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W Mortier

Publications and source records attributed to W Mortier.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Regional distribution of predisposition to maligant hyperthermia in Germany: tate in 1997].

Malignant hyperthermia (MH) is a rare autosomally dominantly hereditary and potentially life-threatening disease. The prevalence of the genetic MH predisposition is estimated as 1:10,000 to 1:20,000. In Germany no data on the regional distribution are available. Therefore, the purpose of this investigation is to summarise and present the epidemiological data of all German MH laboratories. Nine German hospitals offer the specific in vitro contracture test to diagnose the MH predisposition. All German MH laboratories carry out the examination in accordance with the standardised protocol of the European Malignant Hyperthermia Group. The laboratories were asked to provide the number of all patients investigated, excluding those suffering from other neuromuscular diseases, separated according to diagnostic groups and their places of residence, the number of the identified MH-families as well as the number of the clinically suspected and investigated MH cases with their places of residence. Eight MH laboratories provided the requested data. Until September 1997 a total of 2620 patients were investigated. In 865 patients (34%) MH suspicion was confirmed (diagnosis: MHS). 1494 patients (56%) were released by investigation from MH-suspicion (diagnosis: MHN). In 261 patients (10%) the MH-predisposition remained unsolved (diagnosis: MHE). 580 MH families were identified. Among 2620 patients 757 were clinically suspected MH cases. 35% of these suspected MH cases were classified as MHS, 10% as MHE and 55% as MHN. The documentation of the patients places of residence classified as MHS and MHE into a map of Germany demonstrates an exhaustive distribution with an increased regional prevalence in the areas of the MH laboratories. This concentration in the area of the MH laboratories becomes even more evident, when the places of residence of the MH suspected cases are demonstrated. In conclusion, the distribution of the MH predisposition is uniform and exhaustive in Germany. The presented regional concentration of clinically suspected MH cases among the MH laboratories is mainly interpreted as an expression of effective regional education and information. Considering the overall incidence of the MH predisposition as described above only 15-20% of the MH patients have so far been identified. The MH laboratories have already released about 10,000 patients from the suspicion of MH predisposition. A preliminary prevalence of at least 1:60,000 to 1:80,000 in Germany can be estimated according to the presented data.

Epidemiologic Studies↗
PubMed1997

Congenital myasthenic syndromes: clinical and genetic analysis of 18 patients.

Congenital myasthenic syndromes (CMS) are a group of rare gentic disorders in which neuromuscular transmission is compromised by a variety of mechanisms, other than autoimmunity. Recently, substantial progress has been made by the identification of mutations in acetylcholine receptor (AChR) genes which cause CMS. We report on the clinical and genetic analysis of 18 independent CMS patients. All patients were clinically classified as sporadic cases of CMS (group III according to ENMC consensus). In order to investigate the prevalence of AChR mutations in this group we analyzed structural domains of the AChR genes at strategically important sites - the channel pore-lining regions (M2 domains) of the alpha, beta and epsilon subunits, and the extracellular domain close the acetylcholine (ACh) binding site. All patients showed wild-type sequence in these regions, mutations were not detected. Therefore, we conclude, that point mutations in domains which are known to cause slow channel congenital myasthenic syndromes (SCCMS) are rare in group III-patients in Germany. Determining the genetic defects causing CMS may have implications for diagnosis and genetic counseling of CMS patients. Moreover, this may be important for the therapeutic management of CMS as some patients may profit form quinidine sulfate. Therefore, further efforts will be undertaken to elucidate the underlying defects of CMS.

Adolescent↗
PubMed1997

In vitro contracture test for diagnosis of malignant hyperthermia following the protocol of the European MH Group: results of testing patients surviving fulminant MH and unrelated low-risk subjects. The European Malignant Hyperthermia Group.

