Mustafa Altay Atalay

Investigation of possible virulence factors in Candida strains isolated from blood cultures

BACKGROUND The Candida species, which are one of the most common causes of nosocomial bloodstream infections, present with high mortality and morbidity rates. This study aims to investigate the production of esterase, phospholipase, proteinase, and biofilm formation ability of the Candida strains isolated from the blood cultures. MATERIALS AND METHODS Between June 2011 and July 2012, the Candida strains, which were isolated from blood cultures of a total of 50 patients, were studied. The esterase activity was analyzed in the Tween-80 agar, while phospholipase activity was studied in the egg yolk agar. The proteinase activity and biofilm formation were identified by using the petri dish method and microplate method, respectively. RESULTS Of 50 specimens obtained from individual patients, 17 (34%) were identified as C. albicans, 14 (28%) as C. glabrata, 9 (18%) as C. parapsilosis, 5 (10%) as C. krusei, 4 (8%) as C. kefyr, and 1 (2%) as C. tropicalis. The rate of proteinase, phospholipase, and esterase positivity was higher in the C. albicans isolates. Biofilm formation was the highest in the C. parapsilosis strains. CONCLUSIONS Higher rate of virulence factors in the most commonly isolated Candida species than other species indicates that these virulence factors play a crucial role in the pathogenesis.

Tenckhoff catheter obstruction without peritonitis caused by Curvularia species

Peritonitis remains the most common complication of peritoneal dialysis (PD). Staphylococci are responsible for the majority of all PD-related peritonitis episodes (Piraino B et al., Perit Dial Int 2005; 25: 107–31). While fungal peritonitis is relatively uncommon, Candida albicans accounts for the majority of fungal peritonitis episodes (Wang AY et al., Am J Kidney Dis 2000; 36: 1183–92). Fungal peritonitis caused by Curvularia species is extremely rare and has been reported in only a few cases (Pimentel JD et al., J Clin Microbiol 2005; 43: 4288–92; Ujhelyi MR et al., Rev Infect Dis 1990; 12: 621–7). Herein we report a case with continuous ambulatory peritoneal dialysis (CAPD) catheter obstruction caused by Curvularia species in the absence of any signs or symptoms of peritonitis.

Saprochaete capitata as an emerging fungus among patients with haematological malignencies

Saprochaete capitata is a very rare pathogen that causes invasive disease particularly in patients with haematological malignancies. We recognised a clustering of S. capitata fungaemia in recent years. So, we report our 6‐year surveillance study of fungaemia among patients with haematological malignancies and haematopoietic stem cell transplant. We performed a retrospective and observational study. Hospitalised patients aged >18 years with haematological malignancies were included in the study. A total of 51 fungaemia episodes of 47 patients were analysed. The characteristics of fungaemia in patients with S. capitata compared to patients with candidemia. Median duration of neutropenia was 21.5 days in patients with S. capitata fungaemia, whereas this duration was significantly shorter in patients with candidemia (8 days). Interval between first and last positive culture was significantly longer in patients with S. capitata fungaemia (P < 0.05). Previous use of caspofungin was significantly more common in patients with S. capitata fungaemia. Thirty‐day mortality was found 40% for patients with candidemia, whereas it was 39% for patients with S. capitata. In conclusion, despite its limitations this study showed that a novel and more resistant yeast‐like pathogen become prevalent due to use of caspofungin in patients with long‐lasting neutropenia which was the most noteworthy finding of this 6‐year surveillance study.

Antifungal Activity of Olive Oil and Ozonated Olive Oil Against Candida Spp. and Saprochaete Spp.

ABSTRACT Ozonated olive oil was investigated for their capacity to inhibit growth of 38 yeast strains of Candida albicans, Candida glabrata, Candida krusei, Candida parapsilosis, and Saprochaete capitata. Two different ozonated olive oil (OZO1, OZO2) and two different olive oil (OL1, OL2) samples having different biochemical parameters were assessed in terms of their antifungal ability and comparison was made. Fluconazole was chosen as control antifungal agent. Each sample’s antifungal activity decreased in the following order: OZO1 > OZO2 > OL1 ≥ OL2. This study demonstrated that ozonated olive oil may help to control some fluconazole-resistant and dose-dependent sensitive fungal strains.

