Mustafa Bakir - Academia.edu (original) (raw)

Papers by Mustafa Bakir

Mikrobiyol …, 2010

... Emel ALTUNCU1, Hülya BİLGEN1, Nilgün ÇERİKÇİOĞLU2, Arzu İLKİ2, Nurver ÜLGER2, Mustafa BAKIR3,... more ... Emel ALTUNCU1, Hülya BİLGEN1, Nilgün ÇERİKÇİOĞLU2, Arzu İLKİ2, Nurver ÜLGER2, Mustafa BAKIR3, İpek AKMAN1, Eren ÖZEK1 ... Hastaların demografik verileri, risk faktörleri, enfeksiyon odağı, enfeksiyona yol açan Candida türleri ile flukonazol (FKZ) ve amfoterisin B ...

Pediatric blood & …, 2006

We describe an 8-year-old boy who presented with multiple unresectable aspergillus brain abscesse... more We describe an 8-year-old boy who presented with multiple unresectable aspergillus brain abscesses as the initial presentation of X-linked chronic granulomatous disease (CGD). He failed initial therapy with amphotericin B, but was subsequently salvaged with voriconazole. CGD should be considered in the differential diagnosis for all children presenting with invasive fungal infections, particularly, those involving the central nervous system (CNS). Whereas, optimal pharmacologic therapy is still unknown for CNS aspergillosis, voriconazole may have an advantage due to its ability to cross the blood brain barrier and excellent oral absorption and bioavailability.

British journal of neurosurgery, Jan 28, 2018

Ventriculoperitoneal shunt (VPS) is the most common treatment modality for hydrocephalus. However... more Ventriculoperitoneal shunt (VPS) is the most common treatment modality for hydrocephalus. However, VPS infection is a common and serious complication with high rates of mortality and morbidity. The objective of this study was to investigate causative agents and the management of VPS infections and to identify risk factors for re-infection in children. Retrospective, multicentre study on patients with VPS infection at paediatric and neurosurgery departments in four tertiary medical centres in Turkey between January 2011 and September 2014. A total of 290 patients with VPS infections were identified during the study period. The aetiology of hydrocephalus was congenital malformations in 190 patients (65.5%). The most common symptom of shunt infection was fever in 108 (37.2%) cases. At least one pathogen was identified in 148 VPS infections (51%). The most commonly isolated pathogen was coagulase-negative staphylococci, which grew in 63 cases (42.5%), followed by Pseudomonas aeruginosa ...

The Pan African medical journal, 2016

Fungal infections like Paecilomyces keratitis have emerged in childhood recently. The diagnosis a... more Fungal infections like Paecilomyces keratitis have emerged in childhood recently. The diagnosis and treatment of Paecilomyces keratitis is difficult and the outcome is usually poor. Corneal culture should be performed on fungal media such as Sabouraud glucose neopeptone agar (SDA) as soon as possible for diagnosis. We report a rare case of Paecilomyces keratitis in an immunocompetent child, which was unresponsive to amphotericin B. The case was managed by a multidisciplinary approach involving the departments of ophthalmology, microbiology and pediatric infectious diseases. We want to draw attention once again that fungal keratitis caused by unusual agents are increasing. Physicians should consider fungal causes of keratitis, in patients with some predisposing factors like ocular surgery and prolonged use of topical corticosteroids.

Wounds : a compendium of clinical research and practice, 2016

Asian Pacific journal of allergy and immunology, Jan 12, 2016

Infections due to non-tuberculous mycobacteria species are problematic for immunodeficient indivi... more Infections due to non-tuberculous mycobacteria species are problematic for immunodeficient individuals. Mendelian susceptibility to mycobacterial diseases (MSMD) defines a group of genetic defects affecting cellular interactions and the interferon (IFN)-γ pathway. Patients with MSMD may present with a disseminated infection resulting from the Bacillus Calmette-Guerin vaccine, Mycobacterium tuberculosis complex, environmental nontuberculous mycobacteria or Salmonella species. Atypical mycobacterial infections and deficient granuloma or giant cell formation are important indicators for MSMD, especially in patients with a family history of parental consanguineous marriage. Herein we report the case of a boy with an IL-12Rβ1 defect who presented with massive intraabdominal lymphadenopathy due to Mycobacterium intracellulare infection. The patient was born to consanguineous parents, both heterozygous for the IL-12Rβ1 defect mutation. Debulking surgery was planned in order to decrease the...

