An Intriguing Case of Expanded Dengue Syndrome With Co-existing Encephalitis, Pancreatitis, and Hepatitis: The Classic Thalamic "Double-Doughnut" Sign Revisited.

The "double-doughnut" sign, though not exclusive to dengue encephalitis, proved crucial in this case, aiding in differentiating from other causes of encephalitis. Recognition of this sign can be pivotal in diagnosing expanded dengue syndrome, facilitating timely and appropriate intervention, and improving patient outcomes. This case also underscores the importance of considering dengue in the differential diagnosis of encephalitis, especially in endemic areas. Also, this case's excellent outcome (both clinically and radiologically) was noteworthy.