Longitudinal gut microbiome changes in immune checkpoint blockade-treated advanced melanoma

Multiple clinical trials targeting the gut microbiome are being conducted to optimize treatment outcomes for immune checkpoint blockade (ICB). To improve the success of these interventions, understanding gut microbiome changes during ICB is urgently needed. Here through longitudinal microbiome profiling of 175 patients treated with ICB for advanced melanoma, we show that several microbial species-level genome bins (SGBs) and pathways exhibit distinct patterns from baseline in patients achieving progression-free survival (PFS) of 12 months or longer (PFS ≥12) versus patients with PFS shorter than 12 months (PFS <12). Out of 99 SGBs that could discriminate between these two groups, 20 were differentially abundant only at baseline, while 42 were differentially abundant only after treatment initiation. We identify five and four SGBs that had consistently higher abundances in patients with PFS ≥12 and <12 months, respectively. Constructing a log ratio of these SGBs, we find an association with overall survival. Finally, we find different microbial dynamics in different clinical contexts including the type of ICB regimen, development of immune-related adverse events and concomitant medication use. Insights into the longitudinal dynamics of the gut microbiome in association with host factors and treatment regimens will be critical for guiding rational microbiome-targeted therapies aimed at enhancing ICB efficacy.

A new variable phenotype in spinocerebellar ataxia 27 (SCA 27) caused by a deletion in the FGF14 gene

We present a young boy whose mild ataxia and abnormal eye movements repeatedly deteriorated with fever, making him unable to sit or walk during fever episodes. SNP-array analysis identified a 202 kb deletion in chromosome 13q33.1 containing the fibroblast growth factor (FGF)14 gene, which is associated with spinocerebellar ataxia (SCA) 27. This 13q deletion was also present in the proband's mother and grandmother. The mother was unable to perform tandem gait walking and had abnormal eye movements but had never sought medical attention. The grandmother predominantly had a postural tremor. FGF14 regulates brain sodium channels, especially in the cerebellum. Sodium channels can be fever sensitive. This family demonstrates phenotypic variability of FGF14 deletions (SCA 27), fever sensitivity of ataxia and the added value of SNP-array analysis in making a diagnosis.

[Intracranial hemorrhages in infants: child abuse or a congenital coagulation disorder?]

In children with head injuries the severity of the neurological symptoms should concord with the patient's history and signs of neurotrauma on examination. Discrepancies between the (hetero)anamnesis and physical examination on the one hand and neurological findings on the other may indicate child abuse. The presence of both old and new intracranial haemorrhages in the absence of proportional trauma is generally considered as evidence for child abuse. However, these symptoms may also be the first manifestation of a congenital coagulation disorder. Three children, two girls aged 8 and 5 months and a boy aged 6 months were presented with alarming neurological symptoms due to intracranial haemorrhages without external signs of head trauma. The first girl had 'shaken baby' syndrome while the other 2 had congenital coagulation disorders (haemophilia B and factor V deficiency, respectively). All three recovered, the last two with remaining one-sided neurological deficits. Child abuse and congenital coagulation disorders may present with similar neurological symptoms and radiological findings. In these patients coagulation tests are mandatory and--if abnormal--enable early substitution of deficits and prevent inappropriate suspicion or accusation of caretakers.

[Children with stumbling gait due to acute spinal cord compression]

Three previously healthy children, two girls aged 2 and almost 5 years and a boy aged 20 months, developed a progressively stumbling gait within days. In two this occurred after a period of weeks during which they complained of, or seemed to have back pain. In all three cases acute spinal cord compression by a malignant tumour was diagnosed. Histological examination revealed Ewing sarcoma, granulocytic sarcoma and T-cell lymphoma. Surgical decompression led to complete neurological recovery. Although rare, acute spinal cord compression during childhood is a medical emergency because of the risk of neurological morbidity. Back pain, weakness and a stumbling gait usually are the first symptoms. Sensory symptoms and sphincter dysfunction may develop later. Early recognition is essential, as prognosis depends on neurological findings and duration of symptoms when treatment is started.

