Leprosy Reactions and Neuropathic Pain in Pure Neural Leprosy in a Reference Center in Rio de Janeiro – Brazil

Abstract

IntroductionLeprosy reactions are complications that can occur before, during, or after multidrug therapy (MDT) and are considered a major cause of nerve damage. Neuritis is an inflammatory process that causes nerve function impairment associated with pain and tenderness along the nerve. Neuritis can be found in both type 1 and type 2 reactions and may also be the sole manifestation of a leprosy reaction. The objective of this study is to describe the incidence of leprosy reactions and its association with neuropathic pain in pure neural leprosy (PNL) patients.MethodsWe selected 52 patients diagnosed with PNL and 67 patients with other clinical forms of leprosy. During the MDT the patients visited the clinic monthly to take their supervised dose. The patients were instructed to return immediately if any new neurological deficit or skin lesions occurred during or after the MDT.ResultsOf the PNL patients, 23.1% had a leprosy reaction during or after the MDT, while this was 59.7% for patients with the other clinical forms of leprosy. There was an association between having PNL and not having any reaction during and after the MDT, as well as having PNL and having neuritis after the MDT.There was also an association between having previous neuritis and having neuropathic pain in the other clinical forms of leprosy group, although this association was not present in the PNL group.DiscussionOur data suggest that PNL is a different form of the disease, which is immunologically more stable. In addition, PNL patients have more neuritis than the classical leprosy skin reactions. In PNL there was no association between acute neuritis and neuropathic pain, suggesting that these patients may have had silent neuritis. Understanding and identifying neuritis is essential to reduce disability and the impact on public health.

Cytokines profile in pure neural leprosy

“…PNL is still a poorly understood form of leprosy ( 9 ). Cytokines are produced as a response of the immune system to antigens ( 7 ) and, although the cytokine profile has been investigated for other forms of leprosy, few studies have evaluated cytokine levels in patients with PNL.…”

“…Type 2 leprosy reactions are mediated by antibody or immune complexes and clinically characterized by painful nodes and systemic symptoms. Neural damage and neuritis may occur in both types of leprosy reactions ( 6 , 9 ). It is still unknown whether the damage to the peripheral nerve is caused by the M. leprae itself or the inflammatory response that it causes ( 10 ).…”

“…The pure neural leprosy (PNL) is a rare form of the disease, where only neurological deficits manifest, without skin lesions ( 1 , 14 ). PNL pathophysiology is still poorly understood ( 1 , 9 , 15 ). The objective of this study is to describe the cytokine profile found in patients with PNL.…”

Hansen’s Disease: A Practical Update on a Neglected Globally Significant Infection

“…Patients present with erythema nodosum (painful subcutaneous nodules) with constitutional symptoms such as fever, fatigue, anorexia and malaise. They may also present multi-organ involvement including neurologic, testicular and joint involvement [ 20 ].…”

Systematic Review of Survival Analysis in Leprosy Studies—Including the Following Outcomes: Relapse, Impairment of Nerve Function, Reactions and Physical Disability

“…These manifestations are derived from the bacillary load and the immune response to the etiological agent, Mycobacterium leprae, which is likely to affect between 30 and 50% of leprosy patients [66,67]. The grouping was carried out according to the outcomes: leprosy reactions and nerve function impairment that are interconnected and influence the final event, physical disabilities [7,68].…”