Objective: To describe a localized form of Mycobacterium avium intracellulare (MAI) infection occurring concurrently with the restoration of cutaneous delayed-type hypersensitivity (DTH) responses to mycobacterial antigens after commencement of zidovudine therapy in immunodeficient HIV-infected patients.
Patients: The first 108 Western Australian patients with a CD4+ T-cell count of < 200 x 10(6)/l and/or symptomatic disease to be given zidovudine (ZDV), of whom 72 had adequate DTH data.
Methods: DTH responses to seven antigens were measured by the 'Multitest' method before and on at least two occasions during the 6 months after commencing ZDV. All patients were reviewed at regular intervals and clinical events recorded.
Results: Of the 64 patients who were anergic to tuberculin before commencing ZDV, 27 (42%) developed a DTH response to tuberculin after ZDV. Four of the nine patients with a 'Multitest' tuberculin response of > or = 8 mm and one patient who developed a positive Mantoux test to M. avium purified protein derivative developed an illness characterized by localized MAI infection, lymphadenopathy and/or severe fevers after 1-2 weeks.
Conclusions: The development of localized MAI infection and/or fevers shortly after commencing ZDV in immunodeficient HIV-infected patients may reflect restoration of cellular immunity to mycobacterial antigens in some patients rather than early failure of therapy or hypersensitivity to ZDV.