[Cutanous myiasis caused by Sarcophaga spp. larvae in a diabetic patient]

Abstract

Myiasis is defined as a parasitic infestation of tissues and organs in living vertebrates with dipterous larvae. Infestation with dipterous larvae can occur when flies deposit their eggs or first stage larvae on the host's tissues. Myiasis is seen more frequently in tropical and subtropical countries, especially in rural regions where people are in close contact with animals. Diagnosis of myiasis depends on the demonstration of larvae on the host's tissues or organs. Correct identification of the larvae is important for the initiation of appropriate treatment and establishment of preventive measures. In this report, a case of diabetic wound ulcer complicated with myiasis was presented. A 68 years old male patient with a diabetic wound was admitted to the Hacettepe University Department of Infectious Diseases and Clinical Microbiology, Ankara in July 2013. The patient had a history of insulin-dependent diabetes mellitus over 10 years and hypertension, coronary artery disease and chronic renal failure for several years. His left leg under the knee and his right toe were amputated because of diabetic foot. The infection on his right heel had started as a single, painless ulcer 5 months ago. He had medical advice from a health care provider and used ampicilin-sulbactam for 3 months. However, the wound progressed in spite of the treatment and upon admission to our hospital, he was hospitalized with the diagnosis of diabetic foot ulcer. The C-reactive protein, sedimentation rate, white blood cell count and HbA1c values were found to be high. Piperacillin-tazobactam therapy was started and debridement of necrotic tissue was planned. During the debridement prosedure larvae were observed under the necrotic tissue. Two larvae were collected and delivered to the parasitology laboratory. After morphological examination the larvae washed in distilled water and killed in 70% alcohol and they were taken to the Ankara University Veterinary Faculty, Department of Parasitology for identification. The morphological characteristics of cephalopharyngeal skeleton, anterior spiracles and slits of the posterior spiracles were examined and the larvae were identified as third stage of Sarcophaga spp. Diabetes, coronary artery disease and low socio-economic level as well as the presence of an open, neglected wound were attributed as the most important predisposing factors that led to the development of myiasis in this patient. It should be kept in mind that the diabetic patients with open wounds may develop myiasis especially in the summer months and larvae can cause progressive wound infection.