Follow-up assessment of patients with Pure Neural Leprosy in a reference center in Rio de Janeiro-Brazil.

INTRODUCTION: Pure Neural Leprosy (PNL) is a rare clinical form of leprosy in which patients do not present with the classical skin lesions but have a high burden of the disability associated with the disease. Clinical characteristics and follow up of patients in PNL are still poorly described in the literature. OBJECTIVE: This paper aims to describe the clinical, electrophysiological and histopathological characteristics of PNL patients, as well as their evolution after multidrug therapy (MDT). METHODS: Fifty-two PNL patients were selected. Clinical, nerve conduction studies (NCS), histopathological and anti-PGL-1serology were evaluated. Patients were also assessed monthly during the MDT. At the end of the MDT, all of the patients had a new neurological examination and 44 were submitted to another NCS. RESULTS: Paresthesia was the complaint most frequently reported by patients, and in the neurological examination the most common pattern observed was impairment in sensory and motor examination and a mononeuropathy multiplex. Painful nerve enlargement, a classical symptom of leprosy neuropathy, was observed in a minority of patients and in the motor NCS axonal injuries, alone or in combination with demyelinating features, were the most commonly observed. 88% of the patients did not present any leprosy reaction during MDT. There was no statistically significant difference between the neurological examinations, nor the NCS pattern, performed before and after the MDT. DISCUSSION: The classical hallmarks of leprosy neuropathy are not always present in PNL making the diagnosis even more challenging. Nerve biopsy is an important tool for PNL diagnosis as it may guide therapeutic decisions. This paper highlights unique characteristics of PNL in the spectrum of leprosy in an attempt to facilitate the diagnosis and management of these patients.

Neuromuscular Ultrasound in the Assessment of Polyneuropathies and Motor Neuron Disease.

Neuromuscular ultrasound is an emerging technology for the evaluation of conditions affecting nerve and muscle, with most of the research focusing on focal neuropathies. Despite this focus, researchers have also investigated the ultrasonographic changes that occur in the nerves and muscles of those with more diffuse polyneuropathies and motor neuron diseases, and this review will detail the findings in these conditions. Specific findings are discussed in this article, but general themes will also be presented and include the following: hereditary polyneuropathies show diffuse nerve enlargement, whereas immune-mediated polyneuropathies show more patchy involvement; nerve enlargement is more profound in demyelinating than axonal polyneuropathies; and muscle changes in motor neuron diseases include heterogeneous increases in echogenicity, atrophy, readily detectable fasciculations, and increased subcutaneous tissue thickness.

Significant difference between three observers in the assessment of intraepidermal nerve fiber density in skin biopsy.

BACKGROUND: The determination of Intraepidermal Nerve Fiber Density (IENFD) in skin biopsy is a useful method for the evaluation of different types of peripheral neuropathies. To allow a reliable use of the method it is necessary to determine interobserver reliability. Previous studies dealing with this topic used limited suitable statistical methods. METHODS: In the present study three observers determined the IENFD and estimated the staining quality of the basement membrane for an adequate quantity of 120 skin biopsies (stained with indirect immunofluorescence technique) from 68 patients. More adequate statistical methods like intraclass correlation coefficient and Bland Altman Plot were chosen to estimate interobserver reliability. RESULTS: We found an unexpected significant difference in IENFD between the observers (p < 0.05) and so the results of this study are not in line with the high interobserver reliability reported before (intraclass correlation coefficient: 0.73). The Bland Altmann Plot showed a variance growing with rising mean. The difference in IENFD between the observers and the resulting low interobserver reliability is likely caused by different interpretations of the standard counting rules. There was no significant difference in IENFD between observers for biopsies with a well-defined basement membrane. Thus skin biopsies with an inexactly defined basement membrane should not be used diagnostically for the determination of IENFD. CONCLUSION: These results emphasise that standardisation of the method is extremely important and at least two observers should analyse skin biopsies with critical IENFD near the cut-off values.

Toxicological assessment of isomeric pesticides: a strategy for testing of chiral organophosphorus (OP) compounds for delayed polyneuropathy in a regulatory setting.

Many compounds, including some pesticides, contain structural centres of asymmetry, which convey the property of a type of stereoisomerism known as chirality. Such compounds can exist in two or more forms, depending on the number of chiral atoms and are termed stereoisomers or enantiomers. Stereoisomers of a particular compound can have different biological properties; one such of particular importance for toxicological evaluation, is the potential for differences in metabolic disposal of and binding of stereoisomers to molecular targets in the cell. The combination of differential metabolism of chiral organophosphorus (OP) pesticides and opposing stereoselectivity of inhibition of neuropathy target esterase (NTE) and acetylcholinesterase (AChE) can affect the value of the hen test, performed to OECD guidelines, in predicting the potential to cause organophosphate-induced delayed polyneuropathy (OPIDP) in humans. This is a mixed central and sensory and motor neuropathy. The experimental data on structural analogues of the pesticide methamidophos and the evidence for stereoselective OPIDP are reviewed and a model is given demonstrating how the properties of a chiral OP can result in the neuropathic potential not being detected by the standard hen test. A strategy for the assessment of a racemic mixture comprised of two OP enantiomers for the potential to induce OPIDP is outlined. The strategy uses information from structure activity relationships (SAR), in vitro tests and in vivo tests to allow risk assessment decisions to be made. It is suggested that the potential for stereoselective toxicity of pesticides should be routinely considered in regulatory assessments.

Quantitative assessment of the innervation of epineurial arteries in the peripheral nerve by immunofluorescence: differences between controls and patients with peripheral arterial disease.

The peripheral nerve is supplied by the vasa nervorum. The epi- and perineurial vessels are innervated by an autonomic plexus, which plays a role in regulation of the endoneurial blood flow. This innervation is decreased in diabetes and alcohol polyneuropathy and seems to precede the development of diabetic polyneuropathy. A decreased innervation may therefore play a role in the development of polyneuropathy. In peripheral arterial disease (PAD) clinical and morphological features are present, related to severity of ischemia. To investigate the innervation of the vasa nervorum in severe ischemia, we performed immunofluorescence staining with the general neural marker protein gene product (PGP) 9.5 in whole mount preparations of epineurial vessels of nine sural nerves taken from patients with legs amputated because of severe PAD (59+/-15 years, mean +/- SD) and ten age-matched controls (61+/-24 years). In patients with PAD the nerve density of the perivascular plexus was decreased in comparison with controls (mean intercept density/mm +/- SD) 26.0+/-6.9 in PAD and 39.9+/-10.7 in controls, area% 6.0+/-1.6 in PAD and 9.9+/-2.6 in controls, both P<0.01, t-test). A decreased perivascular plexus may result in a diminished regulation of the endoneurial blood flow in patients with severe PAD.