Genotype and phenotype in patients with dihydropyrimidine dehydrogenase deficiency

Dihydropyrimidine dehydrogenase (DPD) deficiency is an autosomal recessive disease characterised by thymine-uraciluria in homozygous deficient patients and has been associated with a variable clinical phenotype. In order to understand the genetic and phenotypic basis for DPD deficiency, we have reviewed 17 families presenting 22 patients with complete deficiency of DPD. In this group of patients, 7 different mutations have been identified, including 2 deletions [295-298delTCAT, 1897delC], 1 splice-site mutation [IVS14+1G>A)] and 4 missense mutations (85T>C, 703C>T, 2658G>A, 2983G>T). Analysis of the prevalence of the various mutations among DPD patients has shown that the G-->A point mutation in the invariant splice donor site is by far the most common (52%), whereas the other six mutations are less frequently observed. A large phenotypic variability has been observed, with convulsive disorders, motor retardation and mental retardation being the most abundant manifestations. A clear correlation between the genotype and phenotype has not been established. An altered beta-alanine, uracil and thymine homeostasis might underlie the various clinical abnormalities encountered in patients with DPD deficiency.

Severe irreversible optic neuritis following Mantoux tuberculin skin test in a child with multiple sclerosis--a case report

A 12-year-old girl was diagnosed as suffering from multiple sclerosis. At age 14, just after recovery from an exacerbation of MS with left-sided optic neuritis, she underwent a Mantoux tuberculin skin test. Within 30 minutes she developed complete irreversible optic neuropathy of the left eye. This case illustrates the urge for caution to perform vaccinations and tuberculin skin tests not only during progressive disease activity of MS, but also in the reconvalescent phase after an acute exacerbation.

Cerebral cavernous hemangiomas in childhood. Clinical presentation and therapeutic considerations

Cerebral cavernous hemangiomas (CCH) are relatively rare vascular hamartomas. Since the introduction of MRI there has been an increase in the number of case reports of CCH in the medical literature. CCH are often asymptomatic; they may, however, cause epilepsy or neurological deficits due to their space-occupying effects or hemorrhagic sequelae. The tendency of CCH to bleed has been well recognized, though gross hemorrhage is infrequent owing to the relatively low blood pressure and small blood flow in CCH. MRI findings of a CCH are characteristic and can differentiate the lesions from other vascular abnormalities. To date, there has been no consensus on indications for surgical intervention. Three cases are presented, which together demonstrate by their different presentation, clinical course and MRI findings that each patient with a CCH requires an individually tailored management. Presentation, clinical course and accessibility for operation are the factors that determine whether a surgical or a conservative approach should be adopted.

Magnetic resonance imaging in classification of congenital muscular dystrophies with brain abnormalities

A survey was performed of magnetic resonance imaging (MRI) findings in 21 patients with congenital muscular dystrophy (CMD) with cerebral abnormalities to evaluate the contribution of MRI to the classification of CMD patients. In 5 patients with Walker-Warburg syndrome (WWS), MRI showed hydrocephalus due to aqueduct stenosis, generalized cerebral cortical agyric or pachygyric polymicrogyria, diffuse cerebral hemispheric white matter abnormalities, and malformations of posterior fossa structures. In 4 patients with muscle-eye-brain disease, MRI showed cortical dysplasia, but less severe than in WWS. The cerebral white matter either was normal or contained multiple focal abnormalities. Malformations of posterior fossa structures were present. Eight patients, classified as having classic merosin-deficient CMD (MD-CMD), had diffuse cerebral hemispheric white matter abnormalities, no other abnormalities. One patient with MD-CMD had only a few, focal white matter abnormalities. Three CMD patients had occipital agyria, otherwise normal gyration, multifocal or more diffuse cerebral white matter changes, and variable hypoplasia of pons and vermis. Two of the 3 patients had negative muscle merosin staining. The conclusion of the study is that MRI is an important adjunct in the classification of CMD patients. CMD with occipital agyria can be regarded as a newly recognized, separate CMD subtype.

