Primary hyperparathyroidism presenting with acute pancreatitis, complicated by raised IgG-4 and positive Covid-19 IgG antibody

Background

Gall stone and alcohol are the two most common causes of pancreatitis. Other etiologies include trauma, post endoscopic retrograde cholangiopancreatography (ERCP), bacterial, viral, fungal, and parasitic infections, hypertriglyceridemia, medications, and scorpion bite to name a few. Hypercalcemia is a rare cause of acute pancreatitis. Hypercalcemia can be due to primary hyperparathyroidism (PHPT) manifested by raised parathyroid hormone and serum calcium level. In addition acute pancreatitis is a rare presenting complain of PHPT. PHPT can be asymptomatic or present with symptoms of bone pain, kidney stones, nephrocalcinosis, renal failure, peptic ulcer disease, accelerated atherosclerotic heart disease, hypertension and proximal muscle weakness. Osteitis fibrosa cystica is the term for radiologically visible characteristic feature of skeletal involvement.

Case presentation

We report a case of 20 years old male with chief complaint of epigastric and left hypochondrium pain associated with vomiting for two months. Abdominal pain was gradual in onset, radiating to back, and progressive. He also had complains of constipation, blood tinged feces and pain during defecation. Initial lab tests were significant for increased amylase, lipase and a diagnosis of acute pancreatitis was made which was confirmed by CT scan. After ruling out the common etiologies of acute pancreatitis, further investigations for uncommon etiologies revealed increased IgG-4 values suggesting autoimmune pancreatitis. However further investigations were done and it did not meet the diagnostic criteria for autoimmune pancreatitis. Covid-19 IgG antibodies were positive, however patient did not have any other symptoms of Covid-19 and PCR Covid-19 test was negative. Although Covid-19 can cause pancreatitis, given the ongoing pandemic, he might have been asymptomatically infected with Covid-19 and developed immunity. Therefore we did not believe Covid-19 to be the cause of his pancreatitis. Thus a search for other rare etiologies was initiated which revealed serum calcium of 15 mg/dL. Serum parathyroid hormone and urinary calcium were increased several times suggesting primary hyperparathyroidism. DEXA scan revealed osteoporosis.

Conclusion

Hypercalcemia is one of the rare etiologies of pancreatitis. Thus it should be considered as one of the etiologies of acute pancreatitis after ruling out the more common ones. Secondly, this Case report highlights acute pancreatitis as one of the rare presenting complain of primary hyperparathyroidism which may be associated with several times increased IgG-4 values. Covid-19 has been associated with a number of presenting complains and can cause acute pancreatitis, amid the ongoing pandemic physicians should exercise caution to avoid spurious association of Covid-19 with acute pancreatitis or other presenting complains.