Journal of Infection and Public Health, 2017

Raoultella planticola is rarely associated with clinical infection, and a limited number of pedia... more Raoultella planticola is rarely associated with clinical infection, and a limited number of pediatric cases have been reported. Herein we report a case of bacteremia presumptively secondary to bilateral conjunctivitis in an infant caused by R. planticola which was successfully treated with piperacillin-tazobactam. It should be kept in mind that R. planticola can be a pathogen in pediatric age groups.

Medical Mycology Case Reports, 2017

Although Saccharomyces boulardii is usually a non-pathogenic fungus, in rare occasions it can cau... more Although Saccharomyces boulardii is usually a non-pathogenic fungus, in rare occasions it can cause invasive infection in children. We present the case of an 8-year-old patient in pediatric surgical intensive care unit who developed S. cerevisiae fungemia following probiotic treatment containing S. boulardii. Caspofungin was not effective in this case and he was treated with amphotericin B. We want to emphasize that physicians should be careful about probiotic usage in critically ill patients.

BMC Microbiology, 2017

Background: The aim of this study is to compare the diagnostic performance of the line probe assa... more Background: The aim of this study is to compare the diagnostic performance of the line probe assay (LPA) with conventional multiplex polymerase chain reaction (PCR) for Streptococcus pneumoniae as well as real-time PCR for Neisseria meningitidis and Haemophilus influenzae type b (Hib) in cerebrospinal fluid (CSF) samples from children during the multicenter national surveillance of bacterial meningitis between the years 2006 and 2009 in Turkey. Results: During the study period 1460 subjects were enrolled and among them 841 (57%) met the criteria for probable bacterial meningitis. The mean age of subjects was 51 ± 47 months (range, 1-212 months). We performed the line probe assay in 751 (89%) CSF samples of 841 probable bacterial meningitis cases, of whom 431 (57%) were negative, 127 (17%) were positive for S. pneumoniae, 53 (7%) were positive for H. influenzae type b, and 41 (5%) were positive for N. meningitidis. The LPA was positive in 19 of 23 (82%) S. pneumoniae samples, 4 of 6 (67%) N. meningitidis samples and 2 of 2 (100%) Hib samples in CSF culture-positive cases. The specificity of the LPA for all of S. pneumoniae, H. influenzae type b, and N. meningitidis was 88% (95% CI: 85-91%), when using the standard PCR as a reference. The specificity of LPA for each of S. pneumoniae, H. influenzae type b, and N. meningitidis was 93% (95% CI: 89-95%), 96% (95% CI: 94-98%), and 99% (95% CI: 97-99%), respectively. For all of S. pneumoniae, H. influenzae type b and N. meningitidis the sensitivity of the LPA was 76% (95% CI: 70-82%) and for each of S. pneumoniae, H. influenzae type b and N. meningitidis was 72% (95% CI:63-79%), 88% (95% CI: 73-95%), and 81% (95% CI:67-92%), respectively. Conclusions: The LPA assay can be used to detect common bacterial meningitis pathogens in CSF samples, but the assay requires further improvement.

Wounds : a compendium of clinical research and practice, 2015

The rate of infection after a human bite is 10%-30%. Streptococcus spp. are the most common patho... more The rate of infection after a human bite is 10%-30%. Streptococcus spp. are the most common pathogens that may cause serious infections, such as necrotizing fasciitis. The authors describe a 5-year-old girl admitted to the emergency room with cellulitis due to S. pyogenes after human bites. She presented with fever and pain in her left arm, and her medical history revealed a human bite by her cousin on the arm 3 days prior. The wound culture yielded S. pyogenes. She was successfully treated with intravenous ampicillin-sulbactam regimen. S. pyogenes may cause serious wound infections following human bites. In such cases, the patient should be closely followed. Chemoprophylaxis should be initiated in an appropriate clinical setting to prevent secondary bacterial infections. This case was first reported as cellulitis due to S. pyogenes after a human bite.

Wounds : a compendium of clinical research and practice, 2016

Tuberculosis is a common problem in Turkey, and cutaneous tuberculosis is a rare form of extrapul... more Tuberculosis is a common problem in Turkey, and cutaneous tuberculosis is a rare form of extrapulmonary tuberculosis. Herein, the authors describe a case of cutaneous tuberculosis (lupus vulgaris) occurring after contact with a sheep. A 15-year-old boy was admitted to Marmara University School of Medicine Pendik Training and Research Hospital (Istanbul, Turkey) with delayed wound healing on the left index finger and left axillary lymphadenopathy. His medical history was unremarkable except for a wound incurred when he slaughtered a sheep 3 months before. One month after this injury, the patient developed enlargement of the left axillary lymph node on the side of the wounded extremity, and the wound turned a dark black color. The biopsy specimens obtained from the wounded skin and lymph nodes showed granulomatous reaction, but acid-fast bacilli (AFB) could not be shown with Ehrlich-Ziehl Neelsen staining. The patient tested positive in an interferon-gamma release assay. Computerized ...

