Etiology of fungaemia and catheter colonisation in Argentinean paediatric patients

Yeast strains obtained from blood cultures and catheters from intensive care units (ICU) and hospitalised oncology paediatrics were studied. Yeast were the first cause of catheter colonisation (51/627), and the third cause of bloodstream infection (44/6065). In catheter, the most frequent species were Candida albicans (34%), C. parapsilosis (27.7%) and C. tropicalis (15%). In blood, C. albicans (40.8%), C. parapsilosis (26.6%), C. tropicalis (15%). Malassezia furfur and Malassezia sympodialis were isolated from catheters from ICU patients. All isolates were susceptible to amphotericin B, 88.8% to itraconazole and 91.9% to fluconazole. Candida albicans and C. tropicalis strains resistant to fluconazole and itraconazol were detected. These results reveal a change in the predominant role of C. albicans as cause of candidemia in hospitalised children and the emergence of antifungal resistant species. These variations emphasise the importance of performing a permanent surveillance to observe and assess them.     

Identification of Candida species isolated from patients in intensive care unit and in vitro susceptibility to fluconazole for a 3-year period

Species level identification of Candida and antifungal susceptibility testing is not generally performed in routine laboratory practice. There is limited information about the distribution of Candida species and antifungal susceptibility in Turkey. In this study, we aimed at identifying Candida isolates to species level from various samples obtained from patients treated in an intensive care unit between 2002 and 2005 and to evaluate fluconazole susceptibilities of the isolates. A total of 320 Candida isolates obtained from 270 patients were identified by conventional methods and using API (Candida and/or 20C AUX) system. Antifungal susceptibility testing was performed by broth microdilution method. Candida albicans was isolated with the highest frequency (65.6%) followed by C. parapsilosis (11.3%), C. glabrata (8.8%) and C. tropicalis (7.8%). Of all the isolates, 92.9% revealed susceptibility to fluconazole. Susceptibility to fluconazole was highest for C. albicans followed by C. parapsilosis and C. glabrata. The MIC(90) values for C. albicans, C. parapsilosis, C. glabrata and C. tropicalis were 1, 2, 8 and 4 mug ml(-1) respectively. Fluconazole remains effective against both C. albicans and the majority of non-albicans Candida species. In this study, we determine the distribution of Candida species and evaluate the susceptibilities of the isolates, particularly for the azoles.     

Anticandidal activity of Pseudomonas aeruginosa strains isolated from clinical specimens

Pseudomonads represent the major group of non-differentiating microorganisms that produce antibiotics. The antibiotic substances produced by this group of organisms are pyocyanin, pyrolnitrin and pseudomonic acid. This study was designed to investigate the in vivo and in vitro anticandidal activity of Pseudomonas aeruginosa strains against Candida species. Forty-four P. aeruginosa strains isolated from various specimens of intensive care patients were included in the study. All P. aeruginosa strains have pyocyanin pigment. Candida albicans ATCC 10231, Candida parapsilosis ATCC 22019, Candida krusei ATCC 6258 and a clinical isolate of Candida tropicalis were used to measure the anticandidal activity of Pseudomonas strains by Kerr's method. The total inhibition rates obtained by using blood agar of C. albicans, C. parapsilosis, C. krusei and C. tropicalis were 41%, 34%, 34% and 25% respectively. When Sabouraud dextrose agar (SDA) was used, the rates were detected as 45%, 39%, 48% and 25% respectively. In the mouse model of concomitant subcutaneous infection with Candida species and P. aeruginosa no yeast were recovered from skin cultures despite 100% detection of P. aeruginosa. Pseudomonas aeruginosa strains isolated from intensive care patients showed anticandidal activity against the Candida species in the present study and this point may be important in the following and treatment of patients.     

Influence of serum on in vitro susceptibility testing of echinocandins for Candida parapsilosis and Candida guilliermondii

Echinocandins are antifungal drugs used for the treatment of invasive candidiasis and aspergillosis. They bind to serum proteins within a rate of 96 to >99%. The effect of serum on in vitro echinocandin susceptibility tests of certain Candida and Aspergillus species was reported. This study was performed to determine the effect of human serum on in vitro susceptibility testing of echinocandins for clinical isolates of Candida parapsilosis and Candida guilliermondii, the species which generally have higher minimum inhibitor concentrations compared with other Candida species. One hundred C. parapsilosis and 20 C. guilliermondii isolates were included in the study. The susceptibility tests of caspofungin, micafungin and anidulafungin were performed using microdilution method, either in the presence or absence of 50% human serum, according to the Clinical and Laboratory Standards Institute (CLSI) M27-A3 guidelines. It was demonstrated that human serum significantly affects the in vitro susceptibility results of echinocandins for C. parapsilosis and C. guilliermondii isolates, mostly yielding an increase in MICs. The most prominent fold changes were for micafungin and anidulafungin in C. parapsilosis, and for anidulafungin in C. guilliermondii isolates. Serum influences the in vitro echinocandin susceptibility in C. parapsilosis and C. guilliermondii. The mechanism and clinical significance of this in vitro change need to be clarified.     

