Case Report: Expanded dengue syndrome with acute pancreatitis and pericardial effusion in octogenarians, from recovery to fatal shock.

Severe dengue fever (DF) can involve multiple organs, yet acute pancreatitis (AP) and pericardial effusion remain rare and easily overlooked, particularly in elderly patients who often present atypically. This report describes two women in their eighties who developed both complications, underscoring the diagnostic challenges and clinical importance of recognizing these manifestations early. Clinical data, laboratory results, and imaging findings were reviewed retrospectively. The first patient initially presented with fever and urinary symptoms before progressing to severe DF with shock, thrombocytopenia, acute kidney injury, and altered consciousness; computed tomography later confirmed AP and pericardial effusion, and she recovered with supportive care. The second patient presented with out-of-hospital cardiac arrest and multiorgan failure, with imaging demonstrating AP and pericardial effusion consistent with dengue shock syndrome; despite aggressive resuscitation, she died on hospital day two. These cases highlight that dengue-associated AP and cardiac serositis may mimic other acute illnesses or coexist with comorbid conditions in older adults, delaying diagnosis. Early imaging, point-of-care ultrasonography, and close hemodynamic monitoring are essential to identify organ involvement promptly and improve outcomes in this vulnerable population.