Clinical and immunological outcomes of SARS-CoV-2 infection in patients with inborn errors of immunity receiving different brands and doses of COVID-19 vaccines.

Introduction: Vaccines against severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) provide successful control of the coronavirus-2019 (COVID-19) pandemic. The safety and immunogenicity studies are encouraging in patients with inborn errors of immunity (IEI); however, data about mortality outcomes and severe disease after vaccination still need to be fully addressed. Therefore, we aimed to determine the clinical and immunological outcomes of SARS-CoV-2 infection in patients with IEI who have received vaccination. Materials and Methods: Eighty-eight patients with a broad range of molecular etiologies were studied; 45 experienced SARS-CoV-2 infection. Infection outcomes were analyzed in terms of genetic etiology, background clinical characteristics, and immunization history, including the type and number of doses received and the time elapsed since vaccination. In addition, anti-SARS-CoV-2 antibodies were quantified using electrochemiluminescent immunoassay. Results: Patients were immunized using one of the three regimens: inactivated (Sinovac, Coronavac®), mRNA (BNT162b2, Comirnaty®, Pfizer-Biontech), and a combination. All three regimens induced comparable anti-SARS-CoV-2 IgG levels, with no differences in the adverse events. Among 45 patients with COVID-19, 26 received a full course of vaccination, while 19 were vaccine-naive or received incomplete dosing. No patients died due to COVID-19 infection. The fully immunized group had a lower hospitalization rate (23% vs. 31.5%) and a shorter symptomatic phase than the others. Among the fully vaccinated patients, serum IgM and E levels were significantly lower in hospitalized patients than non-hospitalized patients. Conclusion: COVID-19 vaccines were well-tolerated by the IEI patients, and a full course of immunization was associated with lower hospitalization rates and a shorter duration of COVID-19 symptoms.

Evaluation of Sysmex-UF 5000-BF Module for Sterile Body Fluids. An Alternative for Conventional Methods?

BACKGROUND: Infections of cerebrospinal fluid (CSF), peritoneal and pleural fluids often result in severe morbidity and mortality. Cytometric analysis, cell count, and cell differentiation is supportive in rapid clinical decision. The aim of this study is to evaluate the performance of Sysmex UF-5000 (Sysmex Co., Kobe, Japan) in body fluid (BF) mode for white blood cells and bacterial counting and compare the results with manual microscopy, gram staining, and culture as reference method. METHODS: A total of 634 body fluid samples (433 CSF, 100 pleural, and 101 peritoneal fluid) submitted to our clinical microbiology laboratory between December 2018 and January 2020 were enrolled in the study. Specimens were analyzed for white blood cell (WBC) counts with Sysmex UF-5000-BF mode. The results were grouped into five categories and compared with the conventional methods as reference method. The relationship between culture results and Sysmex UF5000-BF bacterial load and WBC count were evaluated for the detection of infection. RESULTS: The categorical agreement of UF 5000-BF mode was very strong for CSF (correlation coefficient: 0.70, p < 0.05) and good agreement was found for pleural and peritoneal samples (correlation coefficient: 0.63, p < 0.05). Sensitivity was 100% and specificity was 64% in pleural samples. For ascites sensitivity and specificity were found as 94.1% and 77.4%, and for CAPD samples as 100% and 81,2% respectively. Bacterial and WBC count with flow cytometry was higher among culture positive samples (p < 0.05). The same significant difference was detected between the UF 5000-BF bacterial counts and the samples in which bacteria were detected in the gram preperation (p < 0.05). WBC count by UF-5000-BF was also higher among culture positive compared to culture negative samples (p < 0.05). CONCLUSIONS: Our results demonstrated that the flow cytometric method, Sysmex UF-5000 body fluid (BF) mode, can be an alternative particularly in CSF samples. Detection of 100% sensitivity in peritoneal and pleural samples can prevent unnecessary antibiotic treatment and possible resistance development. Besides, automated bacterial counting can be used for rapid prediction of a positive body fluid culture.

Evaluation of the Diagnostic Value of Cell Population Data in Sepsis in Comparison to Localized Infection, Chronic Inflammation, and Noninfectious Inflammation Cases.

