Whole exome sequencing establishes diagnosis of Charcot-Marie-Tooth 4J, 1C, and X1 subtypes.

BACKGROUND: Charcot-Marie-Tooth (CMT) hereditary polyneuropathies pose a diagnostic challenge. Our aim here is to describe CMT patients diagnosed by whole exome sequencing (WES) following years of fruitless testing. METHODS/RESULTS: Three patients with polyneuropathy suspected to be genetic in origin, but not harboring PMP22 gene deletion/duplication, were offered WES. The first patient, a 66-year-old man, had been suffering from progressive weakness and atrophies in the lower and upper extremities for 20 years. Due to ambiguous electrophysiological findings, immune therapies were administered to no avail. Twelve years after PMP22 deletion/duplication testing, WES revealed two pathogenic variants in the FIG4 gene (p.Ile41Thr and p.Phe598fs, respectively), as a cause of CMT 4J. The second patient, a 19-year-old man, had been suffering from hearing and gait impairment since at least his infancy, and recently presented with weakness and dystonia of the lower extremities. In this patient, WES identified the p.Leu122Val LITAF gene variant in heterozygous state, suggesting the diagnosis of CMT 1C, several years after initial genetic analyses. The third patient, a 44-year-old man, presented with progressive weakness and atrophies of the lower and upper extremities since the age of 17 years old. In this patient, WES identified the hemizygous p.Arg164Gln pathogenic variant in the GJB1 gene, establishing the diagnosis of CMT X1, 8 years after testing for PMP22 deletion/duplication. CONCLUSION: Novel diagnostic techniques, such as WES, offer the possibility to decipher the cause of CMT subtypes, ending the diagnostic Odyssey of the patients and sparing them from unnecessary and potentially harmful treatments.

Retroperitoneal schwannomas: dilemmas in diagnostic approach and therapeutic management.

INTRODUCTION: Schwannomas are rare tumors arising from Schwan cells of the peripheral nerve sheath. The majority of the cases are sporadic and familial clustering is often observed in association with von Rechlinghausen's disease. Cases of intrasacral (osseous) and spinal tumors have also been described. Histologically, schwannomas are distinguished by the presence of areas of high and low cellularity called Antoni A and B tissue, respectively. CLINICAL PRESENTATION: Clinical features are highly non-specific and depend on the location and size of the lesion, with abdominal pain and neurological deficit being the most common abnormalities. Radiological studies are fundamental in the diagnostic evaluation of RSs. THERAPEUTIC MANAGEMENT: Despite recent research on the therapeutic strategies against RS, surgical resection appears the only potentially curative approach. Unfortunately, a mere minority of patients is eligible to undergo surgical intervention. In addition, surgical removal of RS does not necessarily guarantee patient's long-term survival. Laparoscopic approach and enucleation of the tumor have been suggested as well. Alternative therapies, such as radio- and chemotherapy often proved insufficient. The aim of this review was to evaluate the results of surgical treatment for RS with special reference to the extent of its histological spread and to analyze the recent literature in order to provide an update on the current concepts of therapeutic management of this entity.