Acute Intermittent Porphyria Presenting as Refractory Hyponatremia, Seizures, and Paralytic Ileus Following Laparoscopic Appendectomy: A Case Report

describing AIP precipitated by laparoscopic appendectomy, presenting with refractory hyponatremia, paralytic ileus, and new-onset seizures. Case DesCription Patient History and Presenting ComplaintsA 27-year-old male, previously healthy with no known comorbidities or prior hospitalizations, underwent laparoscopic appendectomy introDuCtion Acute intermittent porphyria (AIP) is the most common of the acute hepatic porphyrias, with an estimated prevalence of 1-2 per 100,000 in the general population, though the true prevalence of latent gene carriers is considerably higher (estimated 1 in 1,000). 1 It is caused by a heterozygous pathogenic variant in the hydroxymethylbilane synthase (HMBS) gene encoding porphobilinogen deaminase (PBGD) (PBGD; EC 4.3.1.8),resulting in approximately 50% reduction in enzyme activity and consequent accumulation of neurotoxic heme precursors-δ-aminolevulinic acid (ALA) and PBG-during acute attacks. 2 Acute attacks present with neurological, autonomic, and visceral manifestations, including abdominal pain, neuropathy, psychiatric symptoms, hypertension, tachycardia, seizures, and hyponatremia due to the syndrome of inappropriate antidiuretic hormone secretion (SIADH).3 Recognized triggers include fasting, alcohol, hormonal fluctuations, infections, and-critically-certain anesthetic agents and medications commonly used in the perioperative setting.4 The overlap of AIP symptoms with common surgical and medical diagnoses frequently results in delayed recognition, sometimes over years, during which patients may receive potentially porphyrinogenic drugs that can worsen the condition.5 To our knowledge, only a limited number of cases have been reported in the Indian critical care literature 1-