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A 17-year-old boy presents to the emergency department with severe abdominal pain. Laboratory tests show a deficit in uroporphyrinogen I synthetase and excess δ-aminolevulinate and porphobilinogen in the urine. Which of the following symptoms would most likely also be present in this patient?

(A) Chest pain
(B) Hypotension
(C) Neuropsychiatric disturbances
(D) Polyphagia
(E) Stiff neck
in Biochemistry by

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(C) Neuropsychiatric disturbances
This patient suffers from acute intermittent porphyria (AIP), an autosomal dominant disorder caused by a lack of uroporphyrinogen I synthetase. The buildup of toxic levels of δ-aminolevulinate (ALA) and porphobilinogen lead to the associated symptoms of abdominal pain (more than 90% of cases), neuropathy, high sympathetic tone, and neuropsychiatric disturbances, including anxiety, depression, seizures, and paranoia. AIP almost never presents before puberty, and it can be hard to diagnose because of its acute nature. Untreated, it can lead to paralysis and death.

Answer A is incorrect.
 The differential diagnosis for chest pain is long and includes cardiac, pulmonary, gastrointestinal, and musculoskeletal etiologies. However, attacks of acute intermittent porphyria are not associated with chest pain.

Answer B is incorrect. Due to the high sympathetic tone caused by the pain of the crisis, hypertension may be associated with acute intermittent porphyria, but not hypotension.

Answer D is incorrect. Polyphagia, or greatly increased hunger, is one of the cardinal symptoms associated with diabetes mellitus, not acute intermittent porphyria.

Answer E is incorrect. A stiff neck may be associated with meningeal irritation and can be found in meningitis or with musculoskeletal problems, but it is not found in acute intermittent porphyria.