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G Said

Publications and source records attributed to G Said.

At least 37 records · Page 2Linked to original sources
PubMed1996

Contribution of nerve biopsy findings to the diagnosis of disabling neuropathy in the elderly. A retrospective review of 100 consecutive patients.

Peripheral neuropathy is an important factor of disability in the elderly. In order to learn more on the usefulness of intensive evaluation of patients over 65 years of age with subacute or chronic disabling peripheral neuropathy, we reviewed the clinical and nerve biopsy findings of the last 100 patients of this age group who suffered from a peripheral neuropathy severe enough to justify performance of a nerve biopsy for a diagnostic or prognostic purpose. Normal nerve biopsy findings led to the diagnosis of lower motor neuron disease in three patients and pointed to lesions of the spinal roots in six other patients. Necrotizing arteritis was demonstrated in the biopsy specimens of 23 patients, and non-necrotizing vasculitis in five. In five additional patients the diagnosis of vasculitic neuropathy was kept in spite of non-contributive biopsy findings. In two diabetic patients who had a multifocal neuropathy the biopsy also revealed the presence of vasculitis. Thus 35% of the patients included in this series had one form or another of vasculitic neuropathy. Fourteen patients had a chronic inflammatory demyelinating polyneuropathy. In 11 patients the neuropathy was associated with monoclonal gammopathy, which was benign in nine and associated with malignant plasma cell dyscrasia in two. Among the six patients with diabetes mellitus, two patients who presented with a multifocal neuropathy were found to have vasculitis in the nerve specimen; in the others the biopsy was performed because of uncommonly severe pains or motor involvement due to an extremely severe diabetic neuropathy. Six patients suffered from a long-lasting disability secondary to a drug-induced neuropathy. The remaining 15% had neuropathies of different origin, including amyloidosis, lepromatous leprosy, carcinomatous neuropathy and alcoholic neuropathy. Six patients had a mild, non-progressive or slowly progressive axonopathy of unknown origin, ageing of the peripheral nervous system may have played a role in its development. Our findings show that vasculitis is an important and treatable cause of disabling neuropathy in the elderly and that the proportion of patients with severe neuropathy of unknown origin is small.

Aged↗
PubMed1996

Detection of Mycobacterium leprae in nerve lesions by the polymerase chain reaction.

A simple procedure is described for the detection of Mycobacterium leprae by the polymerase chain reaction in nerve biopsies sectioned with a cryostat and then treated with proteinase K. All samples from lepromatous leprosy patients and the majority of samples from paucibacillary cases yielded positive results. This approach may be useful for differentiating between leprosy and other inflammatory neuropathies.

Adult↗
PubMed1996

[Guillain-Barré syndrome: morphological lesions and their relations with clinical manifestations].

Acute demyelinization of the peripheral nervous system is a characteristic feature of Guillain-Barré syndrome. Lesions of the spinal roots predominate with more or less diffuse multifocal peripheral demyelinization. Inflammatory lesions of the distal peripheral nervous system are less common. Segmentary demyelinization of nerve fibers accompanying inflammatory lesions show characteristic penetration of macrophages within a normal appearing myelin sheath. The myelin on the segments concerned is rapidly destroyed by phagocytosis and removed with the macrophages. Once the debris has been removed, the axons are remyelinized after proliferation of the Schwann cells. In monophasic cases, the entire processes occurs over a 2-3 week period allowing remyelinization and rapid functional recovery. In prolonged cases, flare-ups of demyelinization, non remyelinization or damage to the axons can retard recovery. The mechanism and impact of axon damage which accompanies demyelinization at various degrees and which may predominate in certain cases, is discussed here.

Axons↗
PubMed1995

Peripheral neuropathy with necrotizing vasculitis in rheumatoid arthritis. A clinicopathologic and prognostic study of thirty-two patients.