Congenital supratentorial arachnoidal and giant cysts in children: a clinical study with arguments for a conservative approach

Little is known about the natural course of arachnoidal cysts (AC) and the incidence of complications. This poses a problem in selection of patients for surgical interventions. The present authors report on 19 children with supratentorial AC of varying location and size. The mean follow-up time is 6 years. The evolution of presenting symptoms, the developmental course, the occurrence of complications, the surgical intervention performed and its outcome are described. Associated neurological disorders cannot always be attributed to the cyst. If surgery is being considered, a causal relationship between the symptom and the cyst should be plausible.

Deficiency of the voltage-dependent anion channel: a novel cause of mitochondriopathy

A patient with a deficient voltage-dependent anion channel (VDAC) is reported, presenting clinically with psychomotor retardation and minor dysmorphic features. Biochemical studies on muscle mitochondria showed impaired rates of pyruvate oxidation and ATP production; however, no specific deficient activity of one of the mitochondrial enzymes was involved. Western blotting experiments indicated an almost complete VDAC deficiency in skeletal muscle. The only moderately decreased VDAC content in the patient's fibroblasts might indicate that VDAC is expressed in a tissue-specific manner. The deficiency is likely caused by a mutation in the HVDAC1 gene or by a distributed posttranslational modification. This is the first described deficiency of a component of the outer mitochondrial membrane associated with the pyruvate oxidation pathway. Defects in this membrane should be considered as a possible cause of otherwise unexplained mitochondrial disorders.

A (G-to-A) mutation in the initiation codon of the proteolipid protein gene causing a relatively mild form of Pelizaeus-Merzbacher disease in a Dutch family

Pelizaeus-Merzbacher disease (PMD) is an X-linked recessive disorder that is characterized by dysmyelination of the central nervous system resulting from mutations in the proteolipid protein (PLP) gene. Mutations causing either overexpression or expression of a truncated form of PLP result in oligodendrocyte cell death because of accumulation of PLP in the endoplasmic reticulum. It has therefore been hypothesized that absence of the protein should result in a less severe phenotype. However, until now, only one patient has been described with a complete deletion of the PLP gene. We report a Dutch family with a relatively mild form of PMD, in which the disease cosegregates with a (G-to-A) mutation in the initiation codon of the PLP gene. This mutation should cause the total absence of PLP and is therefore in agreement with the hypothesis that absence of PLP leads to a mild form of PMD.

Leukoencephalopathy with swelling in children and adolescents: MRI patterns and differential diagnosis

In children, several neurological disorders are characterised by spongiform leukoencephalopathy. MRI of the brain typically shows white matter swelling, but does not enable differentiation of the various underlying disorders. The aim of this article is optimisation of the diagnostic value of MRI in leukoencephalopathy accompanied by swelling. MRI-based inclusion criteria were met by 20 patients in our database. The images were analysed using a detailed scoring list. In 13 of the 20 patients the clinical diagnosis was known (11 definite and 2 probable diagnoses). Characteristic MRI abnormalities could be defined in these patients. Of the 7 patients without a diagnosis, 5 had identical MRI abnormalities: diffuse hemisphere swelling and typical cysts in frontoparietal subcortical white matter and the tips of the temporal lobes. The clinical picture was also similar in these patients, suggesting a similar disease.

Molecular basis of phenotypic variation in patients with argininemia

Argininemia is an autosomal recessive disorder caused by a deficiency in the liver-type arginase enzyme. Clinical manifestations include progressive spastic diplegia and mental retardation. While the quality of life can severely deteriorate in most such patients, some do show remarkable improvement in neurological symptoms while on controlled diets. We examined the thesis that differences in clinical responses to dietary treatment are based on molecular heterogeneity in mutant arginase alleles. Genomic DNAs from 11 patients with argininemia were examined using the polymerase chain reaction, cloning, and sequencing. Nine mutations representing 21/22 mutant alleles were identified in 11 patients with argininemia, and four of these mutations were expressed in vitro to determine the severity of enzymatic defects. We found that these mutations accounted for 64% of the mutant alleles in our patients. Based on findings in vitro expression tests, the mutations can be considered either severe or moderate. Patients with at least one moderate mutant allele responded well to dietary treatment; concentrations of plasma arginine were controlled within 300 microM. In contrast, patients with two severely mutated alleles did not respond to dietary treatment and plasma arginine was over 400 microM. Argininemia is heterogeneous at the molecular level. The degree of clinical improvement during dietary treatment is reflected in the concentration of arginine in plasma, as a measure of metabolic control. Plasma arginine levels during treatment is reflected in the concentration of arginine in plasma, as a measure of metabolic control. Plasma arginine levels during treatment correlated with types of molecular defects in the arginase genes.

