Novel SBF1 splice-site null mutation broadens the clinical spectrum of Charcot-Marie-Tooth type 4B3 disease.

Four siblings of consanguineous Bedouin kindred presented at infancy with an autosomal recessive syndrome of congenital microcephaly, facial dysmorphism, strabismus, developmental delay and ataxia with positive pyramidal signs. Toward the end of their first decade, they developed areflexia, multiple cranial neuropathies and severe polyneuropathy with progressive muscle weakness, affecting proximal and distal extremities. Physical assessment exhibited kyphoscoliosis, bilateral syndactyly and distal muscle wasting with drop-foot and pes cavus. Magnetic resonance imaging (MRI) showed profound cerebellar atrophy with highly unique findings at the pontine and mesencephalic levels, previously described as "fork and bracket" signs. Genome-wide linkage analysis identified a single ~1.5 Mbp disease-associated locus on chromosome 22q13.33. Whole exome sequencing identified a single novel homozygous deleterious splice-site mutation within this locus in SET binding factor 1 (SBF1). SBF1 missense mutations were shown to underlie Charcot-Marie-Tooth (CMT) type 4B3 disease, a rare autosomal recessive subtype of CMT4. The novel SBF1 null mutation highlights distinct severe phenotypic manifestations, broadening the clinical spectrum of SBF1-related neuropathies: cerebellar and pyramidal signs evident in the first months of life with peripheral polyneuropathy emerging only toward the end of the first decade, together with unique MRI findings.

Infantile bilateral striatal necrosis maps to chromosome 19q.

BACKGROUND: Infantile bilateral striatal necrosis (IBSN) encompasses several syndromes of bilateral symmetric degeneration of the caudate nucleus, putamen, and globus pallidus. Autosomal recessive IBSN is characterized clinically by developmental arrest beginning at age 7 to 15 months, dysphagia, choreoathetosis, pendular nystagmus and optic atrophy, and severe progressive atrophy of the basal ganglia on MRI. OBJECTIVE: To map the gene causing IBSN. METHODS: A 10-cM genome-wide linkage scan was initially performed on five affected and five unaffected individuals. The extended family was included in the analysis to narrow the candidate region. Logarithm of odds (LOD) score was calculated using the SUPERLINK program. RESULTS: Linkage to the chromosomal region 19q13.32-13.41 was established (Z(max) = 6.27 at theta = 0.02 at locus D19S412). Recombination events and a common disease-bearing haplotype defined a critical region of 1.2 Mb between the loci D19S596 proximally and D19S867 distally. CONCLUSION: IBSN maps to the chromosomal region 19q13.32-13.41. The presence of a common haplotype in all the patients suggests that the disease is caused by a single mutation derived from a single ancestral founder in all the families.

Familial infantile bilateral striatal necrosis: clinical features and response to biotin treatment.

BACKGROUND: Infantile bilateral striatal necrosis (IBSN) encompasses several syndromes of bilateral symmetric, spongy degeneration of the caudate nucleus, putamen, and globus pallidus. The familial form of IBSN is rare, and inheritance is either autosomal recessive or maternal. METHOD: The authors describe an Israeli Bedouin kindred in which 15 children born to consanguineous parents were affected with familial IBSN. They evaluated the clinical and radiologic evolution of the disease in 11 patients and the cerebral pathologic findings in one patient. Three of the children were treated with oral biotin 100 mg/day. RESULTS: Inheritance was apparently autosomal recessive. The untreated children had a similar clinical picture including developmental arrest beginning at the age of 7 to 15 months, choreoathetosis, and dysphagia. Pendular nystagmus appeared at a late stage. MRI, performed at various stages of the disease, showed severe basal ganglia atrophy. Postmortem study in one patient showed severe atrophy of the lenticular nuclei with gliosis and loss of neurons. Biotin, 100 mg/day, administered to the proband over a period of 15 months, may have slowed progression. In two other children treatment was initiated earlier and appeared to arrest or improve disease. CONCLUSIONS: Familial infantile bilateral striatal necrosis was inherited as an autosomal recessive trait. Clinical features included developmental arrest, dysphagia, and choreoathetosis. Imaging and pathology showed atrophy and degeneration of the basal ganglia. Oral biotin may have benefited three children.

A new variant of autosomal recessive exfoliative ichthyosis.

