Immune reconstitution inflammatory syndrome in HIV-infected patients with disseminated histoplasmosis

Abstract

Four HIV-1-infected patients presented with unusual clinical manifestations in the course of disseminated histoplasmosis, including liver abscesses, compressive lymphadenitis, intestinal obstruction, uveitis and arthritis within a median of 45 days after initiation of highly active antiretroviral therapy (HAART). They had a median increase of 106 CD4 cells/mul and granulomas with caseation in three. Partial immune reconstitution induced by HAART during disseminated histoplasmosis either related to the variety capsulatum or duboisii may be associated with immune reconstitution inflammatory syndrome.

Immune Restoration Diseases Reflect Diverse Immunopathological Mechanisms

“…IRD associated with intracellular pathogens were originally characterized by delayed-type hypersensitivity (DTH) immune responses, demonstrated by skin testing with mycobacterial antigens (50,51,86), and/or by granulomatous inflammation in tissues affected by IRD associated with mycobacteria (108), cryptococci (84), Histoplasma sp. (14), and Leishmania sp. (110).…”

Imported Acquired Immunodeficiency Syndrome–Related Histoplasmosis in Metropolitan France: A Comparison of Pre–Highly Active Anti-Retroviral Therapy and Highly Active Anti-Retroviral Therapy Eras

“…Four of them had been reported elsewhere. 11,17 In two cases, a 51-year old woman treated with HAART and chemotherapy for Kaposi's sarcoma and a 33-year old man who had AIDS-defining toxoplasmosis and onset of HAART three weeks before IRIS, IRIS was the first manifestation of histoplasmosis. Histoplasmosis was the first manifestation of HIV infection for the five other patients.…”

“…The existence of histoplasmosisrelated IRIS was systematically investigated using published criteria (i.e., progression of organ dysfunction or enlargement of pre-existing lesion or exaggerated inflammatory reaction and decrease in plasma HIV viral load by > 1 log copies/mL). 11,15 All IRIS and relapse cases were reviewed and validated by two infectious diseases specialists who were experts in the field. The underlying cause of death was considered to be histoplasmosis in the presence of clinical symptoms related to histoplasmosis and with a positive direct examination result or culture of H. capsulatum within one month before death.…”

Syndrome inflammatoire de reconstitution immune

“…Plusieurs éléments sont en effet évocateurs d'une reconstitution de la fonctionnalité des macrophages dans le cadre d'une réponse cellulaire spécifique de type Th1 : la repositivation de l'intradermoréaction à la tuberculine observée au cours des IRIS liés à la tuberculose [12], la mise en évidence de granulomes épithélioïdes et surtout gigantocellulaires, parfois accompagnés de nécrose et de très rares agents infectieux. Ces granulomes se voient dans les IRIS liés à une tuberculose [13], à une cryptococcose [14] (patients infectés par le VIH ou greffés) [5], à une histoplasmose [15] (patients VIH), aux candidoses hépatospléniques (patients traités par chimiothérapie en sortie d'aplasie) [16] (Figure 1 …”