Bulbar dysfunction: An early presentation of congenital myasthenic syndrome in three infants.

Congenital myasthenic syndromes are a group of rare genetic disorders affecting neuromuscular transmission. A high index of suspicion is required as clinical manifestations can be variable and nonspecific. Clinical phenotype includes arthrogryposis, respiratory crises, facial deformities, and weakness. With the availability of molecular genetics, this group of conditions can now be more clearly delineated and targeted treatment can be initiated. We describe three children who presented with bulbar difficulties and had Cholinergic receptor, nicotinic, and epsilon or receptor associated protein of the synapse mutations.

Idiopathic intracranial hypertension without papilledema.

Idiopathic intracranial hypertension is characterized by high cerebrospinal fluid pressure with no underlying structural or systemic cause. Idiopathic intracranial hypertension without papilledema, although well-described in adults, is rarely reported in the pediatric population. The usual presentation is similar to that of chronic daily headache, with some features of migraine. However, treatment modalities are different, and specific therapy can lead to significant improvement in symptoms. We describe six children with chronic daily headache, who were diagnosed with idiopathic intracranial hypertension without papilledema. The response to medical management was variable. One child required a lumboperitoneal shunt for persistent signs, with good surgical outcome.

Epidemiologic variability of chronic inflammatory demyelinating polyneuropathy with different diagnostic criteria: study of a UK population.

Epidemiologic data on chronic inflammatory demyelinating polyneuropathy (CIDP) is limited, and previous studies have shown variable results. The frequencies of CIDP subtypes remain unknown. Variations due to use of different diagnostic criteria have not been studied. We examined the prevalence and incidence of CIDP in Leicestershire and Rutland, UK (population 963,600). Prevalence day was 1 May 2008. The prevalence of CIDP fulfilling the 2006 clinical and electrophysiologic European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) criteria was 4.77 per 100,000 (95% confidence interval [CI] 3.49-6.37). Using the 1991 American Academy of Neurology (AAN) criteria, the prevalence was 1.97 per 100,000 in this population (95% CI 1.19-3.08). Lewis-Sumner syndrome was diagnosed in 15.2% of patients, and 23.9% had pure sensory onset. Over 40% required no immunotherapy, and 84.6% of those treated responded. More than 80% of the AAN criteria-negative but EFNS/PNS criteria-positive patients were responsive to treatment. Both sets of criteria were equally likely to identify patients who required therapy. The mean annual incidence rate over the 3 years preceding the prevalence day was 0.70 per 100,000/year using EFNS/PNS criteria (95% CI 0.43-1.08), and 0.35 per 100,000/year using AAN criteria (95% CI 0.17-0.64). We conclude that the AAN criteria may underestimate prevalence and incidence of the disease. The EFNS/PNS criteria provide higher diagnostic sensitivity and are of greater clinical relevance, and they also offer a useful breakdown of the epidemiologic data for CIDP subtypes.

Reye syndrome and reye-like syndrome.

Reye syndrome is an acute metabolic encephalopathy, largely affecting children and adolescents. In Reye-like syndrome, because of inborn errors of metabolism, hypoglycemia, hypoketonemia, elevated ammonia, and organic aciduria are often evident. It is well-known that fatty-acid oxidation defects can present as Reye-like syndrome. The most commonly diagnosed metabolic disorder in association with Reye syndrome has been medium-chain acyl coenzyme A dehydrogenase deficiency. The present consensus seems to be that Reye syndrome is very rare, and that any child suspected of manifesting this disorder should undergo investigations for inborn errors of metabolism. We recently treated a child with "Reye-like illness" who possibly manifested a long-chain acyl dehydrogenase deficiency, and who had also ingested aspirin. We discuss the possible pathogenesis of the disorder in this child. The end results of mitochondrial dysfunction in Reye syndrome and Reye-like illness may be similar.

Sleep-disordered breathing in Chiari malformation type 1.

Type 1 Chiari malformation is defined as an elongation of the cerebellar tonsils >6 mm below the foramen magnum. Central sleep apnea is a well-recognized sign, and can be an initial presentation, of this malformation. Obstructive sleep apnea is not a widely recognized sign of Chiari type 1 malformation, though there were a few case reports. We present a 13-year-old girl who presented at our respiratory clinic with excessive nighttime snoring. Magnetic resonance imaging revealed a Chiari type 1 malformation requiring decompression. We emphasize the importance of including cervicomedullary junction disorders in the differential diagnosis of apnea, and we review the literature concerning mixed apneas and obstructive sleep apneas in Chiari type 1 malformation.

Dystonia during feeding as an early sign of dopa-responsive dystonia.

A 21/2-month-old girl presented with feeding difficulties of 8 weeks' duration. She cried, vomited, arched, and became rigid during every feeding. She was suspected of having gastroesophageal reflux disease. Dystonia and developmental delay became apparent at age 8 months. Nasogastric tube feeding and gastrostomy with Nissen's fundoplication were performed at age 7 and 12 months, respectively. She was treated with baclofen, trihexyphenidyl, and antireflux therapy, without benefit. She became severely developmentally delayed with marked head lag, dystonia, and rigidity. Levodopa therapy was initiated at age 21 months. She manifested dramatic improvement over the next year. Dystonia, rigidity, and retching disappeared soon after treatment. She experienced good catch-up in development. She exhibited poor head control and an inability to reach out at age 21 months, but bottom shuffling was observed at age 26 months, and walking and speaking three-word sentences at age 2 years and 10 months. Pertinent issues relating to signs, pathophysiology, genetics, and biochemical defects are discussed briefly.

Infantile spinocerebellar ataxia type 6: relationship to episodic ataxia type 6.

Spinocerebellar ataxia type 6 is one of the hereditary progressive cerebellar ataxias first described in 1997. Genetic studies have identified the defect as abnormal expansion of CAG trinucleotide repeat in 1 alpha subunit of the calcium channel gene located on chromosome 19p13. The symptomatic individuals have 20 or 23 repeats in contrast to normal individuals who manifest 19 or less CAG repeats. Most of the earlier reports indicate the age of onset of symptoms to be after the third decade. This report presents a patient with episodic symptoms soon after birth, which is unusual, and to our knowledge this is the youngest reported case. The clinical features of spinocerebellar ataxia type 6 are variable. The mode of inheritance and the common symptoms of this condition are also discussed.

Intracranial arachnoid cysts in children: a review of pathogenesis, clinical features, and management.

Arachnoid cysts are developmental anomalies that are most often diagnosed in childhood. They are often discovered as incidental findings found on imaging. Occasionally they may produce symptoms because of expansion or bleeding. There may be underlying maldevelopment of the cortex especially the temporal lobe. There is controversy regarding the role and the type of surgery indicated in its treatment. Recent descriptions of aphasia and attention-deficit disorders associated with these cysts indicate that we do not fully understand this entity. There is also no acceptable explanation for the male preponderance and increased incidence on the left side. The distribution, clinical features, treatment modalities, and some unusual syndromes associated with arachnoid cysts in children are discussed in this review.