INTRODUCTION: Sepsis, defined as an increase of 2 points or more in the sequential organ failure assessment score, is a life-threatening organ dysfunction caused by the dysregulated host response to infection. Volume-conductivity-scatter (VCS) parameters of cell counters which are known as cell population data (CPD) have been suggested to be beneficial in diagnosing sepsis. We aimed to evaluate the diagnostic value of CPD parameters in sepsis in comparison to nonsystemic infection cases (NSI) and non-infectious acute and chronic inflammatory conditions. MATERIALS AND METHODS: We prospectively included four groups of patients" data: sepsis (n = 66), localized infection (pneumonia, n = 59), chronic inflammation (rheumatoid arthritis, n = 92) and noninfectious inflammation (coronary artery bypass graft operation, n = 56) groups, according to their clinical status and laboratory results. Samples for cell counting and serum markers were collected on the same day of culture collection. VCS parameters were measured by Unicel DxH800 Coulter Cellular Analyzer (Beckman Coulter, USA). RESULTS: Mean neutrophil volume (MN-V-NE), was highest in the sepsis group [155(149-168)] compared to the localized infection [148(140-158)], chronic inflammation [144.5(142-149)] and noninfectious inflammation [149(145.2-153.7)] (P = 0.001, P < 0.001, P < 0.001, respectively). Neutrophil volume SD (SD-V-NE) was higher in the sepsis [21(18.8-23.7)], significantly differentiating sepsis from other groups. The area under curves of procalcitonin and hs-C-reactive protein were 0.846 and 0.837, respectively, in the receiver-operating characteristic curves (ROC) . CPD combinations, (SD-V NE + SD-V LY + SD-V MO), (SD-V NE + SD-V MO), and (MN-V NE + SD-V NE + SD-C LY + SD-V MO) had greater AUC values than procalcitonin's. CONCLUSION: VCS parameters might be promising for differentiating sepsis and non-sepsis cases. Additionally, obtaining these data routinely makes their prospects promising without any additional cost and time.

Performance of Sysmex UF-5000 for candiduria screening.

In this study, we tested the performance of the Sysmex UF-5000 system to detect yeast-like cell (YLC) counting to screen for candiduria. Urine samples were screened for leukocyte and yeast amount by flow cytometry and results were compared with fungal culture results. A total of 56,749 urine samples were enrolled in this study. Urine culture and urinalysis of YLC data were used to evaluate the performance of YLC in diagnosing candiduria. Different cut-off values (YLC. 5, 10, 20, 50, 100/µl) were evaluated. Youden index was used to determine the ideal cut-off value, and the highest was 0.95 with 5 YLC/µl. When the cut-off value for YLC is 5 cells/µl, 95.15% of the samples were "negative" with flow cytometry and culture (NPV:100%). In conclusion, detection of YLC by flow cytometer (Sysmex UF-5000) can be a rapid alternative method to exclude candiduria prior to urine culture.

An alternative for urine cultures: Direct identification of uropathogens from urine by MALDI-TOF MS.

Urinary tract infections are one of the most common bacterial infections and rapid diagnosis of the infection is essential for appropriate antibiotic therapy. The goal of our study was to identify urinary pathogens directly by MALDI-TOF MS and to perform antibiotic susceptibility tests in order to shorten the period spent for culturing.Urine samples submitted for culture to the Clinical Microbiology Laboratory were enrolled in this study. Urine samples were screened for leukocyte and bacteria amount by flow cytometry. Samples with bacterial load of 106-107/mL were tested directly by MALDI-TOF MS and antibiotic susceptibility tests (AST) were performed.In total, 538 positive urine samples were evaluated in our study. MALDI-TOF MS identified the microorganism directly from the urine sample in 91.8% of these samples and the concordance rate of conventional identification and direct detection was 95.8% for Gram-negatives at the genus and species level. Escherichia coli (n:401) was the most frequently isolated microorganism, followed by Klebsiella pneumoniae (n:57). AST results were generated for 111 of these urine samples and the concordance was 90% and 87% for E. coli and K. pneumoniae, respectively.Our results showed that screening of urine samples with flow cytometry to detect positive samples and identification of uropathogens directly by MALDI-TOF MS with an accuracy of over 90% can be a suitable method particularly for Gram-negative bacteria in clinical microbiology laboratories.

