Acute intermittent porphyria caused by novel mutation in HMBS gene, misdiagnosed as cholecystitis.

BACKGROUND

Acute intermittent porphyria (AIP) is an autosomal dominant neurovisceral inherited disorder due to a defect in the heme biosynthesis pathway. Misdiagnosis of the porphyrias is not uncommon.

METHODS

We present a case of a 26-year-old female with suspected acute cholecystitis, mental status changes, and seizures. Biochemical and molecular investigations confirmed the diagnosis of AIP by findings of elevated urinary porphobilinogen, 5-aminolevulinic acid, and total porphyrins. DNA molecular testing showed a novel heterozygous mutation (c. 760delC p.L254X) in the exon11 of the HMBS gene. To the best of our knowledge, this is the first report of a misdiagnosis of AIP presenting with acute cholecystitis.

CONCLUSIONS

Clinicians are alerted to consider the possibility of AIP in an adult presenting with an acute abdomen, features of cholecystitis, and neuropsychiatric manifestations.