CD39 expression on immune cells predicts methotrexate response in rheumatoid arthritis patients.

Background/aim: Rheumatoid arthritis (RA) is a chronic inflammatory disease affecting mostly small joints, such as hand and foot joints symmetrically with irreversible joint destruction. In this study, the relationship between CD39 expression and the treatment response of RA patients was examined to investigate its potential as a biomarker that demonstrates treatment response. Materials and methods: This study included 77 RA patients and 40 healthy controls (HC). The RA patients were divided into 2 groups based on their response to RA treatment, those with a good response to methotrexate (MTX) monotherapy and those with an inadequate response based on the American College of Rheumatology and the European League Against Rheumatism response criteria. Various immunological parameters and Disease Activity Score in 28 Joints (DAS28) were examined between the groups using the Student's t-test. Results: The monocytic myeloid-derived suppressor cell (M-MDSC) percentage was higher in the RA patient group versus the HC group. The CD39 expression in the T lymphocytes were higher in patients that responded well to the MTX compared to those showing inadequate response. Additionally, s negative correlation was found between the DAS28 and CD39 in the T cells. Conclusion: The results showed that the improvement in treatment response to the therapy in RA patients could be because of the enhancement in the CD39/adenosine (ADO) pathway. Therefore, therapies targeting the CD39/ADO pathway in T cells may improve RA treatments.

Experience with enterococcal meningitis/ventriculitis in children.

BACKGROUND: Enterococcal infections are increasingly common in hospitalized patients. Enterococcal meningitis/ventriculitis (EMV) is an extremely rare condition of enterococcal infections, occurring particularly in children. This study investigated the clinical and microbiological characteristics, predisposing factors, and prognosis in pediatric patients with EMV. METHODS: Pediatric patients (<18 years) diagnosed with EMV were retrospectively evaluated over 10 years. RESULTS: The study included a total of 25 isolates from 24 patients, median age 23 months (range: 1-136 months). The most common symptoms included vomiting, fever, and headache, with hydrocephalus shunt and preterm birth being the two most common conditions. Commonly associated infections, with central nervous system (CNS) devices as a predisposing factor, were due to external ventricular drainage and ventriculoperitoneal shunts. Two patients with spontaneous meningitis were preterm infant. Of the isolates, 44% were Enterococcus faecalis, 44% E. faecium, and 12% E. gallinarum. Five (20%) isolates were vancomycin resistant. Twelve patients were resistant to anti-enterococcal antibiotics, including ampicillin, ciprofloxacin, imipenem, teicoplanin, gentamicin, and linezolid (40%, 20%, 8%, 8%, 4%, and 4%, respectively). Enterococcus faecium was more resistant to ampicillin, ciprofloxacin, teicoplanin, and vancomycin than E. faecalis. The median treatment duration was 17 days (interquartile range: 14-26 days).The mortality rate was 8.3% (2/24; both associated with vancomycin resistance). CONCLUSIONS: Neurosurgical conditions are the most common predisposing factors for EMV. Preterm birth is an important predisposing factor in children. Because EMV is nonspecific in clinical findings, it should be considered when there is an underlying CNS disorder and empirical treatment should begin in this direction.

[Humoral Immune Response in Inactivated SARS-CoV-2 Vaccine: When Should a Booster Dose be Administered?] / Inaktif SARS-CoV-2 Asisi Humoral Immün Yanit: Rapel Doz Ne Zaman Uygulanmalidir?