Evaluation of the performance of MALDI-TOF MS and DNA sequence analysis in the identification of mycobacteria species

Background/aim: Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry is an alternative way of identifying mycobacteria via the analysis of biomolecules. It is being increasingly used in routine microbiology practice since it permits early, rapid, and cost-effective identification of pathogens of clinical importance. In this study, we aimed to evaluate the efficacy of phenotypic identification of mycobacteria by the MALDI-TOF MS MBT Mycobacteria Library (ML) 4.0 (Bruker, Daltonics) compared to standard sequence analysis. Materials and methods: A total of 155 Mycobacterium clinical and external quality control isolates, comprising nontuberculous mycobacteria (NTM) (n = 95) and the Mycobacterium tuberculosis complex (MTC) (n = 60), were included in the study. Results: Identification by MBT ML4.0 was correctly performed in 100% of MTC and in 91% of NTM isolates. All of the MTC isolates were correctly differentiated from NTM isolates. Conclusion: Based on our results, MBT ML4.0 may be used reliably to identify both NTM and MTC.

Detection of vancomycin-resistant enterococci (VRE) in stool specimens submitted for Clostridium difficile toxin testing.

The aim of this study was to determine the association between Clostridium difficile (C. difficile) and vancomycin-resistant Enterococcus (VRE) and efficacy of screening stools submitted for C. difficile toxin assay for prevalence of VRE. Between April 2012 and February 2014, 158 stool samples submitted for C. difficile toxin to the Marmara University Microbiology Laboratory, were included in the study. Stool samples were analyzed by enzyme immuno assay test; VIDAS (bioMerieux, France) for Toxin A&B. Samples were inoculated on chromID VRE (bioMerieux, France) and incubated 24h at 37°C. Manuel tests and API20 STREP (bioMerieux, France) test were used to identify the Enterococci species. After the species identification, vancomycin and teicoplanin MIC's were performed by E test and molecular resistance genes for vanA vs vanB were detected by polymerase chain reaction (PCR). Of the 158 stool samples, 88 were toxin positive. The prevalence of VRE was 17%(n:19) in toxin positives however, 11.4% in toxin negatives(n:70). All VRE isolates were identified as Enterococcus faecium. These results were evaluated according to Fischer's exact chi-square test and p value between VRE colonization and C. difficile toxin positivity was detected 0.047 (p<0.05). PPV and NPV were 79% and 47% respectively. In our study, the presence of VRE in C. difficile toxin positives is statistically significant compared with toxin negatives (p<0.05). Screening for VRE is both additional cost and work load for the laboratories. Therefore VRE screening among C. difficile toxin positive samples, will be cost effective for determination of high risk patients in the hospitals especially for developing countries.

Comparison of MALDI-TOF MS, nucleic acid hybridization and the MPT64 immunochromatographic test for the identification of M. tuberculosis and non-tuberculosis Mycobacterium species.

Mycobacteria are an important cause of morbidity in humans. Rapid and accurate mycobacterial identification is important for improving patient outcomes. However, identification of Mycobacterium species is not easy, due to the slow and fastidious growth of mycobacteria. Recently, biochemical, sequencing, and probing methods have come to be used for identification. This study compared the performance of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the identification of M.tuberculosis and non-tuberculosis Mycobacteria (NTM) to those of nucleic acid hybridization (NAH) and the MPT64 immunochromatographic test. A total of 69 isolates from Marmara University Hospital, Microbiology Laboratory obtained between 2012 and 2013 were included in our study. All strains were grown on Lowenstein-Jensen and Middlebrook 7H9 medium. Among the 69 isolates, 56 (81%) were isolated as Mycobacterium tuberculosis complex (MTC), and 13 (19%) were isolated as NTM by the MPT64 ICT. NAH was able to identify all isolates to the species level. The isolated NTM included M. intracellulare (n:5), M. lentiflavum (n:3), M. xenopi (n:2), M. malmoense (n:1), M. abscessus (n:1), and M. avium (n:1). MALDI-TOF MS identified 88% of the mycobacterial isolates. All M. tuberculosis strains were identified correctly, but the ratio was 38.5% for NTM. Mycobacterial identification using MALDI-TOF MS takes 45 minutes and costs 3 Euro/test, whereas mycobacterial identification using NAH takes 6-7 hours and costs 30 Euro/test. In conclusion, MALDI-TOF MS has the potential to identify mycobacteria in the clinical laboratory setting by reducing identification turnaround time and laboratory costs for isolate referral.

