The decreased number and function of lymphocytes is associated with Penicillium marneffei infection in HIV-negative patients

Background/purposePenicillium marneffei (P. marneffei) infection, which has been traditionally considered as an indicator of immunosuppression, is one of the most common systemic opportunistic infections in patients with AIDS. Recently, more and more P. marneffei infections have been documented in HIV-negative patients without underlying diseases, which challenges the traditional view that P. marneffei infection is an indicator of immunosuppression. We aimed to evaluate the number and function of lymphocytes in HIV-negative patients with P. marneffei infection.Methods15 HIV-negative P. marneffei-infected patients and 18 healthy controls were recruited and investigated. The number and function of lymphocytes were analyzed by flow cytometry.ResultsMost laboratory tests were within the reference ranges, except for a significant increase in total IgE in P. marneffei-infected patients. Lymphocyte subset analysis showed that the number of CD4⁺ T cells and NK cells was significantly decreased in HIV-negative marneffei-infected patients compared with healthy controls. However, almost half of the marneffei-infected patients still had normal levels of lymphocytes. A further analysis of cell function showed that the activation and proliferation of CD4⁺ T cells, the cytotoxicity of CD8⁺ T cells and NK cells, and the cytokine secretion potential of CD4⁺ T cells and NK cells were all impaired, in comparison with healthy controls.ConclusionsP. marneffei infection has to be regarded as an indicator of immunosuppression. A further investigation of cell function is required in patients with opportunistic infection, as the cell function may be impaired in this condition.