Assessment of neuropathic pain, functional activity limitation and quality of life of people affected by leprosy in an endemic area in Northeast Brazil: a cross-sectional study.

BACKGROUND: This study investigated the prevalence of neuropathic pain (NP) among people affected by leprosy and its effects on functional limitation and health-related quality of life (HRQoL) in an endemic area in Northeast Brazil. METHODS: This is a cross-sectional study of 122 leprosy patients. Functional limitation and HRQoL were assessed using the Screening of Activity Limitation and Safety Awareness (SALSA) and WHO Quality-of-Life (WHOQoL-BREF) scales, respectively. Participants were assessed for the presence of pain and completed the Douleur Neuropathique 4 and the Brief Pain Inventory scales. RESULTS: The prevalence of NP was 59%. Participants with NP had higher SALSA scores than those without pain (median; IQR: 42; 32-49.5 vs 27.5; 24-34; p=0.002). Increasing SALSA scores were related to decreasing WHOQoL-BREF scores in the physical (r=-0.54; p<0.001), psychological (r=-0.33; p=0.002) and environmental (r=-0.22; p=0.01) domains, but not in the social domain (r=-0.14; p=0.10). Individuals with NP had the lowest scores in all domains compared with individuals without pain. CONCLUSIONS: Appropriate tools and training of clinicians for diagnosing NP in leprosy patients are necessary for their appropriate management and better HRQoL outcomes.

Clinical and electrophysiological characteristics of neuropathic pain in leprosy patients: A prospective cross-sectional study.

Introduction Neuropathic pain is a common and disabling late complication of leprosy. We investigated the clinical and electrophysiological characteristics of neuropathic pain in leprosy patients by evaluating nerve conduction, sympathetic skin response (SSR) and A-waves. Methods Twenty one leprosy patients with neuropathic pain validated by the Douleur Neuropathique en 4 (DN4)Questionnaire were selected for study. Pain intensity was measured by the visual analog scale. Demographic and clinical data were collected for all patients. Clinical data included appraisal of the median, ulnar, radial, tibial and common peroneal nerves, assessment of the sympathetic skin response and conventional electrophysiological recordings. Results Among all electroneuromyographic presentations, multifocal mononeuropathy was still the most prevalent. Sensory loss was observed more frequently than motor deficits. As most patients presented advanced clinical forms of leprosy and were under treatment, this high mean was found and the ulnar nerve was most frequently affected. The sympathetic skin response was absent in 16 patients. Higher DN4 Questionnaire scores were observed in women and in those receiving corticosteroid therapy. These inferences are possible to be made, but our study's limitations don't allow us to be certain about it. The statistical significance found only permits us to evidence what we related on the textual part of the study. Limitations The small number of patients studied, the lack of sophisticated diagnostic methods for leprosy, as well as the difficulties in assessing nerve conduction were the main limitations of this study. Conclusion The neurophysiological and clinical findings in leprous neuropathy were modest despite the conspicuous neuropathic pain. Although electrophysiological studies are a vital tool to verify nerve damage, variations in the clinical presentation of leprosy neuropathic pain render the diagnosis challenging. Further studies are needed to describe the neurophysiological evolution of this disease.

Assessment of neuropathic pain in leprosy patients with relapse or treatment failure by infrared thermography: A cross-sectional study.

