Introduction observed at the ends of life. At present, its incidence is increasing.

1. Introduction observed at the ends of life. At present, its incidence is increasing.

In recent years, there has been an increase in the Thrush is characterized by the appearance of a development of fungal infections in the oral cavity of creamy white stippling or yellowing of the mouth immuno-compromised patients [1, 2]. Among the (gums, tongue, oral mucosa or corners), which is causative organisms, we can include Aspergillus, slightly over-large, and can cause pain. When the Mucormycosis , Rhizopus, Cryptococcus and other (all condition is more intense, instead of dotted there are observed at low frequencies), but undoubtedly the large white patches on the tongue and the rest of the most common genus is Candida. In mucosa of the mouth, the rub is eliminated or plates immuno-competent people but not an increase in the and stippling are superficial wounds that bleed slightly number of frames fungal disease, an increase in the

[3-5].

colonization of these opportunistic fungi has been Organisms causing this disease belong to the genus observed. Candida, which consists of yeasts ovoid 2-6 m wide Candidiasis is a cosmopolitan disease of great × 3-9 m long, are Gram positive, and that after 48 h importance and one of the most frequent fungal of culture in Sabouraud media as added or no infections in the oral cavity. It affects both sexes antibiotic (chloramphenicol or gentamycin), colonies equally and has no preference of age, except the one of 4 to 5 mm in diameter, smooth, glossy or matt

white color. Cultivation alone will inform us of the Corresponding author: Floridia Ricardo, biochemist,

laboratory assistant, research fields: parasitology and mycology. existence of yeast, but not differentiate colonization E-mail: [email protected].

Determination of Fungal Colonization in the Oral Cavity of College Students

from infection, so the observation of a direct drugs, hormones) that sweep the protective examination is essential. If the same individualize a

microorganisms away and allow the opportunistic pseudomycelia (C. glabrata does not pseudomycelia)

pathogens to proliferate. The third group of factors is and inflammatory cells we will suggest an infection, if

dependent Candida, given its ability to adhere to the blastospores are seen going to suggest a settlement.

cells of the mouth or dentures, to evade host defenses, The culture allows the isolation of the fungus for

secrete enzymes such as proteases, phospholipases antifungal susceptibility testing, and thereby applies a

and the ability to compete with other microorganisms proper therapy on the patient to prevent the selection

for nutrients [9, 10].

of resistant strains. The genus Candida is comprised of The transformation from commensal to pathogen more than 200 species, but this condition only reverts

takes to convert morphogenetic organism in the yeast importance as follows: C. albicans, C. tropicalis, C.

phase of the filament. At this late stage, it activates the krusei , C. glabrata, C. guillermondi and C.

pathogenic mechanisms of this fungus that causes the parapsilosis . The most important is C. albicans that is

breakdown of balance between health and isolated by more than 80% of cases; C. tropicalis and

disease [11, 12].

C. glabrata by 10% and the rest are rarely isolated. Other elements that allow the host defense of the Species of the genus Candida are pathogenic in

proliferation of pathogens in the oral cavity are the nature, as diners are part of the ancillary or

patient’s saliva. It constitutes a primary antifungal supplementary oral microbiota and imbalances need to

because it has the function of mechanical sweeping occur both in the patient’s immune system and in the

and protein components such as lysozyme, lactoferrin, protective flora present in the tissue, to colonize,

lactoperoxidase, glycoproteins and a pH between 5.6 infect and cause disease. Within the oral cavity of

and 7.8 that hinder the adhesion and growth of the Candida species are the most location on the tongue

fungus. Anti-yeast are also immersed in the same oral but they can also live in gums, mucosal wall of the

cavity, they are mostly of secretory IgA and act by mouth and palate. They have a great capacity for

recognizing epitopes on the surface of the fungus, adhesion to both host cells, as inert materials

thereby inhibiting the adhesion thereof to the oral (prosthesis).

mucosa, and enabling phagocytosis by PMNs that Estimated 30% to 50% of healthy people have this

possess receptors Fc portion of these antibodies [13, 14]. fungus as part of their normal oral microbiota [6-9].