Vaccination induces the development of long-lasting immunity necessary for a sustained and essential protective antibody response. Understanding how long the humoral immune response induced by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) inactivated vaccine lasts is important to create an effective immunization scheme. This study aimed to detect the first, third, sixth month concentrations and seroconversion rates of the antibodies induced by the inactivated vaccine. The study included 282 healthcare workers who were vaccinated at days 0 and 28 by the inactivated SARS-CoV-2 vaccine (3 µg/0.5ml). Anti-S-RBD-IgG (receptor binding domain) antibody concentrations and seroconversion rates were examined in vaccinated healthcare workers at the first, third and sixth months after the vaccination. MAGLUMI SARS-CoV-2 S-RBD IgG (CLIA) (Snibe Diagnostics, Chinese) kit was used for the detection of antibodies. The mean age of the healthcare workers was 38.93 ± 10.59 (min= 21-max= 64). After the administration of the second vaccine dose, the participants were found to be reactive for anti-SRBD-IgG antibodies by 98.2% and 97.8% at the first and third months, respectively,. The decrease in the mean plasma concentrations of anti-S-RBD IgG was observed as 56.7% in the cohort with only two doses of the vaccine (first month: 42.4 AU/ml versus third month: 18.2 AU/ml). In the cohort with a history of coronavirus disease 2019 (COVID-19) prior to the vaccination, the decrease was observed as 25.1% (first month: 58.29 versus third month: 43.64 AU/ml) and at a mean of 57.4 (0-90) days prior to vaccination, the decrease rate was 43.1% (first month: 55.05 AU/ml versus third month: 31.28 AU/ml), keeping more stable in participants infected at a mean of 183.1 (91-330) days prior to vaccination(a decrease of 5.2%; with 62.34 AU/ml at first and 59.08 AU/ml at third months). At the end of the sixth month, antibodies could not be detected in 16.7% of people who (n= 42) received two doses of the inactivated vaccine, and the amount of anti-S-RDB IgG decreased by an average of 52.5% compared to the third month, and by 74.8% compared to the first month. Antibody concentrations at the first, third, and sixth months after the vaccination with two doses of the inactivated SARS-CoV-2 vaccine were found to be decreased and at the sixth month, the rate of non-reactive people was 16.7%. As participants who had COVID-19 at a mean of 181 (90-330) days before the vaccination presented with a more stable antibody level, it can be concluded that a booster at months 6-12, resulting in a schedule of 0-1-6 months, is recommended for the inactive SARS-CoV-2 vaccination for effective herd immunity.

SARS-COV-2 vaccine: first-month results of a six-month follow-up study.

BACKGROUND: Various COVID-19 vaccines are being developed around the world. Important questions to be answered regarding vaccines are efficacy, safety, and whether antibodies are protective when used in different communities. This study aimed to determine seroconversion rates of the inactivated SARS-CoV-2 vaccine in healthcare workers in a hospital and short-term adverse events due to the vaccine. METHODS: The study carried out in Çukurova University, Turkey, comprised of 282 healthcare workers who received two doses of the inactivated SARS-CoV-2 vaccine administered in two 3 µg doses, 28 days apart. On day 28, after the second dose, antiS-RBD IgG and total anti-spike and anti-nucleocapsid IgM and IgG antibodies against SARS-CoV-2 were detected by using in vitro chemiluminescence immunoassay method. RESULTS: The mean age of participants was 39.06±10.65 (min=21, max=65) with 43.6% males and 56.4% females. On day 28, after the second dose, the seroconversion rates were found to be 92.9% for total anti-spike and anti-nucleocapsid IgG and 15.2% for IgM and 98.2% for anti-S-RBD IgG antibodies and having natural COVID-19 prior to vaccination, age and comorbidity were found to be significant factors for immunogenicity. The incidence of at least one adverse event was found as 29.8% after the first dose and 24.1% after the second dose, with the most common adverse events of having pain at the injection site, weakness, fatigue, and headache.

[Comparison of Candida Polymerase Chain Reaction Method and Blood Culture in Patients with High Risk of Candidemia in Intensive Care Unit]. / Yogun Bakim Ünitesinde Takip Edilen Kandidemi Riski Yüksek Hastalarda Candida Polimeraz Zincir Reaksiyonu Yöntemi ve Kan Kültürünün Karsilastirilmasi.