Üçüncü basamak bir hastanedeki gastroenteritli çocuklarda Rotavirüs enfeksiyonu sıklığı

Objective: Rotavirus was shown to be the most important agents of viral gastroenteritis in infants and young children, responsible for the majority of hospitalizations for this illness within the first two years of life. The aim of this study was to investigate the frequency of rotavirus antigen positivity in pediatric patients with acute gastroenteritis admitted to Erciyes University Hospital and to evaluate the distribution according to the age of the patients, and seasons of the year. Methods: The records of stool specimens of a total of 2636 patients between the ages of 0-16 admitted to our hospital between January 2009 and December 2012 due to acute gastroenteritis were investigated retrospectively. Rotavirus antigens were searched in the fresh stool specimens by immunochromatographic test.

Large unstained cells are correlated with inflammatory biomarkers in patients with invasive aspergillosis

Abstract Objective: The percentage of large unstained cells (%LUCs) reflects peroxidase-negative cells and activated lymphocytes. Unlike other infections, the value of %LUCs in the diagnosis of fungal infections is not clear. We aimed to evaluate %LUCs and its correlations with other inflammatory parameters of invasive aspergillosis (IA) patients. Methods: Twenty patients and 20 healthy participants were included. Full blood count parameters including %LUCs values were recorded. Platelet to lymphocyte ratio (PLR), neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), eosinophil to lymphocyte ratio (ELR) were calculated. Results: There was a significant difference between the study groups for %LUCs [2.40 (2.22–3.25); 1.43 (1.25–2.10), respectively; p<0.001]. Furthermore, %LUCs were statistically significantly correlated with PLR, NLR and MLR (p=0.020, 0.040, 0.040; respectively) but not correlated with ELR (p>0.05). Conclusion: The %LUCs values were significantly increased and correlated with markers of inflammation in patients. We suggest that the %LUCs is a useful predictor and may be an aid in the diagnosis and/or the management of IA and may help clinicians for follow up these patients in therapy process. Our study provides target pathways for further studies in the diagnosis of Aspergillus-infected patients using inflammatory parameters.

Cutaneous ulcerations caused by Paecilomyces variotii in a renal transplant recipient

Skin infections caused by Paecilomyces species have been rarely described in patients with solid organ transplantation. Cutaneous manifestations are highly variable and include erythematous macules, nodules, pustules, and vesicular and necrotic lesions. The diagnosis of these infections is generally made by examination of a skin biopsy. Management of these fungal infections is difficult due to the immunocompromised state of the patients. Moreover, antifungal therapy and immunosuppressive drug interactions should be considered during treatment management. Herein, we reported a case of cellulitis caused by Paecilomyces variotii in a 56‐year‐old man who had undergone a kidney transplantation. Erythematous macular and nodular lesions on the left hand and left foot appeared first; within 2 months the skin lesions became ulcerated, hemorrhagic, and progressively painful and the patient was admitted to our hospital. The diagnosis was made by skin biopsy and tissue culture. The skin lesions resolved by the sixth week of the treatment with voriconazole.

Can serums be replaced by Mueller-Hinton agar in germ tube test?

