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

ABSTRACT Neural leprosy, which is characterized by nerve involvement without visible skin lesions, presents a diagnostic challenge. This case report examined the significance of diverse diagnostic modalities in the identification of pure neural leprosy. A 28-year-old patient with symptoms of edema, pain, paresthesia, and diminished sensitivity in the lower limbs underwent various tests. A stilt skin smear yielded negative results on bacilloscopy, whereas a Fast ML Flow leprosy test and electroneuromyography supported the diagnosis. This discussion highlights the importance of accessible methods for early investigation. This study emphasizes the multidisciplinary approach and value of the Fast ML Flow leprosy test and electroneuromyography for diagnosing neural leprosy.

Bacilloscopy and polymerase chain reaction of slit-skin smears and anti-phenolic glycolipid-I serology for Hansen's disease diagnosis.

The bacilloscopy of the slit-skin smear (SSS) is the exclusive laboratory test associated with dermato-neurological evaluation for Hansen's disease (HD) diagnosis; however, it is negative in the majority of PB or primary neural forms. Thus, a PCR technique involving different sequences and target genes has been performed with an aim to increase the sensitivity and specificity of M. leprae identification, especially in patients with low bacillary loads. Additionally, serological assays based on antibody response reflect infection levels and indicate that this could be a simpler, less invasive technique for estimating M. leprae exposure. Serological tests and PCR have been shown to be more sensitive and accurate than the SSS. Our study aimed to measure accuracy and performance among the SSS and PCR of dermal scrapings stored on filter paper and APGL-I serology for diagnosis in HD. A cross-sectional study analyzing the medical records (n = 345) of an HD outpatient-dermatology clinic from 2014 to 2021 was conducted. Accuracy performance parameters, correlation, and concordance were used to assess the value among the SSS, PCR, and APGL-I exams in HD. The SSS presented 24.5% sensitivity, 100% specificity, 37.4% accuracy, and the lowest negative predictive value (21.5%). The PCR assay had 41, 100, and 51% sensitivity, specificity, and accuracy, respectively. PCR and APGL-I serology increased the detection of HD cases by 16 and 20.6%, respectively. PCR was positive in 51.3% of patients when the SSS was negative. The SSS obtained moderate concordance with PCR [k-value: 0.43 (CI: 0.33-0.55)] and APGL-I [k-value: 0.41 (CI: 0.31-0.53)]. A moderate positive correlation was found between the APGL-I index and the bacillary index (r = 0.53; P < 0.0001). Thus, the use of the SSS is a low sensitivity and accuracy method due to its low performance in HD detection. The use of PCR and serological tests allows for a more sensitive and accurate diagnosis of patients.

Hanseníase em gêmeos de 3 anos em Mato Grosso, Brasil: a importância da baciloscopia no diagnóstico / Leprosy in 3-year-old twin children in Mato Grosso, Brazil: the importance of bacilloscopy in the diagnosis

Introdução: o diagnóstico clínico da hanseníase em crianças é particularmente difícil. Relato de Caso: crianças gêmeas bivitelinas, com três anos de idade, eram contactantes de pai com hanseníase Virchowiana. Os dois pacientes têm lesões cutâneas bem definidas e irregulares, anteriormente tratadas como micoses e uma cicatriz de BCG. Foram confirmados positivos para Mycobacterium por análise histopatológica da pele. Discussão: especialmente, com menos de cinco anos, os diagnósticos de hanseníase são raros e difíceis porque simulam outras doenças. Esses diagnósticos são alarmes epidemiológicos para áreas endêmicas e mostram a importância dos sintomas em crianças e o rastreamento nos contactantes dos pacientes.

Introduction: the clinical diagnosis of leprosy in children is particularly difficult. Case Report: fraternal twins, three years old, were in contact with a father with Virchowian leprosy. Both patients have well-defined and irregular skin lesions previously treated as mycoses and a BCG scar. They were confirmed positive for Mycobacterium by histopathological analysis of the skin. Discussion:especially, with less than five years, leprosy diagnoses are rare and difficult because they simulate other diseases. These diagnoses are epidemiological alarms for endemic areas and show the importance of symptoms in children and tracking of patients' contacts.

