Diagnostic usefulness of triple biopsies (Skin, Muscle and Nerve) in clinically suspected cases of vasculitis in a tertiary care hospital in Gujarat

Introduction: The term vasculitis refers to a heterogeneous group of diseases, all characterized by inflammation and destruction of blood vessel walls leading to ischemic, thrombotic, and hemorrhagic damage to tissues of central and peripheral nervous system. The main indication for triple biopsy (skin, muscle and nerve) is to rule out peripheral vasculitis neuropathy. However, the drawback is that any systemic inflammatory process may show changes in a skin biopsy and hence these changes need to be interpreted with caution. The aim of this study is to establish the diagnostic yield and the usefulness of the triple biopsies in clinically suspected cases of vasculitis. Material and Methods: The present study was conducted in the Department of General Pathology, SBKS MI & RC, Vadodara over a period of one year (1/1/2022 to 31/12/2022). All the clinically suspected cases of vasculitis received at OPD were included in the study. Any case with either muscle, nerve or skin biopsy reported as inadequate were excluded from the study. Results: On evaluation the usefulness of triple biopsies for vasculitis, we found a very low diagnostic yield with only 3.3% of peripheral nerve biopsy and 0.8% of muscle and nerve biopsy showed definite vasculitis. In case of suspected peripheral/systemic vasculitic neuropathy, nerve biopsy was sufficient in the majority of case and has the diagnostic armamentarium for the evaluation of vasculitis. Conclusion: In conclusion, nerve biopsies provide the best yield for the diagnosis of vasculitis, as opposed to muscle and skin biopsies. The role of triple biopsies as a routine protocol for the evaluation of vasculitis is questionable.

Hereditary neuropathies: Genetics and utility of nerve biopsy

Peripheral neuropathy is one of the most common neurological conditions of the nervous system. Hereditary neuropathies (HNs) form an important group with varying degrees of severity, causing a significant disease burden. Accurate diagnosis is essential for management, counseling, and preventing unnecessary extended workups for acquired etiologies and inappropriate treatment. Several hereditary neuropathies have characteristic or diagnostic histologic findings; however, in the era of molecular diagnostics, the role of nerve biopsy in the diagnosis of hereditary neuropathy has reduced significantly. Nevertheless, in sporadic cases, cases without a clear family history, clinical mimics, cases with rare mutations, and genetic variants of unknown significance, a nerve biopsy can confirm the diagnosis, provide an unexpected diagnosis, or direct a targeted molecular testing. HN may be non-syndromic, affecting predominantly the peripheral nervous system or syndromic where it is a part of more widespread neurological or multisystem involvement. This review summarizes the microscopic pathological features in a nerve biopsy in some of the more commonly encountered inherited peripheral neuropathies highlighting their utility in selected cases.

Recent advances in the diagnosis of immune mediated demyelinating neuropathies

Inflammatory neuropathies are a group of acquired neuropathies which could be due to autoimmune, infectious, paraneoplastic, or paraproteinemic etiology. The etiological diagnosis of inflammatory neuropathy is not simple, and often requires combination of clinical, electrophysiological, and histopathological findings to arrive at a precise diagnosis which is important for management of the disorder. Whereas there are comprehensive and sensitive panel of serological tests available for diagnosis of the infectious, paraneoplastic, paraproteinemic neuropathies, the diagnosis of immune-mediated demyelinating neuropathies remain a considerable challenge as there is both clinical and pathological overlap. Newer non-invasive methodologies such as high-resolution ultrasound, magnetic resonance imaging (MRI), and importantly, serological testing for antibodies are emerging, and it is essential for the practicing pathologist to be up-to-date with emerging modalities. In this review, we focus on the approach to diagnosis of immune-mediated demyelinating neuropathies.