Background: The germ tube test (GTT) is inexpensive, easy, and well-defined test that differentiates Candida albicans (excluding Candida dubliniensis and Candida africana) from other species. The aim of this study was to evaluate various serums (i.e., human, rabbit, horse, and fetal bovine serum) used in the GTT and Mueller-Hinton agar (MHA). Materials and Methods: Fifty species isolated from various clinical samples that were defined as C. albicans by both conventional and DNA sequence analysis methods were included in the study. One to two colonies of C. albicans were mixed into 0.5–1 ml of fetal bovine serum, horse serum, rabbit serum, and human serum. Serums and MHA were incubated at 37°C for GTT. They were removed from the incubator and evaluated after 30 min, 1 h, 2 h, and 3 h of incubation. The GTT was accepted to be positive only if germ tube was 1/2 the width and 3 times the length of the parent yeast cell and with no constriction at the point of origin. Results: When the use of serums and MHA for GTT was statistically evaluated, according to the positive scoring, the best results were obtained with MHA and with rabbit, horse, and fetal bovine serum, respectively. The best definition over time statistically was the third hour. Conclusion: It is suggested that inexpensive MHA is a fast, appropriate, and reliable medium for the probable diagnosis of GTT and C. albicans; however, additional studies are still needed to define other Candida species.

Identification and molecular epidemiology of dermatophyte isolates by repetitive‐sequence‐PCR‐based DNA fingerprinting using the DiversiLab system in Turkey

Dermatophyte species, isolation and identification in clinical samples are still difficult and take a long time. The identification and molecular epidemiology of dermatophytes commonly isolated in a clinical laboratory in Turkey by repetitive sequence‐based PCR (rep‐PCR) were assessed by comparing the results with those of reference identification. A total of 44 dermatophytes isolated from various clinical specimens of 20 patients with superficial mycoses in Kayseri and 24 patients in Hatay were studied. The identification of dermatophyte isolates was based on the reference identification and rep‐PCR using the DiversiLab System (BioMerieux). The genotyping of dermatophyte isolates from different patients was determined by rep‐PCR. In the identification of dermatophyte isolates, agreement between rep‐PCR and conventional methods was 87.8 % ( 36 of 41). The dermatophyte strains belonged to four clones (A ‐D) which were determined by the use of rep‐PCR. The dermatophyte strains in Clone B, D showed identical patterns with respect to the region. In conclusion, rep‐PCR appears to be useful for evaluation of the identification and clonal relationships between Trichophyton rubrum species complex and Trichophyton mentagrophytes species complex isolates. The similarity and diversity of these isolates may be assessed according to different regions by rep‐PCR.

Are Commercial Systems Used for the Identification of Yeasts Enough Alone?: A Case Report

Infections developing due to Trichosporon species especially in immunosuppressed patients have started to increase also in our country as well as in the world. Some difficulties have been encountered in identification and treatment of Trichosporon spp. which are relatively more resistant to antifungal treatment. Accurate and rapid identification of yeast species is very important to ensure determination of the appropriate antifungal agent in treating these infections. Due to long time span and intense effort required, determination using conventional methods has recently been replaced by common use of commercial systems allowing rapid identification. However, the commercial systems used to determine yeasts are reported to have higher correct identification rates for frequently isolated species, whereas lower rates for rarer species. In this report, we aimed to address that the commercial systems are enough alone for identification by evaluating a case of urinary tract infection with a positive urine culture yielding yeasts. A urine culture revealed dry, wrinkled, waxy, pink, yeast-like colonies on blood agar and eosin-methylene blue agar after a 24-hour incubation. These colonies were identified as Cryptococcus sp. using VITEK® 2 (bioMérieux, Marcy l’Etoile, France) system. On the other hand, this isolate had been demonstrated as Trichosporon asahii by microscopic and macroscopic appearance, carbohydrate assimilation test results and urease positivity. Additionally, antifungal susceptibility of isolate was determined using microdilution (amphotericin B, voriconazole, fluconazole) and Etest® (AB Biodisk, Solna, Sweden) methods (caspofungin, anidulafungin) according to Clinical Laboratory Standards Institute M27-A3 standard. In conclusion, this case report demonstrated that there is a need for confirmation of results with conventional methods for determination of rare species such as Trichosporon spp. identified with commercial systems based on biochemical properties, and antifungal susceptibility tests should be performed in clinical microbiology laboratories. Klimik Dergisi 2016; 29(2): 95-8.