BACKGROUND: Determination of sensitivity and specificity of the in vitro contracture test (IVCT) for malignant hyperthermia (MH) susceptibility using the European MH Group (EMHG) protocol has been performed in some laboratories but only on a small sample from the combined EMHG. Thus, the purpose of the present study was to determine combined EMHG sensitivity and specificity of the test. METHODS: Results of IVCT of patients with previous fulminant MH and normal, low-risk subjects (controls) were collected from 22 centres of the EMHG. IVCT was performed according to the EMHG protocol. Patients were included in the study if the clinical crisis had a score of at least 50 points with the Clinical Grading Scale. Low-risk subjects were included provided they did not belong to a family with known MH susceptibility, they had not developed any signs of MH at previous anaesthetics, and they did not suffer from any neuromuscular disease. For inclusion of both MH patients and low-risk subjects, at least 1 muscle bundle in the IVCT should have twitches of 10 mN (1 g) or more. For evaluation of individual tests, only muscle bundles with twitch heights of 10 mN (1 g) or more were used. RESULTS: A total of 1502 probands had undergone IVCT because of a previous anaesthesia with symptoms and signs suggestive of MH. Of these, 119 had clinical scores of 50 and above. From these 119 MH-suspected patients and from 202 low-risk subjects, IVCT data were collected. Subsequently, 14 MH-suspected patients were excluded from further analysis for the following reasons: In 3 patients, the suspected MH episode could be fully explained by diseases other than MH; in 11 MHS patients, IVCT was incomplete (n = 1), data were lost (n = 3), or none of the muscle bundles fulfilled twitch criteria (n = 7). Of the remaining 105 MH-suspected patients, 89 were MHS, 10 MHEh, 5 MHEc, and one MHN. Thus, we observed a diagnostic sensitivity of the IVCT of 99.0% if the MHE group is considered susceptible (95% confidence interval 94.8-100.0%). Of the 202 low-risk subjects, 3 were MHS, 5 MHEh, 5 MHEc, and 189 MHN. This gives a specificity of the IVCT of 93.6% (95% confidence interval 89.2-96.5%). CONCLUSION: The IVCT for diagnosis of MH susceptibility in Europe has a high sensitivity and a satisfactory specificity.

Adolescent↗
PubMed1993

Subtotal aplasia of myelinated nerve fibers in the sural nerve.

Thus far, only very few cases with neuronal maldevelopment in the peripheral nervous system have been reported (Table 1). The present sporadic case manifested itself with peripheral sensorimotor polyneuropathy in early infancy. Clinical findings included pareses and hypaesthesia of distal extremities and severely reduced nerve conduction velocities. During adolescence, cerebellar ataxia developed. Sural nerve biopsy taken at the age of 14.5 years showed severe fascicular hypoplasia, aplasia of large myelinated nerve fibers, and subtotal deficiency of small myelinated nerve fibers without numerical reduction of unmyelinated axons. There was no structural evidence of a progression of myelinated fiber breakdown although some collagen pockets and empty Schwann cell processes among preserved unmyelinated axons indicated some loss of unmyelinated fibers. These findings are interpreted as representing maldevelopment of the myelinated fibers in the peripheral nervous system. Appropriate classification of this unique disease among the known developmental disorders of peripheral nerves is discussed.

Adolescent↗
PubMed1993

[Diagnosis of malignant hyperthermia susceptibility. 1. The significance of in vitro susceptibility tests].

UNLABELLED: Molecular genetic findings indicate genetic heterogeneity in susceptibility to malignant hyperthermia (MH). At present the in vitro contracture test (IVCT) is still the most reliable diagnostic procedure for MH susceptibility. It must be performed in a standardized fashion. METHODS. We investigated 350 patients (233 children and 117 adults) using the protocol of the European MH Group for the IVCT. The test results were classified as susceptible to MH (MHS), non-susceptible to MH (MHS), non-susceptible to MH (MHN) and equivocal (MHE), with an abnormal caffeine result designated MHEc and an abnormal halothane result designated MHEh. Reasons for the IVCT were a positive family history for MH susceptibility (n = 94), a MH reaction (n = 157), creatine kinase elevation unknown aetiology (n = 53) and different neuromuscular diseases (NMD, n = 46). Physical, neurological and laboratory work-up included serum enzymes, nerve conduction studies, electromyography and muscle biopsy evaluated by different techniques. Thirty-one children and 11 adults were MHS, while 152 children and 80 adults were MHN. MHE findings were obtained in 50 children and 26 adults. While the MHS and MHN groups are diagnostically safe, the equivocal group is not, with possible false-negative or false-positive interpretation. The high number of MHE findings most probably is explained by the high proportion of patients with NMD (53% of the children, 69% of the adults). RESULTS. In a group of 18 boys with Duchenne or Becker muscular dystrophy, ranging in age from 1.5 to 24 years, the IVCT results were twice MHS, once MHE, and MHN in the remaining 15 cases. In seven other boys with Duchenne or Becker muscular dystrophy, proven by molecular techniques, there were anaesthetic complications with MH-like symptoms. After administration of trigger substances, five out of the seven suffered a cardiac arrest, two of whom died. In the surviving five boys the IVCT results were three times MHN, once MHE and once MHS. Most probably these boys suffered from effects of succinylcholine, possibly potentiated by other trigger substances. The adverse cardiac reactions are attributed to triggered rhabdomyolysis with associated hyperkalemia but not a primary hereditary disposition to MH. CONCLUSION: In patients with NMD, MHS and MHE test results do not indicate a hereditary, heterogeneous disposition to MH; the majority will be caused by a secondary induced disturbance of calcium homoeostasis in the diseased muscle cells. These results do, however, indicate the following: (1) Patients with NMD exposed to trigger substances are at higher risk than the general population for MH-like episodes, including sudden death. (2) NMD therefore should be diagnosed as early as possible and patients should not be exposed to trigger substances when alternatives are at hand. (3) Diagnostic procedures in patients having suffered an MH-like episode should include IVCT and special investigations to exclude or substantiate other NMD. The work-up may be changed if a family member is properly classified as MH susceptible. (4) In patients with known NMD there is no indication for performing IVCT, since the results may even be misleading.