Trends in species causing fungaemia in a tertiary care medical centre over 12 years

Trends in the species of yeast causing fungaemia over a 12-year period at a large tertiary care medical centre were reviewed. A total of 966 unique episodes of fungaemia occurred in 898 patients. There was an overall trend toward fewer fungaemic episodes due to Candida albicans and more due to Candida glabrata and Candida parapsilosis. However, C. albicans remained the predominant species causing fungaemia, and the proportion due to other species varied from year to year. Candida glabrata was disproportionately isolated from older adults, whereas C. parapsilosis was common among neonates and infants. The trends of increasing isolation of C. glabrata and decreasing isolation of C. albicans were associated with increasing usage of fluconazole, but changes in the proportion of fungaemias due to other species appeared to have no association with fluconazole usage.     

Oral yeast carriage in HIV-infected and non-infected populations in Rosario, Argentina

The objectives of the present study were: (i) to assess the frequency of oral colonisation by Candida species in HIV-positive patients and to compare it with a population of HIV-negative individuals, (ii) to determine the prevalence of C. dubliniensis in both populations and (iii) to determine the susceptibility of C. dubliniensis and other Candida species isolated from HIV-positive patients to the most commonly used antifungal agents. Oral samples were obtained from 101 HIV-positive and 108 HIV-negative subjects. For yeast identification, we used morphology in cornmeal agar, the API 20C Aux, growth at 45 °C, d -xylose assimilation, morphology in sunflower seed agar and PCR. The frequency of isolation of Candida in HIV-positive patients was: C. albicans , 60.7%; C. dubliniensis , 20.2%; C. glabrata , 5.6%; C. krusei , 5.6%; C. tropicalis , 4.5%; others, <5%. The frequency of isolation of Candida in HIV-negative patients was: C. albicans , 73.9%; C. tropicalis , 15.5%; C. dubliniensis , 2.1%; C. glabrata , 2.1%; C. parapsilosis , 2.1%; others, <5%. The oral colonisation by yeast in the HIV-positive patients was higher than that in the HIV-negative subjects. The susceptibilities of 42 Candida isolates to three antifungal agents were determined. All isolates of C. dubliniensis were susceptible to fluconazole, although several individuals had been previously treated with this drug. Out of the 42 Candida isolates, 10 presented resistance to fluconazole and 10 to itraconazole. The presence of Candida species, resistant to commonly used antifungal agents, represents a potential risk in immunocompromised patients.     

Microbial profile and drug resistance of Candida strains isolated from the blood of children: an 11-year study

The latest observations indicate a continuous increase in the frequency of fungal infections, particularly in hospital patients, accompanied by changes in both the profile of the isolated strains and their drug susceptibility. The objective of this study was to evaluate the trend in the incidence of candidaemia and susceptibility of antifungal drugs in the Polish Mother's Memorial Hospital over an 11-year period. Blood samples taken from the hospitalised children were sent to the Department of Clinical Microbiology for diagnostic purposes. A total of 195 Candida strains were isolated: 47.7% Candida albicans and 52.3% non- albicans . Candida parapsilosis was isolated in 65.7% of non- albicans strains. The prevalence of Candida spp. decreased from 16.9–20.5% in the years 1996–1997 to 3.1–2.1% in the years 2005–2006. In the years 2000–2005, non- albicans strains were more prevalent. All C. albicans strains were susceptible to amphotericin B, 2.94% of non -C. albicans strains were semisusceptible to amphotericin B, 98.92% of C. albicans and 85.29% of non- albicans strains were susceptible to 5-fluorocytosine. Candida spp. strains are predominant pathogens in fungaemia in children in our hospital. Over the last few years, C. albicans have been replaced by non- albicans strains (predominantly C. parapsilosis ), which exhibit a higher level of drug resistance. The number of Candida spp. isolated from blood decreased during the 11-year study.     

