Biologic Drug Effect in PPD Test in Patient with Rheumatologic Disease

Abstract

The aim of this study is to evaluate the possibility of a positive PPD test after treatment with biologic drugs in patients with the rheumatologic disease who had a previous negative PPD test before the start of treatment.

Methods & Materials: This study was performed as a prospective cohort study and patients with the rheumatologic disease under treatment with biologic drugs in the teaching center of Emam Reza hospital of Tabriz were studied during one and half year. After selecting patients, PPD test was performed and those with positive results before the initiation of treatment with biologic drugs were excluded and those with negative PPD test were included. Two weeks after the start of treatment, the PPD test was repeated in those included patients, and if the PPD test was positive, the features of induration and the type of administered drug were completely recorded and the study was continued with PPD negative patients and every four weeks PPD test performed until the patient become PPD positive or four months after the initiation of the first dose of drug. Then, the data was collected and was analyzed using SPSS v 22.

Results: Among 50 patients in this study, 28 patients (56%) were male and 22 (44%) were female. Mean age was 31.2 (+/- 6.55) years. Thirty-three patients (66%) had ankylosing spondylitis and 17 patients (34%) had rheumatoid arthritis. During this study all patients who had a negative PPD test received infliximab. Then, in patients follow up, before administration of the second dose of infliximab, PPD was repeated that one of the patients (2%) had a positive PPD test. During the remaining follow-ups, PPD test was repeated before the third and fourth drug administrations but none of the patients had a positive PPD test.