Sevim Akcaglar

Environmental distribution of Cryptococcus neoformans and C. gattii around the Mediterranean basin

In order to elucidate the distribution of Cryptococcus neoformans and C. gattii in the Mediterranean basin, an extensive environmental survey was carried out during 2012-2015. A total of 302 sites located in 12 countries were sampled, 6436 samples from 3765 trees were collected and 5% of trees were found to be colonized by cryptococcal yeasts. Cryptococcus neoformans was isolated from 177 trees and C. gattii from 13. Cryptococcus neoformans colonized 27% of Ceratonia, 10% of Olea, Platanus and Prunus trees and a lower percentage of other tree genera. The 13 C. gattii isolates were collected from five Eucalyptus, four Ceratonia, two Pinus and two Olea trees. Cryptococcus neoformans was distributed all around the Mediterranean basin, whereas C. gattii was isolated in Greece, Southern Italy and Spain, in agreement with previous findings from both clinical and environmental sources. Among C. neoformans isolates, VNI was the prevalent molecular type but VNII, VNIV and VNIII hybrid strains were also isolated. With the exception of a single VGIV isolate, all C. gattii isolates were VGI. The results confirmed the presence of both Cryptococcus species in the Mediterranean environment, and showed that both carob and olive trees represent an important niche for these yeasts.

An investigation of Candida species isolated from blood cultures during 17 years in a university hospital

Candidemia is the most frequent manifestation observed with invasive candidiasis. The aim of this study was to analyse the trends of candidemia in a large tertiary‐care hospital to determine the overall incidence during January 1996–December 2012, as well as to determine the susceptibility of 453 isolates according to the revised Clinical and Laboratory Standards Institute (CLSI) breakpoints. Candidemia episodes in adult and paediatric patients were retrospectively analysed from the laboratory data of Uludağ University Healthcare and Research Hospital. The 17‐year period studied was divided into three periods (1996–2001, 2002–2007 and 2008–2012) for better comparison, and candidemia incidence was determined by the ratio of total number of patients with candidemia per 1000 patients admitted to the hospital and per 10 000 patient days in these three periods. Redefined CLSI M27‐A3 breakpoints were used for interpretation of antifungal susceptibility results. Candidemia incidence was determined as 2.2, 1.7 and 1.5 per 1000 admitted patients during 1996–2001, 2002–2007 and 2008–2012 respectively. A significantly decreased candidemia incidence was obtained in the third period. C. albicans (43.8%) was the most common candidemia agent, followed by C.parapsilosis (26.5%) in all three periods. According to the revised CLSI breakpoints, there was fluconazole resistance in C. albicans, C.parapsilosis, C.tropicalis and C.glabrata species (1.4%, 18.2%, 2.6% and 14.3% respectively). Almost all Candida species were found susceptible to voriconazole except one C.glabrata (7.1%) isolate. Candidemia is an important health problem. Local epidemiological data are determinative in the choice of appropriate antifungal treatment agents.

Multilocus sequence typing analysis reveals that Cryptococcus neoformans var. neoformans is a recombinant population

Cryptococcus neoformans var. neoformans (serotype D) represents about 30% of the clinical isolates in Europe and is present less frequently in the other continents. It is the prevalent etiological agent in primary cutaneous cryptococcosis as well as in cryptococcal skin lesions of disseminated cryptococcosis. Very little is known about the genotypic diversity of this Cryptococcus subtype. The aim of this study was to investigate the genotypic diversity among a set of clinical and environmental C. neoformans var. neoformans isolates and to evaluate the relationship between genotypes, geographical origin and clinical manifestations. A total of 83 globally collected C. neoformans var. neoformans isolates from Italy, Germany, France, Belgium, Denmark, Greece, Turkey, Thailand, Japan, Colombia, and the USA, recovered from different sources (primary and secondary cutaneous cryptococcosis, disseminated cryptococcosis, the environment, and animals), were included in the study. All isolates were confirmed to belong to genotype VNIV by molecular typing and they were further investigated by MLST analysis. Maximum likelihood phylogenetic as well as network analysis strongly suggested the existence of a recombinant rather than a clonal population structure. Geographical origin and source of isolation were not correlated with a specific MLST genotype. The comparison with a set of outgroup C. neoformans var. grubii isolates provided clear evidence that the two varieties have different population structures.

