Epidemiological characteristics of Candida species colonizing oral and rectal sites of Jordanian infants

Shireen Y Issa,Asem A Shehabi,Kamal F Akl,Eman F Badran

doi:10.1186/1471-2431-11-79

Abstract

BackgroundThere is evidence that Candida colonization contributes to increasing invasion of candidiasis in hospitalized neonates. Few studies investigated the epidemiology and risk factors of Candida colonization among hospitalized and non-hospitalized infants. This prospective study investigated the major epidemiological characteristics of Candida species colonizing oral and rectal sites of Jordanian infants.MethodsInfants aged one year or less who were examined at the pediatrics outpatient clinic or hospitalized at the Jordan University Hospital, Amman, Jordan, were included in this study. Culture swabs were collected from oral and rectal sites and inoculated on Sabouraud dextrose agar. All Candida isolates were confirmed by the Remel RapID yeast plus system, and further investigated for specific virulence factors and antifungal susceptibility MIC using E-test. Genotyping of C. albicans isolates was determined using random amplified polymorphic DNA (RAPD) analysis method.ResultsA total of 61/492 (12.4%) infants were colonized with Candida species by either their oral/rectal sites or both. Rectal colonization was significantly more detected than oral colonization (64.6% verses 35.4%), particularly among hospitalized infants aged more than one month. The pattern and rates of colonization were as follows: C. albicans was the commonest species isolated from both sites and accounted for 67.1% of all isolates, followed by C.kefyr (11.4%), each C. tropicalis and C. glabrata (8.9%) and C. parapsilosis (3.8%).A various rates of Candida isolates proved to secrete putative virulence factors in vitro; asparatyl proteinase, phospholipase and hemolysin. C. albicans were associated significantly (P < 0.05) with these enzymes than other Candida species. All Candida isolates were susceptible to amphotericin B and caspofungin, whereas 97% of Candida species isolates were susceptible to fluconazole using E-test.The genetic similarity of 53 C. albicans isolates as demonstrated by dendrogram revealed the presence of 29 genotypes, and of these one genotype accounted for 22% of the isolates.ConclusionThis study presents important epidemiological features of Candida colonization of Jordanian infants.

Highlights

There is evidence that Candida colonization contributes to increasing invasion of candidiasis in hospitalized neonates
It is generally observed that most infant candidiasis is thought to be endogenously acquired through prior colonization of different parts of the body, while other studies reported that certain outbreaks of Candida infection were caused by nosocomial infection in neonatal intensive care units [7,8,9,10]
Study participants A total of 492 infants were included in this study over a period of 10-month (20082009) as follows: Group 1; 265 neonates admitted to neonatal intensive care unit (NICU)

Summary

Methods

This prospective study was conducted at the Jordan University Hospital over a period of 10-month; from March 2008 to December 2008. Study participants A total of 492 infants (aged one year or less) were included in this study over a period of 10-month (20082009) as follows: Group 1; 265 neonates admitted to neonatal intensive care unit (NICU). Mycological investigations All growth of yeast-like colonies was subsequently identified by subculture 2-3 representative colonies on a CHROMagar Candida medium (Oxoid, Ltd, Basingstoke, UK) and incubated at 37°C for 24-48 hr. Detection of extracellular production of aspartyl proteinases was made for all Candida isolates by demonstration and measurement of the clear zone of proteolysis around Candida colony growth in bovine serum albumin agar [20]. Production of extracellular phospholipaes activity was estimated by growing Candida on egg-yolk agar and observing the precipitation zone around the Candida colony growth [12]. The differences were considered to be statistically significant if p-value (< 0.05)

Results

Background

Results and Discussion