What documented cases exist of parasites infecting the human pancreas and how were they treated?
Executive summary
Documented parasite involvement of the human pancreas is rare but well described in case reports and small series: most commonly Ascaris lumbricoides migrating into the biliary–pancreatic ducts and causing acute pancreatitis, but also echinococcal (hydatid) cysts, trematodes such as Eurytrema pancreaticum and Fasciola hepatica, and occasional reports implicating Strongyloides; management ranges from conservative pancreatitis care and anti‑helminthics to endoscopic removal or surgery depending on the parasite and complication [1] [2] [3] [4] [5] [6].
1. Ascaris lumbricoides: the most frequently reported cause of parasitic pancreatitis
Multiple case reports and literature reviews identify Ascaris lumbricoides as the leading parasite linked to pancreatitis, especially in endemic tropical regions where worms can migrate from the intestine into the bile and pancreatic ducts and obstruct them, triggering biliary colic, cholangitis, cholecystitis and acute pancreatitis [1] [2] [7]. Reported management follows standard acute pancreatitis care (IV fluids, analgesia, bowel rest) with the addition of anti‑helminthic therapy (albendazole or similar), endoscopic retrograde cholangiopancreatography (ERCP) or endoscopic extraction when worms are visualized in ducts, and surgical intervention when endoscopy fails or in the context of complications like necrosis or unrelieved obstruction [2] [7] [8].
2. Echinococcus granulosus: hydatid cysts in the pancreas and chronic sequelae
Hydatid (Echinococcus) disease very rarely localizes to the pancreas (reported incidence ~0.2% of hydatid cases), producing cystic lesions that can mimic or cause chronic pancreatitis, mass effect, obstructive jaundice or new‑onset diabetes; diagnosis is primarily imaging with serology as an adjunct (ELISA) and confirmed in case reports and series [9] [3] [10]. Treatment typically involves surgical removal or cyst drainage when feasible, often combined with prolonged antiparasitic medical therapy such as albendazole; some reported cases have been managed non‑operatively with albendazole alone when surgery posed high risk [3] [9].
3. Pancreatic flukes and trematodes: Eurytrema, Clonorchis, Fasciola and others
Documented human infections with pancreatic flukes include autopsy and case reports of Eurytrema pancreaticum (e.g., a Japanese autopsy finding of about 15 adult flukes in pancreatic ducts) and case series implicating clonorchiasis and other trematodes in biliary obstruction with secondary pancreatitis [4] [8]. Fasciola hepatica has been reported to cause acute edematous pancreatitis in young patients in case reports, emphasizing that liver‑flukes can extend inflammation into the pancreatobiliary system [5]. Management in these cases has combined parasite‑directed therapy (anthelmintics appropriate for the species) with standard supportive care for pancreatitis and procedural removal or drainage when obstructive lesions occur [5] [8].
4. Strongyloides stercoralis and rare nematode reports
Strongyloides stercoralis has been implicated in a very small number of acute pancreatitis reports; diagnosis is difficult due to low sensitivity of stool tests and limitations of serology, and the literature largely consists of isolated case reports and conference abstracts rather than large series [6]. Reported treatment follows anti‑Strongyloides regimens (ivermectin) alongside pancreatitis care, but published data are sparse and conclusions are limited by case‑report evidence.
5. Outcomes, adjunctive therapies and controversies in management
When parasites cause simple ductal obstruction, decompression and removal (endoscopic or surgical) plus anti‑helminthic therapy usually lead to recovery, while complicated cases such as necrotizing pancreatitis carry high morbidity and require broad measures including antibiotics, necrosectomy and intensive care; imipenem, fluoroquinolones and metronidazole are cited for pancreatic sepsis due to their tissue penetrance in the literature review on Ascaris necrotizing pancreatitis [8] [7]. Preventive public‑health measures (sanitation, animal control for echinococcosis) are emphasized by reviews as central to reducing incidence, and diagnostic challenges (misdiagnosis as idiopathic pancreatitis) mean parasitic causes may be under‑recognized in both endemic and non‑endemic settings [11] [3].
6. Limits of the evidence and where uncertainty remains
The available evidence is dominated by case reports, small series and reviews rather than controlled studies, so estimates of frequency, optimal drug regimens, and long‑term outcomes are imprecise; some claims circulating on social media about exotic pancreatic parasites (for example linking parasites broadly to diabetes) are disputed by parasitologists and lack robust documented cases in many regions, highlighting the need to distinguish rare validated reports (e.g., Eurytrema autopsy cases) from unsubstantiated broad assertions [4] [12].