OBJECTIVE: To examine the clinicopathologic features of the noncompressive neuropathies in rheumatoid arthritis (RA). METHODS: We studied 32 patients with RA and peripheral neuropathy whose nerve and/or muscle biopsy specimens exhibited necrotizing vasculitis. Morphologic analysis of nerve specimens included light and electron microscopy studies and teased fiber preparation. Survival was evaluated, and the prognostic values of clinical, biologic, and pathologic features were assessed by Cox proportional hazards model. A prognostic assessment based on the significant variables was devised to estimate the probability of survival of any individual patient. RESULTS: Epi- and/or perineurial vasculitis was observed with the same frequency in the 17 patients with sensory and motor deficit and the 15 patients with sensory neuropathies and was associated with axonal degeneration of an average of 77.7% of the nerve fibers. The mean followup was 7.2 years, and the overall survival rate at 5 years was 57%. A full prolonged remission of the vasculitis was observed in 53% of the patients; relapse occurred in 25%. The factors correlated with mortality, in decreasing order of significance, were clinical cutaneous vasculitis (P = 0.0003), neuropathy affecting 3 or 4 limbs (P = 0.03), and depressed level of C4 (P < 0.05). The prognostic assessment indicated a wide range of 5-year probabilities of survival, from < 1% to 93%. CONCLUSION: Necrotizing vasculitis is responsible for the different patterns of noncompressive neuropathies in RA, including mononeuritis multiplex and distal symmetric sensory or sensorimotor neuropathy. Cutaneous vasculitis, multifocal neuropathy, and depressed C4 level were the 3 independent variables which best predicted mortality. We propose a prognostic assessment according to these variables, to stratify patients to receive more aggressive or less aggressive therapy.

Adult↗
PubMed1995

Haplotype analysis of French, British and other European patients with familial amyloid polyneuropathy (met 30 and tyr 77).

Familial amyloid polyneuropathy (FAP) is an autosomal dominant disorder originally and most frequently described in Portugal. The usual constituent amyloid fibril protein is transthyretin (TTR) and the most frequent mutation in the TTR gene associated with FAP (including all Portuguese cases) is that at position 30 (met 30). Three different TTR haplotypes have been described in association with the met 30 mutation in European patients. We studied the haplotypes of 27 families (24 French, 2 British and 1 Greek) with FAP met 30 by analysing three polymorphisms in introns of the TTR gene. We also studied 6 families (2 British, 3 French and 1 Spanish) with FAP tyr 77. There were two main haplotypes in French patients with FAP met 30, one most commonly seen in the French families of Portuguese descent which was the same haplotype as previously described in Portuguese patients (haplotype I) and another haplotype (III) detected in most informative French families not of Portuguese origin. The age of onset of symptoms was consistently later in French than in Portuguese patients and in patients with haplotype III as the disease-associated haplotype rather than haplotype I. British and French patients with the tyr 77 mutation had different haplotypes. The most likely explanation of these findings is multiple founders of both mutations.

Amyloid Neuropathies↗
PubMed1995

A clinical and genetic study of familial cases of Parkinson's disease.

We assessed a group of patients with a family history of Parkinson's disease (PD) in order to see if they differed clinically from sporadic cases and to study their genetic characteristics. Index cases were selected on the basis of clinically typical PD, and at least one affected relative. Fourteen families including 110 first degree and 40 second degree relatives were ascertained. A total of 31 individuals (17 females and 14 males) were found to be affected. This group was compared for selected clinical parameters to 31 age matched patients with sporadic PD. No statistical difference was found between the two groups. In familial cases, both the clinical parameters studied and the course of the disease varied within and between families, as observed in sporadic cases. The genetic transmission was compatible with an autosomal dominant model. The total segregation ratio of 0.25 suggested an incomplete penetrance, which increased with age, from 0 below the age of 30 to 0.43 over the age of 70. Age at onset was earlier in children than in their parents in the 8 multigeneration kindreds studied (mean difference 26 +/- 4.6 years, p = 0.01), whereas it was identical within a generation (mean difference 4.7 +/- 5.7 years, p = 0.1). Although we cannot exclude an ascertainment bias, our results are compatible with an anticipation phenomenon, which deserves further studies for confirmation.

Adult↗
PubMed1995

Transthyretin gene analysis in European patients with suspected familial amyloid polyneuropathy.