Classification and general aspects of leprosy

Leprosy is a chronic infectious disease whose etiological agent is Mycobacterium leprae. Recently, Mycobacterium lepromatosis is also implicated as a causative agent and has been identified in different forms of the disesase. Leprosy is a comples disease from a clinical histopathological, and molecular point of view. The wide complex disease from a clinical, histopathological characteristics observed throughout the disease spectrum and reactions render it a challenging disease in clinical and pathological practice. This chapter discusses the main aspects of the disease and its hispathological classification. An important approach to the bacilloscopic examination, which is fundamental for the histopathological classification of the disease, showing its quantitative and qualitative aspects, is discussed. the various photographic panels demonstrate the bacillus' ability to parasitize different types of tissues and cells of the skin and other organs of the human body...

Indeterminate leprosy

Leprosy in its determinate from (I) is a clinical presentation of the disease preceding the forms described in the Ridley and Jopling (R & J) classification and any other special forms of leprosy or the reactions. In this chapter, the histopathological and bacilloscopic characteristics of the I form of leprosy are described, and the main differential diagnoses are discussed. The histopathological criteria that distinguish the I form from the other forms of leprosy and the reaction processes that may occur during the disease course are also discussed. The identification of the histopathological characteristics of I leprosy is of great importance with respect to the selection of the treatment. I leprosy should not be confused with other forms of leprosy, especially the multibacillary forms, wich require more prolonged treatment and wich can develop reaction phenomena, causing permanent sequelae.

Peripheral nerve biopsy: a tool still needed in the early diagnosis of neural leprosy?

BACKGROUND: The early recognition of neural impairment in leprosy, especially in primary neural forms, represents a challenge in clinical practice and a peripheral nerve biopsy may be required for diagnostic confirmation. This study aims to characterize the epidemiological, clinical, electroneuromyographic, laboratory and histopathological aspects of patients undergoing peripheral nerve biopsy during investigation of primary neural cases in leprosy. METHODS: A total of 104 patients with peripheral neuropathy who were referred to a national reference centre for leprosy were biopsied from 2014 to 2018. All cases underwent clinical, laboratory, histopathological and electroneuromyographic evaluations. RESULTS: Of 104 biopsied patients, leprosy was confirmed in 89.4% (93/104). The biopsied nerves were the ulnar (67.8% [63/93]), superficial fibular (21.5% [20/93]), sural (8.6% [8/93]), radial (1.1% [1/93]) and deep fibular (1.1% [1/93]). Twenty-nine percent (27/93) presented histopathological abnormalities and 4.4% (4/93) presented acid-fast bacilli. Nerve and superjacent skin quantitative polymerase chain reaction were positive in 49.5% (46/93) and 24.8% (23/93) of cases, respectively. Patients with multiple mononeuropathy had a higher frequency of histopathological abnormalities (p=0.0077). CONCLUSIONS: This study reinforces peripheral nerve biopsy's role as an important tool in the investigation of primary neural cases, contributing to the early diagnosis and also reducing diagnostic errors and the need for empirical treatment.

Análise de tendência histórica da evolução da hanseníase em Santa Catarina no período de 2001-2015 / Analysis of the histórical trend of leprosy evolution in a state in southern Brazil in the period 2001-2015

Introdução: A Hanseníase é uma doença infecciosa crônica causada pelo Mycobacterium leprae, também chamado de bacilo de Hansen. Em Santa Catarina, atualmente há baixos índices de morbidade decorrente de ações efetivas de combate à doença nos últimos vinte anos. Porém existem poucos estudos publicados que avaliem esses indicadores no estado em geral. Objetivos: Avaliar aspectos sociodemográficos e epidemiológicos da evolução da hanseníase no Estado de Santa Catarina, entre os anos de 2001 e 2015. Métodos: Estudo observacional do tipo ecológico, descritivo e analítico. Foram estudadas as características clínicas e epidemiológicas dos pacientes diagnosticados e notificados com hanseníase em Santa Catarina no período de 2001 a 2015. Resultados: No período avaliado, 3605 casos da doença foram notificados no estado. Dentre esses, a maior taxa de incidência da doença ocorreu em 2004, de 5,03/100.000 hab, e a menor em 2015, de 2,42/100.000 hab. A macrorregião que apresentou maior número de casos novos foi o Extremo Oeste, seguida do Planalto Norte. A maioria dos pacientes era do sexo masculino, correspondendo 57,82% dos casos e a faixa etária mais acometida foi dos 40 aos 59 anos de idade. Conclusão: É fundamental que medidas como a implementação de programas e estratégias de educação em saúde, sejam mantidas e aperfeiçoadas afim de reduzir cada vez mais as taxas de incidência da doença no Brasil e preconizar o seu diagnóstico precoce para se evitar o surgimento de possíveis sequelas e complicações.

