Abstract
Background A 3-month-old male infant presented, beginning on the second day of life, with paroxysmal painful events that started with tonic contraction of the whole body followed by erythematous harlequin-type color changes.Investigations Screening of the SCN9A gene, which encodes the voltage-gated sodium channel Na V 1.7, identified a new mutation, Gly1607Arg, located within the domain IV S4 voltage sensor. Whole-cell patch-clamp analysis demonstrated functional effects of the mutant channel that included impaired inactivationg-a hallmark of paroxysmal extreme pain disorder (PEPD).Diagnosis The patient was diagnosed as having PEPD, an autosomal dominant disorder characterized by severe rectal pain triggered by defecation or perineal stimulation, usually followed by ocular or submaxillary pain. Erythematous flushing, sometimes in a harlequin pattern, can be a prominent feature of this condition.Management Treatment with carbamazepine (10 mg/kg/day) for g-3 months was ineffective in this case, and the parents made a decision to discontinue the drug. The mother was instructed to avoid painful stimuli that could trigger an episode.
| Original language | English |
|---|---|
| Pages (from-to) | 51-55 |
| Number of pages | 5 |
| Journal | Nature Reviews Neurology |
| Volume | 7 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 2011 |
Bibliographical note
Funding Information:Written consent for publication was obtained from the patient’s parents. We are grateful to Dr Caroline Espil-Taris for help in the diagnosis and treatment of our patient, and to Lynda Tyrrell for technical assistance. This work was supported in part by the Rehabilitation Research Service and Medical Research Service, Department of Veterans Affairs, and the Erythromelalgia Association. The Center for Neuroscience and Regeneration Research is a Collaboration of the Paralyzed Veterans of America and United Spinal Association with Yale University.