zoonoses and communicable diseases common to ... - PAHO/WHO

CANDIDIASIS 317tion may occur in any organ, it is most frequent in the eyes, kidneys, lung, spleen,and the CNS, as well as around a cardiac value prosthesis or in the bones.The antimycotic recommended for mucosal and skin candidiasis is nystatin; clotrimazoleis also effective. Amphotericin B or fluconazole are used to treat other sites.A cooperative study in 18 medical centers in Europe evaluated the efficacy,harmlessness, and tolerance of oral fluconazole (50 mg/day in a single dose) andof polyenes (oral amphotericin B at 2 g/day or nystatin at 4 million units/day infour or more doses) in preventing mycotic infection. The study included 536patients hospitalized with a malignant disease who were about to receivechemotherapy, radiotherapy, or bone marrow transplants, including patients whoalready had neutropenia or who were expected to develop it. Treatment was administeredfor approximately 30 days. Oral fluconazole proved to be more effectivethan the oral polyenes in preventing buccopharyngeal infection and was equallyeffective in preventing infections in other parts of the body in patients with neutropenia.Side effects were recorded in 5.6% of 269 patients in the group treatedwith fluconazole and 5.2% of 267 patients treated with polyenes. These reactionsled to a discontinuation of treatment in seven patients in each group (Philpott-Howard et al., 1993).The Disease in Animals: Candidiasis in chicks, poults, and other fowl is usuallysporadic. Epidemic outbreaks sometimes occur, particularly in poults, with mortalityranging from 8% to 20%. Avian candidiasis is an infection of the upper respiratorysystem. In young birds it sometimes has an acute course, with nervous symptoms.However, the disease is generally asymptomatic and diagnosis occurspostmortem. The most frequent lesion is found in the crop and consists of plaquesthat resemble curdled milk and adhere lightly to the mucosa. In adult birds, candidiasishas a chronic course and causes thickening of the crop wall, on which a yellowishnecrotic material accumulates. In Israel, a strange epidemic of a venereal diseasein geese that affected many farms was described. The disease began withreddening and tumefaction of the mucosa of the penis or cloaca; the lesion laterbecame gangrenous and a portion of the penis was lost. Examinations indicated amixed flora of bacteria and C. albicans. Experimental inoculation of the bacterialflora did not affect the birds; in contrast, it was possible to reproduce the diseasewith C. albicans isolated from the lesions.Oral candidiasis occurs sporadically in calves, colts, lambs, swine, dogs, cats, laboratorymice and guinea pigs, as well as in zoo animals. Candida spp. can, on rareoccasions, lead to mastitis and abortions in cattle. A systemic disease due to C. albicans,with lesions in various organs, was reported in calves that underwent prolongedtreatment with antibiotics. Skin lesions and thrush have been described in cats.Source of Infection and Mode of Transmission: C. albicans occurs as a componentof the normal flora in the digestive system of a high percentage of healthyindividuals and animals. The yeast is also found in nature.In young fowl, C. albicans is probably a primary etiologic agent, while in mancandidiasis is almost always associated with other diseases. Prolonged treatmentwith antibiotics, cytotoxic agents, and corticosteroids is a predisposing factor. Theuse and abuse of antibiotics over an extended period is an important factor in theproliferation of and later infection by Candida and other fungi, in that they alter thenatural flora of the mucosal surfaces.