Tissue-Clearing Technique and Cutaneous Nerve Biopsies: Quantification of the Intraepidermal Nerve-Fiber Density Using Active Clarity Technique-Pressure Related Efficient and Stable Transfer of Macromolecules Into Organs

BACKGROUND AND PURPOSE: Cutaneous nerve biopsies based on two-dimensional analysis have been regarded as a creditable assessment tool for diagnosing peripheral neuropathies. However, advancements in methodological imaging are required for the analysis of intact structures of peripheral nerve fibers. A tissue-clearing and labeling technique facilitates three-dimensional imaging of internal structures in unsectioned, whole biological tissues without excessive time or labor costs. We sought to establish whether a tissue-clearing and labeling technique could be used for the diagnostic evaluation of peripheral neuropathies. METHODS: Five healthy individuals and four patients with small-fiber neuropathy (SFN) and postherpetic neuralgia (PHN) were prospectively enrolled. The conventional methods of indirect immunofluorescence (IF) and bright-field immunohistochemistry (IHC) were adopted in addition to the tissue-clearing and labeling method called active clarity technique-pressure related efficient and stable transfer of macromolecules into organs (ACT-PRESTO) to quantify the intraepidermal nerve-fiber density (IENFD). RESULTS: The mean IENFD values obtained by IF, bright-field IHC, and ACT-PRESTO in the healthy control group were 6.54, 6.44, and 90.19 fibers/mm², respectively; the corresponding values in the patients with SFN were 1.99, 2.32, and 48.12 fibers/mm², respectively, and 3.06, 2.87, and 47.21 fibers/mm², respectively, in the patients with PHN. CONCLUSIONS: This study has shown that a tissue-clearing method provided not only rapid and highly reproducible three-dimensional images of cutaneous nerve fibers but also yielded reliable quantitative IENFD data. Quantification of the IENFD using a tissue-clearing and labeling technique is a promising way to improve conventional cutaneous nerve biopsies.

Peripheral neuropathy and the role of nerve biopsy: A revisit

Background: Nerve biopsy has been widely used to investigate patients with peripheral neuropathy and in many centers, it is still a part of the diagnostic armamentarium. In this study, the histopathological spectrum of the nerve biopsies received is being revisited to analyze the various clinical and pathologic features and also to assess their relevance. Materials and Methods: Retrospective analysis of the data retrieved was done for 74 cases of nerve biopsies. Results: On the basis of the data and histopathological features, broad diagnoses were obtained in 52 cases and further categorized into biopsies being supportive for patient management (including acute and chronic axonopathies and demyelinating neuropathies) and biopsies considered essential for patient management (including vasculitic neuropathies, leprous neuropathies, hereditary neuropathies, and chronic inflammatory demyelinating neuropathies). Nine nerve biopsies did not show any abnormal histopathological features, while 13 nerve biopsies were found to be inadequate for diagnosis, both these groups were categorized as noncontributory. Conclusion: With advanced nerve conduction studies available, nerve biopsy is losing its relevance. However, in our experience, nerve biopsy did complement the clinical findings and nerve conduction studies, with which a close correlation is required to make the histopathology of nerve biopsy more relevant in terms of guiding further specific workup and management.

Neuropatía vasculítica no sistémica: revisión de caso / Non-systemic vasculitic neuropathy: case review / Neuropatia vasculítica não sistêmica: revisão de caso

Resumen La neuropatía vasculítica no sistémica es una condición poco común, caracterizada por el compromiso aislado del sistema nervioso periférico a causa de la infiltración celular en el lecho vascular encargado de su irrigación. Es un término acuñado hace poco más de tres décadas y se considera una enfermedad poco descrita y subdiagnósticada. Se presenta el caso clínico de un paciente masculino de mediana edad que debuta con síntomas progresivos de predominio motor en miembros inferiores, quien es sometido a una serie de estudios que permiten concluir el diagnóstico. Es tratado con corticoides sistémicos, agentes citotóxicos y, por último, agentes biológicos con los que se estabilizaron los síntomas.

Summary Non-systemic vasculitic neuropathy is a rare condition characterized by the isolated involvement of the peripheral nervous system caused by cellular infiltration in the vascular bed responsible for its irrigation. It is a term which was coined a little over three decades ago and is considered a poorly described and underdiagnosed disease. Below, we present the clinical case of a middle-aged male patient who began experiencing progressive symptoms of motor predominance in the lower limbs, and who underwent a series of studies in order to conclude a diagnosis. The patient was treated with systemic corticosteroids, cytotoxic agents and, finally, biological agents which stabilized the symptoms.

