Myiasis is usually caused by flies of the Calliphoridae family, and Cochliomyia hominivorax is the etiological agent most frequently found in myiasis. The first case of myiasis in a diabetic foot of a 54-year-old male patient in Argentina is reported. The patient attended the hospital of the capital city of Tucuman Province for a consultation concerning an ulcer in his right foot, where the larval specimens were found. The identification of the immature larvae was based on their morphological characters, such as the cylindrical, segmented, white yellow-coloured body and tracheas with strong pigmentation. The larvae were removed, and the patient was treated with antibiotics. The larvae were reared until the adults were obtained. The adults were identified by the setose basal vein in the upper surface of the wing, denuded lower surface of the wing, short and reduced palps, and parafrontalia with black hairs outside the front row of setae. The main factor that favoured the development of myiasis is due to diabetes, which caused a loss of sensibility in the limb that resulted in late consultation. Moreover, the poor personal hygiene attracted the flies, and the foul-smelling discharge from the wound favoured the female's oviposition. There is a need to implement a program for prevention of myiasis, in which the population is made aware not only of the importance of good personal hygiene and home sanitation but also of the degree of implication of flies in the occurrence and development of this disease.
Animals ; Argentina ; Diabetic Foot/*complications/parasitology/pathology ; Diptera/anatomy & histology/classification/*growth & development ; Humans ; Male ; Middle Aged ; Myiasis/*diagnosis/*parasitology ; Ulcer/*complications/parasitology/pathology

Leishmania (L.) tropica is a causative agent of cutaneous leishmaniasis, and occasionally of visceral or viscerotropic leishmaniasis in humans. Murine models of Leishmania infection have been proven to be useful for elucidation of mechanisms for pathogenesis and immunity in leishmaniasis. The aim of this study was to establish a murine model for human viscerotropic leishmaniasis, and the growth pattern of L. tropica was studied in different tissues of BALB/c mice in order to find out whether the parasite visceralizes in this murine model. L. major was used as a control as this species is known to cause a progressive infection in BALB/c mice. L. tropica or L. major was injected into the footpad of mice, and thickness of footpad, parasite loads in different tissues, and the weight of the spleen and lymph node were determined at different intervals. Results showed that L. tropica visceralizes to the spleen and grows there while its growth is controlled in footpad tissues. Dissemination of L. tropica to visceral organs in BALB/c mice was similar to the growth patterns of this parasite in human viscerotropic leishmaniasis. The BALB/c model of L. tropica infection may be considered as a good experimental model for human diseases.
Animals ; *Disease Models, Animal ; Female ; Foot/parasitology ; Humans ; Leishmania major/growth & development ; Leishmania tropica/*growth & development ; Leishmaniasis/*parasitology ; Lymph Nodes/parasitology/pathology ; Mice ; Mice, Inbred BALB C ; Organ Size ; Spleen/parasitology/pathology

Leishmania tropica and L. major are etiologic agents of human cutaneous leishmaniasis. Delayed type hypersensitivity (DTH) is an immunologic response that has been frequently used as a correlate for protection against or sensitization to leishmania antigen. In BALB/c mice, L. tropica infection results in non-ulcerating disease, whereas L. major infection results in destructive lesions. In order to clarify the immunologic mechanisms of these 2 different outcomes, we compared the ability of these 2 leishmania species in induction of DTH response in this murine model. BALB/c mice were infected with L. major or L. tropica, and disease evolution and DTH responses were determined. The results show that the primary L. major infection can exacerbate the secondary L. major infection and is associated with DTH response. Higher doses of the primary L. major infection result in more disease exacerbation of the secondary L. major infection as well as higher DTH response. L. tropica infection induces lower DTH responses than L. major. We have previously reported that the primary L. tropica infection induces partial protection against the secondary L. major infection in BALB/c mice. Induction of lower DTH response by L. tropica suggests that the protection induced against L. major by prior L. tropica infection may be due to suppression of DTH response.
Animals ; Disease Models, Animal ; Ear/pathology ; Female ; Foot/pathology ; *Hypersensitivity, Delayed ; Leishmania major/*immunology ; Leishmania tropica/*immunology ; Leishmaniasis, Cutaneous/*immunology/*parasitology/pathology ; Mice ; Mice, Inbred BALB C