Adult↗
PubMed1993

[Diagnosis of malignant hyperthermia susceptibility. 2. Anesthesia for muscle biopsy. Differential diagnosis in negative test results].

At present the in vitro caffeine-halothane contracture test is the only test to predict susceptibility to malignant hyperthermia (MH) with acceptable sensitivity and specificity. Anaesthesia is necessary for the excision of muscle bundles from the vastus lateralis muscle. MATERIAL AND METHODS. Between 1983 and 1991, muscle biopsies were taken from 350 patients, 233 children and 117 adults. In 197 cases, trigger-free general anaesthetics were supplemented by ventilation, via mask in 124 cases and via tracheal intubation in 73 cases. One hundred and fifty-three muscle biopsies were performed under regional or local anaesthesia with or without sedation. Fourteen of the patients with regional anaesthesia needed an additional general anaesthetic to tolerate the operation. For premedication midazolam was administered orally. The general anaesthetics consisted of etomidate or propofol with fentanyl or alfentanil, always with nitrous oxide and oxygen. For local anaesthesia we used procaine or prilocaine. During the first 3 years local infiltration of the thigh was used, but subsequently direct nerve blockade of the femoral nerve and the lateral cutaneous femoral nerve was preferred. RESULTS. In all cases of general anaesthesia and in 91.6% of cases of regional anaesthesia operating conditions were very good. Fourteen (8.4%) of the patients with regional anaesthesia needed an additional general anaesthetic. There were no severe complications noticed. Moderate complications were found in 29 of the 194 paediatric general anaesthesias (15%) and in 5 of the 117 regional anaesthesias in adults (4%); all were easy to treat. The 50 paediatric regional anaesthesias and the three general anaesthesias in adults were without complications. DISCUSSION. For muscle biopsies, trigger-free general anaesthesia can be recommended as well as peripheral nerve blockades. Complete monitoring is necessary, even for this minor procedure: ECG, blood pressure, pulse oximetry, capnometry, measurement of body temperature and blood gas status. Differential diagnosis in negative test results. In patients who suffer an anaesthetic incident, the following disease must be considered: myopathies (especially the congenital myopathies and muscular dystrophies), respiratory problems due to pulmonary infection and obstruction, metabolic disorders of various origins, and the problem of masseter spasm.

Adolescent↗
PubMed1993

[Anesthesia and intensive therapy for a patient with mitochondrial myopathy].

