Early diagnosis of neural impairment in seropositive leprosy household contacts: The experience of a reference center in Brazil

Abstract

IntroductionLeprosy is an infectious disease that remains with a high number of new cases in developing countries. Household contacts have a higher risk for the development of the disease, but the neural impairment in this group is not well elucidated yet. Here, we measured the chance of occurrence of peripheral neural impairment in asymptomatic leprosy household.MethodsContacts who present anti-PGL-I IgM seropositivity, through electroneuromyography (ENMG) evaluation. We recruited 361 seropositive contacts (SPC) from 2017 to 2021, who were subjected to an extensive protocol that included clinical, molecular, and electroneuromyographic evaluations.ResultsOur data revealed a positivity of slit skin smear and skin biopsy qPCR of 35.5% (128/361) and 25.8% (93/361) respectively. The electroneuromyographic evaluation of the SPC showed neural impairment in 23.5% (85/361), with the predominance of a mononeuropathy pattern in 62.3% (53/85). Clinical neural thickening was observed in 17.5% (63/361) of seropositive contacts, but among the individuals with abnormal ENMG, only 25.9% (22/85) presented neural thickening in the clinical exam.DiscussionOurs results corroborates the need to make the approach to asymptomatic contacts in endemic countries more timely. Since leprosy in its early stages can present an indolent and subclinical evolution, serological, molecular, and neurophysiological tools are essential to break the disease transmission chain.

Description of electroneuromiographic and laboratorial findings in leprosy neuropathy, according to its clinical forms: the confirmation of a spectral disease

“…The electroneuromyographic evaluation is very important in leprosy neuropathy, as it allows the recognition of neural dysfunction even before the onset of symptoms, since sensory and motor impairment was more evident in the ENMG than in the clinical evaluation ( 5 , 19 , 36 , 37 ). Therefore, performing ENMG in patients diagnosed with leprosy is essential, as it allows not only the stratification of severity and pattern of peripheral neural impairment, but also the detection of initial forms, contributing to early diagnosis ( 38 , 39 ).…”

Neural leprosy investigation using electroneuromyography and the ML Flow rapid test: a case report

“…Electroneuromyographic evaluation revealed signs of multiple motor and sensory mononeuropathies. This test has gained prominence as an early diagnostic tool for leprosy [8][9][10][11] .…”

“…Abnormalities observed on electroneuromyography may be present in a high proportion of asymptomatic patients with leprosy. Several studies have shown that sensory nerve conduction impairment is the most frequent and earliest detected parameter in electroneuromyography evaluation [9][10][11] .…”

New insights at the interface between leprosy and immune-mediated rheumatic diseases

“…Bazan-Furini et al followed 320 household contacts of leprosy patients and concluded that anti-PGL-1 positivity could be used to identify patients at higher risk of developing leprosy ( 6 ). Santos et al in another Brazilian study, analyzed 361 contacts with positive anti-PGL-1 that were asymptomatic, identifying the mycobacterium in the PCR test of the skin biopsy in 35% of the cases and alterations in the electroneumyography in 23.5%, concluding that screening with anti-PGL-1 can be useful to identify latent cases of leprosy ( 7 ).…”