Objective: To measure nitric oxide gas directly in the uterus of healthy women and patients with suspected pelvic inflammatory disease.
Design: Pilot case-control study.
Setting: The emergency department of a university hospital.
Patient(s): Twenty premenopausal, nonpregnant women from 18 to 48 years of age with lower abdominal pain and nine healthy women with regular menstrual cycles were included.
Intervention(s): We measured nitric oxide levels in air incubated for 5 minutes in a catheter balloon in the uterine cavity.
Main outcome measure(s): Intrauterine nitric oxide concentration in controls and patients.
Result(s): In patients with lower abdominal pain, nitric oxide was almost 100-fold increased in those in whom pelvic inflammatory disease had been diagnosed compared with those in whom appendicitis had been diagnosed with no individual overlap. Uterine nitric oxide levels were uniformly low in healthy women throughout the menstrual cycle, compared with those with pelvic inflammatory disease.
Conclusion(s): Nitric oxide gas can be measured directly in the uterine cavity with a fast, simple, and safe method. The levels of nitric oxide are increased in patients with pelvic inflammatory disease.