A comparative study of dermatophyte infections in Bursa, Turkey

A total of 555 specimens from 372 patients with symptoms compatible with superficial mycosis were included in this study. Those from patients clinically diagnosed as having dermatomycosis were thoroughly investigated by mycological examinations in the laboratory, including microscopic studies of KOH mounts and cultivation of the samples in culture. The results of this study and a previous study in our hospital conducted in 1980 were compared with respect to clinical presentation and etiological agents. Onychomycosis was the most common clinical form of dermatomycoses, and Trichophyton rubrum was the most common pathogen in this study.

Two cases of cryptococcal meningitis in immunocompromised patients not infected with HIV

We present the cases of two patients with cryptococcal meningitis who were predisposed to fungal infection because of diabetes mellitus (Case 1) and systemic lupus erythematosus (Case 2). Both patients were tested negative for anti‐HIV antibodies.

Fundamental niche prediction of the pathogenic yeasts cryptococcus neoformans and cryptococcus gattii in europe

Fundamental niche prediction of Cryptococcus neoformans and Cryptococcus gattii in Europe is an important tool to understand where these pathogenic yeasts have a high probability to survive in the environment and therefore to identify the areas with high risk of infection. In this study, occurrence data for C. neoformans and C. gattii were compared by MaxEnt software with several bioclimatic conditions as well as with soil characteristics and land use. The results showed that C. gattii distribution can be predicted with high probability along the Mediterranean coast. The analysis of variables showed that its distribution is limited by low temperatures during the coldest season, and by heavy precipitations in the driest season. C. neoformans var. grubii is able to colonize the same areas of C. gattii but is more tolerant to cold winter temperatures and summer precipitations. In contrast, the C. neoformans var. neoformans map was completely different. The best conditions for its survival were displayed in sub-continental areas and not along the Mediterranean coasts. In conclusion, we produced for the first time detailed prediction maps of the species and varieties of the C. neoformans and C. gattii species complex in Europe and Mediterranean area.

Persistence of candiduria in ICU catheterized patients is not linked to adherence and proteolytic activities of Candida strains.

ObjectiveIn this study, the patients who developed asymptomatic candiduria in the intensive care unit were followed prospectively for the persistence of candiduria after the replacement of indwelling urethral catheter and the correlation between persistence and virulence factors (proteinase enzyme activity and epithelial adhesion) was assessed.DesignProspective study.SettingIntensive care unit and mycology laboratory at a university hospital.PatientsThirty-four patients with asymptomatic candiduria were included in the study.ResultsCandiduria persisted in 19 of 34 patients(56%; group 1) and cleared in 15 of 34 patients(44%; group 2) after urinary catheters were changed. When the virulence factors (epithelial adhesion and proteinase activity) and distribution of Candida spp. were compared between two groups, no statistically significant correlation was found.ConclusionThe host immune response might be more important than virulence factors of Candida spp. for persistence of candiduria.

Effects of Malassezia yeasts on serum Th1 and Th2 cytokines in patients with guttate psoriasis

Background  Systemic and focal infections caused by microorganisms have been known to induce or exacerbate psoriasis. Although the role of yeast species of the genus Malassezia in the pathogenesis of psoriasis is not fully understood, it is thought that these lipophilic yeasts may represent a triggering factor in the exacerbation of psoriatic lesions.

Environmental distribution of Cryptococcus neoformans and Cryptococcus gattii around the Mediterranean basin

In order to elucidate the distribution of Cryptococcus neoformans and C. gattii in the Mediterranean basin, an extensive environmental survey was carried out during 2012-2015. A total of 302 sites located in 12 countries were sampled, 6436 samples from 3765 trees were collected and 5% of trees were found to be colonized by cryptococcal yeasts. Cryptococcus neoformans was isolated from 177 trees and C. gattii from 13. Cryptococcus neoformans colonized 27% of Ceratonia, 10% of Olea, Platanus and Prunus trees and a lower percentage of other tree genera. The 13 C. gattii isolates were collected from five Eucalyptus, four Ceratonia, two Pinus and two Olea trees. Cryptococcus neoformans was distributed all around the Mediterranean basin, whereas C. gattii was isolated in Greece, Southern Italy and Spain, in agreement with previous findings from both clinical and environmental sources. Among C. neoformans isolates, VNI was the prevalent molecular type but VNII, VNIV and VNIII hybrid strains were also isolated. With the exception of a single VGIV isolate, all C. gattii isolates were VGI. The results confirmed the presence of both Cryptococcus species in the Mediterranean environment, and showed that both carob and olive trees represent an important niche for these yeasts.

Multiple intracranial abscesses due to Cryptococcus neoformans: an unusual clinical feature in an immunocompetent patient and a short review of reported cases

We present a case of multiple intracranial abscesses caused by Cryptococcus neoformans in a patient who presented with no symptoms of immunodeficiency.