Serological and virological evaluation of human T-lymphotropic virus type 1 infection in family groups from Tumaco, Colombia / Evaluación serológica y virológica de la infección por el virus linfotrópico de células T humanas de tipo 1 en grupos familiares de Tumaco, Colombia

Introduction: To date there has been no statistical evaluation of the profiles of immunoglobulin classes and viral replication as variables in the study of HTLV-1 infection and circulation among families in virus-endemic areas of Colombia. Objective: To evaluate the correlation of several immunological and molecular characteristics with the transmission and circulation of HTLV-1 among families in the town of Tumaco. Materials and methods: Plasma levels of HTLV-1 specific immunoglobulin classes IgG, IgM and IgA1, as well as IgG and sIgA in oral fluids, were calculated for 32 members of 10 family groups from Tumaco in which the mother and at least one child were infected with the virus. Levels of the different immunoglobulin classes were correlated with viral RNA circulating in plasma or oral fluids and the proviral burden as detected by RT-PCR. Results: Significant differences were determined between mothers and carrier children for immunoglobulin levels (p=0.037) and proviral burden (p=0.002). The overall estimate of IgG in plasma and sIgA in oral fluids could be correlated with the circulation of free viral RNA in both fluids and high proviral burden, and associated with HAM/TSP mothers. The detection of anti- tax IgG in plasma revealed differences between HAM/TSP mothers and their offspring. Conclusion: The study of immunological and molecular variables permitted the analysis of HTLV-1 circulation among families of Tumaco. The strong correlation between levels of IgM specific for the virus and viral RNA circulating in fluids indirectly confirmed the transmission of HTLV-1 among families.

Introducción. Todavía no hay una evaluación estadística de los perfiles de las clases de inmuno- globulina s y la replicación viral, como variables para estudiar la infección y la circulació n del HTLV-1 en familias de zonas endémicas en Colombia. Objetivo. Evaluar la correlación de varias características inmunológicas y moleculares, con la transmisión y circulación del virus en familias del municipio de Tumaco. Materiales y métodos. Se calcularon los niveles de IgG, IgM e IgA1 en plasma, e IgG y IgA secretoria en fluido oral, de 32 miembros de 10 grupos familiares de Tumaco, en los que la madre y, al menos, un hijo estaban infectados con el virus. La concentración de las diferentes clases de inmunoglobulinas se pudo correlacionar con la circulación de ARN viral libre en plasma y fluido oral, y la carga proviral, según su detección mediante reacción en cadena de la polimerasa de transcripción inversa. Resultados. Se encontraron diferencias significativas en los niveles de inmunoglobulinas (p=0,037) y en la carga proviral (p=0,002) entre madres e hijos portadores. La estimación total de IgG en plasma e IgA secretoria en fluido oral, se pudo correlacionar con la circulación de ARN viral libre en ambos fluidos y una alta carga proviral, y se asoció con las madres paraparesia espástica tropical o mielopatía asociada con el HTLV-1. La detección en plasma de IgG anti-Tax reveló diferencias entre ellas y sus hijos. Conclusión. El estudio de las variables inmunológicas y moleculares permitió analizar la circulación del HTLV-1 en familias de Tumaco. La fuerte asociación entre los niveles de IgM específica para el virus y el ARN viral circulante en los fluidos y la carga proviral, confirmó indirectamente la transmisión intrafamiliar del virus.

High HTLV-1 proviral load, a marker for HTLV-1 associated myelopathy/tropical spastic paraparesis, is also detected in patients with infective dermatitis associated with HTLV-1

Salvador (BA, Brazil) is an endemic area for human T-cell lymphotrophic virus type 1 (HTLV-1). The overall prevalence of HTLV-1 infection in the general population has been estimated to be 1.76%. HTLV-1 carriers may develop a variety of diseases such as adult T-cell leukemia/lymphoma, HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and infective dermatitis associated with HTLV-1 (IDH). IDH is a chronic and severe form of childhood exudative and infective dermatitis involving mainly the scalp, neck and ears. It has recently been observed that 30% of patients with IDH develop juvenile HAM/TSP. The replication of HTLV-1 has been reported to be greater in adult HAM/TSP patients than in asymptomatic HTLV-1 carriers. In the current study, the proviral load of 28 children and adolescents with IDH not associated with HAM/TSP was determined and the results were compared to those obtained in 28 HTLV-1 adult carriers and 28 adult patients with HAM/TSP. The proviral load in IDH patients was similar to that of patients with HAM/TSP and much higher than that found in HTLV-1 carriers. The high levels of proviral load in IDH patients were not associated with age, duration of illness, duration of breast-feeding, or activity status of the skin disease. Since proviral load is associated with neurological disability, these data support the view that IDH patients are at high risk of developing HAM/TSP.

Adult T-cell leukemia/lymphoma in a Korean: a case report

The clinicopathologic features of a Korean patient with adult T-cell leukemia/lymphoma(ATLL) are presented. A 51-year-old man, who has lived in Korea since birth, had multiple cutaneous nodules and multiple lymphadenopathy for the previous two months. A histopathologic study of the lymph node and skin lesion revealed T-cell non-Hodgkin's lymphoma of pleomorphic type, medium and large cell type. Peripheral blood examination showed leukemic features with 30% of abnormal lymphoid cells. HTLV-I proviral DNA pX region was detected in the DNA from peripheral blood mononuclear cells(PBMC) and the specific gag, pol, and env HTLV-I sequences were detected in the lymph node using polymerase chain reaction technique. Human T-cell leukemia/lymphoma type I(HTLV-I) antibodies were present in the serum. An immunophenotypic study of the lymph node revealed CD4 positive and CD8 negative helper/inducer T cell type surface markers. This case is the acute type, i.e. prototypic ATLL. He was treated with an intensive chemotherapy including cyclophosphamide, etoposide, doxorubicin, vincristine, and prednisone. Despite initial transient improvement, the tumor progressed after three cycles of the regimen and became refractory to further chemotherapy. These clinicopathologic findings, including the immunophenotypic analysis, established with certainty the diagnosis of HTLV-I-induced adult T-cell leukemia/lymphoma.