Resumo A neuropatia vasculítica não sistêmica é uma condição pouco comum, caracterizada pelo compromisso isolado do sistema nervoso periférico a causa da infiltração celular no leito vascular encarregado de sua irrigação. É um termo cunhado há pouco mais de três décadas e se considera uma doença pouco descrita e subdiagnosticada. A seguir, se apresenta o caso clínico de um paciente masculino de meia idade que debuta com sintomas progressivos de predomínio motor em membros inferiores, que é submetido a uma série de estudos que permitem concluir o diagnóstico. É tratado com corticoides sistêmicos, agentes citotóxicos e, por último, agentes biológicos com o que se estabilizaram os sintomas.

Progress in research on neurolymphomatosis / 中国肿瘤临床

Neurolymphomatosis is a malignant disease that occurs primary or secondary to non-Hodgkin's lymphoma and leukemia. It is mainly caused by lymphoma cells directly infiltrating peripheral nerves, and the incidence is low. The clinical manifestations vary ac-cording to the involved nerves and mainly present as decreased strength in the muscles innervated by the affected plexus/root. It is of-ten misdiagnosed as a polyneuropathy such as Guillain-Barre syndrome or chronic inflammatory demyelinating polyneuropathy. With combined treatment using immunoglobulins or steroids, the symptoms are temporarily improved but the disease still progresses rapid-ly, eventually requiring the attention of a physician. This paper will discuss clinical reports and research on neurolymphomatosis in re-cent years from the aspects of pathogenesis, clinical manifestations, differential diagnosis, diagnostic methods, treatment, and progno-sis, and will provide a theoretical basis for clinical diagnosis and treatment.

Leprosy late-onset neuropathy: an uncommon presentation of leprosy / Neuropatia de início tardio: uma apresentação incomum da hanseníase

Clinical and pathological findings in leprosy are determined by the natural host immune response to Mycobacterium leprae. We previously described cases of painful neuropathy (PN) with no concurrent cause apart from a past history of leprosy successfully treated. Four leprosy previously treated patients who developed a PN years after multidrug therapy (MDT) are reported. The mean patient age was 52.75 years (47-64). The mean time interval of the recent neuropathy from the previous MDT was 19 years (12-26). A painful multiplex neuritis or polyneuropathy were observed respectively in two cases. Electrophysiological studies disclosed a sensory axonal neuropathy in two cases. Microvasculitis with no bacilli was seen in nerve biopsy. Neuropathic symptoms were improved with prednisone. We consider these cases as being a leprosy late-onset neuropathy (LLON) form of presentation. A delayed immune reaction could explain the late appearance of LLON.

Dados clínicos e patológicos são determinados pela resposta imune ao Mycobacterium leprae. Já haviamos descrito previamente casos de neuropatia dolorosa (ND) sem causa associada exceto história de hanseníase tratada. Relatamos agora quatro pacientes previamente tratados que desenvolveram ND anos após multidrogaterapia (MDT). A média de idade foi de 52,75 anos (47-64). O intervalo de tempo para o aparecimento da neuropatia recente, em relação à MDT prévia, foi de 19 anos (12-26). Neurite múltipla ou polineuropatia dolorosa foram observadas em dois casos. Estudos eletrofisiológicos revelaram ocorrência de neuropatia sensitiva axonal em dois casos. Em biópsia de nervos, foi observada microvasculite sem a presença de bacilos. Os sintomas neuropáticos melhoraram com o uso de prednisona. Consideramos esses casos como sendo a forma de apresentação de neuropatia da hanseníase de início tardio (NHIT). Reação imune tardia poderia explicar o aparecimento da NHIT.

Focal and multifocal diabetic neuropathies

Diabetic neuropathy is the most common neuropathy in industrialized countries, with a remarkable range of clinical manifestations. The vast majority of the patients with clinical diabetic neuropathy have a distal symmetrical form that progress following a fiber-length dependent pattern, with predominant sensory and autonomic manifestations. This pattern of neuropathy is associated with a progressive distal axonopathy. Patients are exposed to trophic changes in the feet, pains and autonomic disturbances. Less often, diabetic patients may develop focal and multifocal neuropathy that includes cranial nerve involvement, limb and truncal neuropathies. This neuropathic pattern tends to occur after 50 years of age, mostly in patients with longstanding diabetes mellitus. The LDDP does not show any trend to improvement and either relentlessly progresses or remain relatively stable over years. Conversely the focal diabetic neuropathies, which are often associated with inflammatory vasculopathy on nerve biopsies, remain self limited, sometimes after a relapsing course.

