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T Kuntzer

Publications and source records attributed to T Kuntzer.

At least 37 records · Page 2Linked to original sources
PubMed2002

[Neurological manifestations of IgM dysglobulinemia].

Disturbancies in neurological functions associated with paraproteinaemic states are well documented. In recent years increasing attention has been given to paraproteinemia in the absence of evidence of malignancy. In this article we review the main clinical and pathological features associated with IgM paraproteins. Neurological complications affecting the central nervous system are rare, while peripheral neuropathies are frequently observed. Recent advances at the histological and molecular level have allowed a better characterization of clinical syndromes and have given new insights into their pathogenesis. The most convincing evidence for a causal relationship can be drawn from IgM monoclonal gammopathies with specificities directed against carbohydrate determinants of the myelin associated glycoprotein (MAG). There remain, however, many unresolved questions such as how monoclonal anti-MAG IgM antibodies cross the blood-nerve barrier and trigger a chronic demyelinating polyneuropathy while the central nervous system is essentially spared. Current immune therapies for neuropathy associated with IgM paraproteins are temporarily effective in half of patients and are often associated with considerable side effects which limit their prolonged use and efficacy. The availability of safer therapies such as humanized monoclonal antibodies that eliminate specifically B-cell and B-cell precursors may open a new avenue for the management of these patients.

Aged↗
PubMed2002

[Chronic progressive myeloradiculopathy in a 61-year-old man].

A painful worsening of known difficulties in walking led us to investigate a man who presented a spastic paraparesis. Radiological investigations had to be repeated three times before making a diagnosis of a right C6 spinal dural arteriovenous fistula after a 22-month follow-up. Knowing the mechanisms leading to spinal venous hypertension may explain the low yield of the early radiological investigations that should be repeated. The efficiency of the treatment depends on the severity of the presurgical neurologic manifestations.

Central Nervous System Vascular Malformations↗
PubMed2001

[Carpal tunnel syndrome with an unusual cause: a malignant nerve sheath tumor of the median nerve].

We report on the follow-up of a patient who developed symptoms suggestive of carpal tunnel syndrome. Symptoms were however atypical with involvement of the nondominant hand and with selective, fascicular, electroneurographic changes. During the surgical decompression of the median nerve at the wrist a tumor was found, corresponding to an isolated malignant peripheral nerve sheath tumor (MPNST) of mild type. A course of local radiation therapy was completed, with no sign of recurrence, and a normalization of the serum level of neurone specific enolase.

Carpal Tunnel Syndrome↗
PubMed2000

Differential effect of thyroid hormone deficiency on the growth of calretinin-expressing neurons in rat spinal cord and dorsal root ganglia.

The development of spinal cord or dorsal root ganglia neurons expressing calretinin (CR) was studied in thyroid hormone-deficient rats. Immunocytochemical and morphometric analyses showed that the hypothyroidism induced a significant decrease in the number and size of immunoreactive neurons in the spinal cord, as well as stunted growth and arborization of the axons and dendrites. These alterations were observed at different embryonic ages and persisted during the whole postnatal life. In adult hypothyroid rats, the mean number of CR-positive neurons per spinal cord section (31.2 +/- 2.3 in laminae I and II and 30.5 +/- 5.5 in laminae III-X) was significantly decreased (P < 0.001 and P = 0.024, respectively) compared with adult normal rats (68.7 +/- 8.9 and 50.0 +/- 11.0, respectively). In the peripheral nervous system, hypothyroidism altered the growth of sensory neurons expressing CR protein mainly during embryonic life. In comparison with normal rats, hypothyroid embryonic animals showed not only reduced cell size but also a significantly decreased percentage of CR-positive neurons (6.6 +/- 0. 9% in normal, 2.1 +/- 0.3% in hypothyroid rats, P < 0.001). In contrast, although the size of neurons was reduced in hypothyroid young and adult rats, there was no reduction in the percentage of CR-positive neurons. These results showed that thyroid hormone deficiency altered differentially the development of neurons expressing CR protein in the central and peripheral nervous systems. This suggests that central and peripheral neurons are heterogeneous in their sensitivity to thyroid hormone.

Animals↗
PubMed2000

Exercise test in muscle channelopathies and other muscle disorders.

We studied the percentage change in compound muscle action potential (CMAP) amplitude and area during and after a 5-min maximal contraction of the muscle. The exercise test (ET) was performed on 64 patients with different muscle disorders and on 46 normal controls. The range of normal ET values was defined as the mean + 2 SD of the control values. The mean sensitivity of the test was 63% in the whole group with ion channel muscle disorders, the highest sensitivity being seen in primary periodic paralysis (81%) and the lowest in chloride channelopathies (17%). In thyrotoxic periodic paralysis, the ET was abnormal in the three of the four patients studied. In patients with myotonic dystrophy, a smaller than normal increase in CMAP amplitude occurred during and after exercise, whereas in proximal myotonic myopathy a normal initial increase in CMAP amplitude was followed by an abnormal decrement. We conclude that the ET can be of use in confirming abnormal muscle membrane excitability in patients with calcium and sodium channelopathies and thyrotoxic periodic paralysis. In chloride channelopathy, the test may also be abnormal, but shows no, or only a small, increase in amplitude or area in the immediate postexercise period. The test may also be abnormal in proximal myotonic myopathy, but is normal in myotonic dystrophy.