Candida species are responsible for 70-90% of invasive fungal infections in the intensive care unit. Early diagnosis and treatment is important in candidemia. Improper diagnosis and treatment increases mortality and morbidity significantly. Because of the late results of blood cultures and low sensitivity of the serological tests when used alone, molecular methods should be investigated in this field. In this study, the results of the Candida real-time polymerase chain reaction (Rt-PCR) test, which was studied from blood culture and whole blood, were compared in patients with high candidemia risk who were followed in the General Surgery Intensive Care and Anesthesiology and Reanimation Unit of Cukurova University Faculty of Medicine. It was aimed to investigate the practical utility of Candida RT-PCR test, which is a rapid diagnosis method in patients with suspected candidemia. In our study, 90 patients with high risk of candidemia according to the criteria determined according to the guidelines were evaluated prospectively. Urine, perineum, axilla, tracheal aspirate culture and two sets of blood cultures were obtained from the patients. Blood sample was also drawn into an ethylenediaminetetraacetic acid (EDTA) tube and stored at -40°C for later Candida Rt-PCR study. In Candida Rt- PCR, species-specific primers were used to distinguish species. Candida score (CS) of the patients was calculated. Forty one (45.5%) of the patients were female and 49 (55.5%) were male. The median age of the patients was 61.5 years. Candida was positive in blood culture in three (3.3%) of the patients included in the study, while Candida Rt-PCR was positive in 17 (18.9%). Candida species detected in the blood culture and Rt-PCR test were compatible with each other. Rt-PCR was significantly more positive (p= 0.006). Candida Rt-PCR positivity was significantly higher in patients receiving total parenteral nutrition (p= 0.028), malignancy (p= 0.021), and history of surgery in the last three months (p=0.003). The difference in CS between patients with PCR positive and PCR negative was statistically significant (p= 0.015). Our study was conducted in a high-risk population for candidemia and the results of Candida Rt-PCR was found to be more positive than blood culture. Rt-PCR positivity and blood culture positivity were associated with high CS. In the light of these data, it was thought that it would be appropriate to use molecular methods in the diagnosis and support them with CS, especially in patients with high risk of candidemia. Considering that blood culture, which is the gold standard for the diagnosis of candidemia, gives late results and is 50% positive, using faster diagnostic methods for candidemia is important to reduce mortality and morbidity. The fast and good results of Candida PCR method have shown that it can be used in diagnosis. However, lack of standardization of primers used in PCR tests may cause false positives. Additional studies are needed in this respect.

Clinical aspects and prognosis of polymicrobial keratitis caused by different microbial combinations: a retrospective comparative case study.

PURPOSE: The purpose of this study is to compare the predisposing factors, clinical findings, treatment results, and prognosis for polymicrobial keratitis. METHODS: In this retrospective comparative case study, we identified the cases of polymicrobial keratitis from the microbiological records (n = 649) at Balcali Hospital, Çukurova University (Adana, Turkey; October 2010-2018). We included all the cases of infectious keratitis with two different types of microbial agents and grouped them as follows: group 1 (n = 25), bacterium-fungus coexistence; group 2 (n = 12), herpes simplex virus (HSV) or Acanthamoeba with bacterial infection; and group 3 (n = 7), HSV or Acanthamoeba with fungal infection. We compared the clinical and microbiological characteristics, and treatment outcomes among the groups. RESULTS: In our study, we found that 44 infectious keratitis cases (6.7%) were of polymicrobial nature. The mean follow-up period was 11.4 ± 17.8 months. In total, 17 different bacteria along with 3 different fungi, HSV, and Acanthamoeba were isolated. The most common bacterium was Staphylococcus epidermidis (25%). Most of the fungal pathogens were filamentous. Patients with initial treatment failure and requiring surgical intervention had larger infiltrates (p = 0.023, p = 0.003, respectively) than other patients. Older age was associated with delayed recovery and poor visual prognosis. CONCLUSIONS: Bacterial-fungus coexistence is the most common combination among patients, but other combinations should also be considered for suspected polymicrobial etiology. The corneal infiltrate size may be an important indicator of the course of disease and response to treatment. A closer and longer follow-up period should be planned for older patients.