Since 1983 we have been involved in the diagnostic work-up and emergency treatment of a female patient now 48 years old who has a mitochondrial myopathy resembling Luft's disease. The syndrome was first described in 1959, and in more detail in 1962, by Luft and et al., who reported a picture of hypermetabolism with high temperature, extreme sweating, tachycardia, dyspnoea at rest, polydipsia, polyphagia and irritability but normal thyroid function. In 1971 and 1976 Haydar and Di Mauro presented a second case and proposed treatment with chloramphenicol. Our patient has the third case of the syndrome reported so far: her case was initially published in 1987. CASE REPORT. Since her 17th year of life the patient had suffered from episodes of fever, tachycardia and sweating. At the age of 32 these attacks worsened, leading to unconsciousness and apnoea. The patient then had to be intubated, ventilated and sometimes resuscitated. The diagnosis of MH susceptibility and Luft's disease was made on biochemical grounds after the first muscle biopsy in 1983. Therapy with chloramphenicol failed. Therapy with beta blockers, vitamin C and K or E, coenzyme Q10 and a high-caloric diet was started in 1985. The patient was registered with an emergency service, which flew her to our ICU whenever she had a severe crisis. For milder episodes she was supplied with an oxygen breathing mask at home. Myalgia increased with the episodes starting in 1988, and the patient needed dantrolene infusions and analgesics at home. To facilitate venepuncture a Port-A-Cath system was implanted in 1987, which had to be removed four times due to infection and sepsis. A muscle biopsy was taken in Rotterdam, which revealed differences in mitochondrial function from the biochemical findings recorded in 1983 and not in keeping with Luft's disease. Unfortunately, the patient was not able to undergo further metabolic investigations or therapeutic trials. ANAESTHESIA. The patient received three local and six general anaesthetics in our clinic. The muscle biopsies, two in 1983 and one in 1985, were performed under local infiltration with procaine and were uneventful. The general anaesthetics were carried out without MH trigger substances following pretreatment with dantrolene for the following surgical procedures: the repair of an extensive arterio-venous fistula between the brachiocephalicus trunk and the right jugular and subclavian vein, revision of the sternum cerclage, implantations and explanations of infectious Port-A-Cath systems. We used etomidate, propofol and fentanyl or alfentanil with nitrous oxide and oxygen for induction and maintenance of anaesthesia. Muscle relaxation was induced with vecuronium or atracurium. All cardiovascular, respiratory, metabolic and temperature measurements stayed in normal ranges. After the extensive vascular repair (av fistula) the patient had to be mechanically ventilated for some hours until normal body temperature was restored. At the end of all other periods of anaesthesia she was extubated in the operating theatre. In five cases the postoperative period was uneventful. Only once she developed a crisis with hyperthermia, tachycardia, sweating and dyspnoea. INTENSIVE CARE. From 1985 to 1992 the patient was treated in our ICU 21 times. On 11 occasions she was already intubated and being ventilated by the emergency service on arrival. Extubation was usually possible within 2-20 h. During the crisis, heart rate was about 160-190 per minute and temperature above 40 degrees C. Serum values of CK, glucose, BUN, electrolytes, lactate and thyroid hormones were always in the normal ranges. Blood gas controls showed a constant respiratory alkalosis, arterial pCO2 values decreasing to 20 mm Hg or less. In addition to mechanical ventilation, treatment consisted in dantrolene infusions and droperidol injections, supplemented from 1989 onward with piritramide injections because of the increased severity of myalgia. In 1991 we gave propofol by

Anesthesia↗
PubMed1990

Anesthesia in neuromuscular diseases.

Neuromuscular diseases raise a lot of anesthesia related problems. The first is the hitherto unknown disease discovered by an unexpected adverse reaction to anesthetics or/and muscle relaxants up to a life-threatening incident. A second problem is the probable, suspected or proven disposition to malignant hyperthermia in patients with other neuromuscular diseases. Furthermore, severe rhabdomyolysis can be induced in myopathic muscle by the application of succinylcholine alone or in combination with inhalational anesthetics resulting in hyperkalemia, myoglobinuria and CK-elevation, sometimes followed by cardiac arrest. Cardiomyopathy is a common feature in many neuromuscular diseases. All cardiodepressant agents must be avoided. Specific problems with muscle relaxants arise in myasthenia gravis and in the myotonias. In the later stages of severe neuromuscular diseases the main problem concerning anesthesia is respiratory failure. The individual risk of every patient has to be evaluated before anesthesia. Recommendations for the anesthetic management are given.

Anesthesia↗
PubMed1988

Mitochondrial myopathies with necrotizing encephalopathy of the Leigh type.

Two patients with mitochondrial encephalomyopathy (MEP) serve to emphasize the variability of this group of diseases. Cerebral insults, mitochondrial cardiopathy, relapsing ileus, cerebral angioma, ataxia, and myoclonic seizures characterized the first case of an adult man with similar diseases in his family, interpreted as transitional form between mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) and myoclonus epilepsy associated with ragged red fibers (MERRF). The second patient, a floppy infant with cardiomyopathy and myoclonism, statomotoric and mental retardation showed combined defects in mitochondrial respiratory chain at NADH-CoQ reductase and cytochrome c oxidase and a deficiency of carnitine. In both patients neuropathologically criteria of Leigh's syndrome could be demonstrated in the cerebral cortex, in case 2 also clinically. The classificatory problems of the relationships between KSS, MELAS, MERRF, Leigh's as well as Alpers' syndromes are discussed.

Adult↗
PubMed1986

Screening for Duchenne muscular dystrophy: an improved screening test for creatine kinase and its application in an infant screening program.