Intravesical hyaluronic acid treatment improves bacterial cystitis and reduces cystitis-induced hypercontractility in rats.

OBJECTIVE: To investigate the effect of intravesical hyaluronic acid on Escherichia coli-induced cystitis and cystitis-induced hypercontractility in rats. METHODS: Bacterial cystitis was induced in Wistar female rats by intravesical inoculation of E. coli. Isotonic saline was instilled in the control group (n = 6). The rats were either non-treated, treated with gentamycin (4 mg/kg, 5 days) or treated intravesically with hyaluronic acid (0.5 mL, 0.5%). On the eighth day, the bladder tissues were excised for histological examination, and the measurements of myeloperoxidase, superoxide dismutase and catalase activities. Contraction/relaxation responses to carbachol, isoprotrenol and papaverine were studied. RESULTS: Tissue myeloperoxidase activity was increased, but superoxide dismutase and catalase activities were decreased in bacterial cystitis, while hyaluronic acid treatment reversed these changes. In the hyaluronic acid-treated group, healing of the uroepithelium was observed, while decreased inflammatory cell infiltration was obvious in gentamycin-treated group. E. coli-induced cystitis in all rats resulted in increased contraction responses to carbachol compared with controls (P < 0.01). Treatment with hyaluronic acid, but not gentamycin, significantly (P < 0.05) depressed hypercontractility at maximum carbachol concentrations. In all rats with cystitis, papaverine-induced relaxation was increased, whereas isoproterenol-induced relaxation curves were not different between the studied groups. CONCLUSION: Gentamycin treatment, despite its ameliorative effect on inflammation, had no impact on the contractile dysfunction of the injured bladder. Intravesical hyaluronic acid, in addition to its supportive role in the healing of the epithelium, seems to lower the increased threshold for contraction and to reduce oxidative stress. These findings support a potential role for hyaluronic acid in the treatment of bacterial cystitis.

[Can meropenem E-test be used to estimate the presence of carbapenem resistance gene cfiA among Bacteroides fragilis strains?]. / Meropenem E-test, bacteroides fragilis suslarinda karbapenem direnç geni cfiA varligini tahmin etmede kullanilabilir mi?

Bacteroides fragilis, which is found in normal colon flora, is the most commonly encountered pathogen in anaerobic infections and more resistant to antimicrobial agents than the other anaerobes. Limited number of antibiotics; such as carbapenems, beta-lactam/beta-lactamase inhibitors and nitroimidazoles are the most effective antibiotics against Bacteroides, however resistant isolates to these antimicrobials have been reported recently. Resistance against carbapenems occurs due to a metallo-beta-lactamase enzyme expressed by cfiA gene. While agar dilution method is used to test the antimicrobial susceptibility of anaerobic organisms, E-test is recommended for susceptibility testing of anaerobes associated with life-threatening infections with high mortality and morbidity. In this study, meropenem E-test was used to determine the carbapenem resistance of B.fragilis strains and to estimate the presence of cfiA gene. A total of 63 B.fragilis strains that were previously isolated from clinical samples (of which 16 were from stool samples) in our laboratory, were enrolled in the study. Minimum inhibitory concentration (MIC) values were determined by meropenem E test (AB Biodisk, Sweden) and presence of cfiA genes were investigated by in-house polymerase chain reaction. The MIC ranges of meropenem were < 0.002 - > 32 µg/ml and the resistance rate was 9.5% (6/63). Thirty-three percent (21/63) of strains harboured cfiA gene. A statistically significant relation (p< 0.0001) was determined between presence of cfiA gene and high MIC value (MIC 0.5 µg/ml). The proportion of cfiA-positive isolates detected in this study was substantially higher than that reported in other countries. This might be attributed to the frequent use of carbapenems in our hospital. The results of this study indicated that meropenem E-test method could be useful to estimate the presence of cfiA gene in B.fragilis strains and thus to detect the resistant strains.

