RESUMEN
As anergy is common in patients with chronic renal failure (CRF), the use of tuberculin skin test (TST) is controversial. Therefore, determination of the factors that affect the TST reactivity would increase the diagnostic value of the test. The aim of the present study was to investigate the factors affecting TST reactivity and evaluate the relationship between T-lymphocyte subsets and TST reactivity. We thus examined 44 patients (mean age 46.6 +/- 15.6 years, 25 males, duration of CRF 5.6 +/- 5.2 years), performed TST (an induration with a diameter of 5 mm or more was considered as positive) and measured Tlymphocyte subsets and biochemical parameters. Twenty-three patients were on hemodialysis, six were on peritoneal dialysis, seven were transplant recipients, and eight were on medical treatment. Eleven patients (25%) had immunosuppressive treatment. Eleven patients (25%) had two, 29 patients (66%) had one, and four patients (9%) had no BCG scars. Five patients (11%) had low body mass index (BMI). T-lymphocyte subsets were as follows: CD4= 40.7 +/- 7.6%, CD8= 32 +/- 8.9%, CD4/CD8= 1.7 +/- 2.5%, CD3= 71.4 +/- 9.4%, CD19= 6.3 +/- 5.1%, NK= 9.7 +/- 5.9. Twenty-two patients had positive TST reactivity. No relation was found between TST reactivity and age, gender, co-morbidity, BCG vaccination, BMI, immunosuppressive therapy, duration and treatment of CRF. Similarly, TST reactivity was not related to the biochemical parameters and Tlymphocyte subsets. These data provide that tuberculin reactivity does not seem to be associated with T-lymphocyte dysfunction and clinical features in patients with chronic renal failure.