Ann Hematol (1995) 71:181-183 9 Springer-Verlag 1995 F. Gilsanz 9 J. A. Garcia Vela 9 J. A. Vargas J. Ibafiez - F. Ofia 9 J. L6pez 9 M. Roggendorf Acquired pure red cell aplasia: a study of six cases Received: 19 April 1995 / Accepted: 15 July 1995 Abstract Persistent infection by parvovirus B19 asso- ciated with pure red cell aplasia (PRCA) has been doc- umented in immunocompromised patients. Bone mar- row failure is associated with conditions in which im- mune surveillance is impaired, and in these instances occult parvovirus infection may be suspected. In this study we have assessed by serological and molecular methods whether parvovirus B19 infection may be a more frequent cause of PRCA than hitherto suspected and whether it may be present in the absence of a typ- ical bone marrow picture. Six patients with PRCA - two with isolated PRCA and no apparent underlying disease, two with a lymphoproliferative disease, one with thymoma, and one with chronic myelomonocytic leukemia - have been studied. Four of the six patients had overt PCRA and were clearly immunocomprom- ised. Parvovirus B19 was not detected in any of the six patients by PCR analysis and serology investigating the F. Gilsanz 9 J. Ibafiez Department of Hematology, Hospital 12 de Octubre, Universidad Comptutense, Madrid, Spain J. A. Garcia Vela (5:~) 9 F. Ofia Department of Hematology, Hospital Universitario de Getafe, Avda. Derechos Humanos 30, 4~ A, E-Leganes, Madrid 28912, Spain J. A. Vargas Department of Internal Medicine, Clfnica Puerta de Hierro, Universidad Autonoma, Madrid, Spain J. L6pez Department of Hematology, Hospital Ramon y Cajal, Universidad de Alcala de Henares, Madrid, Spain M. Roggendorf Institut far Medizinische Virologie, Universit ~it sklinikum, Essen, Germany presence of IgM or IgG antibodies. Although parvovi- rus B19 infection needs to be ruled out in PRCA it represents only one, and probably not the most fre- quent, etiological factor of PRCA. Key words Parvovirus 9Anemia 9Aplasia Introduction Acquired pure red cell aplasia (PRCA) is characterized by severe anemia, low reticulocyte count, and selective absence of normal bone marrow erythroid precursors. Acquired PRCA is rare and may result from different pathogenetic mechanisms, such as the presence of anti- bodies against erythroid progenitors, a suppressor ac- tivity of T lymphocytes, the existence of a myelodys- plastic syndrome, or parvovirus B19 infection [4,12,17]. Persistent infection with parvovirus B19 associated with PRCA has been documented in patients with con- genital [8] and acquired immunodeficiency [5, 13] and in children with acute lymphoblastic leukemia [9, 16]. This is characterized by typical changes in the bone marrow with the presence of giant pronormoblasts [1-3, 5, 8-10, 13, 16, 18]. It has been shown that, often, immunocompromised hosts are unable to raise an ade- quate antibody response to the parvovirus B19 [7, 11], and the viremia persists, unless they are treated with immunoglobulin resulting in a decrease of circulating viruses and restoration of erythrocyte production [10]. It has been suggested that a proportion of PRCA may be the result of a persistent parvovirus B19 infec- tion [5]. Because in most PRCA patients the bone mar- row failure is often associated with an underlying con- dition with impairment of the immune system, infection by parvovirus B19 needs to be excluded. The diagnosis of parvovirus B19 infection in PCRA presents difficul- ties due to the poor antibody response in the immuno- compromised host [11] and the small number of viral assays available to detect this virus, as it propagates poorly in conventional cell cultures. One way to over-