Action Potentials↗
PubMed2000

Clinicopathological and molecular biological studies in a patient with neurolymphomatosis.

We describe a patient with a clinical disorder that resembled vasculitic neuropathy in which peripheral nerves were successively affected over several months, but without systemic involvement. An initial muscle biopsy near the involved nerves showed signs of nonspecific inflammation around the muscle and nerve fibers. Immunosuppressive treatment resulted in a dramatic reduction in pain, but relapses of the disease eventually occurred, and the patient died 22 months after onset of the first symptoms. Pathologically, a malignant non-Hodgkin's B-cell lymphoma, restricted to the intra- and extradural peripheral nervous system, was found. The demonstration by Southern blotting of immunoglobulin heavy chain gene rearrangement confirmed the monoclonal nature of the lymphomatous cells. In situ hybridization tests for Epstein-Barr and herpes virus subtypes were negative. Our case underlines i) how difficult diagnosis can be despite extensive investigations, ii) the usefulness of immunosuppressive treatment in the early stage of the disease, iii) the importance of immunostaining and genome analysis for distinguishing between different types of human neurolymphomatosis, and iv) the fact that the initial inflammatory process in the muscle biopsy may be interpreted either as a paraneoplastic effect of the lymphoma or as a viral inflammatory neuromyopathy that triggers the development of the malignant lymphoma.

Aged↗
PubMed2000

Polyneuropathy attributes: a comparison between patients with anti-MAG and anti-sulfatide antibodies.

Thirty-two patients with a peripheral neuropathy and paraproteinemia were tested for IgM antibodies against myelin-associated protein (MAG) and sulfatide by means of enzyme-linked immunosorbent assay. Nine patients (28 %) had increased anti-sulfatide IgM antibodies and showed a chronic, slowly progressive, distally pronounced, and symmetric polyneuropathy with sensory to sensory-motor impairment, ataxia, hyporeflexia, and axonal involvement in electrophysiological studies. Ten patients (31 %) with increased anti-MAG antibodies had a similar, homogeneous polyneuropathy syndrome but presented with demyelinating features. A weak cross-reactivity between anti-MAG and anti-sulfatide antibodies was present in only three patients. In conclusion, although the two neuropathy groups clearly differed in their electrophysiological features, their clinical presentation was rather similar.

Aged↗
PubMed2000

The mutation of Pro789 to Leu reduces the activity of the fast-twitch skeletal muscle sarco(endo)plasmic reticulum Ca2+ ATPase (SERCA1) and is associated with Brody disease.

Brody disease is a rare inherited disorder of fast-twitch skeletal muscle function and is characterized by a lifelong history of exercise-induced impairment of skeletal muscle relaxation, stiffness, and cramps. The autosomal recessive inheritance of mutations in ATP2A1, the gene encoding SERCA1, which is the fast-twitch skeletal muscle sarcoplasmic reticulum Ca2+ ATPase, has been associated with Brody disease in three of six Brody families in which ATP2A1 has been sequenced. In the present analysis of the ATP2A1 gene in four unrelated families with autosomal recessive inheritance of Brody disease, three mutations were found in two families, leading to premature stop codons and truncated SERCA1. In a third family, the homozygous substitution of T for C2366 led to the missense mutation of Pro789 to Leu. The Pro789 to Leu mutant was readily expressed in HEK-293 cells, but it demonstrated an almost complete loss of Ca2+ transport activity because of reduced Ca2+ affinity. In a fourth family, the heterozygous substitution of T for C2455, mutating Arg819 to Cys, was identified. This mutation was also readily expressed in HEK-293 cells and shown to have near normal Ca2+ transport activity, indicating that it is not causal for Brody disease. These results confirm the genetic heterogeneity of Brody disease and emphasize the importance of a functional test for mutant SERCA1; immunostaining of skeletal muscle to detect the loss of SERCA1a protein is not adequate for the diagnosis of ATP2A1-linked Brody disease.

Adolescent↗
PubMed2000

[Scapular pain and supra-scapular neuropathy in sports medicine].