Introduction: Leprosy is a chronic infectious disease caused by Mycobacterium leprae, also called Hansen's bacillus. In Santa Catarina, there are currently low morbidity rates due to effective actions to combat the disease in the last twenty years. However, there are few published studies that evaluate these indicators in the state in general. Objectives: To evaluate sociodemographic and epidemiological aspects of leprosy evolution in the State of Santa Catarina, between 2001 and 2015. Methods: Observational ecological, descriptive and analytical study. The clinical and epidemiological characteristics of the patients diagnosed and reported with leprosy in Santa Catarina from 2001 to 2015 were studied. Results: During the period evaluated, 3605 cases of the disease were reported in the state. Among these, the highest incidence rate of the disease occurred in 2004, from 5.03 / 100,000 inhabitants, and the lowest in 2015, from 2.42 / 100,000 inhabitants. The macro-region that presented the highest number of new cases was the Far West, followed by the North Plateau. The majority of the patients were male, 57.82% of the cases and the most affected age group was 40 to 59 years of age. Conclusion: It is fundamental that measures such as the implementation of health education programs and strategies be maintained and improved in order to reduce the incidence rates of the disease in Brazil and recommend its early diagnosis to avoid the appearance of possible sequelae and complications.

qPCR detection of Mycobacterium leprae in biopsies and slit skin smear of different leprosy clinical forms

Abstract Leprosy, whose etiological agent is Mycobacterium leprae, is a chronic infectious disease that mainly affects the skin and peripheral nervous system. The diagnosis of leprosy is based on clinical evaluation, whereas histopathological analysis and bacilloscopy are complementary diagnostic tools. Quantitative PCR (qPCR), a current useful tool for diagnosis of infectious diseases, has been used to detect several pathogens including Mycobacterium leprae. The validation of this technique in a robust set of samples comprising the different clinical forms of leprosy is still necessary. Thus, in this study samples from 126 skin biopsies (collected from patients on all clinical forms and reactional states of leprosy) and 25 slit skin smear of leprosy patients were comparatively analyzed by qPCR (performed with primers for the RLEP region of M. leprae DNA) and routine bacilloscopy performed in histological sections or in slit skin smear. Considering clinical diagnostic as the gold standard, 84.9% of the leprosy patients were qPCR positive in skin biopsies, resulting in 84.92% sensitivity, with 84.92 and 61.22% positive (PPV) and negative (NPV) predictive values, respectively. Concerning bacilloscopy of histological sections (BI/H), the sensitivity was 80.15% and the PPV and NPV were 80.15 and 44.44%, respectively. The concordance between qPCR and BI/H was 87.30%. Regarding the slit skin smear, 84% of the samples tested positive in the qPCR. Additionally, qPCR showed 100% specificity, since all samples from different mycobacteria, from healthy individuals, and from other granulomatous diseases presented negative results. In conclusion, the qPCR technique for detection of M. leprae using RLEP primers proved to be specific and sensitive, and qPCR can be used as a complementary test to diagnose leprosy irrespective of the clinical form of disease.

qPCR detection of Mycobacterium leprae in biopsies and slit skin smear of different leprosy clinical forms.

Leprosy, whose etiological agent is Mycobacterium leprae, is a chronic infectious disease that mainly affects the skin and peripheral nervous system. The diagnosis of leprosy is based on clinical evaluation, whereas histopathological analysis and bacilloscopy are complementary diagnostic tools. Quantitative PCR (qPCR), a current useful tool for diagnosis of infectious diseases, has been used to detect several pathogens including Mycobacterium leprae. The validation of this technique in a robust set of samples comprising the different clinical forms of leprosy is still necessary. Thus, in this study samples from 126 skin biopsies (collected from patients on all clinical forms and reactional states of leprosy) and 25 slit skin smear of leprosy patients were comparatively analyzed by qPCR (performed with primers for the RLEP region of M. leprae DNA) and routine bacilloscopy performed in histological sections or in slit skin smear. Considering clinical diagnostic as the gold standard, 84.9% of the leprosy patients were qPCR positive in skin biopsies, resulting in 84.92% sensitivity, with 84.92 and 61.22% positive (PPV) and negative (NPV) predictive values, respectively. Concerning bacilloscopy of histological sections (BI/H), the sensitivity was 80.15% and the PPV and NPV were 80.15 and 44.44%, respectively. The concordance between qPCR and BI/H was 87.30%. Regarding the slit skin smear, 84% of the samples tested positive in the qPCR. Additionally, qPCR showed 100% specificity, since all samples from different mycobacteria, from healthy individuals, and from other granulomatous diseases presented negative results. In conclusion, the qPCR technique for detection of M. leprae using RLEP primers proved to be specific and sensitive, and qPCR can be used as a complementary test to diagnose leprosy irrespective of the clinical form of disease.