A neuropatia diabética é a mais predominante das neuropatias nos países industrializados apresentando uma gama variável de manifestações clinicas. A maioria dos pacientes com neuropatia diabética apresenta uma forma simétrica distal que progride para um padrão fibra comprimento dependente com manifestações sensitivas e autonomicas. Este tipo de neuropatia é associado com uma axonopatia distal progressiva. Os pacientes apresentam modificações tróficas nos pés, dores e distúrbios autonômicos. Menos freqüentemente os pacientes diabéticos podem desenvolver neuropatia focal e multifocal que incluem envolvimento de nervos cranianos, tronco e membros inferiores. Este padrão de neuropatia é mais freqüente em pacientes com mais de 50 anos e com longa historia de diabetes. Este tipo de neuropatia fibra-comprimento dependente não apresenta melhora, progride lentamente ou permanece estável por vários anos. As neuropatias focais que são associadas freqüentemente com vasculopatias inflamatórias nas biópsias de nervo, permanecem auto limitadas por vezes com surtos de remissão.

A Case of Hereditary Motor and Sensory Neuropathy Type III

Hereditary motor and sensory neuropathy type III, which is also known as Dejerine-Sottas disease, is a severe demyelinating polyneuropathy which presents from birth or infancy, and is sometimes presented as a hypotonic or floppy infant. The disease is inherited autosomal recessively and includes clinical findings of generalized muscle weakness and atrophy, with the greatest severity in distal limb muscles, areflexia, and sensory loss. The disease is characterized histologically by segmental demyelination, remyelination of the peripheral nerves, and onion bulb formations. We experienced a 12-month-old girl with delayed development, frequent respiratory infection and pes cavus. We report this case with a review of related literature.

A Case of Chronic Inflammatory Demyelinating Polyneuropathy in Lupas Nephritis / 대한신장학회잡지

Systemic lupus erythematosus(SLE) is a multisys-temic disease. Peripheral neuropathy occurs in about 10% of patients with SLE. Chronic inflammatory demyelinating polyneurpathy has been reported rarely in SLE. We experienced a case of chronic inflammatory polyneuropathy in lupus nephritis. 32-year-old housewife presented to chronic progressive muscle weakness and heavy proteinuria. Kidney biopsy showed compatible with lupus nephritis (WHO Class V, membranous nephropathy). Nerve conduction studies showed reduction in conduction velocity and sural nerve biopsy revealed demyeli-nating polyneuropathy. Steroid therapy led to improvement in clinical symptoms and proteinuria.

Congenital Insensitivity to Pain with Anhidrosis: Follow-up of 1 case

Congenital insensitivity to pain with anhidrosis (CIPA: a hereditary sensory and autonomic neuropathy, HSAN IV) is a rare disease characterized by the self-mutilation, bone fracture, multiple scars, osteomyelitis, joint deformities and anhidrosis. The pathophysiologic mechanism remains unknown. This is the report of a twelve years old boy who had been diagnosed as the CIPA at his age of five. Loss of unmyelinated and small myelinated nerve fibers have been noted in an abdominal skin biopsy. On follow up studies, no significant changes were noted in the clinical manifestations and in the findings of laboratory, radiologic and electrophysiologic studies when compared to the initial studies except for the minimally progressed neuropathic ankle joints. Long term follow up study including the sequential electrophysiologic examination and biopsy of nerve and muscle might be necessary to establish the natural course of the disease. Prevention of the injury should be emphasized for the good prognosis.

Diagnostic usefulness and limitations of the sural nerve biopsy

In recent years, the sural nerve biopsy has become a commonly performed procedure in the diagnostic work-up of patients with peripheral neuropathy. This paper reviews the diagnostic usefulness and limitations of this procedure. Based on 385 sural nerve biopsies, we found clinically helpful or relevant information in 45% of cases. In 24% of cases, specific diagnoses were obtained, among which vasculitic neuropathy was most common.