Primary Hyperparathyroidism-Induced Acute Pancreatitis: Case Report and Systematic Review

BACKGROUND: Primary hyperparathyroidism (PHPT) is a rare but notable metabolic cause of acute pancreatitis (AP). Early diagnosis and surgical intervention are crucial to prevent recurrence and improve prognosis. METHODS: We retrospectively analyzed the clinical data of a 61-year-old male presenting with AP and severe hypercalcemia (3.54 mmol/L) as the initial manifestation of PHPT. Additionally, a systematic review of 83 studies published between 1958 and May 2026 was performed in accordance with PRISMA guidelines. Individual patient data (IPD) on demographics, total serum calcium levels, treatment modalities, and clinical outcomes were extracted. RESULTS: The patient's total serum calcium was 3.54 mmol/L (14.16 mg/dL) with a parathyroid hormone (PTH) of 640.5 pg/mL. Unenhanced abdominal computed tomography (CT) confirmed acute pancreatitis (AP; moderately severe acute pancreatitis according to the Revised Atlanta 2012 classification), and a left inferior parathyroid adenoma was identified via cervical ultrasonography and 99mTc-MIBI scintigraphy. Total serum calcium normalized following parathyroidectomy (PTX), with resolution of symptoms. A systematic review of 107 patients with primary hyperparathyroidism-associated pancreatitis (PHPT-AP) showed the median age was 38 years (IQR 26-56, range 11-88), 41.1% male, and the median peak total calcium was 3.25 mmol/L (IQR 2.98-3.82, range 2.55-5.36). PTX was performed in 88.8% of the cases. CONCLUSION: PHPT is a treatable cause of acute pancreatitis and should be considered in cases of idiopathic or recurrent pancreatitis. Routine screening of total serum calcium and PTH levels is recommended for idiopathic or recurrent AP. For PHPT-AP patients with hypercalcemic crisis (>3.75 mmol/L or >15 mg/dL), early parathyroidectomy after medical stabilization (traditionally recommended within 72 hours, although modern evidence supports optimization over 48 hours up to 1 week) is safe and curative. For severe but non-crisis PHPT-AP (such as our index case with peak calcium 3.54 mmol/L), definitive parathyroidectomy should be scheduled during the same hospitalization or within 2-4 weeks after pancreatitis resolution. Among 99 survivors, 75 had explicit follow-up records with no pancreatitis recurrence reported; quantifiable follow-up duration was available for 36 of these patients (median 18 months, IQR 6-36).