Ca2+ homeostasis in Brody's disease. A study in skeletal muscle and cultured muscle cells and the effects of dantrolene an verapamil

Brody's disease, i.e., sarcoplasmic reticulum (SR) Ca(2+)-dependent Mg(2+)-ATPase (Ca(2+)-ATPase) deficiency, is a rare inherited disorder of skeletal muscle function. Pseudo-myotonia is the most important clinical feature. SR Ca(2+)-ATPase and Ca2+ homeostasis are examined in m. quadriceps and/or cultured muscle cells of controls and 10 patients suffering from Brody's disease. In both m. quadriceps and cultured muscle cells of patients, the SR Ca(2+)-ATPase activity is decreased by approximately 50%. However, the concentration of SR Ca(2+)-ATPase and SERCA1 are normal. SERCA1 accounts for 83 and 100% of total SR Ca(2+)-ATPase in m. quadriceps and cultured muscle cells, respectively. This implies a reduction of the molecular activity of SERCA1 in Brody's disease. The cytosolic Ca2+ concentration ([Ca2+]i) at rest and the increase of [Ca2+]i after addition of acetylcholine are the same in cultured muscle cells of controls and patients. The half-life of the maximal response, however, is raised three times in the pathological muscle cells. Addition of dantrolene or verapamil after the maximal response accelerates the restoration of the [Ca2+]i in these muscle cells. The differences in Ca2+ handling disappear by administration of dantrolene or verapamil concomitantly with acetylcholine. The reduced Ca2+ re-uptake from the cytosol presumably due to structural modification(s) of SERCA1 may explain the pseudo-myotonia in Brody's disease. Single cell measurements suggest a beneficial effect of dantrolene or verapamil in treating patients suffering from Brody's disease.

MR of the caudal regression syndrome: embryologic implications

PURPOSE

To evaluate the spectrum of developmental anomalies observed in patients with the caudal regression syndrome and relate them to the pathogenesis of this syndrome.

METHODS

Nineteen children with caudal regression were investigated with MR.

RESULTS

The level of vertebral agenesis varied from T-11 to S-5. In 9 of the 19 children the characteristic high-ending wedge-shaped cord terminus was observed. A separation of the anterior and posterior spinal roots of the cauda equina was observed in 9 patients. Four patients had a tethered spinal cord, in 1 in combination with a wedge-shaped cord terminus.

CONCLUSIONS

The pathogenesis of the caudal regression syndrome can be divided into two kinds: there is usually a disturbance of the primary neurulation process; in other cases there is a derailment of the process of degeneration and differentiation of an initially normally developed primary and secondary neural tube. MR aids understanding of the morphology and pathogenesis of congenital malformations involved (including the associated anomalies of the genitourinary and gastrointestinal systems), but other studies are still necessary to determine the exact mechanism of this syndrome.

A case of macrocephaly, hydrocephalus, megacerebellum, white matter abnormalities and Rosenthal fibres

The authors report the case of a young boy with macrocephaly, cerebellar symptoms and signs of raised intracranial pressure. Magnetic resonance imaging showed obstruction of the aqueduct, ventricular enlargement of the cerebellum and areas of increased signal intensity in the cerebellar and frontal white matter. A stereotactic biopsy of the cerebellum showed many Rosenthal fibres and glial proliferation. Although the histopathological and neuroradiological findings were suggestive of Alexander's disease, the initial presentation and clinical course were unusual for this diagnosis. The authors suggest that a separate form of Alexander's disease should be distinguished with predominant clinical, neuroradiological and neuropathological cerebellar involvement. This form also seems to have a better life-expectancy.

