GDAP1 mutations in Italian axonal Charcot-Marie-Tooth patients: Phenotypic features and clinical course.

Mutations in the ganglioside-induced differentiation associated-protein 1 (GDAP1) gene have been associated with both autosomal recessive (AR) and dominant (AD) Charcot-Marie-Tooth (CMT) axonal neuropathy. The relative frequency of heterozygous, dominant mutations in Italian CMT is unknown. We investigated the frequency of dominant mutations in GDAP1 in a cohort of 109 axonal Italian patients by sequencing genomic DNA and search for copy number variations. We also explored correlations with clinical features. All cases had already been tested for variants in common axonal AD genes. Eight patients (7.3%) harbored five already reported heterozygous mutations in GDAP1 (p.Arg120Gly, p.Arg120Trp, p.His123Arg, p.Gln218Glu, p.Arg226Ser). Mutations had different penetrances in the families; the onset of symptoms is in the first decade and progression is slower than usually seen in GDAP1-related AR-CMT. We show that the relative frequency of mutations in GDAP was slightly higher than those observed in MFN2 and MPZ (7.3% vs 6.3% and 5.0%). The relatively milder clinical features and the quite indolent course observed are relevant for prognostic assessment. On the basis of our experience and the data reported here, we suggest GDAP1 as the first gene that should be analysed in Italian patients affected by CMT2.

Transient neonatal hyperinsulinemic hypoglycemia and neurological outcome: a case report.

Transient neonatal hyperinsulinemic hypoglycemia (TNHI) is a form of neonatal-onset hyperinsulinism which usually resolves completely in a few days or months. It is secondary to conditions such as maternal diabetes mellitus or intra-uterine growth retardation. Other rare causes of TNHI are perinatal asphyxia and gestational diabetes. Hyperinsulinemic hypoglycemia (HI) is also observed in association with rare metabolic or genetic conditions. It can also occur in newborns without risk factors. TNHI is usually a transient phenomenon. However, some newborns can have prolonged HI that requires treatment with diazoxide, persists for several months and then resolves spontaneously. Neonatal hyperinsulinemic hypoglycemia must be promptly and correctly diagnosed and treated in order to avoid neurological consequences. We describe a case of transient neonatal hyperinsulinemic hypoglycemia in a full-term born without perinatal complications and appropriate for gestational age with an unfavourable neurological outcome.

Arthrogryposis, cholestatic pigmentary liver disease and renal dysfunction: report of a second family.

We report on a boy, born to consanguineous parents, who had arthrogryposis, cholestatic liver disease, and renal dysfunction. The child died at age 2 months, and autopsy showed pigmentary storage disease in liver cells, nephrocalcinosis, and rarefaction of motor neuron cells in the anterior horns of spinal cord. This association, reported in 1979 by Nezelof et al., is a distinctive syndrome. The possibility of an autosomal recessive or an X-linked inheritance is discussed.

Late onset globoid leukodystrophy: unusual clinical and CSF findings.

During a febrile upper respiratory tract illness this 4 year old boy developed left hemiparesis, which progressed to loss of walking and even of sitting finally to tetraplegia. The cerebrospinal fluid protein pattern showed blood-brain barrier damage with additional intrathecal IgG synthesis. The symptoms responded to steroid therapy but resumed and worsened on withdrawal. Only late, when visual evoked potentials and nerve conduction velocity proved to be impaired, was Krabbe disease diagnosed on the assay of cultured fibroblasts for galactocerebroside-beta-galactosidase. We discuss the significance of possible endogenous production of IgG in the CNS.

Secondary generalized epilepsy in childhood: EEG patterns and correlation with responsiveness to benzodiazepines or ACTH (preliminary note).

Secondary generalized epilepsy in childhood, characterized by absences or minor motor seizures, occurs in the forms of various syndromes, as defined by current classifications. EEG often shows continuous or subcontinuous paroxysmal activity associated with partly reversible psychomotor or mental regression. The paroxysmal activity can exhibit one of two distinct patterns: "organized" or "disorganized," although intermediate forms are common. The two patterns differ not only morphologically but also in the responsiveness to drug or hormone therapy, reactivity to stimuli, sleep changes and frequency of disordered slow rhythms. These features are illustrated by means of a survey of 10 cases.