The value of Doppler ultrasound in diagnosis in 25 cases of furunculoid myiasis

Abstract

Background The larvae of the botfly Dermatobia hominis cause furunculoid myiasis in endemic areas. Lack of knowledge of this condition outside these areas leads to confusion in diagnosis and delays appropriate treatment. Objective To describe the clinical findings of furunculoid myiasis encountered in Quintana Roo, in the south-east of Mexico. Materials and methodsWe performed an observational study on 25 cases diagnosed over a period of 4 years.Results Diagnosis of furunculoid myiasis was made in 14 males and 11 females with an average age of 24.5 years. Most of our patients were students, farmers, or housewives. The number of lesions varied from one to four. In 20% of cases, more than one parasite was present in each lesion. The scalp was the most commonly affected region (40%), followed by the trunk and the extremities. Doppler ultrasound study (DUSG) of the furuncle-like lesions confirmed the clinical diagnosis in all cases.Conclusions Furunculoid myiasis is frequent in the state of Quintana Roo, Mexico. We found no association with occupation, gender, social background or age. DUSG can be used to evaluate the number of parasites per furunculoid lesion avoiding misdiagnoses and treatment delays.

Myiasis

“…High-frequency probes are more reliable for the diagnosis of furuncular myiasis. Color Doppler sonography, which is able to visualize the continuous movement of internal fluids of the larva, has proven to be useful for the detection of D. hominis and C. anthropophaga larvae when ultrasound is not able to detect the parasite (279,286). Mammography of breast myiasis may not be able to exclude malignancy (81).…”

“…Ivermectin may kill the larva inside the lesion, with a consequent inflammatory reaction (279). Antibiotics should be used only if there is a bacterial infection.…”

First report of furuncular myiasis caused by the larva of botfly, Dermatobia hominis, in a Taiwanese traveler

“…However, tungiasis is often observed on the toes and soles of the foot [16,17] , where furuncular myiasis caused by D. hominis is rarely found. Although medical device of ultrasonography and dermoscopy have been described as an aid in the diagnosis of furuncular myiasis caused by D. hominis [18,19] , diagnosis is made primarily on clinical observation of furuncle-like skin lesion with particular attention to the patient's travel history.…”

Painful, slow developing abscesses. Furuncular miyasis due to double skin infestation by Dermatobia hominis

“…1 Ultrasound evaluation has been used in endemic areas, demonstrating sometimes more than one larva in a single boiled lesion. 5 In primary infested hosts, an inflammatory reaction begins slowly, the neutrophils being the main inflammatory cells, eosinophils being scarce. The reaction progresses with time, developing a necrotic halo around the larvae containing inflammatory cells surrounded by fibroblasts.…”