Zellweger syndrome in a preterm, small for gestational age infant

A preterm (gestational age 34 weeks), small for gestational age infant (birth weight less than P2,3) is described. Because of unexplained slightly disturbed liver function tests at age 2 months, extensive metabolic examinations were performed. Elevated blood levels of very long-chain fatty acids, pipecolic acid and abnormal levels of bile acid intermediates were detected, suggesting a peroxisomal disorder. The plasmalogen content of erythrocytes was decreased. Morphologically distinct peroxisomes were absent in the liver. In fibroblasts an accumulation of very long-chain fatty acids, decreased activity of acyl-CoA:dihydroxyacetone phosphate acyltransferase and impaired de novo biosynthesis of plasmalogens was found. In summary, a mild variant of the classical cerebro-hepato-renal syndrome of Zellweger was found without the characteristic clinical facial signs.

Malformations of the spinal cord in 53 patients with spina bifida studied by magnetic resonance imaging

The incidence of associated malformations of the hindbrain and spinal cord in patients with spina bifida was investigated by a clinical and magnetic resonance study. The incidence of these malformations in combination with spina bifida was 49/53 (92.5%). Fifty-tree children born with spina bifida aperta (40 patients) or spina bifida occulta (13 patients) formed the study group. The incidence of the various malformations were: Chiari malformations, type I, 10/53 (19%), and type II, 20/53 (38%); syringomyelia, 13/53 (24.5%); hydromyelia 4/53 (7.5%); tethered cord malformation, 35/53 (66%); diastematomyelia 2/53 (4%). Thirty-seven of the 49 patients with associated malformations had no clinical signs at the time of our study. The results point to the fact that in the pediatric age group, associated spinal defects often remain asymptomatic.

Infantile isolated sulphite oxidase deficiency: report of a case with negative sulphite test and normal sulphate excretion

We present the clinical and biochemical data of a patient with infantile isolated sulphite oxidase deficiency with late onset of symptoms. A comparison of the biochemical parameters is made with the neonatal type of this disease and with the data of described patients with the combined defect of sulphite oxidase and xanthine oxidase, due to molybdenum cofactor deficiency. False-negative sulphite dip stick test as a pitfall in the diagnosis of sulphite oxidase deficiency is discussed.

Acute hemiparesis as the presenting sign in a heterozygote for ornithine transcarbamylase deficiency

Strokes in children occur in conjunction with cardiac disease, hematological disorders, trauma, intracranial infections and migraine. Recently several inborn errors of metabolism have been recognized as possible causes of stroke-like symptoms. We describe a female heterozygote of ornithine transcarbamylase deficiency, who presented with convulsions and right sided hemiplegia. MR-imaging of the brain demonstrated an acute ischemic lesion in the left hemisphere. In addition to other known metabolic causes of stroke like attacks urea cycle defects should be considered in the differential diagnosis of acute hemiplegia in childhood.

Morphological changes in the human end plate with age

We carried out a light and electron microscopic study on end plates and related structures in external intercostal muscles from subjects aged between 4 and 77 years. Light microscopically end plates maintained the same size, did not increase in number and showed no sprouting of terminal axons, all indicating that major compensatory histological changes to maintain adequate neuromuscular transmission with age were not required. At the ultrastructural level end plates became more complex mainly at the postsynaptic side. The latter included increased length and branching of the postsynaptic membrane with enlargement of the postsynaptic area, and degeneration of junctional folds. However, some neuromuscular junctions (NMJs) showed little branching of the postsynaptic membrane, even in old age. At the presynaptic side nerve terminals with an irregular shape were noted in the aged. Schwann cell processes were seen to intrude into the primary synaptic cleft. From these data we suggest that degeneration of the postsynaptic membrane with consequent focal denervation of NMJs is a primary event in the age-related changes of end plates. The muscle fibres showed a minor degree of type grouping in old age doubtless due to loss of motor neurons with age.

A new case of hyperargininaemia: neurological and biochemical findings prior to and during dietary treatment

We present clinical and biochemical data on a further patient with hyperargininaemia and the results of neurophysiological tests both before and during dietary treatment with an essential amino acid mixture. With normalisation of plasma arginine concentrations, neurological functions improved and brain stem auditory evoked potentials normalized suggesting a partially reversible central conduction disorder. Neuroradiological findings included cerebral cortical atrophy on computed tomography scan and patchy abnormal myelination on magnetic resonance imaging (MRI). The typical clinical picture is discussed with reference to published therapeutical trials.