We investigated 99 patients from 64 European families (51 French, 11 British, one Italian and one Spanish) with suspected familial amyloid polyneuropathy (FAP) for transthyretin (TTR) gene mutations. Thirty-nine families were found to have point mutations causing the following amino acid substitutions: Met30 (28 families), Tyr77 (five), Arg 50 (one), Ala49 (one), Gln89 (one), Ala60 (one) and one each with previously undescribed mutations at Asn35 and Gys54. The clinical picture in the patients with new and known mutations were typical of FAP, without any specific features for a particular mutation. Onset of symptoms was late (over 50 years) in many French and British patients with the Met30 and Tyr77 mutations, and only 30% of all index cases had affected relatives. We propose an approach to molecular diagnosis in European patients with FAP, apart from members of families with known mutations, based on the frequency of TTR mutations observed in this and and other studies of FAP in Europe. It is logical to screen for the Met30 and Tyr77 mutations and Ala60 in the UK, using restriction enzyme analysis. If these are absent, the TTR gene should be sequenced directly to detect less common or unknown mutations.

Adult↗
PubMed1995

Multifocal motor neuropathy with conduction block: a study of 24 patients.

Twenty four patients with pure motor neuropathy are reported. The chronic motor involvement associated with fasciculations and cramps, mainly in the arms, led, in most patients, to an initial diagnosis of motor neuron disease. In some patients (nine of 24), there was no appreciable muscle atrophy. Tendon reflexes were often absent or weak. The finding of persistent multifocal conduction block confined to motor nerve fibres raises questions about the nature and the importance of this syndrome. Segmental reduction of motor conduction velocity occurred at the site of the block, but significant slowing of motor nerve conduction was not found outside this site. The response to intravenous IVIg treatment seems to be correlated with the absence of amyotrophy. Patients with little or no amyotrophy had an initial and sustained response to IVIg, and did not develop amyotrophy during the follow up study. They could be considered to have a variant of chronic inflammatory demyelinating polyneuropathy. Patients with pronounced amyotrophy independent of the disease duration did not respond as well to IVIg treatment, suggesting the existence of a distinct entity. Among the patients treated about two thirds who had an initial good response to IVIg had high or significant antiganglioside GM1 (anti-GM1) antibody titres, but there was no correlation between the high titres before treatment and long lasting response to IVIg treatment.

Adult↗
PubMed1995

Vasculitic neuropathy.

Vasculitis is a common and treatable cause of neuropathy. In most cases, necrotizing arteritis of the type observed in polyarteritis nodosa is responsible for the lesions, but classification of vasculitis is still uncertain. The neuropathy often occurs in the context of a multisystem disorder, but in a substantial proportion of patients, especially among patients seen by neurologists, the neuropathy is the first and only manifestation of vasculitis. In such cases, the diagnosis can only be reached by performance of a nerve and muscle biopsy. Ischaemic nerve lesions can also result from secondary vasculitis in a number of inflammatory, infectious and immune-mediated disorders of the peripheral nervous system.

Adrenal Cortex Hormones↗
PubMed1994

Nerve biopsy findings in different patterns of proximal diabetic neuropathy.

Besides distal symmetrical sensory polyneuropathy (DSSP), middle-aged diabetic patients may present with focal or multifocal neuropathies, including proximal neuropathy of the lower limbs, the pathophysiological features of which are uncertain. We studied 10 non-insulin-dependent diabetic patients, 45 to 72 years of age, who developed a painful proximal neuropathy of the lower limbs for which other causes of neuropathy were carefully excluded. The proximal neuropathy was asymmetrical in all patients, sensory in 4, motor and sensory in the others. Signs of DSSP were present in all. A sample of the intermediate cutaneous nerve of the thigh, a sensory branch of the femoral nerve, was taken by biopsy and examined by light and electron microscopy. Examination of the nerve specimens revealed ischemic nerve lesions in 3 patients. Nerve ischemia was associated with vasculitis and inflammatory infiltration in 2 of them. In the other patients the lesions of the cutaneous nerve of the thigh included a varying incidence of axonal and demyelinative lesions similar to those observed in DSSP, with mild inflammatory infiltration in 4 of them. The density of myelinated and of unmyelinated was variably decreased. This study shows that axonal and demyelinative lesions similar to those found in diabetic DSSP are present in proximal nerves in mild forms of proximal diabetic neuropathy; while nerve ischemia, inflammatory infiltration, and vasculitis are encountered in the most severe forms of proximal diabetic neuropathy.

