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

316 MYCOSESevaluating the growth of the strain in nine agar plates with various biochemical compositionsin order to differentiate the strains for epidemiological purposes.Geographic Distribution: Worldwide. There are no delimited endemic zones.Occurrence in Man: It is the most frequent opportunistic mycosis. Its incidencehas increased in recent years due to the increase in prolonged treatments with antibioticsand corticosteroids. Candidiasis is a sporadic disease; epidemics have occurredin nurseries, particularly among premature babies in intensive care units; some epidemicsare due to the use of contaminated medicinal solutions or parenteral feedingfluids. It is estimated that the disease is responsible for nearly one-quarter ofmycotic deaths. In a general hospital in Mexico, candidiasis lesions were found in5.4% of random autopsies conducted (González-Mendoza, 1970).Occurrence in Animals: The disease has been confirmed in numerousmammalian and avian species. Moniliasis in chicks and poults is common andsometimes has economic implications. Outbreaks have been described in variousparts of the world.The Disease in Man: Candida is found as a commensal in the digestive tract andvagina of a high percentage of healthy individuals. Diaper rash and cheilitis (lipsores) are often caused by Candida. In adults, candidiasis is always associated withdebilitating diseases or conditions, such as diabetes (which particularly favorssuperficial candidiasis), AIDS, tuberculosis, syphilis, cancer, obesity, and others.The agent often is responsible for intertrigo of large skin folds, balanitis, and onychiawith paronychia (especially in women whose work frequently requires them toimmerse their hands in water).The most frequent form of the mucosal infection presents clinically as a mycoticstomatitis (thrush) characterized by lightly adhering white plaques on the tongueand other parts of the mouth that can leave a bloody surface when removed. Somehave observed that this clinical form increased in asthmatic children treated withinhaled steroids. The infection often heals spontaneously (Edwards, 1990).The high incidence of thrush in cancer or AIDS patients should lead a physiciantreating a patient with thrush to test for these diseases (Syrjanen et al., 1988).Another form of mucosal infection is esophageal candidiasis, which may or maynot be an extension of oral thrush. It is particularly frequent in patients receivingtreatment for malignant processes of the hematopoietic or lymphatic system. Themost common symptoms of esophagitis are pain upon swallowing and substernalpain (Edwards, 1990).Gastrointestinal candidiasis follows the esophageal form in frequency among cancerpatients. The small intestine is the third most frequent site of infection. Ulcersare the most common lesions in the stomach and intestine.Mucosal candidiasis recently has been surpassing Trichomonas as a cause of vulvovaginitis.This form is commonly accompanied by vaginal discharge of varyingintensity and pruritus vulvae.Although candidiasis is usually limited to mucocutaneous forms, systemic infectioncan occur through hematogenous transmission, particularly in very weakpatients who are treated with antibiotics over a long period. These cases oftendevelop as a result of lesions caused by medical explorations using catheters, insertionof these instruments in the urethra, or surgical interventions. Though localiza-