Moyamoya disease associated with renovascular hypertension

This is a report of a case history of a child with cerebral Moyamoya disease and gradual development of systemic hypertension. Sodium depletion combined with enalapril induced renal failure. A bilateral renal artery stenosis was found. Percutaneous transluminal angioplasty was not successful and was followed by autotransplantation of both kidneys. Histopathological examination of the renal arteries revealed intimal hyperplasia.

A new case of dihydropyrimidine dehydrogenase deficiency

We present the clinical and biochemical features of a boy with dihydropyrimidine dehydrogenase deficiency, which seem to underline a disease entity of developmental retardation, epilepsy and muscular hypertonia.

[The Kleine-Levin syndrome]

Two boys, aged 12 and 13 years, showed relapsing periods of somnolence and excessive eating, starting after a viral illness. One of them also showed periodic disturbance of sexual impulse control. The symptomatic periods were followed by symptom-free intervals in a highly characteristic pattern. This gave the clue to the diagnosis Kleine-Levin syndrome. The cause of this syndrome is unknown, in some cases a relationship between infectious disease or traumatic brain damage has been postulated. A dysfunction of the hypothalamus and associated structures is suspected. The syndrome has a rather favourable prognosis. The symptoms can be relieved by amphetamines, methylphenidate and probably also by lithium carbonate.

[Spinal muscular atrophy in young infants]

Two congenital anterior horn cell diseases may be responsible for neonatal muscular atrophy. The acute Werdnig-Hoffmann disease (SMA-I) has a progressive course, the anterior horn cell degeneration (AHCD) is non progressive in the postnatal period. In case of Werdnig-Hoffmann disease symptoms of hypotonia and muscle weakness may be present at birth, but become progressive during the first months of live. The full clinical picture of AHCD is present at birth. In the latter clinical symptoms of fetal hypokinesia may be noticed during intrauterine life. Histopathological muscle investigation reveals a more or less characteristic neurogenic pattern in Werdnig-Hoffmann disease, in AHCD neurogenic and myopathic changes are variable. Two examples of these diseases will be discussed.

Karyotyping urine sediment cells confirms trisomy 12 mosaicism detected at amniocentesis

A newborn is described in whom trisomy 12 mosaicism was detected prenatally at third trimester amniocentesis during the fourth pregnancy of a 34-year-old woman. After birth, trisomy 12 cells were found in placental tissue and in cultured urine sediment cells. A sample of cord blood and a skin biopsy revealed only normal (46,XX) cells. Both parents had a normal karyotype. After a difficult start with unexplained hypoglycaemias and convulsion equivalents, the girl is doing well at the age of 9 months: there are no signs of central motor disturbance. The importance of the use of cultured urine sediment cells in confirming chromosomal mosaicism is stressed.

A myasthenic syndrome with congenital paucity of secondary synaptic clefts: CPSC syndrome

Two cases of a newly recognized myasthenic syndrome were investigated (CPSC syndrome). The course of the disease was observed for periods of 6 and 3 years. In infancy, exacerbations of the symptoms occurred during febrile illness, but thereafter the clinical course was stable and the children appeared to be only slightly handicapped. Biopsies were taken from the intercostal muscle in both patients. Microelectrode studies revealed small Mepp amplitudes. Light microscopy demonstrated predominance of type I fibers and focal type-grouping. There was a lowered cholinesterase activity and frequent branching of preterminal axons. Electron microscopy revealed that there were few, if any, folds of the postsynaptic membrane and that there were no signs of degeneration. Methods for localization of acetylcholine receptors (AChR) revealed a deficiency and altered distribution of AChRs at these postsynaptic membranes and the occurrence of extrajunctional AChRs in some muscle fibers. It is concluded that the syndrome is a clinicopathological entity, characterized morphologically by a congenital paucity of secondary synaptic clefts (CPSC syndrome).