Eight patients with shoulder pain are reported with a history of athletic activities. On examination, performed with a delay of several months, all patients had painful paresis and atrophy of spinati fossa. Electroneuromyography was carried out in all cases and showed a suprascapular nerve axonal loss from the spinati muscles or infraspinatus muscle, signs of denervation-reinnervation in spinati or infraspinatus muscles, normal examination of other scapular girdle muscles, and a coordinate spinati contraction with shoulder displacement excluding rotator cuff tears. All patients had conservative treatment and only two improved. Six patients underwent surgical decompression of the suprascapular nerve; in three, motor function clearly improved, and in three others pain improved. The factors leading to entrapment include stretch mechanisms associated with shoulder movements, leading to suprascapular nerve liability to mechanical lesions. In patients with shoulder pain, the authors recommend an early electrophysiological work-up to recognize an isolated suprascapular neuropathy. The surgical decompression of the nerve should be based on persistent shoulder pain after conservative treatment.

Adolescent↗
PubMed2000

[Epidemiology of adult neuromuscular disorders].

The percentage and cause of neuromuscular (NM) diseases have been analysed during a 15-year period of time. A NM disorder was found in 10,852 patients (or 14.4% of all neurological patients seen in our hospital). Mononeuropathies have been the most common causes, followed by polyneuropathies and radiculopathies, but with a variable percentage during time for the most frequent causes, that were carpal tunnel syndrome and diabetic polyneuropathies. Myopathies, diseases of the neuromuscular junction and anterior horn cell disorders counted for 5% among all NM disorders during the first 10 years (1% of all neurological patients) and for 12% during the last 5 years (2.4% of all neurological patients), this period corresponds to the opening of our outpatient clinic dedicated to NM diseases. Among polyneuropathies, the most common causes were diabetes mellitus, chronic inflammatory demyelinating polyneuropathies and the inherited forms of peripheral neuropathies. Among myopathies, the most frequently reported symptom was exercise-induced myalgia. The 2 most common muscular dystrophies (MD) were Steinert myotonic MD, and facio-scapulo-humeral MD. Other myopathies were rare, but of diverse causes, all of them corresponding to the newly introduced definition of Rare or Orphan Diseases.

Adult↗
PubMed2000

[Correlation of diseases and disabilities and allocation and modes of transport among the members of an association of patients with neuromuscular diseases. For the Association Suisse Romande contre la Myopathie].

Seventy-nine patients with various chronic neuromuscular disorders returned a questionnaire. We analyzed the linkage between demographic and socio-economic data, type of disease and disability, and types of transportation used. This study shows that whatever type of disability, all patients attach a significant priority to the use of their private vehicle, and that (i) there is a significant correlation between severity of disability and use of disabled people transportation system but not with revenue nor with type of professional activity, and (ii) satisfaction rate is inversely proportional to severity of disability. The relationship between disability and disabled people transportation system appears as logical, but those between revenue and type of transportation is rather complex (role of family, of special refunds from insurance industry, possibility of special loans from the patient organization). The absence of correlation between severity of disability and professional activity must be explained by our choice concerning the scale of disability, which appears too simplistic according to the complexity of the different neuromuscular disorders. It is concluded that (i) co-operation and consultation are needed to give patients better access to disabled people transportation system and to improve technical aids to drive private vehicle and (ii) a more appropriated scale to quantitate disability in neuromuscular disorder patients is needed.

Adolescent↗
PubMed1999

Genetic, cytogenetic and physical refinement of the autosomal recessive CMT linked to 5q31-q33: exclusion of candidate genes including EGR1.

Charcot-Marie-Tooth disease is an heterogeneous group of inherited peripheral motor and sensory neuropathies with several modes of inheritance: autosomal dominant, X-linked and autosomal recessive. By homozygosity mapping, we have identified, in the 5q23-q33 region, a third locus responsible for an autosomal recessive form of demyelinating CMT. Haplotype reconstruction and determination of the minimal region of homozygosity restricted the candidate region to a 4 cM interval. A physical map of the candidate region was established by screening YACs for microsatellites used for genetic analysis. Combined genetic, cytogenetic and physical mapping restricted the locus to a less than 2 Mb interval on chromosome 5q32. Seventeen consanguineous families with demyelinating ARCMT of various origins were screened for linkage to 5q31-q33. Three of these seventeen families are probably linked to this locus, indicating that the 5q locus accounts for about 20% of demyelinating ARCMT. Several candidate genes in the region were excluded by their position on the contig and/or by sequence analysis. The most obvious candidate gene, EGR1, expressed specifically in Schwann cells, mapped outside of the candidate region and no base changes were detected in two families by sequencing of the entire coding sequence.

Base Sequence↗
PubMed1999

[Facial myositis: a localized form of generalized myositis?].

We report a case of myositis presenting as an apparently unique progressive facial weakness. The only biological abnormality after an 8-year follow-up was an immunocytoma. Molecular analyses excluded facioscapulohumeral muscular dystrophy. Based on this single case and a review of the literature, we suggest a continuum between focal myositis and generalized myositis.

Diagnosis, Differential↗