Distribution of CD4+ T Lymphocytes at Diagnosis of Acquired Immunodeficiency Syndrome—Defining and Other Human Immunodeficiency Virus—Related Illnesses

Background: Depletion of circulating CD4 + T lymphocytes among persons infected with the human immunodeficiency virus (HIV) is associated with increased risk for development of opportunistic, life-threatening diseases and death. Methods: To describe the levels of CD4 + T lymphocytes at which acquired immunodeficiency syndrome (AIDS)—defining and other illnesses initially occur, we analyzed data from an ongoing survey of medical records of 18 062 HIV-infected patients who received medical care between January 1990 and August 1993 in more than 100 clinics, hospitals, and private practices in 10 US cities. We report the median and upper 80th percentile CD4 + T-lymphocyte counts at diagnosis. Results: We found that AIDS-defining conditions first occurred in HIV-infected patients with CD4 + T-lymphocyte counts below 0.20 × 10 9 /L (200/μL) for 80% of diagnoses. Similarly, AIDS-defining diseases occurred at counts below 0.05 × 10 9 /L for 50% of diagnoses. Exceptions to both criteria were invasive cervical cancer and pulmonary tuberculosis. Non—AIDS-defining illnesses with which 80% of patients were diagnosed at CD4 + T-lymphocyte counts below 0.20 × 10 9 /L were bacterial sepsis and retinopathy (excluding cytomegalovirus). Conclusion: Our observations support the need for continued CD4 + cell count monitoring below a level of 0.20 ×10 9 /L as a guide to diagnosis and medical management of HIV-infected persons. (Arch Intern Med. 1995;155:1537-1542)