Mikrobiyoloji bulteni最新文献

This study was aimed to identify the most frequently observed pathogens in uncomplicated urinary tract infections from outpatient urinary isolates obtained across seven different geographical regions in Türkiye and to determine whether the antibiotic resistance rates of these pathogens differ significantly between these regions. The study included patients aged 18 to 65 years who were diagnosed with uncomplicated urinary tract infections and had positive urine cultures from March 2021 to August 2022, across 37 different centers in Türkiye. The participating centers were selected based on their use of the disk diffusion method, in line with the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines, to ensure standardization of urine culture data. A total of 1850 patients who met the inclusion criteria were included in the study. The analysis of the distribution of antibiotic resistance rates in Escherichia coli isolates revealed statistically significant differences in resistance to ampicillin, fosfomycin and nitrofurantoin across different regions (p< 0.05, p< 0.05, p< 0.05, respectively). The Southeastern Anatolia region was identified as having the highest resistance rates to fosfomycin and trimethoprim-sulfamethoxazole (27.4% and 35.3%, respectively). Additionally, the region with the highest nitrofurantoin resistance was determined as the Eastern Anatolia Region with a rate of 35.7% and the region with the highest ciprofloxacin resistance was determined as the Central Anatolia Region with a rate of 51%. Our study demonstrated that antibiotic resistance in the treatment of uncomplicated urinary tract infections varies by geographical region. We believe this comprehensive, national prospective study will provide valuable insights for clinicians planning empirical treatment for uncomplicated urinary tract infections.

Brucellosis is a zoonotic disease that causes high rates of morbidity and mortality due to difficulties in diagnosis and inadequate treatment. The purpose of this study was to assess the diagnostic significance of presepsin, trigger receptor expressed on soluble myeloid cells-1 (sTREM-1), and interferon-gamma (IFN-gamma) levels in patients with brucellosis. One hundred twenty-one brucellosis patients aged 18 or over and 39 healthy volunteers were included in this prospective study. The cases were classified as either acute, subacute or chronic according to the duration of symptoms. Serum was separated from blood samples taken from all groups and presepsin, sTREM-1, and IFN-gamma levels were determined before treatment. Serum presepsin, sTREM-1, and IFN-gamma levels were all significantly elevated in patients with Brucellosis compared to the control group (p< 0.05). Serum presepsin and sTREM-1 levels were also significantly higher in patients with acute brucellosis compared to the subacute and chronic groups (p< 0.05). The lowest serum IFN-gamma levels were observed in the chronic Brucellosis group. Significant moderately strong, positive correlations were determined between presepsin and sTREM-1 and IFN-gamma values (r= 0.695, r= 0.769, p< 0.001). Significant low-level positive correlations were observed between presepsin and AST, BUN and CRP (r= 0.215, r= 0.214, and r= 0.279, respectively p< 0.05). Higher serum presepsin levels were determined in patients with positive blood cultures than in those with no blood culture growth (p< 0.05). At a threshold value of 469.43 pg/mL, the presepsin test exhibited 95% sensitivity and 89% specificity in differentiating cases of Brucellosis from the healthy group. At a threshold value of 27.14 pg/mL, the sTREM-1 test exhibited 93% sensitivity and 84% specificity in differentiating Brucellosis cases from the healthy control group. Serum presepsin, sTREM-1 and IFN-gamma levels may be helpful in distinguishing patients with Brucellosis from healthy individuals and in differentiating between acute, subacute, and chronic Brucellosis.

The aim of this study was to investigate the frequency of sasX, arginine catabolic mobile element (ACME) genes, biofilm formation and some biofilm related virulence factor genes in causative and contaminant coagulase negative staphylococci (CNS) strains isolated from blood cultures. Of the 150 CNS strains included in the study, 50 were grouped as infectious agents and 100 as contaminants. Biofilm formation of the strains was investigated by microplate method and the presence of sasX, ACME, mecA and biofilm associated virulence factor genes icaA, icaD, aap, bhp and IS256 were investigated by inhouse polymerase chain reaction method. While 52% of the strains in the infectious agents group and 57% of the strains in the contamination group phenotypically formed biofilm; when the levels of biofilm positivity were compared, it was observed that the strains in the infectious agents group (30%) formed biofilm at a stronger level than the strains in the contamination group (14%) (p= 0.027). Biofilm-associated icaA, icaD, IS256, aap and bhp genes were found positive in 33%, 45%, 43%, 74% and 6% of the strains in the contamination group and 64%, 62%, 64%, 74% and 8% of the strains in the infectious agents group, respectively. ACME gene regions arcA, kdpA and opp3B and sasX related gene region were found positive in 30%, 7%, 8% and 14% of the strains in the contamination group and in 12%, 2%, 6% and 10% of the strains in the infectious agents group, respectively. The positivity of icaA, icaD and IS256 genes alone or together in the infectious agents group (p< 0.001, p= 0.050, p= 0.015, respectively) and the positivity of ACME and arcA in the contamination group (p= 0.008, p= 0.015, respectively) were statistically significantly higher. No significant difference was found between the two groups for sasX, aap and bhp genes. In conclusion, among the CNS strains isolated from blood cultures, strains that form a strong biofilm and are positive for biofilm-associated gene regions alone or together can be considered as infectious agents, while strains that are found to be arcA positive in the absence of clinical signs of infection can be considered as contaminants.