A kinetic bioluminescence assay with optimized reagent conditions has been developed for application as a screening test for increased creatine kinase (CK) activities in dried blood spots. This test is used for the early detection of Duchenne muscular dystrophy (DMD) in a voluntary CK screening program in West Germany. Of the 176,600 boys tested up to December 31, 1984, 48 who were less than 6 months old had certain or probable DMD (frequency 1: 3679). In 1983 and 1984, the rate of false positive results was 0.016% for a cut-off activity 300 U/liter and 0.061% for a cut-off activity 180 U/liter. Long-term counseling is offered to families of newly detected DMD patients in order to facilitate the aims of the screening program, namely, avoidance of secondary cases in affected families, early professional care for the sick child, and the early opportunity to make the appropriate decisions for a life with an handicapped child. Two types of a benign hereditary blood anomaly were also detected by CK screening (CK-BB inside erythrocytes or thrombocytes).

Age Factors↗
PubMed1984

[Longtime care of spina bifida patients. Therapy and prognosis in the last 20 years].

206 patients with spina bifida were followed up during the last 20 years; they were examined from the pediatric, neurosurgical, urological and orthopedic point of view. Evaluation of the intellectual development was also performed. Most of the 92 children of the first group were born after Lorber in 1971 proposed a selective policy of treatment of newborn infants, 144 (group 2) prior to this time. Shunting devices to alleviate hydrocephalus were necessary in two thirds of all patients. The incidence of shunt obstruction most commonly of the ventricular end was very high during the first two years of age but decreased sharply thereafter. Radiological screening disclosed pathological changes of the upper urinary tract in more than one fourth of all children, especially in girls. In the older group 28% of the patients over 5 years of age were mainly bound to a wheelchair, as opposed to 14% in the younger group. Epileptic seizures occurred in 27 cases. Children with thorakolumbar lesions proved to have a poorer intellectual development than those with lumbosacral lesions. Low IQs (less than 90) were also evaluated in every second patient with a shunt dependent hydrocephalus. Since the adoption of selective treatment the percentage of patients with severe handicap has decreased significantly.

Adolescent↗
PubMed1982

Subacute sclerosing panencephalitis in a brother and sister. Therapeutic trial of fibroblast interferon.

This paper describes the very rare occurrence of subacute sclerosing panencephalitis (SSPE) in two siblings: a Turkish boy and his younger sister. The clinical picture was characteristic, and the diagnosis was confirmed in both cases by appropriate laboratory examination. The interval between the occurrence of the first neurological symptoms in the boy, and subsequently in the girl was four years. Study of HLA- and 27 other polymorphic marker-systems did not reveal linkage to one of the systems tested. Therapeutic trials in the girl included intravenous and intraventricular application of a total of 87 X 10(6) U human fibroblast interferon (Hu INF-beta) over 21 days. However, up to 3 months after the end of interferon administration there were no significant changes in the girl's condition.

Adolescent↗
PubMed1982

Pharmacological in-vitro studies in malignant hyperthermia in childhood.

In 91 children the caffeine-halothane test was performed according to the technique used by Britt et al and Kalow et al. The muscles investigated, 12 mm long and 2 to 3 mm in diameter, showed concentration dependent contractures to caffeine and a distinct potentiation after adding halothane. Compared to adults children above the age of 2 show a higher range for caffeine-induced contractures but infants below this age responded the strongest in range and average. While children with neuromuscular diseases usually revealed contractures less than average compared to the reference group there are special myopathies and muscle conditions which lead to a normal reaction to caffeine but increased ones to caffeine plus halothane. The reason for this remains unknown but the patients concerned should be treated like individuals with the proven trait for MH. Out of 22 patients being possibly MH susceptible [9] or having survived an anaesthetic complication [13] 4 showed decreased caffeine thresholds and increased contractures to caffeine plus halothane which is in accordance with MH susceptibility. Basically the pharmacological in-vitro test may reveal false negative results due to diseased muscle fibres or a shifted sensitivity of the contractile elements to calcium. Practically most important however is the inconvertible diagnosis of MH in a given patient, which in the very end will allow decision on the validity of the pharmacological test being used.

Adolescent↗
PubMed1982

Lymphocyte capping in muscular dystrophies.

Since reports of lymphocyte capping in muscular dystrophies of various authors revealed controversial results, we investigated 47 patients and carriers with Duchenne or Becker-Kiener muscular dystrophy according to different methods. There was no significant reduction of cap formation compared to 64 healthy controls, both groups showing a mean of about 75% caps. Reduced numbers of caps, however, could be demonstrated in three otherwise healthy probands aged 70 years or more, two patients under interferon treatment, four patients under high dose methotrexate therapy as well as one patient with untreated chronic myeloic leukemia. Thus lymphocyte capping in our experience is far from being a valid method for carrier detection or prenatal diagnosis of muscular dystrophies.

Adolescent↗