Serum interleukin-6 and interferon-γ in patients with leprosy

Background Leprosy is a chronic infectious disease caused by Mycobacterium leprae and manifested by an immunological and clinical outcome, ranging from borderline lepromatous and lepromatous infections to tuberculoid and borderline tuberculoid infections. Cytokines such as interleukin (IL)-6, IL-10, interferon-γ (IFN-γ), and tumor necrosis factor-α are associated with leprosy. Objective The aim was to assess IL-6 and IFN-γ in untreated patients with leprosy and compare these levels with those in healthy controls and with different parts of the disease spectrum. Patients and methods A case–control study was conducted on 90 untreated patients with leprosy and 30 healthy controls randomly selected from patients attending the Dermatology and Leprosy Hospital, Qena Governorate, Egypt. The patients were classified into tuberculoid, borderline tuberculoid, borderline-borderline, borderline lepromatous, and lepromatous (LL). IFN-γ and IL-6 were measured by enzyme-linked immunosorbent assay technique. Results IL-6 and INF-γ were significantly higher in the patients than in the control group, with P value of 0.001 and 0.002, respectively. Regarding the serum level of INF-γ in all types of leprosy, there was a statistically significantly increase in paucibacillary leprosy and a nonsignificant increase in multibacillary leprosy; on the contrary, the results showed that serum level of IL-6 was statistically significantly increased in multibacillary leprosy and nonsignificantly increased in paucibacillary leprosy. Conclusion This study concluded that INF-γ and IL-6 may have a significant role in classifying various forms of leprosy and can be used as leprosy disease markers to predict the course and the prognosis of the disease.