—We are pleased by the thoughtful comments of Tor et al in response to our above-referenced study of hospitalized intravenous drug abusers. In addition to presenting new data, this letter questions the significance of abnormalities in both function and number of lymphocytes in non-longitudinal studies of acute illness. In fact, this query cuts to the heart of what should be, but is not, a growing controversy: How does one use and interpret clinical tests, such as immunophenotypic studies, that are suggestive of a disease but are influenced by many non—disease-related factors?
We agree that there are many infections that may affect the T-cell subsetting technique. Patient characteristics such as sexual preference and history of drug abuse are important, as are underlying disease, age, and methodologic details such as the time of sampling.1-8 Anesthesia may inhibit lymphocyte transformation as measured by response to mitogens.9 A further complication of immunophenotyping
Layon J, Warzynski M, Idris A. T-lymphocyte Subsets in Hospitalized Drug Abusers: Is There More Than Meets the Eye?-Reply. Arch Intern Med. 1985;145(11):2136. doi:10.1001/archinte.1985.00360110212059