Observational study on candidaemia at a university hospital in southern Italy from 1998 to 2004

In an observational study on candidaemia in hospitalised patients, conducted in a southern Italy hospital during 1998-2004, 155 cases were noted. Candida albicans (CA) was isolated in 71 (45.8%) cases involving mainly patients recovered in ICU, General Surgery and Neonatology. Candida non-albicans (CnA) species were isolated by 84 (54.2%) candidaemic patients, and in particular, Candida parapsilosis was the most frequent species isolated in Pediatric Oncology. 91.6% of the patients had a central venous catheter and only 46.4% were receiving antifungal prophylaxis. Among these patients, 87.5% (63) developed CnA infections; in particular, 41 patients had a C. parapsilosis bloodstream infection. During our study, we observed a variable drift from 1998 to 2003; we registered an evident increment of CnA candidaemia (76.9%) and a decrease of CA cases (23%) only in 2004. The mortality was 26.7%, and we observed that CA was associated with the highest rate of mortality (53.6%). Although Candida infections are correlated primarily with risk factors, their resolution depends on timely diagnosis and early therapy.     

Malassezia and Candida colonisation on glans penis of circumcised men

The Malassezia yeast are members of the normal human cutaneous flora in adults. They also are reported as part of the microflora of the male genital region in mostly uncircumcised males. It has been reported that Malassezia sympodialis and Malassezia globosa are the most frequent yeast belonging to the resident microflora of the penis as in other human skin areas. The aim was to evaluate the prevalence of Malassezia and Candida yeast colonisation on the glans penis of circumcised males. Impression preparations were made on modified Dixon agar. The isolates were identified by morphological and physiological characteristics. A total of 245 circumcised males were included in the study. Of the 245 patients examined, 55 (22.4%) were found to have a mycologically proven yeast fungi on their glans penis. In 17 (30.9%) Malassezia, in 36 (65.5%) Candida, in one (1.8%) Malassezia and Candida, and in one (1.8%) Saccharomyces strains were detected. Malassezia furfur (66.7%) was the most common species among the lipophilic yeast, followed by Malassezia globosa (11.1%), Malassezia obtusa (11.1%) and Malassezia slooffiae (11.1%). Candida albicans was the most common non-lipophilic yeast (46.0%), that was isolated among the other yeast, followed by unidentified Candida strains (18.9%), Candida tropicalis (8.1%), Candida glabrata (8.1%), Candida parapsilosis (8.1%), Candida zeylanoides (5.4%), Candida guilliermondii (2.7%) and Saccharomyces cerevisiae (2.7%). The results of this study showed that Malassezia species were also colonised like Candida on the glans penis of circumcised males.     

Fungal peritonitis in 15 patients on continuous ambulatory peritoneal dialysis (CAPD)

Peritonitis is a frequent complication in patients with chronic renal failure on continuous ambulatory peritoneal dialysis (CAPD) treatment. The aim of this study was to know the prevalence of fungal peritonitis on patients undergoing CAPD, and to determine the antifungal susceptibility pattern of the identified isolates. Samples of the peritoneal dialysis fluid from 165 patients on CAPD treatment with peritonitis manifestations were submitted to mycological study (direct microscopic examination, culture and antifungal susceptibility test). Ten Candida isolates were identified, being C. albicans and C. parapsilosis the most common species. From isolates obtained, three species (C. albicans, C. parapsilosis, and C. guilliermondii) presented itraconazole resistance while C. glabrata was resistant to both itraconazole and ketoconazole. Aspergillus fumigatus was associated to peritonitis in three cases and Acremonium sp. in two.     

Incidence of Yeasts in Pregnant and Non-Pregnant Women in Nigeria: Hefen bei Schwangeren und Nichtschwangeren in Nigeria

The yeast flora of vagina and associated sites (cervix, urethra, perineum and rectum) in 224 pregnant and 106 non-pregnant Nigerian women was investigated. A variety of yeasts represented by 12 species were isolated. Candida albicans was the most frequently isolated species in both groups, accounting for 63.6% of the isolates from pregnant women and 44.8% of the isolates from non-pregnant women. Other species of yeasts infrequently or occasionally encountered were Torulopsis glabrata, C. tropicalis, C. pseudotropicalis, C. parapsilosis, C. krusei, C. guilliermondii, C. stellatoidea, T. candida, T. etchellsii, Saccharomyces cerevisiae, Rhodotorula rubra and Cryptococcus uniguttulatus. C. albicans was also the principal species recovered from symptomatic cases in both groups, followed by T. glabrata in pregnant women and C. parapsilosis in non-pregnant women.     