Importance of 14-3-3eta, anti-CarP, and anti-Sa in the diagnosis of seronegative rheumatoid arthritis

Background/aim: Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial inflammation. The study aimed to assess serum 14-3-3eta, anti-CarP, and anti-Sa in seronegative RA (SNRA) patients who were treatment-naïve as well as in healthy subjects. This is the first study in the literature to examine these autoantibodies together in SNRA patients. Materials and methods: Forty-five treatment-naïve SNRA patients and 45 healthy subjects were recruited. Drugs change the levels of autoantibodies; therefore, patients who took any medication had been excluded from our study. Anti-carbamylated protein, anti-Sa, and 14-3-3eta were measured by using three different ELISA kits. Results: Median serum concentration of healthy controls in 14-3-3eta was 0.02 (0.02­0.27) ng/mL. Median serum concentration of SNRA patients in 14-3-3eta was 1.00 (0.48­1.28) ng/mL. Data were analyzed with Mann­Whitney U tests; the P-value was <0.001 in 14-3-3eta. Receiver operating characteristic (ROC) curve analysis showed that 14-3-3eta in SNR compared to healthy controls had a significant (P < 0.001) area under the curve (AUC) of 0.90 (95% confidence interval, 0.83­0.96). At a cutoff of ≥0.33 ng/mL, the ROC curve yielded a sensitivity of 88.9%, a specificity of 82.2%, a positive predictive value of 83.3%, and a negative predictive value of 88.1%. Conclusion: We found that 14-3-3eta can be used as a diagnostic marker in SNRA.

Lean six sigma methodologies improve clinical laboratory efficiency and reduce turnaround times.

BACKGROUND: Organizing work flow is a major task of laboratory management. Recently, clinical laboratories have started to adopt methodologies such as Lean Six Sigma and some successful implementations have been reported. This study used Lean Six Sigma to simplify the laboratory work process and decrease the turnaround time by eliminating non-value-adding steps. METHODS: The five-stage Six Sigma system known as define, measure, analyze, improve, and control (DMAIC) is used to identify and solve problems. The laboratory turnaround time for individual tests, total delay time in the sample reception area, and percentage of steps involving risks of medical errors and biological hazards in the overall process are measured. RESULTS: The pre-analytical process in the reception area was improved by eliminating 3 h and 22.5 min of non-value-adding work. Turnaround time also improved for stat samples from 68 to 59 min after applying Lean. Steps prone to medical errors and posing potential biological hazards to receptionists were reduced from 30% to 3%. CONCLUSION: Successful implementation of Lean Six Sigma significantly improved all of the selected performance metrics. This quality-improvement methodology has the potential to significantly improve clinical laboratories.

Performance comparison of new generation HCV core antigen test versus HCV RNA test in management of hepatitis C virus infection.

The study has evaluated the performance of HCV core antigen (Cag) test by comparing HCV RNA PCR assay which is considered the gold standard for management of HCV infection. Totally, 132 samples sent for HCV RNA (real-time PCR) test were included in the study. Anti-HCV antibody test and HCV Cag test were performed by chemiluminescent enzyme immunoassay (CMEI). Anti-HCV test was positive in all samples. HCV RNA was detected in 112/132 (84.8%) samples, and HCV Cag in 105/132 (79.5%). The most common HCV genotype was genotype 1 (86%). Considering the HCV RNA test as gold standard; the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of Cag test were found to be 93.75%, 100%, 100%, 74.07% and 94.69%, respectively, and paired test results were detected as highly concordant. A high level of correlation was seen between HCV RNA and Cag tests, however, the concordance between the two tests appeared to be disrupted at viral loads lower than 103IU/mL. On the contrary, the correlation reached significance for the values higher than 103IU/mL. Viral loads were in the 17-2500IU/mL range for the negative results for Cag test. Pearson's correlation coefficient revealed a considerably high correlation. The concordance between HCV RNA and Cag tests was disrupted under a viral load lower than 103IU/mL. Therefore, it would be appropriate to consider cost effectiveness, advantages and limitations of the HCV RNA and Cag tests during the decision on which method to use for patient management.

Biological Variation and Reference Change Value Data for Serum Neuron-Specific Enolase in a Turkish Population.

