle Cell Anemia



Sickle Cell Anemia


R. Brooke Jeffrey, MD





Key Facts


Terminology



  • Hemolytic anemia due to abnormal hemoglobin, resulting in deformation of red blood cells and leading to microvascular occlusion and infarcts


Imaging



  • Best imaging tool



    • NECT to visualize calcified spleen


    • US to visualize gallstones


    • Chest and spine radiographs for pulmonary and spinal findings


  • Best diagnostic clue



    • Small, densely calcified spleen on NECT


    • Papillary necrosis on IVP; cholelithiasis in African-American pediatric patient


Top Differential Diagnoses



  • Asplenia


  • Splenectomy


  • Papillary necrosis from other causes


  • Bone infarcts from other causes


Clinical Issues



  • Most common signs/symptoms



    • Acute, painful vasoocclusive crisis


    • Acute bone and chest pain


  • Prognosis improving



    • Median survival in United States now 40-50 years


  • In adulthood, end organ failure has major impact on survival


Diagnostic Checklist



  • Consider prior splenectomy if spleen not identified


  • Image interpretation pearls



    • Constellation of chest, bone, renal, and splenic lesions supports diagnosis






(Left) Axial NECT in a 35-year-old woman who presented with homozygous sickle cell anemia demonstrates a small and heavily calcified spleen image, also known as autosplenectomy. (Right) Axial T2* GRE MR in the same patient reveals low intensity in the liver, indicative of hemosiderosis from hemolysis and transfusions. A peculiar finding is the very low intensity in the renal cortex image, which is attributed to the deposition of hemosiderin within the proximal convoluted tubules.






(Left) Axial NECT in a patient who presented with sickle cell anemia and severe LUQ pain demonstrates a heavily calcified and heterogeneous spleen image, indicating chronic and possibly acute infarction. (Right) Gross pathology splenectomy specimen from the same patient illustrates a mottled spleen with capsular discoloration image that was heavily calcified on microscopy.



TERMINOLOGY


Abbreviations



  • Sickle cell anemia (SCA)


Definitions



  • Hemolytic anemia due to abnormal hemoglobin, resulting in deformation of red blood cells and leading to microvascular occlusion and infarcts


IMAGING


General Features



  • Best diagnostic clue



    • Small, densely calcified spleen on NECT


    • Papillary necrosis on IVP


    • Cholelithiasis in African-American pediatric patient


    • Salmonella osteomyelitis in young African-American patient


  • Size



    • Spleen may be undetectable (autosplenectomy) but rarely may enlarge due to sequestration syndrome


Imaging Recommendations



  • Best imaging tool



    • NECT to visualize calcified spleen


    • US to visualize gallstones


    • Chest and spine radiographs for pulmonary and spinal findings


Radiographic Findings

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Jun 8, 2016 | Posted by in GENERAL RADIOLOGY | Comments Off on Sickle Cell Anemia

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