Oral Candida species and betel quid-associated oral lesions in Padaung women of Northern Thailand

Purpose of the present investigation was to study the association between the betel quid chewing (BQC) habits, the oral yeast flora and oral lesions in female Padaung of northern Thailand. Oral swabs were taken from the tongue and palate of 50 Padaung women with and 50 control individuals without BQC habit. The spectrum of oral Candida species in both groups was determined microbiologically. In addition, oral mucosal lesions were registered in both groups. Mean age of BQ chewers was 35.4 years, of non-chewers was 19.2 years. Candida parapsilosis was the most common Candida spp. isolated both in BQ chewers (46%) and non-chewers (44%). Candida albicans was revealed in 24% of BQ chewers and 18% of non-chewers. There was no significant difference in carriage of Candida spp. isolated between both groups. Forty-four per cent of BQ chewers revealed betel chewers mucosa, 10% showed leukoedema. Isolated populations such as the Padaung may reveal different patterns of candidal flora, in this case a predominance of Candida parapsilosis.     

Azole resistance in neonatal intensive care units in Argentina

The aim of this study was to determine the antifungal susceptibility profile and to detect resistant strains of yeast species isolated from neonates in Intensive Care Units. 92 strains isolated from 25 bloodstream cultures, 20 venous catheters, 23 suprapubic aspirations and 24 rectal swabs were studied. A Candida glabrata strain resistant to fluconazole was detected. Candida krusei appeared with its inherent resistance to fluconazole and showed cross-resistance to itraconazole. Two Candida albicans strains were resistant to azoles, one to itraconazole and the other to fluconazole with a high minimum inhibitory concentration (MIC) for itraconazole. All Candida tropicalis strains were susceptible to fluconazole but two of them showed resistance to itraconazole. The detection of resistant strains in neonates whom had not received previous antifungal therapy is noteworthy. The variations in the epidemiology of fungal infections observed and the antifungal resistance detected emphasize the importance of performing a regular surveillance to observe and to assess them.     

Nosocomial bloodstream infections associated with Candida species in a Turkish University Hospital

In recent years, a progressive increase in the frequency of nosocomial candidaemia has been observed, especially among the critically ill or immunocompromised patients. The aim of this study was to evaluate the trend in incidence of candidaemia together with potential risk factors in an 850-bed Turkish Tertiary Care Hospital in a 4-year period. A total of 104 candidaemia episodes were identified in 104 patients. The overall incidence was 0.56 per 1000 hospital admissions and the increase in incidence of candidaemia from 2000 to 2003 was found to be statistically significant (P = 0.010). Candida albicans was the most common species (57.7%) and non-albicans species accounted for 42.3% of all episodes. The most common non-albicans Candida sp. isolated was C. tropicalis (20.2%) followed by C. parapsilosis (12.5%). The most frequent risk factors possibly associated with the candidaemia were previous antibiotic treatment (76.9%), presence of central venous catheter (71.2%) and total parenteral nutrition (55.8%). Our results show the fact that the incidence of candidaemia caused by non-albicans species is frequent and increasing significantly, although the most common isolated Candida species were C. albicans and further investigations are necessary to evaluate the mechanisms of increasing incidence of candidaemia caused by non-albicans species.     

Fungaemia in hospitalized patients

Summary. At various clinics of IRCCS S. Matteo Hospital, Pavia, Italy, 269 blood cultures recovered from immunocompromised patients over 4 years have been examined mycologically. Of the 269 cultures, 101 were from HIV-infected patients and five were from cardiac transplant recipients. Of the total examined 96 blood cultures were positive (36%).
The most frequent genus was Candida: C. albicans (48%), C. tropicalis and C. parapsilosis (8% each), C. glabrata and C. guillermondii (3% each). Cryptococcus neoformans was detected in 21 patients (22%).
Zusammenfassung. Im Vierjahreszeitraum von 1991–1994 wurden 269 Blutkulturen von abwehrgeschwächten Patienten verschiedener Abteilungen der Poliklinik S. Matteo, Pavia, Italien, mykologisch untersucht. Davon kamen 101 Blutkulturen von HIV-positiven Patienten und fünf von Herztransplantierten. Insgesamt waren 96 Blutkulturen (36%) positiv. Candida albicans wurde zu 48%, C. tropicalis und C. parapsilosis zu je 8%, C. glabrata und C. guilliermondii zu je 3% und Cryptococcus neoformans zu 22% isoliert.     

The frequency of Candida parapsilosis in onychomycosis. An epidemiological survey in Israel

Candida albicans is regarded as the major pathogen in yeast-induced onychomycosis. Based on our impression of an increasing prevalence of Candida parapsilosis in this disease, we examined the data of two mycology laboratories in the same geographic location, from 1994 to 1996 in one (centre A) and for 1995 (6 months) in the other (centre B). A total of 954 and 230 toenails and 621 and 190 fingernails, respectively, underwent KOH microscopy and culture studies in each centre. Positive findings were noted in 45 and 65% of the toenails and 44 and 72% of the fingernails, respectively. In the toenails, Candida spp. were found in 22 and 15%, respectively, and in the fingernails, in 77 and 63%, respectively. The most frequent Candida species was C. parapsilosis (39.5% in toenails, 36.7% in fingernails), followed by C. albicans (19.5% in toenails, and 34.4% in fingernails). These results demonstrate a higher frequency of isolation of C. parapsilosis compared with C. albicans in onychomycosis. This might have important therapeutic implications.     