BACKGROUND: Neuron-specific enolase (NSE) is a recognized biomarker for the assessment of cerebral injury in neurological disorders. This study aims to report a definitive assessment of the biological variation (BV) components of this biomarker, including within-subject BV (CVI), between-subject BV (CVG), index of individuality (II), and reference change value (RCV), in a cohort of Turkish participants using an experimental protocol. METHODS: Six blood specimens were collected from each of the 13 apparently healthy volunteers (seven women, six men; ranging in age from 23 to 36) on the same day, every 2 weeks for 2 months. Serum specimens were stored at -20°C until analysis. Neuron-specific enolase levels were evaluated in serum samples using an electrochemiluminescence (ECLIA) immunoassay kit with a Roche Cobas e 411 auto-analyser. ANOVA test was used to calculate the variations. RESULTS: The CVI and CVG for NSE were 21.5% and 28.8%, respectively. Analytical variation (CVA) was calculated as 10.2%. Additionally, II and RCV were calculated as 0.74 and 66% (95% confident interval, CI), respectively. CONCLUSION: As the performance index (PI) was found to be less than 2 (PI = 0.95), it is concluded that the NSE measurements have a desirable performance for analytical imprecision. Since the II was found to be less than 1 (II: 0.74), the reference values will be of little use. Thus, RCV would provide better information for deciding whether a significant change has occurred.

Hepatitis B, Hepatitis C, Human immunodeficiency virus and syphilis frequency among blood donors: A single center study.

We aimed to provide updated results for seroprevalence of hepatitis B, hepatitis C viruses while presenting first data for human immunodeficiency virus and syphilis seropositivity amongst blood donors in Adana, Turkey. Screening and confirmatory test results of 62,461 donors were evaluated. HBsAg, anti-HCV, anti-HIV1/2 and syphilis seropositivity was 1.92%, 0.48%, 0.20%, 0.18% respectively, based on screening tests, and 1.66%, 0.05%, 0.003%, 0.10% respectively, according to confirmatory tests. Transfusion-transmitted infections (TTI) was more prevalent in low-educated donors. HBsAg and syphilis seropositivity rates were higher in married subjects. We found that the prevalence of HBV and HCV was significantly decreased in the last two decades in Adana. Importantly, this study provides first data in HIV and syphilis seropositivity rates among blood donors in our region and both HIV and syphilis seroprevalences were found to be low compared to many regions of Turkey. However, considering the fact that increasing number of immigrants may change prevalences and trends of TTI both in Adana and in Turkey, strict monitorization and yearly reporting of TTI rates seem necessary to be able to take proactive measures.

Killer Cell Immunoglobulin-Like Receptor (KIR) Genotype Distribution in Familial Mediterranean Fever (FMF) Patients.

BACKGROUND Familial Mediterranean fever (FMF) is an autosomal recessive autoinflammatory disease predominantly affecting Mediterranean populations. The gene associated with FMF is the MEFV gene, which encodes for a protein called pyrin. Mutations of pyrin lead to uncontrolled attacks of inflammation, and subclinical inflammation continues during attack-free intervals. Killer cell immunoglobulin-like receptor (KIR) genes encode HLA class I receptors expressed by NK cells. The aim this study was to look for immunogenetic determinants in the pathogenesis of FMF and find out if KIR are related to susceptibility to disease or complications like renal amyloidosis. MATERIAL AND METHODS One hundred and five patients with FMF and 100 healthy individuals were involved in the study. Isolated DNA from peripheral blood was amplified by sequence specific PCR probes and analyzed by Luminex for KIR genotypes. Fisher Exact test was used to evaluate the variation of KIR gene distribution. RESULTS All patients and healthy controls expressed the framework genes. An activator KIR gene, KIR2DS2, was significantly more frequent in FMF patients (p=0.036). Renal amyloidosis and presence of arthritis were not associated with KIR genes and genotype. KIR3DL1 gene was more common in patients with high serum CRP (p=0.016). CONCLUSIONS According to our findings, we suggest that presence of KIR2DS2, which is an activator gene for NK cell functions, might be related to the autoinflammation in FMF. The potential effect of KIR genes on amyloidosis and other clinical features requires studies with larger sample sizes.

Risk factors of carbapenem-resistant Klebsiella pneumoniae infection: a serious threat in ICUs.

