Burkitt's lymphoma of the appendix presented with acute appendicitis and ascites.

Primary appendiceal lymphoma is a rare malignancy, often of the Burkitt subtype, and may present as acute appendicitis. We report a 6-year-old boy with abdominal pain, distension, fever, and a palpable right lower quadrant mass. Laboratory tests showed leukocytosis and hyperkalemia. Abdominopelvic computed tomography revealed an enlarged appendix, moderate ascites, and peritoneal thickening, findings that could be mistaken for perforated appendicitis with an underlying neoplasm and tumor lysis syndrome. Emergency laparoscopic appendectomy with peritoneal drainage was performed. Histopathology confirmed appendiceal Burkitt's lymphoma. This case illustrates the diagnostic challenge of this rare tumor and highlights the importance of imaging and clinical assessment in early recognition and timely surgical management.