Tuberculin Testing of Kidney Allograft Recipients and Donors Before Transplantation

Abstract

Immunocompromised patients such as those with chronic renal failure requiring hemodialysis (HD) are at increased risk of developing tuberculosis (TB). The gold standard screening tool used to detect tuberculosis is the tuberculin test, which owes its popularity to its ease of administration and high sensitivity. This study was done to identify the incidence of tuberculin test positivity among dialysis patients before transplantation and also in volunteer living kidney donors. Patients and methods This cross-sectional, comparative study was done on 308 kidney allograft recipient candidates, 80 potential living unrelated and related donors within a few months before transplantation, and 855 control cases before employment. Patients were tuberculin-tested using the Mantoux technique. The PPD (purified protein derivative)-positive dialysis patients were compared with PPD-negative subjects, regarding age, gender, dialysis duration, cause of chronic renal failure, and nutritional state as well as PPD test results in potential donors. Patients were divided into <10 mm versus ≥10 mm induration. Statistical analysis was performed using SPSS 11.0. Results The mean age of the donors was 26.6 ± 4.6 years with a male:female ratio of 87.5%:12.5%. The tuberculin test was positive in 11.25% of cases, all of whom were males with with induration >10 mm. There was no significant difference regarding the PPD results and age. The mean age of recipients was 40.1 ± 14.7 years with a male/female ratio of 1.3:1. The tuberculin test was positive in 33.6% of recipient candidates. Mean duration on dialysis was 2.5 ± 1.2 years. No significant correlation existed regarding the dialysis duration, cause of renal failure, c-reactive protein, erthrocyte sedimentation rate, and response to tuberculin test. There was a direct relationship between age and PPD test results (Pearson correlation +192). Conclusion Our results showed that more dialysis patients were PPD positive compared with donors.