Central nervous system infections (CNS) are life-threatening infections in children, requiring urgent intervention and rapid diagnosis. In this study, we aimed to investigate the efficacy of syndromic tests in diagnosing CNS infections and the distribution of viral pathogens in pediatric patients. A total of 145 pediatric patients with a prediagnosis of CNS infection based on clinical findings by a pediatric infectious disease specialist were included in the study. Microscopic examination, biochemical tests, bacteriologic culture, and syndromic test (BioFire® FilmArray® Meningitis/Encephalitis Panel) were performed on cerebrospinal fluid samples obtained from the patients. Nearly half (44.8%) of the patients were younger than one year of age, the median age was 12 months (6-60 months), and the male-to-female ratio was 1.7, with 92 male and 53 female patients. Viral pathogens were observed in most of the 29 (18.8%) patients with syndromic test positivity (n= 23, 79.4%), while bacterial pathogens were detected in 20.6% (n= 6). No fungal pathogens were detected. Bacterial pathogens were Streptococcus pneumoniae [3.4% (5/145)] and Neisseria meningitidis [0.7% (1/145)]. Viruses were enterovirus [6.9% (10/145)], human herpesvirus-6 [5.5% (8/145)], herpes simplex virus type 1 [1.4% (2/145)], cytomegalovirus [0.7% (1/145)], human parechovirus [0.7% (1/145)], varicella zoster virus [0.7% (1/145)]. The main finding in cases with positive syndromic test was fever (n= 19, 65.5%), followed by vomiting (n= 15, 51.7%), convulsion (n= 14, 48.3%) and rash (n= 6, 20.6%). For turnaround time the median was 111 minutes and the mean was 119 minutes. Despite the lack of a performance study including sensitivity and specificity for syndromic testing or alternative tests for viral etiology, our study demonstrates the benefits of syndromic testing in children with presumed CNS infections, such as shortening the diagnostic period and guiding empirical treatment. It also constitutes an affirmative example of laboratory and clinical collaboration.

According to the World Health Organization (WHO), leishmaniasis is a zoonotic/anthroponotic parasitic disease endemic in 99 countries. It is estimated that approximately 12 million people are infected with Leishmania spp. and 350 million people live at risk. Every year, two million new cases are added to these figures. One and a half million cases of zoonotic/anthroponotic cutaneous leishmaniasis and 500 000 cases of visceral leishmaniasis are reported annually. One person is estimated to to be infected with cutaneous leishmaniasis in every 20 seconds and visceral leishmaniasis causes 60 000 deaths. In this report, two pediatric cases diagnosed with visceral leishmaniasis were presented. In the study, bone marrow aspirations were performed to determine the etiology of the disease in an eight-month-old male patient with fever and hepatosplenomegaly who had been followed up in Manisa Celal Bayar University, Department of Pediatrics, Division of Pediatric Hematology with the diagnosis of severe glucose-6-phosphate dehydrogenase (G-6PD) deficiency since the neonatal period and in a nine-month-old female patient who had had a high fever and bicytopenia for two weeks. Bone marrow aspirations were cultured in NNN medium and their smears were stained and examined with Giemsa. rk-39 and Leishmania IFAT tests were performed by using patients' sera. Quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) analysis was also performed for Leishmania spp. Leishmania spp. amastigotes were observed in Giemsa-stained smear preparations, Leishmania spp. promastigotes were grown in NNN medium, rk39 rapid diagnostic kit was weakly positive, Leishmania IFAT was positive at a titer of 1/1024 and Leishmania tropica was identified as the causative agent by RT-qPCR analysis for both cases. These two cases suggested that fatal cases of visceral leishmaniasis may increase with the spread of visceralized isolates of L.tropica, the most common causative agent of cutaneous leishmaniasis in Türkiye, and this issue may create a significant public health problem.