Aim: To describe an infrequent cause of respiratory distress following appendicitis. Methods: A 13-year old male patient presented to the emergency department with abdominal pain, vomiting and fever for the last 4 days. He reported the intake of oral analgesics previous to his attention in our institution. Upon examination, vitals were: T= 38.5ºC, BP: 90/60, HR: 128 bpm, RR: 28/min and SO2: 98% on room air. Physical evaluation of the abdomen revealed tenderness in the right lower quadrant as well as a non-indurated well defi ned mass. No rebound was present. Th e rest of the physical examination was unremarkable. Results: Blood tests showed a WBC: 29.7 x103 cells/mm3 (N: 81.4% B: 0.1% L: 2.5% E: 0%), Platelets: 370 000, Hb/Hto: 13.6/36%. Among biochemical studies, he presented: Glu: 77 mg/dL, Urea: 202 mg/dL, Cr: 0.6 mg/dL, Na: 135mmol/L, K: 3.9mmol/L and Cl: 107mmol/L. On further evaluation, the abdominal U/S showed an appendicular mass (6 cm x 5cm) with minimal free fl uid and thus, the patient was admitted for medical management with Ceft riaxone and Metronidazole. Nonetheless, on day 2 of hospitalization, despite the use of broad-spectrum antibiotics, the patient continued febrile and developed severe respiratory distress and diff use abdominal rebound. A secondary peritonitis was suspected and he underwent emergent surgery. During this procedure, a large appendicular abscess was noted (300cc of pus) and evacuated. Bacterial cultures were positive for E. coli; and antibiotics were tailored. Aft er surgery, the patient persisted with respiratory distress (SO2: 84%), for which a thoracic CT scan was ordered, revealing a large pleural eff usion without underlying pneumonic focus. Aft er a placing a chest tube, pleural fl uid samples were analyzed for potential bacteria, fungus and TB; resulting positive for E. coli. Th e patient had a progressive improvement of his clinical status and aft er completing his antibiotic course (21 days), the chest tube was removed and he was discharged home. Discussion: Th oracic empyema following acute appendicitis is a rare complication. Despite early antibiotic treatment, prompt evaluation of appendicitis and recognition of its potential complications are pivotal, in order to prevent adverse outcomes.