We report unusual congenital ichthyosiform dermatosis in 5 of 12 children in two related families of unaffected, consanguineous Bedouin parents. It appeared shortly after birth as a fine peeling of nonerythematous skin on palms and soles. Gradually it evolved into prominent, well-demarcated areas of peeling skin in moist and traumatized regions. The cutaneous manifestations share features of ichthyosis bullosa of Siemens (IBS) and peeling skin syndrome (PSS). Histologic examination revealed orthokeratosis, a thickened granular cell layer, and spongiosis without epidermolytic hyperkeratosis. On electron microscopy there was prominent intercellular edema and numerous aggregates of keratin filaments in basal keratinocytes. This combination of clinical, histologic, and ultrastructural features has not been previously reported in the heterogeneous group of congenital ichthyoses. We suggest that it represents a new variant of exfoliative ichthyosis.

Neurophysiologic studies in congenital insensitivity to pain with anhidrosis.

Thirteen patients with congenital insensitivity to pain and anhidrosis, carrying a mutation at the TRK-A gene, were studied. Neurologic examination revealed vestigial pain sensitivity, suggesting an incomplete involvement of the affected nerves. All 13 patients manifested normal electrophysiologic studies but striking absence of sympathetic skin responses. We suggest the use of the sympathetic skin response test in the clinical evaluation of patients suspected of having congenital insensitivity to pain and anhidrosis.

Melatonin effect on seizures in children with severe neurologic deficit disorders.

PURPOSE: Recently, melatonin has been associated with antiepileptic activity, most probably because of its antioxidant activity as a free radical scavenger. This study aimed to expand the clinical experience with melatonin as an antiepileptic drug (AED) in humans. METHODS: Six children (aged 2-15 years), with severe intractable seizures, were treated with 3 mg of oral melatonin 30 min before bedtime, in addition to their previous AED treatment for 3 months. A diary of clinical seizure activity (time of day, duration, and type) was kept by parents for a month before and during treatment. Five patients underwent a baseline polysomnography, and three also were monitored during melatonin treatment. RESULTS: With the exception of the parents of one child, all reported a significant clinical improvement in seizure activity during treatment, particularly during the night. Sleep studies showed a decrease in epileptic activity in two of the three patients who were monitored during treatment, and a change of sleep efficiency from 84.2% to 89.7% (NS). Improvement in daytime behavior and in communication abilities was reported by parents, although it was not objectively measured. CONCLUSIONS: This clinical observation adds to the growing data showing the antiepileptic effect of melatonin. However, owing to the paucity of well-controlled studies, using melatonin as an AED should be limited to this specific group of patients with intractable seizures.

Congenital insensitivity to pain with anhidrosis (CIPA): the spectrum of radiological findings.

BACKGROUND: Congenital insensitivity to pain with anhidrosis (CIPA) is an exceedingly rare, hereditary, sensory autonomic neuropathy (HSAN). AIM: To evaluate the various skeletal manifestations and cranial CT features in children affected by CIPA. MATERIALS AND METHODS: In the semidesert area of the Negev, the Bedouin tribes constitute a closed society where consanguineous marriages are the custom. This has resulted in a group of 20 children being affected by this rare autosomal recessive HSAN. The skeletal surveys and CT scans of these 20 Bedouin patients, 12 girls and 8 boys, ages ranging between 1 month and 8 years, were retrospectively analysed. Cranial CT scans were performed in ten children because of neonatal hypotonia and psychomotor retardation. The skeletal findings were classified as follows: fractures, joint deformities, joint dislocations, osteomyelitis, avascular necrosis and acro-osteolysis. RESULTS: All 20 patients had fractures of the extremities and acro-osteolysis of the fingers. Six had joint deformities. Three children had recurrent hip joint dislocations and another three had avascular necrosis. Ten patients presented with osteomyelitis of the limbs, acetabulum and scapula. The cranial CT scans disclosed mild brain volume loss with some ventriculomegaly. CONCLUSIONS: CIPA is a severe autosomal recessive condition that leads to self-mutilation early in life and to fractures, osteomyelitis and limb amputation in older children. Mental retardation is common. Death from hyperpyrexia occurs in almost 20 % of patients in the first 3 years of life.

Outcome of infants with unilateral Sturge-Weber syndrome and early onset seizures.