BACKGROUND: Nosocomial infections caused by Carbapenem-resistant Klebsiella pneumoniae (CRKP) are increasing. Our aim in this study was to investigate the risk factors of CRKP infections. MATERIAL/METHODS: A retrospective cohort study was performed between 1 January and 31 December 2012 in ICU patients. Data was taken from the hospital infection control database for CRKP. The clinical samples collected from the patients were tested by an automatized system and disk diffusion. SPSS software v11.5 was used for statistical analysis. RESULTS: Totally, 105 Klebsiella pneumoniae isolates were found in 2012 and the carbapenem resistance rate was 48%. The first episode of infection was taken into risk factor analysis. Of the 98 patients, 61 (62.2%) were male and the mean and median ages were 30.4±29.8 and 25 (0-93). The length of stay was longer in the resistant group (p=0.026). Mortality was 48% in the whole group and similar between groups (p=0.533). There was a relationship between meropenem and third-generation cephalosporin use and resistance (OR 3.244 (1.193-8.819) and OR: 3.590 (1.056-12.209). The other risk factors in univariate analysis were: Immunosuppression OR: 2.186 (1.754-2.724), nasogastric catheter OR: 3.562 (1.317-9.634), peripheral arterial catheter OR: 2.545 (1.027-6.307), and being admitted to the neurosurgical unit OR: 4.324 (1.110-16.842). CONCLUSIONS: Restriction of third-generation cephalosporin and carbapenem use and invasive procedures, along with infection control precautions and disinfection policies, may be effective in reducing the carbapenem resistance in ICUs.

Role of KIR genes and genotypes in susceptibility to or protection against hepatitis B virus infection in a Turkish cohort.

BACKGROUND: Killer cell immunoglobulin-like receptors (KIRs) are a family of inhibitory and activating receptors expressed by natural killer (NK) cells and regulate NK cell activity in the innate response against viral infections. The aim of this study was to determine the possibility of KIR genes and genotypes as a candidate for susceptibility to or protection against chronic hepatitis B virus (HBV) infection or spontaneous remission of the infection in a Turkish cohort. MATERIAL AND METHODS: The present study was carried out on 37 patients with chronic HBV infection, 36 patients in spontaneous remission of HBV infection, and 85 healthy subjects. Sequence-specific oligonucleotide probes analysis was used to investigate 16 KIR genes. All data were statistically analyzed by the Fisher exact test. RESULTS: The rate of inhibitory KIR2DL3 (p=0.0) and 3DS1 (p=0.0) were higher in the healthy group than the group composed of chronic HBV patients and patients with spontaneous remission. There were no statistically significant differences between the rate of AA and Bx genotypes of chronic HBV patients and patients with spontaneous remission and the control group (p>0.05). CONCLUSIONS: Our results suggest that KIR2DL3 and KIR3DS1 genes could be protector genes for HBV infection and they could be important immuno-genetic markers in determining antiviral immunity in the Turkish population.

Congenital Toxoplasmosis and Long-term Outcomes

Objective: Congenital toxoplasmosis (CT) can have severe early and late sequelae in children. In this study, we aimed to evaluate the demographic, clinical, treatment characteristics of patients diagnosed with congenital Toxoplasma infection and to highlight the long-term complications of the patients. Methods: Patients with CT were included in this study who were followed between 2010 and 2022 in Cukurova University Medical Faculty Hospital. Demographic, clinical and treatment characteristics were searched retrospectively. In the diagnosis of maternal and CT, Toxoplasma IgM, IgG, IgG avidity, T. gondii polymerase chain reaction tests were used along with clinical and symptoms. Results: Eighteen children (two twins) with CT and their mothers (n=16) were included in the study. Median age was 1 month. Ten (55.5%) of the children were male. CT diagnosis was made during pregnancy in 7 mothers (resulting in 8 babies) and postnatally in 9 mothers (resulting in 10 babies). The mothers of 5 (31.1%) babies with CT received spiramycin treatment during pregnancy. Three (60%) of 5 pregnant women who received spiramycin were diagnosed in the first trimester, 4 (80%) of the babies did not have any sequale and only 1 (20%) had microphthalmia. Ocular involvement was the most common presentation of the disease occured in 10 patients (55.5%), hydrocephalus and intracranial calcification developed in five patients (27.7%). Hearing loss developed in 2 (11.1%) patients. During the follow-up period, seizures developed in 3 patients (16.6%), microcephaly in 2 patients (11.1%), and neurodevolopmental retardation in 7 patients (38.8%), two of the patients had severe mental retardation. One (5.5%) patient with hydrocephalus died at 36 months of age due to complications after ventriculoperitoneal shunt application. Conclusion: In our study, we observed severe sequelae in vision, hearing, and neurodevelopmental aspects in children diagnosed with CT at birth and during follow-ups. Early diagnosis and treatment of infants, along with the detection of Toxoplasma infection during pregnancy, are essential in preventing severe sequelae that may arise due to CT.

