Influence of the hospital environment on yeast colonization in nursing students

Distribution of genetically characterized yeasts and its antifungals susceptibility in the hospital environment

Candida spp. is one of the main pathogens associated with nosocomial infection in Brazil and worldwide. The aim of this study was to evaluate the distribution of Candida yeasts in the ICU and their susceptibility to the antifungal agents terbinafine and fluconazole. The samples were collected by swabbing nine surfaces in the ICU of a hospital located in Pelotas, RS. These isolates were genetically characterized by sequencing the internal transcript spacer (ITS) using the primers ITS1 and ITS4. The test against antifungals was performed by Microdilution in Broth (CLSI-M27-A4). 64 yeasts identified as Candida parapsilosis (45.31%; n = 29), Meyerozyma (Pichia) guilliermondii (28.12%; n = 18), Claviceps lusitaneae (25%; n = 16) and Candida tropicalis (1, 56%; n = 1) mostly at the counter used for handling medicines and food distribution (68.75%; n = 44). Susceptibility to antifungals varied between species. These results describe potentially pathogenic Candida species as contaminants in the ICU environment. The study environment is a potential source of exogenous infection for hospitalized patients.

An evaluation of the hand and nasal flora of Turkish nursing students after clinical practice

AIM

The purpose of this study was to evaluate and compare the hand and nasal flora of nursing students before and after the clinical practice.

BACKGROUND

Hospitals are places where infective agents abound. Healthcare workers, relatives of patients and students practising in the hospital medium are often exposed to these infective agents. Although the role of the hand and nasal flora of healthcare workers in the development of nosocomial infections has been emphasised by earlier studies, there are a limited number of studies which investigate the hand and nasal flora of nursing students.

DESIGN

Descriptive.

METHODS

This descriptive study involved 66 volunteer nursing students. Two samples of flora from both hands and nose of each student were obtained. The inoculated samples were then evaluated through routine bacteriological study methods. Chi-square and percentage calculations were used in comparisons.

RESULTS

None of the students had methicillin-resistant Staphylococcus aureus or methicillin-resistant coagulase-negative Staphylococcus colonisation in the hand samples before clinical practice, 6.1% of the students had methicillin-resistant Staphylococcus aureus and 4.5% had methicillin-resistant coagulase-negative Staphylococcus colonisation after the practice. Although the differences between the rates of contamination with pathogen micro-organisms in the hand and nasal flora of the student nurses before and after clinical practice were not significant, the rate of colonisation after clinical practice was higher.

CONCLUSIONS

In this study, the rate of colonisation after clinical practice was higher. These findings indicate that students might have been contaminated with bacteria during clinical practice.

RELEVANCE TO CLINICAL PRACTICE

The results of this study have practical importance in clinical practice. The role of the hand and nasal flora of nursing students in the development of nosocomial infections is significant. For this reason, some precautions, such as using gloves and handwashing with special solutions when needed, should be taken to prevent nosocomial infections and protect students against associated risks.

[Nasal fungal microbiota in allergic and healthy subjects]

Environmental fungi, moulds and yeasts could reach the nasal cavity with the inhaled air causing respiratory symptoms in atopic subjects, but little is known about the fungal flora of this site. In the present study samples of the nasal cavities of 135 subjects aged 18-35 years (48 allergic patients to fungi, mites and/or cat fur and from 87 normal subjects--healthy, control group) were cultured. All of them lived in the metropolitan area of Barcelona. Fungi were isolated from 41.5% of healthy people and in 14.8% of allergy patients (p = 0.011). Morphologically, 50.4% of the isolates were located within 4 genera: Cladosporium, Penicillium, Aspergillus and Alternaria, fungi which are considered the most allergenic. The most prevalent species were: Cladosporium herbarum and C. cladosporioides (23.6%). Alternaria alternata was isolated only in 8.8% of samples from the allergic group, although most subjects were sensitive to this species. There were not differences in the isolation rate between genera and smoking-no-smoking groups. The lower prevalence of nasal fungi from allergic patients could be related to the nasal insufficiency, the hypersecretion and the larger use of handkerchiefs.

Microbial colonization of the hands of residents

To determine whether carriage of resistant Gram-positive organisms by residents increases over time, the dominant hand of pediatric residents was cultured. Among first-year residents, 53 Gram-positive organisms were isolated; 12 were resistant to oxacillin, 13 to clindamycin. Six residents had organisms resistant to both; 14 carried at least one resistant to either. Among third-year residents, 46 Gram-positive organisms were cultured; 9 were resistant to oxacillin, 6 to clindamycin. Three residents carried organisms resistant to both; 10 carried at least one resistant to either. Colonization with resistant Gram-positive organisms did not increase with length of training.

