The Correlation of Semmes–Weinstein Monofilament Test with the Level of P-75 Neurotrophin as Marker of Nerve Damage in Leprosy

INTRODUCTION: Leprosy is a chronic infectious disease caused by Mycobacterium leprae that causes damage to the peripheral nerve, particularly Schwann cells. Treatment is useful only to kill bacteria but not to recover peripheral nerve damage. However, early detection of peripheral nerve damage is necessary. We examine P-75 neurotrophin (P75(NTR)) as an indicator of peripheral nerve damage in leprosy with the Semmes–Weinstein monofilament (SWM) test as the comparison. METHODS: This study uses a quantitative analytic observational study approach with cross-sectional design, conducted at Kediri Leprosy Hospital, Malang, East Java, Indonesia. All leprosy patients had a clinical examination and bacterial index to classify leprosy and then the SWM test to examine the presence of neuropathy in the palms and feet. P75(NTR) examination uses venous blood samples. An independent t-test was used to compare the SWM and P75(NTR) scores based on the type of leprosy, and then the Spearman correlation test was used to determine the correlation between SWM scores and P75(NTR) levels. RESULTS: In this study, SWM scores on the soles of the foot and palms and the P75(NTR) levels were higher in the PB group compared with MB (p<0.05). Also, a significant positive correlation was found between P75(NTR) and the SWM scores on the palms of the hand (r=0.864; p=0.000) and the soles of the foot (r=0.864; p=0.000). CONCLUSION: There is a strong positive correlation between P75(NTR) levels and SWM scores, so P75(NTR) levels are very likely to be a marker of neuropathy in leprosy, but further studies are still needed to examine the specific role of these biomarkers.