A 31-year-old man with a fever and abdominal pain for 3 days presented to the emergency department. Upon arrival, his vital signs were temperature 38.2°C, pulse rate 131 beats/min, respiratory rate 18 breaths/min, and blood pressure 138/63 mmHg. Physical examinations revealed icteric sclera, right upper quadrant (RUQ) tenderness elicited on deep palpation, and suprapubic region tenderness. Laboratory examination results were white blood cell (WBC) count 19,800/mm³, platelet count 58,000/mm³, glucose 730 mg/dL, creatinine 3.9 mg/dL, aspartate aminotransferase 754 IU/L, total bilirubin 20.4 mg/dL, and C-reactive protein > 250 mg/L (reference value < 3 mg/L). A urinalysis showed WBC > 100 per high power field (HPF), red blood cells > 100/HPF, and bacteria. Radiography of the chest and abdomen revealed a mottled collection of gas over the RUQ, and beaded necklace-like air over the urinary bladder area (Fig. 1A). Computed tomography (CT) of the abdomen disclosed a large (19.0 × 10.0 × 17.7 cm) gas-producing liver lesion and intraluminal air within the wall of the urinary bladder (Fig. 1B). Because we suspected a pyogenic liver abscess, emphysematous cystitis, and diabetes mellitus, the patient was treated empirically with a parenteral antibiotic (flomoxef: 1 g every 8 hours) for 28 days, percutaneous drainage of his liver abscess, and insulin to control his blood sugar. Three days later, two sets of blood cultures, drained pus, and a urine specimen grew Klebsiella pneumoniae, which was resistant only to ampicillin, but susceptible to amikacin, ciprofloxacin, ceftazidime, flomoxef, cefuroxime, cefazolin, gentamicin, and piperacillin/tazobactam. After 1 month, his clinical condition stabilized, he was discharged on a regimen of oral cefixime (100 mg three times daily) for 2 weeks, and his 2-month outpatient follow-up was uneventful.