Immunodeficiency with recurrent panlymphocytopenia,impaired maturation of B lymphocytes,impaired interaction of T and B lymphocytes,and impaired integrity of epithelial tissue: A variant of idiopathic CD4+ T lymphocytopenia?

Idiopathic CD4⁺ T lymphocytopenia (ICL) has been defined as a cause of immunodeficiency with a variable clinical course and an unknown etiology. Here we describe a now 18‐year‐old boy with ICL, chronic mucocutaneous candidiasis (CMC), recurrent abscesses, and relapsing aphthous and ulcerous lesions. In addition to ICL the patient frequently showed a panlymphocytopenia. An increased percentage of γ⁺δ⁺ T lymphocytes and IgD⁺ IgM⁺ B lymphocytes, and a decreased percentage of CD21⁺ B lymphocytes, were observed. In vitro assays showed normal T‐cell responses to candidin and T‐cell mitogens, but impaired B‐cell responses to pokeweed mitogen (PWM). B‐cell maturation after stimulation with Staphylococcus aureus Cowan I (SAC) and interleukin 2 (IL‐2) was nearly normal. The clinical course of the patient improved substantially on administration of constant low‐dose therapy with fluconazole.