Bilateral congenital corneal anesthesia in a patient with SCN9A mutation, confirmed primary erythromelalgia, and paroxysmal extreme pain disorder.
The SCN9A gene codes for the sodium voltage-gated channel NaV 1.7. Gain of function mutations cause pain disorders such as primary erythromelalgia, paroxysmal extreme pain disorder, and small fiber neuropathy. Loss of function mutations lead to congenital insensitivity to pain. We report the case of a 6-year-old girl with a SCN9A mutation who presented with both gain of function and loss of function phenotypes, including congenital corneal anesthesia.
Department of Ophthalmology, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, Québec, Canada.
David Ta
DT
Kim
Department of Neurology, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, Québec, Canada.
Elsa
E
Rossignol
Department of Ophthalmology, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, Québec, Canada.
Kinda
K
Najem
Department of Ophthalmology, Centre Hospitalier Universitaire Sainte-Justine, Université de Montréal, Montréal, Québec, Canada. Electronic address: lhospina@gmail.com.
Luis H
LH
Ospina
D002648:Child; D004916:Erythromelalgia / Q000175:diagnosis / Q000235:genetics*; D005091:Exons / Q000235:genetics; D005135:Eye Protective Devices; D005260:Female; D006801:Humans; D006987:Hypesthesia / Q000175:diagnosis / Q000235:genetics* / Q000628:therapy; D007634:Keratitis / Q000151:congenital* / Q000175:diagnosis / Q000235:genetics / Q000628:therapy; D065346:Lubricant Eye Drops / Q000008:administration & dosage; D020125:Mutation, Missense; D062556:NAV1.7 Voltage-Gated Sodium Channel / Q000235:genetics*; D009824:Ointments; D010146:Pain / Q000175:diagnosis / Q000235:genetics*; D010641:Phenotype; D012007:Rectum / Q000002:abnormalities*
D065346:Lubricant Eye Drops; D062556:NAV1.7 Voltage-Gated Sodium Channel; D009824:Ointments