Effect of Corticosteroid Usage Combined With Multidrug Therapy on Nerve Damage Assessed Using Nerve Conduction Studies: A Prospective Cohort Study of 365 Untreated Multibacillary Leprosy Patients

Abstract

The purpose of this study is to determine the extent of nerve involvement and to study the effect of corticosteroids combined with multidrug therapy on nerve damage in leprosy patients using sensory and motor nerve conduction studies. A cohort of 365 untreated multibacillary leprosy patients were prospectively studied using sensory and motor nerve conduction studies on upper and lower limb nerves. They were subgrouped as those to be treated with 12-week regimen of corticosteroids for reaction and/or neuritis or silent neuropathy of <6 months duration along with 12-month multidrug therapy (group A), and those with no reaction were treated with multidrug therapy only (group B). Analysis was performed using SPSS version 10.0. Significance of association was tested using chi(2) test. At registration, abnormality by nerve conduction studies was seen in 92% of patients and majority (65%) showing involvement of more than five sensory and motor nerves. Sensory nerve abnormalities were higher (52%) than motor (37%) (P < 0.001). Affection of sensory and motor nerves was higher in group A (P < 0.001). Notably, 40% nerves in group B also showed impairment at 0 month. This implies that almost all patients showed abnormal nerve conduction studies at onset regardless of reaction, proving nerve damage is more widespread than envisaged. At 18 months, overall percentile deterioration (23%) of nerves was higher than improvement (9%) (P < 0.001) indicating that corticosteroids combined with multidrug therapy failed to significantly improve the nerve status. Sensory nerve (57%) affection was significantly higher than motor (46%) (P < 0.001). Moreover, percentile deterioration of sensory nerves was higher in group A (P < 0.001) implying corticosteroids is not very efficacious in the prevention or reversal of nerve damage. Electrophysiological tests provide valuable information for detecting nerve function impairment and evaluating appropriate therapeutic regimens.

Ultrasonography of Leprosy Neuropathy: A Longitudinal Prospective Study

“…In this first prospective study investigating ultrasonographic nerve abnormalities in leprosy we found that the neural involvement may not improve after treatment, in accordance with the findings of previous clinical and electrophysiological studies [17–19,24–27]. Furthermore, US findings can worsen despite the operational classification and the presence of reactions, as demonstrated by the CSA increase in the CF nerve in PB and in patients without reactions and by the increased frequency of echogenicity abnormalities detected in the post-treatment evaluation.…”

“…One previous prospective study [17] that investigated the electrophysiological parameters of 365 MB patients who were divided in two groups (with and without reactions) revealed that deterioration of nerve function was more frequent than improvement in both groups. Similar to the findings of Capadia et al, our results revealed high frequencies of poor outcomes for CSA (up to 25%) and echogenicity (45.2%) in the patients without reactions, sometimes with greater percentages of abnormalities than patients with reactions.…”

“…There are prospective studies investigating functional impairment during and after multi-drug treatment (MDT) [17–19]; however, to our knowledge, there are no longitudinal studies investigating the evolution of nerve ultrasonographic abnormalities after MDT in leprosy patients. The purpose of this study was to investigate the evolution of US abnormalities in leprosy patients and the risk factors for poor outcomes after treatment.…”

Primary neural leprosy: systematic review

“…In this connection, nerve conduction studies (NCS) are a sensitive method for the investigation of PNL 13,28,30 (C). There is prominence of demyelinating neuropathy of the ulnar nerve at the elbow in 55.0% of the cases 34,36 (C). All these studies emphasize the asymmetric and multifocal impairments.…”

“…However, these effects did not persist after the interruption of the steroid treatment 55 (B). In a study where an initial dose of 40 mg/day was used and reduced in up to 12 months to 5 mg/day, with repetition of treatment if reactions appeared, it was observed impairment prevention and improvement of motor function during drug administration, but the sensory impairment did not show any function recovery 56 (C). The electrophysiological assessment of 24 PB PNL patients with neural loss, treated with an initial dose of 60 mg/day orally, which was progressively reduced for six months, presented significant sensory and motor improvements in the study period 29 (B).…”