Journal of Infection and Chemotherapy, 2016

The aim of the present study was to determine the diagnostic and prognostic values of suPAR and t... more The aim of the present study was to determine the diagnostic and prognostic values of suPAR and to compare them to CRP and PCT in pediatric patients with systemic inflammatory response syndrome (SIRS). A prospective case-control study was performed.The study was performed in a tertiary university hospital which has a 649-bed capacity. Patients included 27 children with SIRS and 27 control subjects without any infection or immunosuppressive condition. Blood samples were obtained on the day of admission and on the 4-7th days of the hospital stay. The median (min-max) serum levels of suPAR obtained on the first day of the admission were 10.06 (2.7-57.46) and 2.22 (1.08-5.13) ng/Ml for the SIRS group and control group, respectively. The median serum levels of suPAR in the SIRS group was significantly higher than that in the control group (p < 0.05). The serum suPAR levels was significantly higher in nonsurvivors than in survivors in SIRS group (p < 0.05). In the SIRS group, the area under the receiver operating characteristics curve (AUC(ROC)) for suPAR revealed an optimum cut-off value, sensitivity, specificity, NPV and PPV of 0.978, 3.8 ng/mL, 96%, 96%, 96%, and 96%, respectively. We conclude that suPAR does have diagnostic value in children with SIRS. Additionally, persistent high serum suPAR level predicts mortality in SIRS in children.

SpringerPlus, 2016

Background: Chryseobacterium indologenes is an uncommon organism that has been documented to caus... more Background: Chryseobacterium indologenes is an uncommon organism that has been documented to cause a variety of invasive infections mostly in hospitalized patients with severe underlying diseases. Case presentation: A three-month-old female infant born at term by caesarean section with meningomyelocele and congenital diaphragmatic hernia had two surgeries for the repair of meningomyelocele and diaphragmatic hernia on her 3rd and 14th day, respectively. On the 3rd month of her life, she deteriorated clinically with fever, leukocytosis and increase of acute-phase reactants. Gas exchange condition became worse than it was before. Respiratory secretions, oxygen requirements and ventilator demand increased. Chest X-ray showed bilateral pulmonary infiltrates. Bacteriological blood, urine and cerebrospinal fluid culture test results were negative. C. indologenes was isolated from tracheobronchial secretion sample obtained by endotracheal aspiration. Although susceptible to ciprofloxacin (MIC:0.5 gr/L), levofloxacin and piperacillin-tazobactam, the isolate was resistant to meropenem, imipenem and colistin. She was treated with ciprofloxacin successfully. Her fever resolved and gas exchange condition improved after 72 h of the treatment. The antibiotic treatment was given for a course of 14 days. Conclusion: Chryseobacterium indologenes may emerge as a potential pathogen in infants with the factors such as invasive equipment, having underlying diseases and prolonged hospitalization.

Case Reports in Infectious Diseases, 2016

Although voriconazole, a triazole antifungal, is a safe drug, treatment with this agent is associ... more Although voriconazole, a triazole antifungal, is a safe drug, treatment with this agent is associated with certain adverse events such as hepatic, neurologic, and visual disturbances. The current report presents two cases, one a 9-year-old boy and the other a 17-year-old girl, who experienced neurologic side effects associated with voriconazole therapy. Our aim is to remind readers of the side effects of voriconazole therapy in order to prevent unnecessary investigations especially for psychological and ophthalmologic problems. The first case was a 9-year-old boy with cystic fibrosis and invasive aspergillosis that developed photophobia, altered color sensation, and fearful visual hallucination. The second case was a 17-year-old girl with cystic fibrosis and allergic bronchopulmonary aspergillosis, and she experienced photophobia, fatigue, impaired concentration, and insomnia, when the dose of voriconazole therapy was increased from 12 mg/kg/day to 16 mg/kg/day. The complaints of th...

