Two solid-organ transplant recipients (one heart and one lung) developed severe anemia with reticulocytopenia. Both were heavily immunosuppressed. Bone marrow aspiration revealed almost complete absence of erythroid precursors. A few giant megaloblastic proerythroblasts with cytoplasmic vacuolisation and intranuclear inclusions were seen. Human parvovirus B19 (B19V)-DNA genome was found by nested-PCR assays in blood and bone marrow samples in both cases. Twelve similar cases are described in the literature. When looked for, B19V DNA was positive either in serum or bone marrow or both. Twelve of the fourteen patients were successfully treated by high dose i.v. immunoglobulin (IVIG). One patient recovered spontaneously and another after treatment with recombinant human erythropoietin (rHu-EPO) only. Transplant patients should be considered at risk for severe erythroblastopenic anemia due to B19V infection. Diagnosis is based on bone marrow examination and detection of B19V DNA by PCR in serum and/or marrow. IVIG is an effective and safe treatment. The role of erythropoietin in this indication needs further study.