Use of peripheral sensibility and intrinsic muscle dysfunction of hands and feet in household contacts of patients as a screening test for early diagnosis of leprosy in two endemic areas of Colombia

Abstract

Leprosy affects peripheral nerves and causes disability. Colombia has a high grade 2 disability rate among new leprosy cases, indicating late diagnosis. An early and economic screening method for leprosy is required in endemic countries. In this study, sensibility and intrinsic muscle function of hands and feet were examined by Semmes Weinstein Monofilament (SWM) testing, Froment’s and Paper Grip Test (PGT) in 20 leprosy patients, 24 household contacts (HHC), and 59 controls from different townships in Colombia. We compared thresholds for hand and foot (heaviest detected filament) and nerve thresholds (heaviest detected filament per innervated area). Excluded participants were those with other causes of peripheral neuropathy, ages below 18 and above 65. Patients had significantly higher SWM thresholds and more intrinsic muscle dysfunction than controls for all extremities and nerves (P ≤ 0.004). HHC had significantly higher thresholds than controls in left hands and both feet (P < 0.001). The frequency of a positive Froment’s test was higher in HHC than in controls (P = 0.037). Follow-up of HHC will investigate if the higher SWM thresholds are due to leprosy. SWM testing is an economic method which could easily be implemented and possibly assist in detecting new leprosy cases among HHC in the field.