Sarcoma de Kaposi epidémico en África Subsahariana / Epidemic Kaposi sarcoma in Sub-Saharan Africa

El sarcoma de Kaposi se ha convertido en uno de los tumores más prevalentes en África tras la epidemia de VIH, que afecta de una manera similar a hombres y mujeres. El retraso diagnóstico y el limitado acceso a tratamiento antirretroviral o quimioterapia condicionan el pronóstico de los pacientes que lo padecen. En este artículo se realiza una revisión sobre la referida enfermedad, con el objetivo de describir sus aspectos más relevantes en los últimos años en África, como son su epidemiología, caractéristicas clínicas y opciones terapéuticas existentes. Este tumor es provocado por la infección por virus herpes humano tipo 8, que resulta más prevalente en las zonas rurales del continente africano. Se postula la transmisión a través de la saliva como la vía más importante de contagio en África. La inmunodepresión que causa el VIH favorece el efecto oncogénico del virus. La forma epidémica de SK se manifiesta inicialmente como lesiones hiperpigmentadas o violáceas en la piel, que pueden extenderse a linfáticos o mucosas y a nivel sistémico, principalmente a pulmón o aparato digestivo. El síndrome de reconstitución inmune sistémica puede complicar la evolución del paciente. El inicio temprano de la terapia antirretroviral resulta imprescindible. Además, el pronóstico de los pacientes mejora con la suma de tratamiento quimioterápico con doxorrubicina, vincristina, etopóxido o bleomicina principalmente(AU)

Kaposi sarcoma (KS) has become one of the most prevalent tumors in Africa after the HIV epidemic. KS affects both men and women. Diagnostic delay and limited access to antiretroviral treatment or chemotherapy have an impact on the prognosis of KS patients. A review was conducted about KS with the purpose of describing its most outstanding characteristics in recent years in Africa, such as its epidemiology, clinical features, and existing therapeutic options. This tumor is caused by infection with human herpesvirus 8, which is more prevalent in rural areas of the African continent. Transmission via saliva was found to be the most important transmission route in Africa. HIV-related immunosuppression fosters the oncogenic effect of the virus. The epidemic form of KS initially presents as hyperpigmented or violet-colored skin lesions which may extend to lymph nodes or mucosae, or systemically, mainly to the lungs or the digestive tract. Systemic immune reconstitution syndrome may complicate the patient's evolution. Early start of antiretroviral therapy is indispensable. Additionally, prognosis improves with chemotherapy with doxorubicin, vincristine, etoposide or bleomycin, mainly(AU)

Detection of human herpesvirus 8 DNA in pemphigus and chronic blistering skin diseases

Increased incidences of Kaposi's sarcoma and lymphoid malignancies have been observed in patients with pemphigus, and the human herpesvirus 8 (HHV-8) is very strongly associated with these tumors. Because the virus may be one of the triggering factors of pemphigus, we undertook this study to screen for the presence of HHV-8 in chronic blistering skin diseases including pemphigus. A total of 45 paraffin-embedded specimens were studied using nested polymerase chain reaction (PCR) with primers to amplify a 160-base pair HHV-8 fragment. HHV-8 DNA could be detected in 7 of 9 patients with pemphigus vulagris, and 1 of 2 with pemphigus foliaceus. All specimens of other blistering skin diseases were negative for HHV-8. On sequencing PCR products, the sequences were almost identical with the prototypic sequence for HHV-8, and a few base- pair substitutions at 1086C-T and 1139A-C were detected. The results of our study suggests that HHV-8 might have trophism for pemphigus lesions. Further studies including comparison of HHV-8 DNA load in both lesional and normal skin in the same patient, serological and animal studies would be helpful to study the relationship between HHV-8 and pemphigus.

Detection of human herpesvirus 8 DNA in pemphigus and chronic blistering skin diseases

Increased incidences of Kaposi's sarcoma and lymphoid malignancies have been observed in patients with pemphigus, and the human herpesvirus 8 (HHV-8) is very strongly associated with these tumors. Because the virus may be one of the triggering factors of pemphigus, we undertook this study to screen for the presence of HHV-8 in chronic blistering skin diseases including pemphigus. A total of 45 paraffin-embedded specimens were studied using nested polymerase chain reaction (PCR) with primers to amplify a 160-base pair HHV-8 fragment. HHV-8 DNA could be detected in 7 of 9 patients with pemphigus vulagris, and 1 of 2 with pemphigus foliaceus. All specimens of other blistering skin diseases were negative for HHV-8. On sequencing PCR products, the sequences were almost identical with the prototypic sequence for HHV-8, and a few base- pair substitutions at 1086C-T and 1139A-C were detected. The results of our study suggests that HHV-8 might have trophism for pemphigus lesions. Further studies including comparison of HHV-8 DNA load in both lesional and normal skin in the same patient, serological and animal studies would be helpful to study the relationship between HHV-8 and pemphigus.

Human herpes virus 8 and kaposi's sarcoma: A review

Kaposi's Sarcoma (KS) was first described one century ago as a disease occurring in elderly men manifested as an indolent cutaneous form. After the onset of human immunodeficiency virus type I (HIV-1) infection, KS became epidemic which, in association with HIV, presented as an aggressive, systemic disease. Recently, the recognition that a novel human herpes virus-8 (HHV-8) was highly prevalent among KS patients provided strong evidence to indicate that HHV-8 was the etiology of KS. The pathogenesis of KS in AIDS patients is still controversial, but there is evidence suggesting that KS is a cytokine-mediated disease, and that increased levels of inflammatory cytokines in AIDS patients were responsible for the aggressive pattern of disease seen in such patients. The recently developed serological assays for detection of HHV-8 antibodies have made possible a better understanding of the prevalence of HHV-8 in different populations, and this has allowed a deeper understanding of HIV-8 epidemiology.