Recurrent acute pancreatitis with no identifiable etiology poses a significant diagnostic and therapeutic challenge. Gallbladder sludge is an under-recognized cause of so-called idiopathic pancreatitis and may be missed on routine imaging. We report the case of a 32-year-old male with recurrent acute pancreatitis in whom extensive evaluation, including metabolic, autoimmune, and genetic workup, was inconclusive until repeat fasting ultrasonography revealed gallbladder sludge. The patient subsequently underwent laparoscopic cholecystectomy, following which he remained asymptomatic with no recurrence on follow-up. This case highlights the importance of a systematic etiological evaluation in recurrent pancreatitis and underscores the role of repeat imaging in identifying occult biliary pathology.
Acute pancreatitis; recurrent pancreatitis; gallbladder sludge; microlithiasis; idiopathic pancreatitis; cholecystectomy
Acute pancreatitis is a common gastrointestinal emergency, most frequently caused by gallstones and alcohol consumption. Despite advances in diagnostic modalities, approximately 10–30% of cases remain classified as idiopathic after standard evaluation. Recurrent acute pancreatitis further complicates management, as failure to identify and treat the underlying etiology predisposes to repeated episodes, increased morbidity, and progression to chronic pancreatitis.
Gallbladder sludge, composed of cholesterol monohydrate crystals, calcium bilirubinate granules, and mucin, is increasingly recognized as a clinically significant entity within the spectrum of biliary disease. Although often asymptomatic, it can lead to complications such as biliary colic, cholecystitis, and acute pancreatitis. Its intermittent nature and low echogenicity make it difficult to detect, particularly on non-fasting ultrasonography, leading to underdiagnosis.
This case highlights the importance of considering occult biliary pathology, particularly gallbladder sludge, in patients with recurrent idiopathic pancreatitis.
A 32-year-old male presented with sudden-onset severe epigastric pain radiating to the back, associated with nausea and multiple episodes of vomiting. The pain was partially relieved by leaning forward. There was no history of fever, jaundice, alcohol consumption, recent drug intake, or trauma. He reported a similar episode one year prior, which had been managed conservatively.
On examination, the patient was hemodynamically stable. Abdominal examination revealed epigastric tenderness without guarding or rigidity.
Laboratory investigations showed markedly elevated serum amylase and lipase levels. Liver function tests were within normal limits. Serum calcium and fasting lipid profile, including triglycerides, were normal. Contrast-enhanced CT abdomen demonstrated features consistent with acute interstitial pancreatitis, including pancreatic enlargement and peripancreatic fat stranding, without evidence of necrosis or collections.
The patient was admitted and managed conservatively with intravenous fluids, analgesics, and bowel rest due to intolerance to oral intake.
Initial transabdominal ultrasonography of the abdomen was unremarkable, with no evidence of gallstones, biliary dilation, or pancreatic abnormalities. Given the absence of common etiologies, further evaluation was undertaken.
Autoimmune pancreatitis had been excluded during a prior admission with normal serum IgG4 levels and absence of characteristic imaging findings such as a diffusely enlarged “sausage-shaped” pancreas. Genetic evaluation for hereditary pancreatitis, including mutations in PRSS1, SPINK1, CFTR, and CTRC, was performed and found to be negative. There was no family history suggestive of inherited pancreatic disorders.
Magnetic resonance cholangiopancreatography (MRCP) demonstrated features of acute pancreatitis with peripancreatic edema but did not reveal choledocholithiasis, biliary strictures, or pancreatic ductal anomalies such as pancreas divisum.
In view of recurrent episodes with inconclusive evaluation, a repeat fasting ultrasonography was performed. This revealed echogenic, non-shadowing material within the gallbladder consistent with gallbladder sludge.
The patient showed gradual clinical improvement with conservative management and was transitioned to oral feeding as tolerated. Given the likely biliary etiology of recurrent pancreatitis, interval cholecystectomy was advised.
He subsequently underwent elective laparoscopic cholecystectomy after 10 days. The postoperative period was uneventful. Histopathological examination of the gallbladder revealed features consistent with chronic cholecystitis.
On follow-up over subsequent months, the patient remained asymptomatic with no recurrence of abdominal pain or pancreatitis.
Recurrent acute pancreatitis is defined as two or more distinct episodes of acute pancreatitis with complete clinical and biochemical resolution between episodes. Identifying the underlying cause is essential to prevent recurrence and long-term complications, including chronic pancreatitis and pancreatic insufficiency.
The differential diagnosis of recurrent pancreatitis is broad and includes biliary causes (gallstones, microlithiasis, sludge), alcohol use, metabolic disorders (hypertriglyceridemia, hypercalcemia), anatomical abnormalities (pancreas divisum, sphincter of Oddi dysfunction), autoimmune pancreatitis, and genetic predisposition.
Hereditary pancreatitis is associated with mutations in genes such as PRSS1, SPINK1, CFTR, and CTRC, which disrupt normal trypsin regulation and predispose to premature intrapancreatic enzyme activation. In the present case, the absence of these mutations, along with negative autoimmune and metabolic workup, narrowed the etiology to occult biliary pathology.
Gallbladder sludge is considered part of the spectrum of biliary microlithiasis and may represent an early, reversible stage of gallstone disease. It is frequently missed on routine ultrasonography due to its subtle and transient nature, particularly when imaging is performed in the non-fasting state. Repeat imaging in the fasting state improves sensitivity by allowing bile concentration and better visualization.
Advanced imaging modalities such as endoscopic ultrasound (EUS) have been shown to have higher sensitivity in detecting microlithiasis and sludge and are recommended in selected cases of idiopathic pancreatitis. Studies have suggested that a significant proportion of patients initially labeled as having idiopathic pancreatitis are found to have occult biliary disease on further evaluation.
The pathophysiological mechanism involves transient obstruction of the ampulla of Vater by sludge or microliths, leading to impaired pancreatic ductal outflow, premature enzyme activation, and pancreatic inflammation.
Multiple studies have demonstrated that cholecystectomy significantly reduces recurrence rates in patients with sludge-associated pancreatitis, supporting its role as definitive management. Early intervention is particularly important in recurrent cases to prevent disease progression.
Gallbladder sludge should be actively considered in patients presenting with recurrent acute pancreatitis and negative initial workup. A systematic and stepwise evaluation, including repeat fasting ultrasonography, is essential for identifying occult biliary causes. Early cholecystectomy is an effective intervention that can prevent recurrence and improve long-term outcomes.
Dr. Arjun S DNB Internal Medicine Resident Kauvery Hospital, Chennai.
Dr. Sivaram Kannan Clinical Lead and Chief Consultant Physician Kauvery Hospital, Chennai.
Dr. Joyner Abraham Consultant Minimal Access Surgeon Kauvery Hospital, Chennai.
Dr. Thennarasu Consultant Gastroenterologist Kauvery Hospital, Chennai.