Fluconazole and itraconazole susceptibilities of Candida spp. isolated from oropharyngeal specimens and blood cultures of paediatric haematology/oncology patients

This study examined the in vitro susceptibilities to fluconazole and itraconazole of isolates of Candida spp. from surveillance oropharyngeal specimens and blood cultures from paediatric patients with malignancy. The species distribution of 100 isolates from oropharyngeal specimens was C. albicans 86%, C. glabrata 7%, C. lusitaniae 4%, C. parapsilosis 2% and C. tropicalis 1%. From a total of nine isolates from blood cultures the species distribution was C. albicans 33.3%, C. parapsilosis 33.3 % and C. guilliermondii 33.3%. Only three of the oropharyngeal isolates were resistant to fluconazole (MIC > or = 64 mg l(-1)) and only two were resistant to itraconazole (MIC > or = 1 mg l(-1)). None of the blood culture isolates was resistant to either agent. At this centre, C. albicans is the predominant species from oropharyngeal specimens, but non-albicans Candida species predominate in blood cultures. Although resistance to fluconazole and itraconazole is rare at present, continued surveillance is warranted to monitor trends in species distribution and antifungal susceptibility.     

Incidence and Distribution of Vaginal Yeasts in Malaysian Women: Häufigkeit und Verteilung vaginaler Hefen bei malaysischen Frauen

A total of 2,153 high vaginal swabs were processed for the presence of yeasts. The specimens were obtained from pregnant and non-pregnant Malaysian women with and without vaginitis. The yeast species most commonly isolated were Candida albicans, C. glabrata, C. famata and C. parapsilosis. C. albicans was isolated from 27% of pregnant women with vaginitis, 14% of pregnant women with no overt vaginitis, 15% of non-pregnant women with vaginitis, and 3% of non-pregnant women with no vaginitis. The significant difference of the isolation rates from women with and without vaginitis indicates that C. albicans is likely to be a vaginal pathogen.     

In vitro susceptibility of 545 isolates of Candida spp. to four antifungal agents

Summary. The in vitro susceptibility to amphotericin B, fluconazole, itraconazole and ketoconazole of 545 Candida strains from patients treated at the University Hospital of the Canaries was determined by means of a microdilution test. The distribution of the species was as follows: Candida albicans (342), Candida tropicalis (70), Candida glabrata (68), Candida parapsilosis (65). Of Candida albicans isolates, 8.5% and 7.6% showed resistance to itraconazole and fluconazole respectively. Of C. tropicalis isolates 34.3%, 27.1% and 2.9% were resistant to itraconazole, fluconazole and ketaconazole respectively. For C. glabrata , 10.3% and 4.4% of the isolates under study demonstrated resistance to fluconazole and itraconazole respectively. Only 4.6% and 1.5% of C. parapsilosis isolates demonstrated resistance to fluconazole and itraconazole respectively. C. tropicalis was the most resistant strain and C. parapsilosis the most sensitive. The greatest percentages of resistance in vitro were seen with the triazoles.
Zusammenfassung. Es wurde die Empfindlichkeit von 545 Candida -Stämmen für Amphotericin B, Fluconazol, Itraconazol und Ketoconazol in vitro in einem Mikrodilutionstest bestimmt. Bei den Stämmen handelte es sich um Isolate von Patienten, die in der Universitäts-Klinik der Kanarischen Inseln behandelt worden waren. Das Untersuchungsgut war wie folgt verteilt: 342 Candida albicans , 70 C. tropicalis , 68 C. glabrata , 65 C. parapsilosis. Bei C. albicans waren 8.5% gegen Itraconazol und 7.6% gegen Fluconazol resistent. Bei C. tropicalis wurden 34.3% resistent gegenüber Itraconazol befundet, 27.1% gegen Fluconazol und 2.9% gegen Ketoconazol. Bei C. glabrata waren 10.3% resistent gegen Fluconazol und 4.4% gegen Itraconazol. Candida parapsilosis wurde zu 4.6% gegen Fluconazol und zu 1.5% gegen Itraconazol als resistent befundet. Somit erwies sich C. tropicalis als die resistenteste und C. parapsilosis als die sensibelste Art.