Predictive value of oral colonization by Candida yeasts for the onset of a nosocomial infection in elderly hospitalized patients

The incidence of nosocomial yeast infections has increased markedly in recent decades, especially among the elderly. The present study was therefore initiated not only to determine the predictive value of oral colonization by yeasts for the onset of a nosocomial Candida infection in elderly hospitalized patients (>65 years), but also to clarify the factors that promote infection and to establish a relationship between the intensity of oral carriage and the onset of yeast infection. During this prospective cohort study, 256 patients (156 women and 100 men with a mean age of 83±8 years) were surveyed for yeast colonization or infection. Samples were collected every 4 days from day 0 to day 16 from four sites in the mouth, and intrinsic and extrinsic factors that might promote infection were recorded for each patient. Pulsed field gel electrophoresis was performed on Candida albicans isolates from all infected patients. Poor nutritional status was observed in 81 % of the patients and hyposalivation in 41 %. The colonization level was 67 % on day 0 (59 % C. albicans) and a heavy carriage of yeasts (>50 c.f.u.) was observed for 51 % of the patients. The incidence of nosocomial colonization reached 6·9 % on day 4 (6·1 % on day 8 and 2·7 % on day 12), and that of nosocomial infection was 3·7 % on day 4 (6·8 % on day 8, 11·3 % on day 12 and 19·2 % on day 16). Of the 35 patients infected, 57 % were suffering from oral candidiasis. The principal risk factors for colonization were a dental prosthesis, poor oral hygiene and the use of antibiotics. The risk factors for infection, in addition to those already mentioned for colonization, were endocrine disease, poor nutritional status, prolonged hospitalization and high colony counts. Genotyping revealed person-to-person transmission in two patients. Thus, this study demonstrates a significant association between oral colonization and the onset of yeast infections in elderly hospitalized patients. Therefore, oral samples should be collected at admission and antifungal treatment should be administered in cases of colonization, especially in patients presenting a heavy carriage of yeasts. Genotyping of the strains confirmed the possibility of person-to-person transmission.

Emergence of resistant staphylococci on the hands of new graduate nurses

OBJECTIVE

To describe the aerobic microbial flora on the hands of experienced and new graduate nurses over time.

DESIGN

A prospective cohort design that examined the relationship between duration of employment in an intensive care unit (ICU) and the microbial flora on the hands of experienced and new graduate nurses during a 23-month period.

SETTING

A 50-bed, level III-IV neonatal ICU in New York City.

PARTICIPANTS

Twelve experienced nurses and 9 new graduate nurses working full time in the NICU.

INTERVENTION

One hundred fifty samples were obtained from the clean, dominant hands of the nurses. Cultures were performed at baseline and then quarterly for each experienced and new graduate nurse. Baseline and final cultures of Staphylococcus epidermidis were further examined using pulsed-field gel electrophoresis.

RESULTS

At baseline, a significantly larger proportion of the experienced nurses had methicillin-resistant, coagulase-negative staphylococci isolated from their hands compared with the new graduate nurses (95% and 33%, respectively; P = .0004). For a second culture, performed 1 to 4 months later, there were no longer significant differences between the two groups (82% and 54%, respectively; P = .12). By the last culture, all staphylococcal isolates were methicillin resistant in both groups of nurses; 3 were methicillin-resistant S. aureus.

CONCLUSIONS

Colonization with methicillin-resistant staphylococci occurred after brief exposure to the hospital environment, despite the use of antiseptic hand hygiene agents. Furthermore, at final culture, the two groups shared one dominant hospital-acquired strain of S. epidermidis.

Prevalence and Fluconazole Susceptibility ofCandidaSpecies Recovered From the Oropharynx of Healthcare Workers (HCWs) and Non-HCWs

We compared oropharyngeal cultures and fluconazole susceptibility forCandidain 100 healthcare workers (HCWs) and 100 non-HCWs. Isolates were identified using standard microbiological methods. Susceptibility was determined by Etest and microliter method. There was no significant difference in prevalence or species of oropharyngealCandidabetween HCWs and non-HCWs. Fluconazole resistance was infrequent.