title: Fever of unclear origin and cytopenia because of acute splenic sequestration in a young immunocompetent carrier of beta-globin mutation for Hb Valletta.
abstract: Fever of unclear origin is a clinical challenge in medical practice. Infectious diseases, neoplasms, and collagen vascular illnesses are its main causes in adults and children. Acute splenic sequestration crises, a known potentially fatal complication of sickle cell disease and sickle beta-thalassemia, are uncommon in beta-heterozygosis. We describe a case of prolonged recurrent episodes of fever with spontaneous resolution, commencing at age 10 in a 15-year-old boy with a history of hypochromic microcytic anemia attributed to a thalassemic trait. He was admitted twice to our university hospital for continuous-remittent fever with a pruritic, macular evanescent Still's skin rash, severe splenomegaly, leucopenia, thrombocytopenia, and sudden aggravation of anemia. Infectious, rheumatologic, autoimmune, and hematologic illnesses were excluded. A genetic-based study revealed heterozygosis of the beta-globin gene for a A>C (Thr>Pro) substitution at position 87 called Hemoglobin Valletta (alpha 2 beta 2 87 PRO) with a C>G transition in homozygosis in beta-globin intronic polymorphism intervening sequence 2 at nucleotide 745. After a follow-up period of 1 year without treatment, the young patient remains apyretic and in good general clinical health with persistent microcythemia and hepatosplenomegaly. Acute splenic sequestration crisis and related cytopenia may be an unusual complication of fever of unclear origin in a beta-thalassemic carrier of a Hemoglobin Valletta mutation and polymorphism in homozygosis of intervening sequence 2 at nucleotide 745. This hemoglobinopathy may predispose to a clinical phenotype of minor or intermediate thalassemia and, during a febrile illness, to hemoglobin instability and splenic sequestration.
authors.affiliation: Biomedical Department of Internal and Specialistic Medicine, University Hospital of Palermo, Palermo, Italy.
authors.forename: Gaspare
authors.initials: G
authors.lastname: Parrinello
authors.forename: Daniele
authors.initials: D
authors.lastname: Torres
authors.forename: Salvatore
authors.initials: S
authors.lastname: Paterna
authors.forename: Pietro
authors.initials: P
authors.lastname: Di Pasquale
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Licata
mesh_terms: D000293:Adolescent; D000328:Adult; D000740:Anemia / Q000097:blood / Q000150:complications / Q000235:genetics; D002648:Child; D005334:Fever / Q000209:etiology* / Q000235:genetics / Q000503:physiopathology; D006402:Hematologic Diseases / Q000209:etiology* / Q000235:genetics / Q000503:physiopathology; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006801:Humans; D007121:Immunocompetence; D008297:Male; D009154:Mutation; D013154:Spleen / Q000473:pathology*; D055544:beta-Globins / Q000235:genetics*
chemical_list: D006455:Hemoglobins, Abnormal; D055544:beta-Globins; C068750:hemoglobin Valletta