title: Adult T-cell leukemia/lymphoma and cluster of HTLV-I associated diseases in Brazilian settings.
abstract: We studied the transmission routes of human T-cell lymphotropic virus type I (HTLV-I) within families of 82 Brazilian patients diagnosed with adult T-cell leukaemia/lymphoma (ATL). Diagnosis of ATL in 43 male and 39 female patients was based on clinical and laboratory criteria of T-cell malignancy and detection of HTLV-I monoclonal integration. Samples were tested for HTLV antibodies and infection was confirmed as HTLV-I by Western Blot and/or polymerase chain reaction (PCR) assays. Overall 26/37 (70%) of mothers, 24/37 (65%) of wives, 8/22 (36%) of husbands, 34/112 (30%) of siblings and 10/82 (12%) offspring were HTLV-I infected. In 11 ATL patients, mothers were repeatedly HTLV-I seronegative, but HTLV-I pol or tax sequences were detected in 2 out of 6 cases tested by PCR. ATL patients with seronegative mothers related the following risk factors for HTLV-I infection: 6 were breast-fed by surrogate mothers with unknown HTLV-I status, 4 had a sexually promiscuous behaviour and 1 had multiple blood transfusions at a young age. Familial aggregation of ATL and other HTLV-I associated diseases such as HTLV-I myelopathy (HAM/TSP) and or uveitis, ATL in sibling pairs or in multiple generations was seen in 9 families. There were 6 families with ATL and TSP sibling pairs. In 3 families at least one parent had died with lymphoma or presenting neurological diseases and 2 offspring with ATL. Further to the extent of vertical and horizontal transmission of HTLV-I infection within ATL families, our results demonstrate that mothers who provide surrogate breast-milk appear to be an important source of HTLV-I transmission and ATL development in Brazil.
authors.affiliation: Cell Marker Laboratory-Department of Hematology of Instituto Nacional de Cancer, Hematologia Clinica, Praça Cruz Vermelha, 23, 7th floor, CEP 20 230 030-Rio de Janeiro, Brazil. mpombo@inca.org.br
authors.forename: M S
authors.initials: MS
authors.lastname: Pombo-de-Oliveira
authors.forename: S M
authors.initials: SM
authors.lastname: Carvalho
authors.forename: D
authors.initials: D
authors.lastname: Borducchi
authors.forename: J
authors.initials: J
authors.lastname: Dobbin
authors.forename: J
authors.initials: J
authors.lastname: Salvador
authors.forename: R B
authors.initials: RB
authors.lastname: Correa
authors.forename: A
authors.initials: A
authors.lastname: Moellman
authors.forename: P
authors.initials: P
authors.lastname: Loureiro
authors.forename: C
authors.initials: C
authors.lastname: Chiattone
authors.forename: M
authors.initials: M
authors.lastname: Rios
mesh_terms: D001938:Brazil / Q000453:epidemiology; D001942:Breast Feeding / Q000009:adverse effects; D018562:Disease Transmission, Infectious / Q000706:statistics & numerical data; D005192:Family Health; D005260:Female; D015490:HTLV-I Infections / Q000175:diagnosis / Q000453:epidemiology / Q000635:transmission*; D006801:Humans; D018445:Infectious Disease Transmission, Vertical / Q000706:statistics & numerical data; D015459:Leukemia-Lymphoma, Adult T-Cell; D008297:Male; D009679:Nuclear Family; D015493:Paraparesis, Tropical Spastic; D010375:Pedigree