RESUMEN
Introduction: Postorgasmic illness syndrome (POIS) is characterized by allergic symptoms and flu-like illness after ejaculation. There are still no effective treatments for POIS. Aim: To report the first case of washed microbiota transplantation (WMT) to treat patient with POIS. Methods: Data were collected from a patient with POIS who had received 3 courses of WMT: self-rating scale of POIS symptoms, Self-rating Anxiety Scale, Self-rating Depression Scale, and Symptom Checklist 90. The patient's stool samples for 16sDNA sequencing were collected 1 month after WMT. Results: POIS symptoms improved after WMT. Scores decreased from baseline after WMT: self-rating scale of POIS symptoms (before WMT, 16; after first, 16; after second, 8; after third, 9), Self-rating Anxiety Scale (45, 42.5, 37.5, 45), Self-rating Depression Scale (63.75, 58.75, 47.5, 50), and Symptom Checklist 90 (143, 140, 109, 149). Characteristics of the patient's gut microbiota changed. At the genus level, the relative abundance of beneficial bacteria increased, and some opportunistic pathogenic bacteria decreased. Conclusion: WMT may be an effective and safe choice for the treatment of patients with POIS by changing the gut microbiota of the host.