[Neonatal Candida infections and the antifungal susceptibilities of the related Candida species]. / Neonatal kandida enfeksiyonlari ve etkenlerinin antifungal duyarliliklari

Among nosocomial infections in the newborns, the incidence of fungal infections has been rising over the last decades. Fluconazole has been a new option for treatment however, expanded use of the drug brought up the development of resistance. In this study, species of the Candida isolates from neonates with candida infections, their antifungal susceptibilities and the effectiveness of the therapy were evaluated. All the species of Candida isolates from blood, urine and sterile body fluids of 54 neonates and their antifungal susceptibilities were evaluated retrospectively over the 13-year period. Demographic characteristics, risk factors, infection foci, Candida species causing infection and their in vitro susceptibilities for fluconazole (FCZ) and amphotericin B (AMB) and treatment responses were analyzed. The antifungal susceptibility testing of isolates was performed by microdilution technique. The median birth weight and gestational age of the study groups were 1735 (660-3990) g and 33 (24-40) weeks, respectively. Among the patients, 19 (35%) were term, while 35 (65%) were preterm [< 32 weeks n = 20 (37%), < 28 weeks n = 7 (13%)]. The percentage of low birth weight infants was 65% (42% was < 1500 g, 13% was < 1000 g). Candida spp. were isolated mostly from blood samples (63%), followed by urine (46%), cerebrospinal fluid (CSF; 5%), peritoneal fluid (3%) and endotracheal aspirate (2%). Multifocal growth was determined in 10 (18%) cases. The isolated species were C.albicans (n =36) as being the most common isolate followed by C.parapsilosis (n = 12), C.tropicalis (n = 1), C.kefyr (n = 1), C.lusitaniae (n = 1), C.pelluculosa (n = 1) and Candida spp. (n = 2). Prior antibiotic use, long term hospitalization, total parenteral nutrition and use of lipid solutions, prematurity and catheter use were determined as the most frequently associated factors causing candidal infections. A congenital abnormality, mainly myeloschisis and hydrocephaly, was detected in 18 (33%) of the cases. Overall FCZ resistance rate was 5.5% and the rate of resistance according to the species was 2.8% for C.albicans and 11% for non-albicans isolates. No resistance was observed to AMB. Initial treatment was FCZ for 78% and AMB for 22% of the newborns. The treatment was switched to AMB in 15 (28%) cases because of no clinical or laboratory response to FCZ although only three of these babies showed resistance to FCZ (MIC ≥ 64 mcg/ml). Among the cases with no clinical/microbiological response, C.albicans was the most frequently (66%) isolated species followed by non-albicans species (33%). All of the isolates in the study group were susceptible to AMB and the rate of FCZ resistance was 5.5%. However, it was noted that the clinical treatment failure was higher than the resistance rate when FCZ was considered. Although antifungal susceptibility tests are helpful for guiding the therapy, in vivo and in vitro differences should be taken into account in case of treatment failure encountered with the use of in vitro effective agents.

Rapid reporting of urine culture results: impact of the uro-quick screening system.

This study evaluated the impact of the Uro-Quick (UQ) screening system (Alifax, Italy) for a rapid and accurate reporting of urine cultures, and whether it can provide bacterial yield to be used in identification and susceptibility testing. A total of 1480 urine samples collected between October 2006 and July 2008 were tested by conventional culture (CC) methods and UQ simultaneously. Sediments of positive UQ vials were used as bacterial yields for identification and susceptibility testing procedures. Of the 1480 samples, 999 revealed bacteria and/or leukocytes in direct microscopy. Among these 999 samples, positive growth was detected in 420 (42%) and 433 (43.3%) by UQ and CC, respectively. However, only 0.6% of samples without bacteria and leukocytes exhibited positive growth. When compared to CC, UQ demonstrated high levels of positive predictive value (95.9%), negative predictive value (94.8%), sensitivity (93%) and specificity (96.9%). Both CC isolates and UQ bacteria showed 81.3% concordance in identification results. Susceptibility testing of UQ bacteria displayed >90% agreement, when compared with standardized disk diffusion test. Our results indicate that UQ can reliably be used in routine laboratories giving microbial growth results in 3 hours. The most significant part of the study is that bacterial yields of UQ positive samples can be used in identification and susceptibility testing, allowing a rapid, same-day reporting of urine cultures.

