PF744 SPECTRUM OF PARVOVIRUS B19 INFECTION IN CHILDREN WITH SICKLE CELL DISEASE: ATYPICAL PRESENTATIONS

Abstract

Background:Human Parvovirus B19 (P‐B19) infection is known to cause aplastic crisis in sickle cell disease (SCD) patients. However, few studies have reported rare unusual complication of Parvovirus in SCD.Aims:To describe the demographic and clinical characteristics of Parvovirus B19 infection in hospitalized children with SCD admitted to Sultan Qaboos Universirty Hospital (SQUH) throughout the period (2009–2018), with special emphasis on atypical presentations.Methods:Descriptive retrospective study.Results:Out of 4688 admission episodes of pediatric patients with SCD throughout the duration of study, 108 patients (61 males & 47 females) were diagnosed with Parvovirus B12 infection evidenced by positive PCR, with an age ranging from 18 months to 13.5 years. Parvovirus B19 infection accounts for 2.3% of the total admissions in our institution. It is the 4th commonest cause of hospitalizing children with SCD, just after painful crisis, acute chest syndrome, and fever without focus respectively. Out of the 108 cases, 94 children presented with isolated classical aplastic (erythroblastopenic) crisis, associated with variable grades of fever +/‐ joint pains. The majority of patients required transfusion once, although 20 of them needed twice or more transfusions. Atypical presentations were encountered in 14 patients (12.9%). The commonest is splenic sequestration coupled with aplastic crisis and marked reticulocytopenia (12 cases). The first two cases were siblings diagnosed in 2010. Since then, this complication has been increasingly recognized in our patients and we have noted a familial tendency to develop Parvovirus B19‐induced acute splenic sequestration, indicating a possible genetic predisposition to this complication, which is seen in our cohort in a much higher frequency compared to the published literature.Severe Parvovirus B19‐induced bone marrow failure was seen in a 7 year‐old male patient. This boy developed marked pancytopenia associated with protracted high grade fever, acute chest syndrome and severe painful crisis. The only positive culprit was Parvovirus B19 which was persistently positive with a very high viral load detected with PCR. He required multiple top ups & exchange transfusions. Ultimately, Intravenous Immunoglobulins (IVIG) were administered to control his overwhelming viral infection, and he responded successfully. Another interesting case is a 5‐year‐old boy with SCD and G6PD deficiency. He presented with increasing anemia, jaundice and hemoglobinuria. All lab parameters were consistent with acute intravascular hemolysis, combined with suboptimal marrow response evidenced by reticulocytopenia. Coombs test and flow cytometry for Paroxysmal Nocutrnal Hemoglobinuria were negative. Parvovirus B19 PCR was positive in a significantly high copy number. The boy was diagnosed as a case of acute intravascular hemolytic anemia due to G6PD deficiency triggered by concomitant Parvovirus B19 infection which explains the reticulocytopenia. The patient required transfusion three times, then discharged uneventfully.Summary/Conclusion:Parvovirus B19 infection is common in children with SCD. Clinical presentations are not confined to classical aplastic crisis. High index of suspicion is needed to identify Parvovirus specially in cases presented with acute splenic sequestration. We recommend screening for Parvovirus in all cases presented with acute splenic seqestration coupled with suboptimal reticulocyte reponse. In severe refractory cases of Parvo infection, IVIG might be used as a salvage therapy.