Candida parapsilosis candidemia in children admitted to a tertiary hospital in Turkey: clinical features and antifungal susceptibility.

In recent years, the incidence and drug resistance of Candida parapsilosis have increased. Our study aimed to determine the antifungal sensitivity of C. parapsilosis and the clinical and demographic characteristics of children with candidemia. Two hundred pediatric patients with C. parapsilosis candidemia were included in the study between 1 January 2010 and 1 August 2023. Clinical samples were evaluated on a BACTEC-FX-40 automatic blood culture device (Becton Dickinson, USA). Yeast isolates were identified to the species level via identification cards (YST) using the VITEK 2 Compact (bioMeriéux, France) system. Antifungal susceptibility was performed using antifungal cell cards (AST-YST01). Approval for the study was received from the "University Faculty of Medicine" Hospital Clinical Research Ethics Committee. Non-catheter candidemia was detected in 127 (63.5%) patients, and catheter-related candidemia was detected in 73 (36.5%) patients. It was observed that the patients' history of malignancy, mechanical ventilation, urinary catheter, nasogastric tube, and intensive care unit stay was associated with C. parapsilosis mortality. The mortality rate from candidemia was 9.5%. The most frequently preferred antifungal agents were amphotericin B and fluconazole. The fluconazole drug resistance rate was found to be 6%, and the amphotericin B drug resistance rate was 4%. Because C. parapsilosis candidemia mortality rates can be high depending on risk factors and clinical characteristics, it is important to initiate appropriate and timely antifungal therapy. We think that our study can provide important information about the clinical profiles, distributions, susceptibility profiles, and control of antifungal resistance of C. parapsilosis isolates. IMPORTANCE: It has been observed that the frequency and antifungal resistance of Candida parapsilosis have increased recently. In our study, we aimed to determine the antifungal sensitivity of C. parapsilosis and the clinical and demographic characteristics of children with candidemia. It was observed that the patients' history of malignancy, mechanical ventilation, urinary catheter, nasogastric tube, and intensive care stay was associated with C. parapsilosis mortality. The mortality rate from candidemia was 9.5%. The most frequently preferred antifungal agents were amphotericin B and fluconazole. The fluconazole drug resistance rate was found to be 6%, and the amphotericin B drug resistance rate was 4%. Because C. parapsilosis candidemia mortality rates can be high depending on risk factors and clinical characteristics, it is important to initiate appropriate and timely antifungal therapy.

Posttraumatic keratitis caused by Elizabethkingia meningosepticum.

OBJECTIVE: To present a case of bacterial keratitis caused by Elizabethkingia meningosepticum in an eye after trauma. METHOD: Case report. RESULT: A 45-year-old woman was referred to our cornea clinic for keratitis, which had developed following nonpenetrating eye trauma from a tree branch. Cultures from a corneal smear demonstrated heavy growth of E. meningosepticum. Treatment with a combination of topical moxifloxacin and topical trimethoprim/polymyxin B effectively controlled the corneal ulcer. Corneal infection resolved within 2 months, but a central corneal scar and vascularization remained. CONCLUSIONS: E. meningosepticum is an opportunistic bacterium and gives rise to severe systemic infections in immunocompromised patients. Ocular infections caused by this bacterium are extremely rare in the literature. To our knowledge, this is the first report of posttraumatic keratitis caused by E. meningosepticum.

Etiological and Clinical Features of Contact Lens-Associated Microbial Keratitis.