BACKGROUND: Neuropathic pain (NP) is one of the main complications of leprosy, and its management is challenging. Infrared thermography (IRT) has been shown to be effective in the evaluation of peripheral autonomic function resulting from microcirculation flow changes in painful syndromes. This study used IRT to map the skin temperature on the hands and feet of leprosy patients with NP. METHODOLOGY/PRINCIPAL FINDINGS: This cross-sectional study included 20 controls and 55 leprosy patients, distributed into 29 with NP (PWP) and 26 without NP (PNP). Thermal images of the hands and feet were captured with infrared camera and clinical evaluations were performed. Electroneuromyography (ENMG) was used as a complementary neurological exam. Instruments used for the NP diagnosis were visual analog pain scale (VAS), Douleur Neuropathic en 4 questions (DN4), and simplified neurological assessment protocol. The prevalence of NP was 52.7%. Pain intensity showed that 93.1% of patients with NP had moderate/severe pain. The most frequent DN4 items in individuals with NP were numbness (86.2%), tingling (86.2%) and electric shocks (82.7%). Reactional episodes type 1 were statistically significant in the PWP group. Approximately 81.3% of patients showed a predominance of multiple mononeuropathy in ENMG, 79.6% had sensory loss, and 81.4% showed some degree of disability. The average temperature in the patients' hands and feet was slightly lower than in the controls, but without a significant difference. Compared to controls, all patients showed significant temperature asymmetry in almost all points assessed on the hands, except for two palmar points and one dorsal point. In the feet, there was significant asymmetry in all points, indicating a greater involvement of the lower limbs. CONCLUSION: IRT confirmed the asymmetric pattern of leprosy neuropathy, indicating a change in the function of the autonomic nervous system, and proving to be a useful method in the approach of pain.

Cytokine Levels in Neural Pain in Leprosy.

Pain is a frequent symptom in leprosy patients. It may be predominantly nociceptive, as in neuritis, or neuropathic, due to injury or nerve dysfunction. The differential diagnosis of these two forms of pain is a challenge in clinical practice, especially because it is quite common for a patient to suffer from both types of pain. A better understanding of cytokine profile may serve as a tool in assessing patients and also help to comprehend pathophysiology of leprosy pain. Patients with leprosy and neural pain (n = 22), neuropathic pain (n = 18), neuritis (nociceptive pain) (n = 4), or no pain (n = 17), further to those with diabetic neuropathy and neuropathic pain (n = 17) were recruited at Souza Araujo Out-Patient Unit (Fiocruz, Rio de Janeiro, RJ, Brazil). Serum levels of IL1ß, IL-6, IL-10, IL-17, TNF, CCL-2/MCP-1, IFN-γ, CXCL-10/IP-10, and TGF-ß were evaluated in the different Groups. Impairment in thermal or pain sensitivity was the most frequent clinical finding (95.5%) in leprosy neuropathy patients with and without pain, but less frequent in Diabetic Group (88.2%). Previous reactional episodes have occurred in patients in the leprosy and Pain Group (p = 0.027) more often. Analysis of cytokine levels have demonstrated that the concentrations of IL-1ß, TNF, TGF-ß, and IL-17 in serum samples of patients having leprosy neuropathy in combination with neuropathic or nociceptive pain were higher when compared to the samples of leprosy neuropathy patients without pain. In addition, these cytokine levels were significantly augmented in leprosy patients with neuropathic pain in relation to those with neuropathic pain due to diabetes. IL-1ß levels are an independent variable associated with both types of pain in patients with leprosy neuropathy. IL-6 concentration was increased in both groups with pain. Moreover, CCL-2/MCP-1 and CXCL-10/IP-10 levels were higher in patients with diabetic neuropathy over those with leprosy neuropathy. In brief, IL-1ß is an independent variable related to neuropathic and nociceptive pain in patients with leprosy, and could be an important biomarker for patient follow-up. IL-6 was higher in both groups with pain (leprosy and diabetic patients), and could be a therapeutic target in pain control.

Diagnosis and impact of neuropathic pain in leprosy patients in Nepal after completion of multidrug therapy.