It is described in the bibliography that patients with The transformation from commensal to pathogen

oral candidiasis show increased levels of secretory depends on the interaction and modification of three

IgA in saliva, but Candida can produce proteases that groups of factors. The first factor is the one that

destroy the antibodies. The determination of IgA in involves the host, in which alterations of the mucosal

saliva will inform us whether the immunological barrier, either by maceration, trauma, oral hyperplasia,

capacity of the patient’s oral mucosa is normal or epithelial dysplasia and occlusion predispose to

insufficient [15, 16].

candidiasis, or immune disease (HIV), neoplasms, deficiency anemia, stress, depression and

2. Materials and Methods

physiological changes (pregnancy). The second factor

2.1 Study Area

is the one that involves changes in the microenvironment of the oral cavity, whose protective commensal flora is

Fifty samples were collected for mycological study affected by the use of drugs (antibiotics, in oral cavity, from students in the course of immunosuppressants, antineoplastics, psychotropic Parasitology and Mycology, Faculty of Chemistry,

Determination of Fungal Colonization in the Oral Cavity of College Students

Biochemistry and Pharmacy, Universidad Nacional de

5 mL of Chloramphenicol Succinate (Quemicetina of San Luis, with an average age of 24 in the participants.

Rontag) to achieve a final concentration of 250 mg/L Before developing the work, a briefing was made on it,

of the antibiotic in the finished agar. Subsequently, a and the ones who agreed to participate expressed their

second swab from the same areas was conducted and, willingness to do so by informed consent, which were

with this swab, a mark was prepared on a microscope given full details of the work (Ordinance No. 005/08

slide and then it was coloured by Giemsa staining [17]. UNSL).

2.4 Methods Used

2.2 Use of the Survey The Petri dishes were cultured in an oven at 28 °C

Participants were given a survey to assess issues for 15 days, those in which no growth was observed related to conditions affecting the immune system,

in that period of time were reported as negative; on either as the taking of medication (corticosteroids,

the contrary, those presenting colonies were tested to antibiotics, oral contraceptives, etc.), underlying

be typed. First, there was a Giemsa stain of diseases (diabetes, anemia, etc.) and alterations that

microorganisms that formed the colony, and then had previously been suffered in the mouth (thrush,

rang in a differential medium (Candida, Paris France) herpes, gingivitis, bleeding, and others). This survey

that allowed the offense; those who could not be also assessed oral hygiene, which was classified into

identified are evaluated by Api Candida four groups: performed after each meal, twice daily,

(BioMerieux).

once daily and unrealized. It was inquired if the In the saliva sample, we came to the participant had the smoking habit, considering determination of the concentration of secretory IgA

smoking people to those who consumed at least one by radial immunodiffusion according to Mancini cigarette in the month that preceded the study, and

technique. Procedure was used for RID finally if the mentioned participant was completing a

plates-PLATE by placing 5 L of the saliva sample pregnancy period. This survey detailed the current oral

into each well. The diffusion time was 72 h, after cavity lesions observed during sampling (Appendix A).

the stipulated time was over; we measured the halo

2.3 Collection of Samples of precipitation which correlated with the concentration of antibody.

The sample collection was conducted in the All the data was entered in an Excel 2000

Laboratory of Parasitology of the University. At first, spreadsheet program and processed with it.

the participant was offered a clean container to collect the saliva sample for assay of secretory IgA.

3. Results

Subsequently, he was given water to rinse the mouth,

3.1 Obtained Positive Results

and to make appropriate swabs. Cotton swabs were used, with which toured areas of the oral cavity are

Of the 50 samples that were evaluated, from more likely to be colonized by yeast according to the

immuno-competent university students, the growth of bibliography consulted. Samples were taken from the

at least one yeast colony was observed in nine of them surface of gums, palate, tongue and inner walls of the

(Fig. 1). After being typified finds that seven were oral cavity. The swab was immediately sown in Petri

yeasts of Candida albicans species and the remaining dishes in an agar prepared for this purpose. The

two Saccharomyces cerevisiae (Figs. 3-5). culture agar used was Sabouraud dextrose agar

Regarding the survey data, the following results (Britain) that, once prepared and sterilized, was added

were obtained.

Determination of Fungal Colonization in the Oral Cavity of College Students

Negative41

C. albicans 7

Saccharomices cerevisae

Fig. 1 Positivity of the samples studied.

Fig. 2 Positive cultures according to sex.

26 All Participants

24 C. albicans

20 S. cerevisiae

Corticoteroids

Antibióticts

Anticonceptives

Levothiroxine Withous Medication

Fig. 3 Participants according to crops exposed to medication.

Determination of Fungal Colonization in the Oral Cavity of College Students

Smoking 1 11%