[Trends in antibiotic susceptibility patterns of Streptococcus pneumoniae and Haemophilus influenzae isolates: four years follow up]. / Streptococcus pneumoniae ve Haemophilus influenzae izolatlarinin antibiyotik duyarlilik paternlerindeki degisim: dört yillik izlem.

This study was aimed to follow up the antibiotic resistance trends in Streptococcus pneumoniae and Haemophilus influenzae isolated from clinical specimens between 2003-2006 at Marmara University Hospital, Istanbul, Turkey. Antibiotic susceptibilities were performed by disk diffusion method, and penicillin susceptibility was determined by E-test (AB Biodisk, Sweden). Results were evaluated by CLSI standards. During this period a total of 258 S. pneumoniae and 548 H. influenzae were isolated in our laboratory. According to the 2006 CLSI penicillin breakpoints, overall resistance of S. pneumoniae isolates to penicillin was 39.9% and intermediate and high level penicillin resistance rates were 30.2% and 9.7%, respectively. The rates of high level penicillin resistant pneumococci by years were 11.1% in 2003; 10.9% in 2004; 6% in 2005, 12.1% in 2006 and except for 2005 no significant change in resistance rates was detected. However, according to the 2008 CLSI penicillin breakpoints, resistance was found to be 3.5%, intermediate and high level penicillin resistance being 3.1% and 0.4%, respectively. While penicillin resistance rates by years were as 4.4% in 2003, 5.5% in 2004, 0% in 2005 and 4.4% in 2006, high level penicillin resistance was detected only in 2003 as 2.2%. Resistance rates of chloramphenicol, erythromycin, tetracyline and trimethoprim-sulphametoxazole (TMP-SMX) were detected as 10.1%, 19%, 26.8% and 49.2%, respectively while erythromycin, tetracycline and TMP-SMX multi-drug resistance was detected in 12.4% of the isolates. No resistance was detected to vancomycin. Beta-lactamase production rate in H. influenzae isolates was 3.3%, being 1.6% in 2003 with a raise up to 4% in 2006. No beta-lactamase negative ampicillin-resistant isolate was detected. Although chloramphenicol and cefaclor resistance were in low levels (2.2% and 0.7%, respectively), TMP-SMX resistance was detected as 25.5%. TMP-SMX resistance was two fold more in beta-lactamase producers compared with the non-producers, whereas chloramphenicol resistance revealed a significant increase in beta-lactamase producers (1% versus 44.5%). In conclusion, doubling of beta-lactamase production rate in H. influenzae within years indicates the importance of continuous follow-up of antibiotic resistance in specific pathogens. The evaluation of penicillin results obtained for pneumococci according to modified 2008 CLSI criteria revealed that penicillin can still be used effectively in the treatment of pneumococcal respiratory tract infections. Continuous active surveillance of resistance rates provides important data for the determination of the empirical therapy protocols for S. pneumoniae and H. influenzae infections.

Nasopharyngeal carriage of penicillin-resistant Streptococcus pneumoniae in healthy children.

