Parvovirus B19 (B19V) infection could cause clinical manifestations depending on the host‘s immunologic and hematologic status. In immunocompetents individuals, clinical manifestations range from asymptomatic, or flu-like symptoms in childhood including a viral exanthem (fifth disease) to a fatal hydrops fetalis in pregnant women. B19V infect red blood cell (RBC) precursors and in immunocompromised hosts, such as HIV-infected patients, it could be manifested as pure red cell aplasia and chronic anemia. B19V may cause transient aplastic crisis (TAC) in patients with increased RBC destruction, including hereditary spherocytosis (HS).

To report cases of B19V infection in HIV-positive adults in follow-up at Instituto Nacional de Infectologia Evandro Chagas.

Case 1: A 27-year-old black male with HIV since childhood on irregular use of antiretroviral therapy (ART) complained of vertigo, headache, vomiting, fever. In April 2021 he had Hb 1,7 g/dL, Ht 6.5%, reticulocytes 0%, HIV viral load 40,305 cps/mL and CD4+ count 6 cells/μL. Up to October 2021 he required multiple RBC transfusions. Myelogram showed giants proerythroblasts with nuclear inclusions, B19V real time polymerase chain reaction (qPCR) detected 4.3 × 1010 IU/mL, and B19V anti-IgM was negative. He received intravenous immunoglobulin (IVIG) and stabilized RBC counts. Nine months after treatment, he remained asymptomatic but had 11 cells/ μL CD4+ count and 27,642 HIV cps/mL due to poor adherence to ART. B19V was still detectable in qPCR (1.8 × 106 IU/mL), but he did not receive any additional treatment because blood counts were normal. Case 2: A 61-year-old white male with HIV since 2009 on regular use of ART, undetectable HIV viral load, but historically low CD4+ count, presented four weeks of lethargy, and an acute incident of dizziness, diarrhea, and syncope. He exhibited pancytopenia (Hb 5.6 g/dL, Ht 15.2%, WBC 1.48 × 109/L, and platelets 41,000 per mm3), non-immune hemolytic anemic features, jaundice, and palpable spleen. Reticulocyte counts were unavailable. He received transfusions of RBC, the HIV viral load at admission was undetectable, and CD4+ count 127 cells/ μL. The myelogram presented giant proerythroblasts with nuclear inclusions, and bone marrow had 95% cellularity and mild erythroid hyperplasia. B19V anti-IgM was indeterminate, while B19V qPCR detected 8.9 × 103 IU/mL, in August 2021. The patient received IVIG and nine months later, showed resolution of pancytopenia, but maintained elevated indirect bilirubin, indicative of chronic hemolysis. B19-DNA was no longer detected by qPCR, hematoscopy showed spherocytes, and the osmotic fragility test suggested RBC membranopathy, revealing an undiagnosed HS.

Anemia is a common finding in the HIV setting, is often multifactorial, and represents a significant risk factor for mortality in AIDS. Our study highlights the importance of B19V infection be considered as a part of the differential diagnosis of anemia in this group. Clinicians should search for typical bone marrow and virologic findings. Identification of B19V DNA by qPCR was essential herein because of low sensitivity of serologic tests.

Our findings showed that adherence to ART and the status of immunosuppression were crucial to the parvovirus clearance after IVIG. These cases highlight the challenging management of refractory parvovirus disease in immunosuppressed patient.