OBJECTIVES: Neuropathic pain (NP) can occur as a chronic complication of leprosy neuropathy. NP epidemiology and its impact on patients have not been well documented. This study investigates NP prevalence and impact in the years after patients are declared "released from treatment" (RFT) following multidrug therapy (MDT) completion. METHODS: In this cross-sectional study, 85 RFT patients were recruited within leprosy referral services in Nepal. The Douleur Neuropathique 4 Questionnaire (DN4) was used to screen for NP. Pain severity, impacts on patients' daily activities and mental health were measured by using the Brief Pain Inventory (BPI), Screening of Activity Limitation and Safety Awareness (SALSA), and General Health Questionnaire-12 (GHQ-12) respectively. RESULTS: 96% surveyed had been treated for multibacillary leprosy. 44 (52%) complained of pain of which 30 (68%) were diagnosed with NP. NP was not associated with age, gender, or presence of skin lesions or nerve symptoms at leprosy diagnosis. 70% of patients with NP had either history of or ongoing reactions and 47% had grade 2 disability. Nerve tenderness (p = 0.023) and current reactions (p = 0.018) were significant risk factors for NP. Patients with NP suffered significantly higher intensity pain (p = 0.023) and daily life interference (p = 0.003) and were more likely to have moderate to extreme daily activity limitations (p = 0.005). 13 (43%) exhibited psychological distress, and medications only reduced moderate degree (50-60%) of pain. CONCLUSIONS: In our study, 35% of RFT patients had ongoing NP. Risk factors include nerve tenderness and reaction. They suffer from more daily life interference and psychological distress. Leprosy patient care should include recognition and management of NP.

Clinical and Neurophysiological Features of Leprosy Patients with Neuropathic Pain.

Neural pain is a frequent symptom in leprosy disease. There is a paucity of data regarding neural pain diagnostics resulting in common prescriptive errors when neuritis is confused with neuropathic or mixed nociceptive-neuropathic pain. The present study identified important demographic, clinical, and neurophysiological features of 42 leprosy neuropathy patients presenting neuropathic pain (NP). During routine evaluations, patients were selected asking if they had ever experienced neural pain. Data analyses of their pain characteristics, clinical examination results, and both the Douleur Neuropathique 4 Questionnaire and Hamilton Depression Scale scores were used to classify these patients. The most common word they used to describe the sensation of pain for 25 (60%) of these patients was "burning." In the early stages of the disease and before leprosy diagnosis, 19 (45%) had already complained about NP and leprosy treatment was unable to prevent its occurrence in 15 (36%). Leprosy reactions, considered NP risk factors, occurred in 32 (76%) cases. Knowledge of typical NP characteristics could be used to develop more effective therapeutic approaches for a notoriously difficult-to-treat pain condition.

Prevalence and characteristics of neuropathic pain in leprosy patients treated years ago.

The aim of this study was to determine the prevalence of neuropathic pain, now recognized as another late complication of leprosy, and its characteristics among leprosy patients. A cross-sectional study was carried out of people treated for leprosy up to at least 5 years ago in a rural area of Ethiopia. Seventy-four patients were interviewed using the Neuropathic Pain Symptom Inventory (NPSI) questionnaire. In total, 78.9% of the patients were female with a mean age of 42.9. The mean time from initial diagnosis to the time of the study was 28.0 years, and 73.0% of patients were diagnosed over 20 years ago. Fifty-two (70.3%) reported having symptoms suggestive of neuropathic pain and the majority described the pain as burning (88.5%), electric (80.8%), stabbing (76.9%), cutting (76.9%), tingling (65.4%), squeezing (57.7%), and/or pressure (53.8%). The pain caused a severe or moderate impact on daily life in 75% and 57.7% of cases, respectively, and 92.3% suffered from disrupted sleep. Eighty percent of patients with pain (42/52) took some medication for pain relief. Neuropathic pain is common in patients treated for leprosy and in more than half of them, it causes disruption in their daily life and sleep, limiting their quality of life even more.

Prevalence and characteristics of neuropathic pain in the people affected by leprosy in China.