Objectives: To determine the demographic, etiological, microbiological, and clinical characteristics and present treatment results of contact lens (CL)-associated microbial keratitis (CLAMK). Materials and Methods: Medical records of patients who were followed in our clinic for CLAMK between January 2014 and May 2020 were retrospectively analyzed. Demographic characteristics, symptom duration, CL and usage characteristics, risk factors, isolated microorganisms, lesion characteristics, hospital stay, recovery and follow-up times, and best corrected visual acuities (BCVA) at first and last examination were recorded. Results: The 22 patients (16 females, 6 males; 22 eyes) had a mean follow-up time of 13.0±18.3 months and mean age of 26.9±14.3 years. Most of the female patients (13/16) were under 35 years old. At least one risk factor associated with improper CL usage was identified in 21 patients (95.4%). The most common risk factor was sleeping with CL (n=15, 68.1%). Causative microorganisms were detected on microbiological examination in 15 cases (68.1%). The most common microorganism was Pseudomonas aeruginosa (n=8). Causative pathogens were sensitive at rates of 84.2%, 95% and 94.7% to combined vancomycin/amikacin, combined vancomycin/ceftazidime, and moxifloxacin, respectively. Mean BCVA was 0.9±1.1 logMAR in the first examination and increased to 0.59±1.1 at last examination (p=0.006). There was a negative correlation between BCVA at presentation and length of hospital stay (p=0.014). Conclusion: Mistakes in CL use are a frequent predisposing factor in patients with CLAMK. Informing CL users in detail about CL usage and cleaning may reduce the frequency of these mistakes and thus infections. Current antibiotic options that should be preferred in empirical treatment remain largely effective against likely pathogens. Favorable visual outcomes can be obtained in most cases with detailed diagnostic examination and appropriate treatment approaches.

Effect of Heterologous Vaccination Strategy on Humoral Response against COVID-19 with CoronaVac plus BNT162b2: A Prospective Cohort Study.

This study aimed to evaluate the mixed and homogeneous application of the inactivated SARS-CoV-2 vaccine CoronaVac (CV) and the mRNA vaccine BNT162b2 (BNT). This prospective cohort study included 235 health care workers who had received two prime shots with CoronaVac. They were divided into three cohorts after the third month: Cohort-I (CV/CV); Cohort-II (CV/CV/CV); and Cohort-III (CV/CV/BNT). Anti-S-RBD-IgG and total anti-spike/anti-nucleocapsid-IgG antibody concentrations were examined in vaccinated health workers at the 1st, 3rd, and 6th months following the second dose of the vaccination. The mean age of 235 health care workers who participated in the project was 39.51 ± 10.39 (min-max: 22-64). At the end of the 6th month, no antibodies were detected in 16.7% of Cohort-I participants, and anti-S-RDB IgG levels showed a decrease of 60% compared to the levels of the 3rd month. The antibody concentrations of the 6th month were found to have increased by an average of 5.13 times compared to the 3rd-month levels in Cohort-II and 20.4 times in Cohort-III. The heterologous vaccination strategy "CoronaVac and BNT162b2 regimen" is able to induce a stronger humoral immune response and it will help remove inequalities in the developing world where CoronaVac was the initial prime.

Protectivity of COVID-19 Vaccines and Its Relationship with Humoral Immune Response and Vaccination Strategy: A One-Year Cohort Study.

This prospective cohort study aimed to evaluate the efficacy of COVID-19 vaccine schemes, homologous versus heterologous vaccine strategies, and vaccine-induced anti-S-RBD-IgG antibody response in preventing COVID-19 among 942 healthcare workers 1 year after vaccination with the inactivated and/or mRNA vaccines. All participants received the first two primary doses of vaccines, 13.6% of them lacked dose 3, 50.5% dose 4, and 90.3% dose 5. Antibody levels increased with the increase in number of vaccine doses and also in heterologous vaccine regimens. In both inactive, mRNA vaccines and mixed vaccination, infection rates were significantly higher in two-dose-receivers, but lower in four- or five-dose receivers and increasing the total number of vaccine doses resulted in more protection against infection: the three-dose regimen yielded 3.67 times more protection, the four-dose 8 times, and five-dose 27.77 times more protection from COVID-19 infection, compared to any two-dose vaccination regimens. Antibody levels at the end of the first year of four- or five-dose-receivers were significantly higher than two- or three-dose receivers. To conclude, an increased number of total vaccine doses and anti-S-RBD antibody levels increased the protection from COVID-19 infection. Therefore, four or more doses are recommended in 1 year for effective protection, especially in risk groups.