Parvovirus B19-induced aplastic crises in children with hereditary spherocytosis in the Czech Republic: multicentre retrospective study

BACKGROUND: Hereditary spherocytosis is the most common congenital anaemia in Europe. In patients with this disease, parvovirus B19 infection leads to aplastic crisis - a severe complication with significant morbidity and decrease in haemoglobin concentration and reticulocyte count. METHODS: This retrospective, multicentre study, conducted at the Department of Paediatrics, Faculty of Medicine and Dentistry Palacký University and University Hospital Olomouc, and the Department of Paediatric Haematology and Biochemistry, University Hospital Brno, Czech Republic, aims to describe the clinical features, diagnostic approaches, complications, and treatment of parvovirus B19-induced aplastic crises in paediatric patients with a diagnosis of hereditary spherocytosis between January 1 and June 30, 2024. RESULTS: A total of 23 patients with a confirmed diagnosis of hereditary spherocytosis were hospitalised due to parvovirus B19-induced aplastic crisis. Their mean age was 6.9 years. The most frequent clinical symptoms were fever (p-value < 0.0001), pallor (p-value < 0.0001), fatigue (p-value 0.0001), vomiting (p-value 0.001), pain (p-value 0.004), and cough (p-value 0.009). Erythema infectiosum was rare. A mean haemoglobin concentration was 4.93 g/dL (range from 2.9 to 7.4 g/dL). Other abnormal haematological parameters included leukopenia (26.0%), thrombocytopenia (8.7%), or pancytopenia (26.0%). Mean transfusion requirements were 2.74 transfusion units of red blood cells. There was no significant difference between men and women in age, haemoglobin level, and number of transfusion units. CONCLUSION: This study provides a frequency of multiple clinical symptoms of parvovirus B19-induced aplastic crises in children with hereditary spherocytosis during an epidemic, together with haematological parameters and transfusion requirements. Beginning in January 2024, we have observed more Parvovirus B19 aplastic crises than expected. Similar increase of incidence of parvovirus B19-induced aplastic crises incidence has been reported across Europe and North America.