Streptococcus pneumoniae carriage is a risk factor for the development of respiratory system infections and the spread of penicillin-resistant strains. The aim of this study was to investigate nasopharyngeal carriage of S. pneumoniae in healthy children and resistance to penicillin and other antimicrobials and to assess related risk factors. Nasopharyngeal specimens collected from healthy children less than six years of age, visiting a Mother and Child Health Center for health control, were investigated microbiologically between February-March 2004. Carriage rate was 37.2% (n=112/301); 33.9% intermediate and 5.4% high penicillin resistance were detected. According to multivariate analysis, carriage rate was inversely related to number of rooms (OR:0.574) and child age (OR:0.978), while penicillin resistance was correlated well with antibiotic use in the last two months (OR:2.193). Decreased sensitivity plus resistance to other antimicrobials were: trimethoprim-sulfamethoxazole (TMP-SMX) 45.6%; erythromycin 16.1%, tetracycline 16.1%; clindamycin 9.8%, and ofloxacin 3.6% in pneumococcal isolates, which increased significantly (p<0.05) to 72.7%, 31.8%, 27.3%, 20.5%, and 6.8%, respectively, in penicillin non-sensitive S. pneumoniae (PNSSP) except for ofloxacin. Overall multidrug resistance was 17.9%, while PNSSP exhibited a resistance rate of 38.6%. In conclusion, S. pneumoniae carriage rates determined in healthy children were high and PNSSP strains also showed increased resistance to other antimicrobials.

Downregulation of the expression of bone morphogenetic protein 7 in experimental pyelonephritis.

Bone morphogenetic protein 7 (BMP 7) is a member of the transforming growth factor (TGF) beta superfamily and is involved in regeneration, repair, and development of specific tissues, for example kidney, gut, lens, and skeleton. BMP 7 has emerged as a renotrophic factor and experimental studies have shown its protective role against fibrotic processes. Tubulointerstitial changes are present in the pyelonephritic kidney which progresses to fibrosis. Renal fibrosis may lead to significant morbidity in the form of hypertension, proteinuria, and loss of renal function. The objective of this study was to investigate BMP 7 expression in experimental acute and chronic pyelonephritis models. Eighteen Wistar rats were injected with 0.1 mL solution containing E. coli ATCC 25922 10(10) cfu mL(-1) into left renal medullae. Six rats were used as a sham group and were given 0.1 mL 0.9% NaCl. Pyelonephritic rats were sacrificed 24 h (group I, n=6), 1 week (group II, n=6), and 6 weeks (group III, n=6) after E. coli injection. Serum creatinine levels were analyzed. Renal tissues were studied histopathologically by use of hematoxylin and eosin and scored for diagnosis of pyelonephritis. BMP 7 expression was studied semiquantitatively by immunohistochemical staining. Acute (group I) and chronic (group II and group III) pyelonephritic histopathological changes were observed in experimental pyelonephritic groups. A gradual decrease in BMP 7 expression was observed in the tubulointerstitial and tubular area of the pyelonephritic kidneys, mildest in the acute pyelonephritic group and most severe in the chronic pyelonephritic 6th week group. A statistically significant difference was observed between tubulointerstitial BMP 7 expression by groups I and III (P=0.017) and by groups III and IV (P=0.000). Tubular BMP 7 expression was statistically significantly different between groups II and IV (P=0.009) and between groups III and IV (P=0.002). The data imply that BMP 7 has a major role in chronic pyelonephritis. Tubulointerstitial and tubular BMP 7 expression also had a significant negative correlation with fibrosis, tubular, atrophy, and vascular changes. Serum creatinine levels of the study group were all normal. We conclude that the decrease in renal BMP 7 expression in experimental chronic pyelonephritis is one of the factors responsible for fibrotic changes in persistent renal damage.

The relationships between candidemia and candidal colonization and virulence factors of the colonizing strains in preterm infants.

Premature infants are at high risk of developing candidal infections originating from their own normal flora or from the hospital environment. This study involves the surveillance cultures and blood cultures of candidemic preterm infants with low birth weights who have been analyzed for colonization period and status, and for virulence factors such as acid proteinase and phospholipase. Arbitrarily primed-polymerase chain reaction (AP-PCR) was applied to the blood culture isolates of the babies with candidemia and their last colonizing strains in order to determine whether the source of fungemia was the rectum. Of 65 colonized infants, 6.2% developed candidemia with identical strains originating from their rectum according to their PCR patterns. Our findings indicate that the properties of the colonizing yeasts such as increase in number--although not statistically significant because of the small sample size--and/or exhibition of strong hydrolytic enzyme activities through a long duration of colonization might contribute to the development of candidemia in preterms.

