Clinical, electrophysiological, and molecular findings in early onset hereditary neuropathy with liability to pressure palsy

Abstract

Clinical suspicion of HNPP even when nerve conduction study results do not fulfill HNPP criteria should indicate genetic testing. In our patients, early-onset HNPP was associated frequently with isoleucine92valine LITAF polymorphism.

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

“…An inverse correlation between age of onset and frequency of relapses has been reported suggesting a poorer long-term prognosis for those with earlier onset of the disease [35]. A deletion in the PMP22 gene as the causal mutation of HNPP has been recognized for some time but recently an identified polymorphism in LITAF gene was found in several HNPP cases, suggesting that a "double hit" could explain the very early onset of HNPP in some pediatric cases [29]. None of our cases had LITAF gene sequencing done.…”

Pain in hereditary neuropathy with liability to pressure palsy: An association with fibromyalgia syndrome?

“…In our study, the majority of HNPP patients ( n = 20; 62.5%) had an evolution of symptoms from painless mononeuropathy to neuropathic or musculoskeletal pain rather than pain early on, though this pattern was not demonstrated clearly in the subset of patients diagnosed with FMS. The idea that painful symptoms appear later in the course of the disease is supported by a recent case series involving patients with onset of symptoms before age 18, none of whom reported pain .…”

Partial Gene Deletions ofPMP22Causing Hereditary Neuropathy with Liability to Pressure Palsies

“…This final EMG result prompted us to further carry out molecular studies to confirm the diagnosis. As mentioned in Chromik et al [8], genetic testing for patients with clinical suspicion of HNPP even when nerve conduction study results do not prefer HNPP could help physicians to diagnose HNPP in childhood. Future work will need to examine whether the PMP22 gene dosage is regulated by the copy number change in the promoter region as well.…”