A influência do teste sorológico ML Flow na classificação da hanseníase / The influence of ML Flow test in leprosy classification

Estudo descritivo e exploratório correlacionando o ML Flow, a baciloscopia e a classificação em paucibacilar (PB) e multibacilar (MB), envolveu 1.041 casos novos com hanseníase em 13 municípios de Minas Gerais, de outubro de 2002 a março de 2004. A concordância entre o ML Flow e a classificação pelo número de lesões cutâneas e a baciloscopia foi moderada (Kappa:0,51 e 0,48, respectivamente) e, substancial (Kappa:0,77) com a classificação final. De janeiro de 2000 a março de 2004, a proporção de casos novos MB no Estado, passou de 78,1 para 65,8%. A queda no percentual de MB foi maior nos serviços participantes da pesquisa ML Flow (73,1 para 53,3%). A diferença de PB e MB nos serviços participantes e não participantes, de janeiro a março de 2004, foi estatisticamente significativa, indicando implicação direta e benéfica no tratamento e no controle da endemia em Minas Gerais.

This is a descriptive, exploratory study correlating ML Flow, bacilloscopy and classification of paucibacillary (PB) and multibacillary (MB), involving 1,041 new leprosy cases in 13 municipalities of Minas Gerais State, from October 2002 to March 2004. Agreement between ML Flow and the classification of the number of skin lesions and bacilloscopy was moderate (K:0.51 and K:0.48, respectively); and substantial for final classification (K:0.77). From January 2000 to March 2004, the proportion of new MB cases in Minas Gerais decreased from 78.1 to 65.8%. The reduction in the percentage of MB cases was higher in health centers that participated in the ML Flow study (73.1% to 53.3%). The difference between PB and MB in the participating and non-participating health centers from January to March 2004 was statistically significant. Implementation of the ML Flow test influenced the classification of patients, suggesting a direct and beneficial impact on patient treatment and the control of the leprosy endemic in Minas Gerais, Brazil.

Fatores de risco para a soropositividade do ML Flow em pacientes com hanseníase / Risk factors for ML Flow seropositivity in leprosy patients

O diagnóstico precoce da hanseníase, a correta classificação e o estudo dos fatores de risco relacionados à soropositividade, tornam-se importantes para o tratamento do doente e controle da endemia, especialmente, quando a responsabilidade pelo atendimento desses pacientes está sendo absorvida pelos serviços de atenção básica. Estudo descritivo e exploratório utilizando regressão logística avaliou a associação das variáveis: sexo, idade, modo de detecção, número de lesões cutâneas e de nervos acometidos, grau de incapacidade, baciloscopia, com o resultado do teste sorológico ML Flow, em 1.072 casos novos com hanseníase em 13 municípios de Minas Gerais. A soropositividade (50,7%) estava estatisticamente associada aos pacientes com 15 anos ou mais de idade (OR:2,6), mais de cinco lesões cutâneas (OR:7,5), mais de um nervo acometido (OR:2,4) e com baciloscopia positiva (OR:5,5 para IB<2 e OR:191,2 para IB>2), colaborando, assim, com a classificação e o tratamento adequados dos doentes.

The early diagnosis of leprosy, its correct classification and the risk factors related to seropositivity have become important for patient treatment and disease control, especially where the responsibility for treatment has been transferred to basic health care centers. This descriptive, exploratory study using logistic regression was undertaken to evaluate the association between the variables of sex, age, mode of detection, number of skin lesions and affected nerves, disability grade and bacilloscopy with the results of the ML Flow serological test in 1,072 new leprosy cases in 13 municipalities in Minas Gerais State. Seropositivity (50.7%) was statistically associated with patients 15 years-old or over (OR:2.6) and those with more than five skin lesions (OR:7.5), more than one affected nerve (OR:2.4) and a positive bacilloscopic index (OR:5.5 for 02), thus contributing to the appropriate classification and treatment of patients.