OBJECTIVES: To determine the prevalence and the characteristics of neuropathic pain among the people affected by leprosy in China. METHODS: People affected by leprosy in four leprosy villages were interviewed about neuropathic pain with an interviewer-administrated questionnaire. RESULTS: In a total of 275 patients with leprosy interviewed, 126 (45.8%) reported having symptoms suggestive of neuropathic pain. The pain was severe in 70 (55.5%) patients, moderate in 49 (38.9%) and mild in 7 (5.6%). Of the 126 patients with leprosy, 109 (86.5%) stated that the pain had some impact on their daily life: mild in 13 (10.3%), moderate in 45 (35.7%) and severe in 51 (40.5%). Sleep disturbance caused by pain was reported in 119 (94.4%) patients with leprosy: mild in 13 (10.3%), moderate in 51 (40.5%) and severe in 55 (43.6%). Ninety-six patients with leprosy (76.2%) reported that they had tried analgesics alone or in combination with steroids for the relief of their pain, of which 78 (81.2%) people reported that the treatment was effective. CONCLUSIONS: Neuropathic pain is not uncommon in both MB and PB patients who have completed effective antimicrobial treatment. The effectiveness of analgesics alone or in combination with steroids, in the treatment of neuropathic pain in patients with leprosy, needs to be studied.

Investigation of neuropathic pain in treated leprosy patients in Ethiopia: a cross-sectional study.

Pain can be a significant problem for treated leprosy patients. It can be nociceptive due to tissue inflammation occurring during episodes of immune mediated reactions, or neuropathic due to leprosy affecting the somatosensory system. There are sparse epidemiological data on the prevalence and impact of neuropathic pain in treated leprosy patients. Tools for assessing neuropathic pain have not been validated in leprosy. We have examined nature of pain in a cross-sectional study to determine the prevalence of neuropathic pain (NP) in 80 recently treated leprosy patients in Ethiopia. Pain and depression were evaluated using the General Health Questionnaire (GHQ-12) and the Brief Pain Inventory (BPI) questionnaire. The Douleur Neuropathique en 4 Questions (DN4) and the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) were used as screening tools for NP. Pain of any type was experienced by 60% of the patients. Pure nociceptive pain was experienced by 43%, pure NP by 11%, and mixed pain by 6%. Of the 14 patients who had NP either alone or in combination with nociceptive pain, 12 had high GHQ-12 scores, indicating possible depression. The DN4 had sensitivity and specificity of 100% and 45%, whereas the LANSS had 85% and 42%, respectively. This is the first study to differentiate nociceptive from NP in leprosy patients. The prevalence of NP is high in recently treated Ethiopian leprosy patients. We have validated the use of DN4 in leprosy and it is easier to use than LANSS. Depression is a common co-morbidity in patients with NP. The high prevalence and morbidity of NP in treated leprosy patients warrant clinical trials to assess the efficacy of pain therapies for leprosy-associated NP.

Neuropathic pain and psychological morbidity in patients with treated leprosy: a cross-sectional prevalence study in Mumbai.

BACKGROUND: Neuropathic pain has been little studied in leprosy. We assessed the prevalence and clinical characteristics of neuropathic pain and the validity of the Douleur Neuropathique 4 questionnaire as a screening tool for neuropathic pain in patients with treated leprosy. The association of neuropathic pain with psychological morbidity was also evaluated. METHODOLOGY/PRINCIPAL FINDINGS: Adult patients who had completed multi-drug therapy for leprosy were recruited from several Bombay Leprosy Project clinics. Clinical neurological examination, assessment of leprosy affected skin and nerves and pain evaluation were performed for all patients. Patients completed the Douleur Neuropathique 4 and the 12-item General Health Questionnaire to identify neuropathic pain and psychological morbidity. CONCLUSIONS/SIGNIFICANCE: One hundred and one patients were recruited, and 22 (21.8%) had neuropathic pain. The main sensory symptoms were numbness (86.4%), tingling (68.2%), hypoesthesia to touch (81.2%) and pinprick (72.7%). Neuropathic pain was associated with nerve enlargement and tenderness, painful skin lesions and with psychological morbidity. The Douleur Neuropathique 4 had a sensitivity of 100% and specificity of 92% in diagnosing neuropathic pain. The Douleur Neuropathique 4 is a simple tool for the screening of neuropathic pain in leprosy patients. Psychological morbidity was detected in 15% of the patients and 41% of the patients with neuropathic pain had psychological morbidity.