Aged↗
PubMed1994

Diarrhea and autonomic dysfunction in a patient with hexosaminidase B deficiency (Sandhoff disease).

The causal factors and the physiopathology of motor diarrhea are still unclear. This case report describes a 60-year-old white man with severe diarrhea for more than 10 years and minor signs of autonomic dysfunction. Extensive investigation showed that small intestinal motility and absorption were normal but that accelerated colon transit precluded water and solute absorption from the large bowel. Orthostatic hypotension, sexual dysfunction, and loss of sweating suggested dysfunction of the autonomous nervous system, which was confirmed by reduced plasma concentrations of norepinephrine and dopamine. Rectal biopsy specimens showed enlarged enteric ganglion cells filled with lipidic material. Levels of total hexosaminidase and hexosaminidase B in plasma, white blood cells, and fibroblasts were decreased, as found in Sandhoff disease. The pedigree of the proband's family showed several affected and heterozygous individuals, detected by examination of total hexosaminidase and hexosaminidase B levels in plasma. Among the five homozygous subjects, three had a clinical picture of diarrhea and orthostatic hypotension since the age of 50. Therefore, hexosaminidase B deficiency should probably be regarded as a cause for dysautonomia; dysfunction of the gastrointestinal tract, manifested by motor diarrhea or esophageal dysmotility, could be the initial and prevalent presentation of dysautonomia.

Autonomic Nervous System Diseases↗
PubMed1994

Infective neuropathies.

Infective neuropathies encompass neuropathies that are among the most common in the world. Retroviral infection, which includes infection with the human immunodeficiency virus, has now spread worldwide. This virus is responsible for a number of disabling peripheral neuropathies, either from the immune reaction that follows penetration of the virus into nervous system of the host, or by opportunistic infection secondary to the major cellular immunodeficit induced by gradual destruction of lymphocytes bearing the CD4 antigen on their surface. In the other class of retroviruses, human T lymphotrophic viruses (HTLV), which are responsible for the HTLV-I-associated myelopathy or tropical spastic paraparesis, peripheral nerve involvement and inflammatory myopathy are less common and milder than in HIV infection. Leprosy continues to pose problems concerning the understanding of the immune mechanisms that lead to the various patterns of nerve lesions encountered in this condition. Chagas' disease, which is due to infection with Trypanosoma cruzi, affects more than 15 million people in Latin America. It is accompanied by mostly subclinical peripheral nerve involvement and by cardiac manifestations from lesions of the autonomic nervous system and cardiac muscle.

AIDS-Related Opportunistic Infections↗
PubMed1993

Experimental carcinomatous plexopathy.

To understand the pathophysiology of carcinomatous plexopathy better, we studied nerve lesions induced by an experimental thyroid carcinoma implanted over the brachial plexus in 30 Fisher rats. We performed a morphological study including light and electron microscopic examination and teased fibre preparations of brachial plexuses from implanted and control animals. The control side was normal in all. A large tumour always grew within 2 months in all implanted animals and a third of the rats eventually developed weakness of the corresponding anterior limb extremity. On gross examination the tumour always surrounded the brachial plexus, which showed a variety of microscopic abnormalities, ranging from isolated endoneurial oedema to total degeneration of nerve fibres in 41% of the implanted rats. The most frequent lesions consisted of segmental demyelination associated with endoneurial oedema at the site of compression. Some axons degenerated distally and regeneration by sprouting of the proximal stump was noted 80 days after implantation. All subpopulations of nerve fibres were equally affected. Invasion of the intrafascicular area by the tumour was an uncommon finding, in comparison with the constant entrapment of the branches of the plexus by the tumour. This invasion by the tumour induced demyelination of nerve fibres at the site of compression, and sometimes at a distance from the tumour. Regeneration did not occur when the tumour had invaded the intrafascicular area.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