Patients with Sturge-Weber syndrome often present with seizures during the first year of life. Currently, only patients with clinically significant seizures who do not respond to medical treatment are candidates for early epileptic surgery. However, a delay of surgical treatment may result in cognitive deterioration. We studied the correlation between parameters and outcome of seizures to re-examine the criteria for early epilepsy surgery. We performed a retrospective chart review combined with telephone interviews of parents of all Israeli infants with unilateral Sturge-Weber syndrome and early onset seizures, and we examined whether age of seizure onset and seizure intensity were correlated with cognitive level and the degree of hemiparesis at follow-up. We recruited a total of 15 patients with unilateral Sturge-Weber syndrome and early onset seizures, five of whom underwent epilepsy surgery. The mean follow-up period of all the patients was 15 years: six patients had normal intelligence, four had borderline cognitive level, three had mild mental retardation and two had moderate mental retardation. Eight of the ten non-operated patients still experience seizures at follow-up. Cognitive delay was significantly correlated with seizure intensity in the early period, but not with the age of seizures onset, the degree of hemiparesis, or the presence of ongoing seizures. We conclude that high seizure intensity in young patients with Sturge-Weber syndrome is a prognostic marker for mental deterioration.

Congenital insensitivity to pain with anhidrosis (CIPA) in Israeli-Bedouins: genetic heterogeneity, novel mutations in the TRKA/NGF receptor gene, clinical findings, and results of nerve conduction studies.

Congenital insensitivity to pain with anhidrosis (CIPA), a rare and severe disorder, comprises absence of sensation to noxious stimuli, inability to sweat, and recurrent episodes of hyperthermia. It has a relatively high prevalence in the consanguineous Israeli-Bedouins. Clinical studies of 28 patients are reported here. Using the linkage analysis approach, we linked the disease in 9 of 10 unrelated Israeli-Bedouin families with CIPA to the TrkA gene, which encodes the receptor for nerve growth factor. In one family, linkage was excluded, implying that another gene, yet unidentified, is involved. Two new mutations in the tyrosine kinase domain of the TrkA gene were identified in our CIPA patients: a 1926-ins-T in most of the southern Israeli-Negev CIPA patients, and a Pro- 689-Leu mutation in a different isolate of Bedouins in northern Israel. Eight prenatal diagnoses were made in the southern Israeli-Negev Bedouins, two by linkage analysis and six by checking directly for the 1926-ins-T mutation. Three polymorphisms in the TrkA protein kinase encoding domain were also observed.

Alternating hemiplegia of childhood in half-sisters.

We present the family of two girls affected with alternating hemiplegia of childhood who were born to the same mother and different fathers. Previous reports suggested mitochondrial dysfunction as an etiologic mechanism for this disorder. Muscle biopsy, including a measurement of the respiratory chain enzymes, performed in one of the sisters showed no mitochondrial abnormalities. The mode of inheritance is not certain, but an autosomal-dominant gene is most likely.

Congenital insensitivity to pain with anhidrosis: ocular and systemic manifestations.

PURPOSE: To report the incidence and severity of the ophthalmologic manifestations in patients with congenital insensitivity to pain with anhidrosis. METHODS: Fifteen Bedouin children with congenital insensitivity to pain with anhidrosis underwent complete ocular examination, including refraction and assessment of corneal sensation, and a detailed neurologic examination, including measurement of median nerve motor and sensory conduction. Patients with corneal ulcers were treated appropriately. RESULTS: In the 15 children (eight girls and seven boys, with a mean age of 3.75 +/- 2.67 years; range, 9 months to 9 years), corneal sensation was absent in both eyes. Corneal opacities were present in 10 children, five of whom had bilateral corneal opacities. Corneal ulcers were found in seven children, two of whom had bilateral ulcers, and in three children the ulcers recurred. The corneal ulcers were characterized by very poor healing. The surgical procedures included four lateral tarsorrhaphies, two corneal patch grafts, and one penetrating keratoplasty. All the patients had self-inflicted injuries varying from skin ulcers, burns, and bone fractures to autoamputations of fingertips and tongues. Many patients showed delayed healing and repair of bone and skin injuries. All patients had attacks of hyperpyrexia, moderate mental retardation, and hypotonicity with absent superficial sensation to light touch. Results of median nerve motor and sensory conduction studies were within normal limits. CONCLUSIONS: The patients with congenital insensitivity to pain and anhidrosis and absent corneal sensation showed a marked tendency to develop corneal ulcers that healed poorly. Congenital insensitivity to pain and anhidrosis, although rare, should be considered in the differential diagnosis of neurotrophic keratitis.

Multiple de novo MPZ (P0) point mutations in a sporadic Dejerine-Sottas case.

Dejerine-Sottas syndrome (DSS), a severe demyelinating peripheral neuropathy with onset in infancy, has been associated with mutations in either PMP22 or MPZ. Most cases of DSS are caused by a single heterozygous dominant point mutation. We identified three de novo point mutations in MPZ exon 3 in a sporadic DSS patient. These three point mutations occur on the same allele and result in three novel amino acid substitutions: Ile(85)Thr, Asn(87)His, and Asp(99)Asn. Our data raise the question as to the potential mechanism(s) involved in the formation of multiple point mutations at a given locus.