[The epidemiology of nasopharyngeal colonisation of Streptococcus pneumoniae in children with respiratory tract infection]. / Solunum yolu enfeksiyonu olan çocuklarda nazofarenksde Streptococcus pneumoniae kolonizasyon epidemiyolojisi.

Nasopharyngeal swab specimens from 324 children with respiratory tract infections were evaluated to detect the rate of Streptococcus pneumoniae colonisation. S. pneumoniae was detected in 92 (28%) of the subjects. Forty three (46.7%) of the isolates were serotyped by the capsular swelling tests. The most common serotypes were 19F, 6B, 3 and 23F. The 7, 9 and 11 valent conjugate pneumococcal vaccines covered 35.8%, 40% and 46.7% of all the S. pneumoniae isolates, respectively. Thirty two (34.8%) isolates exhibited penicillin MIC values between 0.1 and 1 microg/ml, only 1 isolate had MIC > or = 2 microg/ml. Penicillin resistant pneumococcal colonisation was most frequently detected in children with viral upper respiratory tract infections (12.5%). Resistance rates of trimetoprim-sulfamethoxazole, erythromycin, chloramphenicol, clindamycin, ceftriaxone, rifampin were 31.5%, 9.8%, 6.5%, 4.3%, 1%, 0%, respectively. Being a children of a family with low income was the only risk factor for colonisation with S. pneumoniae, whereas having a sibling attending to a day care center, antibiotic use in the last three months and use of more than one antibiotic were significant risk factors for colonisation with penicillin resistant S. pneumoniae (p < 0.05).

Surveillance of Haemophilus influenzae among respiratory tract samples of Turkish children.

We conducted three prospective studies of Haemophilus influenzae in different groups of children. Pharyngeal swab samples were taken (i). from 1382 healthy infants and children between 0 and 10 years of age (group 1), attending well child clinics (n=438), day care centres (n=440) and elementary schools (n=504), and (ii). from 322 children aged 2-10 years (group 2), clinically diagnosed as having upper respiratory tract infection. Pharyngeal swab samples and sinus aspirates were obtained from 49 children between 2 and 9 years of age (group 3), clinically diagnosed as having sinusitis. H. influenzae was isolated in similar rates from 315 (22.7%) of children in group 1, 72 (22.3%) of children in group 2 and 12 (24.4%) of children in group 3. Serotype b comprised 7, 5.2 and 2% of all H. influenzae isolates for group 1, 2 and 3, respectively. Production of beta-lactamase was detected in 1.0% of H. influenzae type b isolates in group 1, 1.2 and 6.1% of all isolates in group 2 and 3, respectively. There were no beta-lactamase negative ampicillin-resistant strains.

Pharyngeal colonization with Haemophilus influenzae type b among healthy Turkish infants and children.

BACKGROUND: An absence of Haemophilus influenzae type b (Hib) disease surveillance and epidemiological data on the pharyngeal carriage of Turkish children causes delay in the introduction of conjugated Hib vaccination into proposed national vaccination programs. METHODS: Oropharyngeal cultures were obtained from 1404 healthy infants and children. Six healthy child clinic (HCC), 11 day-care centers (DCC) and seven elementary schools (ES) were randomly selected in seven different counties at the Anatolian side of Istanbul between January and April 2000. RESULTS: Haemophilus influenzae was isolated from 315 (22.8%) of all participants and 98 (31%) isolates were serotype b. The carriage rate for Hib was higher in children at DCC (43 out of 448, 9.6%) and ES (46 out of 504, 9.1%) compared to infants 0-24 months of age (nine out of 430, 2.1%) presented to HCC. All Hib isolates were susceptible to azithromycin, chloramphenicol and cefotaxime. Beta-lactamase production was detected in only one isolate. Trimethoprim-sulfamethoxazole resistance was found in 8.5% of Hib isolates. Multivariate analysis showed that DCC and ES attendance were independent predictors of Hib carriage. CONCLUSION: A significant proportion of healthy Turkish children was shown to be colonized with Hib. The burden of invasive Hib infections should be determined in order to evaluate the Hib conjugated vaccine as a part of a routine immunization program in Turkey.