30 F Crohn’s dz presents w/ fever, fatigue, headache, myalgia. Son goes to daycare had transient fever 10 days ago. Pt has Hb 8, retic<0.5%. Diagnosis?
ParvovirusB19 recent sick contact son had slapped cheek rash. Bone marrow aspirate: giant pronormoblasts w/ multiple intranuclear inclusions and cytoplasmic projections (dog ear)
Reticulocyte count was less than 0.5%, indicates complete absence of a bone marrow response to the anemia (i.e., the absence of reticulocyte production) hypoproliferative anemia
Ddx: Deficiencies of folate, vitamin B12, and iron can lead to hypoproliferative anemia but her levels were normal
Ddx: Infiltrative processes involving bone marrow that can lead to hypoproliferative anemia include mycobacterial infection, granulomatous dz (sarcoidosis) myelofibrosis, lysosomal storage diseases &cancer. patient had no organ involvement suggestive of granulomatous dz or cancer
Ddx: Antibody-mediated pure red-cell aplasia can be induced by pregnancy, viral hepatitis, HIV infection, leukemia, lymphoma, thymoma, and autoimmune conditions.
Sudden onset of this patient’s anemia suggests a rapid process rather than a slowly developing autoimmune disease or cancer
Parvovirus directly infects erythrocytes & erythrocyte precursor cells & causes hypoproliferative anemia. fever, malaise, headache are typical. It causes failure of bone marrow to compensate for normal red-cell loss, thereby leading to a predictable decline in hemoglobin level
Spreads through respiratory secretions, such as saliva, sputum, or nasal mucus, when an infected person coughs or sneezes.