Neuropathic pain in leprosy: symptom profile characterization and comparison with neuropathic pain of other etiologies.

INTRODUCTION: Previous studies reported a high prevalence of neuropathic pain in leprosy, being especially present in "pharmacologically cured" patients. The presence of neuropathic pain in leprosy poses a supplementary burden in patient's quality of life, daily activities, and mood. OBJECTIVES: The aim of this study was to assess whether neuropathic pain in leprosy has similar symptom profile as neuropathic pain of other etiologies and to retrospectively assess the efficacy of neuropathic pain medications regularly prescribed to leprosy. METHODS: Leprosy and nonleprosy patients had their neuropathic pain characterized by the neuropathic pain symptom inventory (NPSI, ranges from 0 to 100, with 100 being the maximal neuropathic pain intensity) in a first visit. In a second visit, leprosy patients who had significant pain and received pharmacological treatment in the first evaluation were reassessed (NPSI) and had their pain profile and treatment response further characterized, including information on drugs prescribed for neuropathic pain and their respective pain relief. RESULTS: The pain characteristics based on NPSI did not significantly differ between leprosy and nonleprosy neuropathic pain patients in visit 1 after correction for multiple analyses, and cluster analyses confirmed these findings (ie, no discrimination between leprosy and nonleprosy groups; Pearson χ2 = 0.072, P = 0.788). The assessment of pain relief response and the drugs taken by each patient, linear regression analysis showed that amitriptyline, when effective, had the highest percentage of analgesic relief. CONCLUSIONS: Neuropathic pain in leprosy is as heterogeneous as neuropathic pain of other etiologies, further supporting the concept that neuropathic pain is a transetiological entity. Neuropathic pain in leprosy may respond to drugs usually used to control pain of neuropathic profile in general, and amitriptiline may constitute a potential candidate drug for future formal clinical trials aimed at controlling neuropathic pain in leprosy.

Neuropathic pain in leprosy.

Nerve impairment is a key clinical aspect of leprosy and may present the distribution of mononeuropathy or multiple nerve trunks, small cutaneous nerve fibers, and free nerve endings. The clinical range of leprosy is determined by individual cell-mediated immune response to infection that also may play a role in different types of pain syndromes in leprosy. Previous studies reported a high prevalence of neuropathic pain in leprosy. In an Ethiopian study with 48 patients, pure nociceptive pain was experienced by 43% of patients and pure neuropathic pain (NeP) by 11% of patients. In an Indian study, 21.8% of leprosy patients had pain with neuropathic characteristics. These rates underlie the need to develop tools for the early diagnosis and detection of infection and its complications, such as nerve damage and pain. In a larger sample with leprosy-associated NeP (n = 90), we have applied the Douleur Neuropathique en 4 questions (DN4) and found sensitivity = 97.1% and specificity = 57.9%. The high sensitivity of this tool in leprosy patients suggests that it could be a valuable tool to screen for neuropathic pain in this population and could be used as part of health care programs aimed at detecting, treating, and rehabilitating leprosy in endemic areas.

Neuropathic pain in leprosy patients.

The introduction of multidrug therapy by the World Health Organization has dramatically reduced the world prevalence of leprosy but the disease is still a public health problem in many countries, with a world prevalence of almost 600,000 cases in 2001. Damage to peripheral nerves is a key component of leprosy and the sensory and motor loss that follows is the basis for many of the classical features of this disease, such as skin wounds, cracks, plantar ulcers, clawed hands, drop foot, and incomplete closure of the eyelids. One of the most remarkable aspects of leprosy to lay persons and health care workers alike is that patients are reputed to feel no pain. However, neuropathic pain is arising as a major problem among leprosy patients. It can be nociceptive due to tissue inflammation, which mostly occurs during episodes of immune activation or neuropathic due to damage or dysfunction of the nervous system. This study, conducted among 358 leprosy patients, reveals a considerable prevalence of neuropathic pain and presents evidence that this common problem should be a high priority of those in charge of leprosy control programs.

Dor Crônica em Hanseníase – Um Problema de Saúde Pública? / Chronic Pain in Hansen's Disease - A Public Health Problem?

A hanseníase, ainda com taxa de detecção muito elevada no Brasil, caracteriza-se por alterações dos nervos periféricos e lesões de pele com distúrbio de sensibilidade, sendo a última um dos paradigmas para seu diagnóstico. Entretanto, o sintoma dor nesses pacientes tem sido relatado com crescente freqüência. A dor pode ser nociceptiva devido à inflamação dos tecidos (reação reversa e eritema nodoso leproso) e neuropática (por lesão anatômica e/ou funcional do sistema nervoso). Foram estudados 53 pacientes com queixas de dor para investigar suas características espaciais, temporais, descritivas, afetivas e avaliativas. Dentre eles, 73,6% já tinham completado o tratamento com PQT/OMS e 84,9% eram casos multibacilares. A localização espacial mais prevalente refere-se aos nervos ulnar e tibial. A dor em queimação é a descrição livre mais referida pelo pacientes (28,3%) e a adjetivação afetiva e avaliativa revela potencial de interferência na qualidade de vida. A dor nos portadores de hanseníase pode se apresentar, mesmo após a cura da doença, com características sensoriais, espaciais, temporais e afetivas bastante definidas e prejudiciais, que demandam controle e tratamento específico.

Neuropathic pain in leprosy: symptom profile characterization and comparison with neuropathic pain of other etiologies

Introduction: Previous studies reported a high prevalence of neuropathic pain in leprosy, being especially present in "pharmacologically cured" patients. The presence of neuropathic pain in leprosy poses a supplementary burden in patient's quality of life, daily activities, and mood.Objectives: The aim of this study was to assess whether neuropathic pain in leprosy has similar symptom profile as neuropathic pain of other etiologies and to retrospectively assess the efficacy of neuropathic pain medications regularly prescribed to leprosy. Methods: Leprosy and nonleprosy patients had their neuropathic pain characterized by the neuropathic pain symptom inventory (NPSI, ranges from 0 to 100, with 100 being the maximal neuropathic pain intensity) in a first visit. In a second visit, leprosy patients who had significant pain and received pharmacological treatment in the first evaluation were reassessed (NPSI) and had their pain profile and treatment response further characterized, including information on drugs prescribed for neuropathic pain and their respective pain relief. Results: The pain characteristics based on NPSI did not significantly differ between leprosy and nonleprosy neuropathic pain patients in visit 1 after correction for multiple analyses, and cluster analyses confirmed these findings (ie, no discrimination between leprosy and nonleprosy groups; Pearson x2 5 0.072, P 5 0.788). The assessment of pain relief response and the drugs taken by each patient, linear regression analysis showed that amitriptyline, when effective, had the highest percentage of analgesic relief. Conclusions: Neuropathic pain in leprosy is as heterogeneous as neuropathic pain of other etiologies, further supporting the concept that neuropathic pain is a transetiological entity. Neuropathic pain in leprosy may respond to drugs usually used to control pain of neuropathic profile in general, and amitriptiline may constitute a potential candidate drug for future formal clinical trials aimed at controlling neuropathic pain in leprosy.