Journal of Clinical Immunology, 2016

Purpose-Loss and gain of function (GOF) mutations in human signal transducer and activator of tra... more Purpose-Loss and gain of function (GOF) mutations in human signal transducer and activator of transcription 1 (STAT1) lead to distinct phenotypes. Although recurrent infections are common to both types of STAT1 mutations, GOF mutations are distinguished by chronic mucocutaneous candidiasis and autoimmunity. However, the clinical spectra of STAT1 GOF mutations continue to expand. We here describe two patients with STAT1 GOF mutations presenting early in life with combined immunodeficiency (CID). Methods-Clinical data and laboratory findings including immunophenotyping, level of interferon (IFN)-γ/IL-17 + T cells, interferon-induced STAT1 phosphorylation and JAK inhibitor assays were evaluated. Sequencing of STAT1 gene was performed by Sanger sequencer. Results-Patient 1 (P1) had persistent oral candidiasis and cytomegalovirus (CMV) infection since 2 months of age, and later developed cavitary lung lesions due to Mycobacterium tuberculosis. Patient 2 (P2) presented with oral candidiasis and recurrent pneumonia at 4 months of age, and subsequently developed CMV pneumonitis. Both patients suffered heterozygous missense mutations in STAT1, leading to deleterious amino acid substitutions in the DNA binding domain (P1: c.1154C>T; p.T385M; P2. c.971G>T; p.C324F). Circulating CD4 + T cells of both patients exhibited increased interferon-γ and decreased IL-17 expression as compared to controls. They also exhibited increased IFN-β and-γ-induced STAT1 phosphorylation that was reversed upon treatment with the JAK kinase inhibitor Ruxolitinib.

Japanese Journal of Infectious Diseases, Jul 1, 2006

During a 6-month period, swab samples were obtained from the nares, axilla and perineum of 1,000 ... more During a 6-month period, swab samples were obtained from the nares, axilla and perineum of 1,000 children, age 0 to 16 years, who were attending a pediatric outpatient clinic. Staphylococcus aureus was isolated in 173 of the children. Only one child, a 35-day-old boy who had remained at the neonatal intensive care unit for 1 week after birth, was identified as a carrier of methicillin-resistant S. aureus. Except in diagnosed cases of allergic rhinitis, potential predisposing factors for colonization with S. aureus in our sample were comparable to those in non-colonized children.

Journal of Paediatrics and Child Health, Oct 1, 2008

Aim: A high rate (48.6%) of extended spectrum beta-lactamase production among Klebsiella pneumoni... more Aim: A high rate (48.6%) of extended spectrum beta-lactamase production among Klebsiella pneumoniae (ESBL-KP) clinical isolates in the paediatric wards of our hospital prompted the introduction of enhanced infection control measures, and after the implementation of these ...

A false-positive tuberculin skin test (TST) may be a result of T-cell sensitivity due to Bacille ... more A false-positive tuberculin skin test (TST) may be a result of T-cell sensitivity due to Bacille Calmette-Guérin (BCG) vaccination or exposure to non-tuberculous mycobacteria, thus leading to unnecessary isoniazid preventive therapy, especially in low-risk populations. Unlike TST, T-SPOT.TB is not confounded by BCG vaccination or exposure to most of the other non-tuberculous mycobacteria, because this assay is based on enumeration of interferon-secreting T cells in response to Mycobacterium tuberculosis-specific antigens. We compared the TST with T-SPOT.TB with respect to different TST cutoff points in healthy unexposed BCGvaccinated schoolchildren. A total of 209 children between 6 and 10 years of age with a TST induration of 0 (n = 50), 10-14 (n = 45), 15-19 (n = 95) and ≥20 mm (n = 19) were enrolled. Among TST-positive subjects, only 26 (23%) were positive with T-SPOT.TB, and T-SPOT.TB was positive in 4, 7, 20 and 42% of children with TST indurations of 0, 10-14, 15-19 and ≥20 mm, respectively. We suggest that confirmation of a positive TST by the interferon-based test would reduce unnecessary preventive therapy significantly in healthy unexposed BCGvaccinated children.

