Mycology or Fungi Science is the branch of botanic related with the fungi. It is the branch of science which examines the fungi kingdom, their genetic, biochemical and taxonomic features and their use areas.
SKIN MYCOSES (DERMATOPHYTOSIS)
The cause of dermatophytoses is the fungi which infect the superficial keratinized structures (skin, hair, and nail) and do not spread to deeper tissues (Dermatophytes).
The most important Dermatophytes belong to 3 genus;
1. Microsporum: Ectothrix => Hair, skin, rarely nails
2. Trichophyton: Endothrix => They make infections in hair, skin and nails.
3. Epidermophyton: Ectothrix => Skin and nail
Their common feature is to hold the keratinized tissue.
The laboratory diagnosis of dermatophytes are made classically by direct microscopy and culture method. In the studies conducted from various biological samples in our laboratory, most commonly Microsporum canis, Trichophyton mentagrophites, Candida sp. and rarely Trichophyton rubrum were observed.
Microsporum canis: It is the most common cause of the fungi infection seen in cats and dogs and it is the most commonly observed zoophilic infection factor in the world. Isolation rate is generally more than 90%. More commonly Trichophyton mentagrophytes and Microsporum gypseum are also isolated in cats. In the epidemiological studies, these 3 species consist of approximately 98% of the dermatophytes isolated from cats.
Trichophyton mentagrophites: It shows a broad host distribution and it causes infections in cat, dog, horse, rat, rabbit and various other animals. It has cotton, velvety and granular forms. Those variants are common in all over the world.
Candida sp.: It is a yeast species which causes yeast disease in humans and animals and the most important species is Candida albicans. Isolation of this microorganism is unproblematic. It reproduces almost in all mediums in which there is no antifungal. They most easily reproduce in Sabouraud’s agar.
Taking Sample for Mycological Diagnosis
1- Taking Samples for the Superficial Mycosis Factors:
For this purpose, sterile gloves, petri dish or suitable sample taking vessels and scalpel blade are used. The area from which the sample will be taken is cleaned with 70% alcohol and is allowed to air dry for 2-3 minutes. Skin scraping and the area with the lesion is carefully placed into the sterile sample taking vessel with the non-sharp part of the scalpel, by taking minimum hair with the sample. If the samples will be taken from a number of points, the procedure is applied for every point. It is taken care of that the scraping is done without bleeding the area with the lesion. When it is completed, the area with the lesion is cleaned with the suitable skin cleaner.
– Sample can be taken with swabs from moist areas or external auditory canal. Sterile swab is used for the yeasts from earwax, nasal flow and throat swab.
– Throat swab; the sample is taken in the morning (preferably) and with the sterile swab and it is sent to the laboratory. If it will take time to transport to the laboratory, transport medium can be used.
2-Taking sample for internal Mycosis Factor Production:
Body Fluids (Pleura, peritoneum, joint and so on): Samples should be taken into sterile and closed tube or injector and should be sent to the laboratory without waiting. If possible, at least 2 mL sample should be taken.
Blood: Refer to the sample taking for blood culture.
Urine: Refer to the sample taking for urine culture.
Stool: It is transferred to the laboratory in a closed vessel. Since the yeast fungi are found in the intestinal flora of the healthy animals, the production of yeast in the stool is limited.
Blood: Under sterile conditions, blood is taken into the culture medium and transferred to the laboratory. At least two blood cultures should be taken. During blood collection, skin disinfection should be taken care extensively.
Urine: The basic principle of urine taking is obtaining the sample under sterile conditions. The best way to investigate the urinary tract infection is the examination of morning urine or 4-6 hours-waited urine. For female cats and dogs, hand massage if possible, cystocentesis if not possible; for male cats and dogs, natural urine or catheter should be preferred. The first urine is taken to the outside, the middle part is taken into the sterile urine cup until filling the 1/3 of the cup. The last part is thrown out. Urine for culture should be sent to the laboratory within an hour, it must be kept refrigerated if you have to wait.
Stool: It is transferred to the laboratory in the closed vessel. Since the yeast fungi are found in the intestinal flora of the healthy animals, the production of yeast in the stool is limited.