Pinworm infection – Ovulation at midnight

A 6-year-old girl presented to the emergency department after experiencing genital pain, which had lasted for a few hours, in the middle of the night. A physical examination revealed a moving filamentous object (length: about 7 mm) on her external genitalia. The sharp pain disappeared when the object was removed. By using light microscopy, it was identified as an ovulating female pinworm that had produced a large number of chained fertilized eggs (Video S1 in the online version at DOI: 10.1016/j. idcr.2017.03.005), and many elliptical eggs were confirmed in the worm’s body (Fig. 1). The pinworm died naturally several minutes later. The patient was living with her parents, and they shared the bedding. We advised the patient’s family to improve their domestic hygiene, e.g., to change their bed sheets and clothes frequently, and prescribed pyrantel pamoate on the day of the incident and again two weeks later. No intra-familial transmission occurred, and the treatment was a success.