Hereditary neuropathy with liability to pressure palsy (HNPP) in childhood: A case study emphasizing the relevance of detailed electrophysiological examination for suspected HNPP in the first decade

Hereditary neuropathy with liability to pressure palsies in childhood: Case series and literature update

“…A history of trivial trauma such as minor compression or physical exercise to explain the neuropathy can be found in 2/3 patients with HNPP [15]. Reports and series of HNPP in children are rare [16][17][18]. Here we report the largest childhood series of HNPP to our knowledge, review the published reports of HNPP in children and compare our data with the reports from the literature review.…”

Partial Gene Deletions ofPMP22Causing Hereditary Neuropathy with Liability to Pressure Palsies

“…The patient, in whom HNPP was identified during the first decade of life, was revealed to have a novel deletion in the promoter region (exon 1b) of PMP22 . Since there have been only a small number of HNPP cases reported during childhood, clinical suspicion of the disease is often low and the symptoms may be overlooked and detailed testing to definitively rule out HNPP is often not performed [2, 3]. To further complicate the diagnosis, the EMG in children is rather difficult to perform, making genetic testing warranted only for patients with possible HNPP.…”

“…Because the symptoms of HNPP most commonly develop in adolescence or adulthood, only a few cases of childhood-onset HNPP have been reported [2, 3]. In children, other conditions may also interfere with the diagnostic accuracy of electrophysiological testing, and molecular genetic studies are needed to confirm the disease.…”

Brachial Plexopathy as Early Manifestation of Hereditary Neuropathy with Liability to Pressure Palsy (Hnpp) in Infancy

“…The amplified fragments were analyzed with automated DNA sequencing by capillary electrophoresis and showed a hybridization pattern compatible with the presence of reduced PMP22 gene dosage (deletion). subject to compression or entrapment, such as the external popliteal sciatic nerve at fibular head, ulnar nerve at the elbow, radial nerve at the humerus and/or the armpit or median nerve in the carpal tunnel [7,9,10]. However, any peripheral or even cranial nerve could be affected.…”

“…The anamnesis data -even without a previous familiar diagnosis-guided to the possibility of a hereditary polyneuropathy. For this reason, molecular and neurophysiological study was mandatory [7]. The neurophysiological studies showed a characteristic Normalized ratio (relative copy number, RCN) electroneurogram in the patient as well as in the affected relatives: signs of generalized sensitive and motor polyneuropathy showing higher expressivity in usual focal compression places whose specificity allows differential diagnosis with other polyneuropathies [11].…”