Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0016382 (flushing)
 6,387 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Paroxysmal extreme pain disorder (PEPD), previously known as familial rectal pain (FRP, or OMIM 167400), is an inherited condition characterized by paroxysms of rectal, ocular, or submandibular pain with flushing. A genome-wide linkage search followed by mutational analysis of the candidate gene SCN9A, which encodes hNa(v)1.7, identified eight missense mutations in 11 families and 2 sporadic cases. Functional analysis in vitro of three of these mutant Na(v)1.7 channels revealed a reduction in fast inactivation, leading to persistent sodium current. Other mutations in SCN9A associated with more negative activation thresholds are known to cause primary erythermalgia (PE). Carbamazepine, a drug that is effective in PEPD, but not PE, showed selective block of persistent current associated with PEPD mutants, but did not affect the negative activation threshold of a PE mutant. PEPD and PE are allelic variants with distinct underlying biophysical mechanisms and represent a separate class of peripheral neuronal sodium channelopathy.
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PMID:SCN9A mutations in paroxysmal extreme pain disorder: allelic variants underlie distinct channel defects and phenotypes. 1714 94

The patient was a 51-year-old man who had been prescribed carbamazepine for right third-branch trigeminal neuralgia. He had stopped taking the medication after the neuralgia resolved. When the neuralgia recurred, he resumed medication, and about 1 month later he developed fever, fatigue, cervical lymphadenopathy, generalized skin flushing, facial edema and perioral vesicles, and was admitted to Ichikawa General Hospital, Tokyo Dental College. Oral findings showed reddening and erosion of the buccal mucosa. Routine laboratory examination revealed leukocytosis and hepatic dysfunction. Human herpesvirus 6 antibody titer remarkably increased during development of eruptions. These findings led to a diagnosis of drug-induced hypersensitivity syndrome. Carbamazepine was discontinued, and prednisolone (30 mg/day) was started and tapered based on improvement of symptoms. Because skin symptoms recurred after he was discharged 15 days after admission, the dose of prednisolone was increased and the symptoms finally disappeared. The patient has experienced no further recurrence.
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PMID:A case of drug-induced hypersensitivity syndrome due to carbamazepine. 2198 95