Case Report: Pansteatitis with sterile nodular panniculitis (SNP) in a dog.

A 3-year-old, castrated male Jindo dog presented with a 5-day history of pyrexia, lethargy, anorexia, and abdominal pain. Physical examination revealed multiple subcutaneous nodules, and abdominal ultrasonography showed numerous intra-abdominal nodules. Computed tomography (CT) identified widespread subcutaneous fatty nodules with fat stranding and multiple poorly defined nodular lesions within the abdominal fat. Histopathological examination confirmed panniculitis and steatitis, with no infectious agents identified. Based on these findings, a final diagnosis of sterile nodular panniculitis (SNP) and pansteatitis was made, and the dog was treated with glucocorticoids. Follow-up CT performed 4 months after the initiation of therapy showed marked improvement in the subcutaneous nodules, with only a few residual intra-abdominal lesions remaining. As the dog remained clinically asymptomatic, glucocorticoid therapy was discontinued. At the time of writing, no clinical recurrence had been observed. This is the first reported case in which sterile nodular panniculitis and pansteatitis were diagnosed and treated using minimally invasive approaches, including whole-body computed tomography and laparoscopic biopsy.