A Japanese woman in her 30s presented to the emergency department at midnight with right upper quadrant pain that had lasted for a week. Without a definitive diagnosis, she was prescribed acetaminophen and levofloxacin and discharged. When her pain persisted the next morning, she visited her primary care physician and reported fever and right upper quadrant pain. She was referred back to the emergency department with suspected cholecystitis. The patient's vital signs were stable, including a temperature of 36.6°C. Physical examination revealed right upper abdominal tenderness and a positive Murphy's sign, but no other abdominal tenderness. Laboratory tests showed normal white blood cell count and liver enzymes and a slightly elevated C-reactive protein concentration (2.44 mg/dL). Abdominal ultrasound showed no abnormalities. Further questioning revealed a history of unprotected sex, lower abdominal pain before the right upper quadrant pain, and increased vaginal discharge. Urine polymerase chain reaction confirmed