A congenital myasthenic disorder with paucity of secondary synaptic clefts: deficiency and altered distribution of acetylcholine receptors

Congenital myasthenia (CM) constitutes a heterogeneous group of disorders with different underlying defects. The authors investigated a case of CM, presenting with congenital contractures. Endplate studies in the first year of life showed a developmental disorder of postsynaptic membranes. Clinical follow-up demonstrated a beneficial effect of pyridostigmine, resulting in normal motor development. Results of a second biopsy at age 4 are reported in this paper. Microelectrode study showed small Mepp amplitudes, which returned to nearly normal in the presence of neostigmine. In the electronmicroscope the postsynaptic membranes showed a paucity of infoldings, as in the first biopsy. These membranes showed only scanty, patchy enhancement with two different methods for localization of AChR. The extrajunctional membranes showed evidence of local presence of AChR. Our results show a developmental disorder of postsynaptic membranes with a deficiency and altered distribution of AChRs.

Immunohistochemical localization of acetylcholine receptors at human endplates using a monoclonal antibody

We describe a simple indirect immunohistochemical method for localization of acetylcholine receptors (AChR) in motor endplates at the light and electron microscopic level. This method involves the use of a monoclonal antibody directed against the main immunogenic region (MIR) of AChRs and is applicable to periodate-lysine-paraformaldehyde (PLP)-fixed tissue. We discuss the advantages of this method, as compared with the alpha-bungarotoxin-immunoperoxidase technique, and stress its value for diagnostic investigations of motor point biopsies from patients with neuromuscular transmission disorders.

Muscle weakness and congenital contractures in a case of congenital myasthenia

A case of nonautoimmune, prenatal-onset, congenital myasthenia with congenital contractures including camptodactyly is presented. The clinical features re identical to those in three previously reported cases. In this form of congenital myasthenia, the muscle weakness and congenital contractures may resolve completely after conservative treatment, including anticholinesterase medication. Diagnosis can be made by the characteristic clinical history, neurological assessment, and electromyography with repetitive nerve stimulation.

Progressive dystonia with marked diurnal fluctuation. Report of a case

A 9-year-old girl suffering from progressive fluctuating dystonia is reported. Some problems of diagnosis are discussed. The differential diagnosis is described and a comparison is made with cases from the literature.

Paucity of secondary synaptic clefts in a case of congenital myasthenia with multiple contractures: ultrastructural morphology of a developmental disorder

A new form of congenital myasthenia is described. An infant whose foetal movements during pregnancy had been weak presented at birth with muscle weakness and multiple contractures of the lower limbs. The clinical course was characterised by myasthenic crises during febrile illnesses. Neurophysiological studies demonstrated a decremental response at 2-3 HZ stimulation; this effect was reversed by edrophonium iv. At the age of eight months, a biopsy from the soleus muscle showed a predominance of type I fibres and variation in fibre diameters was slightly increased. Ultrastructural studies of the motor endplates revealed a marked reduction of post-synaptic membrane lengths with paucity of secondary clefts. Signs of focal degeneration were absent. The picture was reminiscent of foetal neuromuscular junctions. A developmental disorder of the postsynaptic membrane was considered to be the basic cause of the neuromuscular transmission defect.

Familial porencephalic white matter disease in two generations

We report the pedigree of a family in which a mother and her two children, a boy and a girl, all suffer from a similar, though variably expressed cerebral disorder, seen on CT as uni- or bilateral cavities within the supratentorial white matter in communication with the ventricular system. Additional white matter hypodensity around the lateral ventricles without ventricular widening provides preliminary evidence of a primary disease of myelination, in the absence of histopathological confirmation. This is probably the first report of "porencephaly" which shows a pattern of autosomal dominant inheritance.

Congenital multiple angiomatosis with brain involvement

A case of congenital multiple angiomatosis with cerebral involvement is presented. Postmortem investigation showed identical angiomas on skin and brain. The cerebral vascular tumor has caused altered vascularization of the hemisphere, resulting in a development arrest of the corpus callosum and a fetal appearance of the parietal and temporal vessels.

Arthrogryposis multiplex congenita due to congenital myasthenia

Decreased fetal movements may cause arthrogryposis multiplex congenita. Several distinct neuromuscular disorders may cause this syndrome, but congenital myasthenia has not previously been considered to be a possible cause. The authors report a case of congenital myasthenia gravis leading to arthrogryposis congenita.