[Lymph node tuberculosis in HIV-1 seropositive patients in Central Africa. A characteristic histopathologic picture]

Abstract

Sixty two patients fulfilling the definition established by the Centers for Disease Control in 1982 for persistent lymphadenopathy syndrome, thought to be related to the human immunodeficiency virus (HIV) infection, were selected at the Butare university hospital, in Rwanda, between 1987 and 1988. Forty-five (73%) of them were indeed seropositive. Fifteen patients of sixty two (24%) presented unexpectedly evidence of tuberculous adenitis on biopsy. Three of them, found HIV-1 seronegative, showed a classical follicular adenitis, whereas the twelve other seropositive patients presented unusual histologic features, consisting of more or less immature tuberculoid granulomas with an abundant caseating and often granular necrosis, containing acid fast bacilli. Numerous blood vessels and abundant plasmacytosis were found in non-necrotic areas. Semi-quantitative evaluation of the granulomatous reaction components provided a histological spectrum probably related to the degree of impairment of the cellular immune response, which could be of prognostic significance. In areas where populations are exposed to both HIV and M. tuberculosis, it appears that lymph node biopsy with mycobacterial culture should be recommended in order to detect occult tuberculosis among HIV-seropositive persons, allowing accurate medical care and adequate public health surveillance.

PIP: During 1987-1988 in Burundi, 62 patients presented at Butare University Hospital with chronic lymphadenopathy syndrome. Physicians suspected that the syndrome was a result of HIV infection. 45 (73%) were indeed HIV seropositive. The biopsy of the lymph nodes revealed that 15 of the 62 patients (24%) had histologic characteristics of tuberculosis (TB). 12 of the patients with lymph node TB were HIV seropositive. The other three cases exhibited classical signs of follicular adenitis. All the HIV positive cases with lymph node TB had many enlarged lymph nodes which were superficial, easily palpated, and moveable. They also had little mass. Specifically, they had rather immature granulomas with considerable necrosis which turns the tissue into a dry mass resembling cheese, and, sometimes, granular necrosis. These granulomas had acid fast bacilli. The non-necrotic areas had many blood vessels and considerable excess of plasma cells in the blood. Thus, the lymph nodes of the HIV positive TB cases were different than those of the 3 HIV negative cases. The semi-quantitative evaluation of the components of the granulomatous TB reaction allowed the researchers to rank the lesions in a manner probably parallel to the degree of deterioration of the cellular immune response. This semi-quantitative evaluation could constitute a prognostic value. Lymph node biopsy and mycobacterial culture appear then to be indicated among HIV seropositive persons living where there is a joint HIV-1/TB endemic. This allows clinicians to detect concealed TB among HIV seropositive individuals and to introduce as fast as possible an adequate anti-TB treatment and to enable a fight against the progression of the illness and its propagation in a group of sick persons.