Immune globulins are effective in severe pediatric Guillain-Barré syndrome.

The effect of high-dose intravenous immune globulins was evaluated in an open prospective multicenter study of 26 children with severe Guillain-Barré syndrome. They presented with mild to moderate flaccid weakness of extremities, with cranial nerve involvement (20) and sensory impairment (22). All children rapidly deteriorated in 2-16 days (mean 6) to become bedridden, and 2 children also developed respiratory failure requiring artificial ventilation (Disability Grading Scale 4-5). Immune globulins were then administered at a total dose of 2 gm/kg, on 2 consecutive days, without adverse effects requiring discontinuation of therapy. Marked and rapid improvement was noted in 25 children, who improved by 1 to 2 Disability Grade Scales < or = 2 weeks after the infusion. Twenty were able to walk independently by 1 week, and 1 could be weaned off a ventilator. Eighteen children recovered by 2 weeks. The rest recuperated in a period of four months, including a child who was artificially ventilated for 4 weeks. The uniform rapid improvement and recovery associated with immune globulins contrasts with the slow recovery course in severe natural cases. We conclude that immune globulins are effective and safe in severe childhood-onset Guillain-Barré syndrome and therefore may serve as the initial treatment of choice.

Status epilepticus following intravenous N-acetylcysteine therapy.

A previously healthy 2 1/2-year-old girl developed status epilepticus followed by cortical blindness during intravenous N-acetylcysteine therapy for paracetamol ingestion. The child's vision was almost completely recovered during the 18 months follow-up period. We assume that the cortical blindness was a postictal sequela after prolonged seizure episode, most probably due to respiratory depression induced by N-acetylcysteine.

Ataxia with isolated vitamin E deficiency in four siblings.

We describe 4 siblings of a consanguineous Bedouin family with Friedreich ataxia phenotype in whom low serum vitamin E levels without other indicators of fat malabsorption were detected. Although age of onset and some of the clinical features were alike in all 4 patients, the electrophysiological parameters were markedly abnormal in 2, but normal in the other 2. Erythrocytes revealed both membranous and intracellular evidence of oxidative damage. The mutations described in other families with ataxia with isolated vitamin E deficiency were not detectable, nor was an abnormal single-stranded conformation polymorphism pattern apparent in the three exons at the 3' region of the gene. Vitamin E administration in pharmacological doses improved the neurological condition in 2 patients and also corrected some of the patients' erythrocyte cell abnormalities. The finding of vitamin E deficiency in other cases of Friedreich ataxia phenotype may allow treatment at an early stage of the disease, when large dose Vitamin E therapy may reverse the neurological lesions.

[Neurological symptoms associated with vitamin E deficiency].

Children deficient in vitamin E have various neurologic symptoms. 2 cases representing different mechanisms of this vitamin deficiency are reported. A 15-year-old boy with fat malabsorption due to cystic fibrosis who was diagnosed as being vitamin E deficient (< 0.5 mg/l), had typical neuropathies. On the other hand, a 12-year-old Beduin girl had isolated vitamin E deficiency, as well as neurological symptoms suggestive of Friedrich's ataxia. Vitamin E supplementation by intramuscular injection in the first case and per os in the second led to significant improvement in neurological symptoms.

Demyelinating peripheral neuropathy in merosin-deficient congenital muscular dystrophy.

It has recently been shown that merosin, a laminin variant, is deficient in a proportion of patients with congenital muscular dystrophy. Merosin is a heterotrimer composed of the alpha 2, beta 1, and gamma 1 subunits, and further studies have shown that it is the alpha 2 subunit that is deficient in these patients. Because the alpha 2 subunit is also expressed in S-merosin, found in Schwann cells, we have investigated whether peripheral nerve function is also affected in these patients. Motor nerve conduction velocities and sensory distal latencies were examined in 25 cases of congenital muscular dystrophy and the results correlated with the merosin expression in their muscle biopsies. All but two of the 10 merosin-deficient cases had reduced motor nerve conduction, whereas all the merosin-positive cases had normal results. Analysis of the biopsies of these two cases showed that they produced merosin in reduced amounts, in contrast to all other merosin-deficient patients that produced no or only traces of merosin. Sensory nerve studies showed no difference between the two groups. These results indicate that a peripheral demyelinating neuropathy is a feature of merosin-deficient congenital muscular dystrophy. The fact that the alpha 2 subunits is also expressed in Schwann cells supports the idea that the alpha 2 gene, located on chromosome 6, is the candidate gene for merosin-deficient congenital muscular dystrophy.