HUMAN MYIASIS WITH EXTENSIVE ANAL INVOLVEMENT – CASE REPORT

Case Presentation A 72-year-old male patient, cirrhotic, former alcoholic, and smoker was admitted with anal pain, purulent discharge, and fever for 3 days. The patient had poor hygiene practices, was alert, but had limited understanding of his condition. On proctological examination, a lesion was observed in the perianal region with an abscess draining a large number of larvae. During the operation, necrotic anal borders and myiasis with a large number of larvae were identified. The larvae were removed, and the necrotic tissue was debrided. Antibiotic therapy and ivermectin were initiated. The following day, larvae continued to exit through the anal canal with feces in the wound. A sigmoidostomy was performed to divert the intestinal flow, along with extensive debridement of the necrotic areas in the anal region, which involved both the internal and external sphincters. The patient was discharged after 6 days. He returned with poor self-care, no dressing change, feces in the surgical wound, and a collapsed colostomy, accompanied by pain and abdominal distension. Intravenous antibiotics and a new surgical intervention were indicated. During the procedure, a colostomy with fecal leakage into the subcutaneous tissue and an abscess extending to the pelvis was found. A terminal colostomy was performed. The patient was transferred to the intensive care unit post-surgery but passed away 4 days later.

Discussion Myiasis is caused by fly larvae in the tissues of living beings. The most common location in humans is the skin, but it can also affect cavities such as the eye, ear, nostrils, anus, and vagina. Infestation is associated with poor hygiene habits, diabetes, alcohol consumption, immunosuppression, psychiatric disorders, and rural populations. Diagnosis is clinical, with local pain or itching associated with the presence of larvae. Treatment involves mechanical removal of larvae, debridement of necrotic tissue, and therapy with ivermectin and antibiotics. In anal myiasis, intestinal diversion may be indicated, especially with extensive debridement in the anorectal region and involvement of the sphincter muscles. The stoma, commonly a loop sigmoidostomy, aids in the healing of the anal region and reduces the risk of wound infection from feces.

Conclusion This case highlights the relationship between the patient's self-care and the onset and progression of anal myiasis. It emphasizes the need for extensive debridement of necrotic areas, larval removal, and the creation of an ostomy to aid in proper wound healing.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
25 April 2025