Clinical presentation of idiopathic CD4 lymphocytopenia

An otherwise healthy man (60s) presented to our emergency department 5 years ago with stroke-like symptoms. Underlying cryptococcal meningitis infection was ultimately discovered leading to extensive workup to rule out underlying malignancy and HIV infection. Results returned negative with the exception of a CD4 count less than 25 /mm³ Several years later, he again presented to the emergency department with fatigue. He was then found to have severe anaemia with underlying Mycobacterium avium complex (MAC) infection involving the bone marrow and a left psoas abscess. After multiple courses of antibiotic therapy targeted towards MAC, the infection persisted due to bone marrow involvement. By diagnosis of exclusion, he was eventually found to have idiopathic CD4 lymphocytopenia. Here we describe this condition, which has the potential to cause significant morbidity, and obligates the need for high clinical suspicion for timely diagnosis to enhance life quality and outcomes for patients.