Vaccine, 2016

The 7-valent conjugate pneumococcal vaccine (PCV7) was introduced by the Turkey National Immuniza... more The 7-valent conjugate pneumococcal vaccine (PCV7) was introduced by the Turkey National Immunization Program in 2008 and replaced by the PCV13 in 2011. We assessed the impact of PCV vaccination on the nasopharyngeal (NP) carriage, serotype distribution and antimicrobial resistance of Streptococcus pneumoniae (SP) among healthy Turkish children. A prospective surveillance study was performed between September 2011 and September 2013 in Istanbul, Turkey. NP swabs, demographic data, and vaccination statuses were obtained from 2165 healthy children aged 0-18years. Pneumococcal carriage was defined by a positive culture; serotyping was performed via multiplex conventional PCR, and the antibiotic susceptibilities of the isolates were determined based on the minimum inhibitory concentration (MIC) values of the Clinical Laboratory Standards Institute (CLSI). The prevalence of pneumococcal carriage was 6.4%. The carriage rates were 8%, 7%, and 5% in the following age groups: 0-24months, 25-60months, and >60months, respectively. The carriage rate was significantly higher in the 0-24month age group than in the >60months age group (p=0.03). Sixty percent of the children were not vaccinated with any PCV; 4%, 2%, and 4% received at least 1, 2 or 3 doses and 30% children received the full schedule (4 doses) of either PCV7 or PCV13. Among the isolated S. pneumoniae strains, 45% were of the non-vaccine type (NVT) and 55% were of the vaccine type (VT). The children who received at least a single PCV dose had significantly lower odds of colonization via VT serotypes than the non-vaccinated children [odds ratio: 0.61 (95% confidence interval=0.41-0.91), p=0.01]. The percentages of the serotypes covered by PCV7 and PCV13 were 51% and 56%, respectively. The most frequently isolated serotypes were 6A/B/C (n=22, 16.5%), 19F (n=18, 13.5%), 23F (n=15, 11.2%), serotype 9V/A (n=10, 7.5%), 12F (n=5, 4.5%), 15A/F (n=7, 4.5%) and 22 A/F (n=6, 4.5%). Using the meningitis criteria and the MIC, 62% of the isolates were resistant to penicillin and 13% were non-sensitive to ceftriaxone. Erythromycin and clindamycin resistance were 43% and 31%, respectively. We shown that following nation-wide PCV vaccination, S. pneumoniae NP carriage was decreased.

Transplantation, Oct 1, 2001

Vancomycin-resistant enterococci (VRE) are increasingly important as pathogens in liver transplan... more Vancomycin-resistant enterococci (VRE) are increasingly important as pathogens in liver transplant patients. To guide control efforts, we conducted an epidemiological study of the frequency, source, and modes of transmission of VRE at our center. During September 1998 through August 1999, we obtained weekly surveillance cultures from consenting liver transplant patients and surfaces in their rooms. Pooled handwash specimens from personnel also were obtained. Specimens were processed on selective media to detect VRE, and isolates were typed by pulsed field gel electrophoresis. Information was collected from patient records concerning in-hospital treatment and clinical course. Serial cultures were obtained during 33 admissions of 29 patients. VRE were detected in initial specimens from 6 admissions, and nosocomial acquisition of VRE occurred in 12 (44%) of the remaining 27 admissions. Seven different strain types of VRE were detected. The initial site of acquisition was stool in all cases; bile became culture-positive in only two patients. Overall, 16 (55%) of the 29 patients became colonized, usually after transplantation. VRE were detected in environmental cultures during 10 admissions and in 2 of 21 pooled handwashes. No statistically significant differences in clinical status or treatment were found when colonized patients were compared to noncolonized controls. The only VRE infection resulted from a choledochojejunostomy anastomotic leak. Alimentary tract colonization by VRE occurred commonly in liver transplant patients, probably by cross-transmission. The clinical consequences were modest in the patients studied, but colonized transplant patients provide a substantial reservoir for continued VRE transmission in hospitals.

Mikrobiyol …, 2010

... Emel ALTUNCU1, Hülya BİLGEN1, Nilgün ÇERİKÇİOĞLU2, Arzu İLKİ2, Nurver ÜLGER2, Mustafa BAKIR3,... more ... Emel ALTUNCU1, Hülya BİLGEN1, Nilgün ÇERİKÇİOĞLU2, Arzu İLKİ2, Nurver ÜLGER2, Mustafa BAKIR3, İpek AKMAN1, Eren ÖZEK1 ... Hastaların demografik verileri, risk faktörleri, enfeksiyon odağı, enfeksiyona yol açan Candida türleri ile flukonazol (FKZ) ve amfoterisin B ...

Pediatric blood & …, 2006

We describe an 8-year-old boy who presented with multiple unresectable aspergillus brain abscesse... more We describe an 8-year-old boy who presented with multiple unresectable aspergillus brain abscesses as the initial presentation of X-linked chronic granulomatous disease (CGD). He failed initial therapy with amphotericin B, but was subsequently salvaged with voriconazole. CGD should be considered in the differential diagnosis for all children presenting with invasive fungal infections, particularly, those involving the central nervous system (CNS). Whereas, optimal pharmacologic therapy is still unknown for CNS aspergillosis, voriconazole may have an advantage due to its ability to cross the blood brain barrier and excellent oral absorption and bioavailability.

British journal of neurosurgery, Jan 28, 2018

Ventriculoperitoneal shunt (VPS) is the most common treatment modality for hydrocephalus. However... more Ventriculoperitoneal shunt (VPS) is the most common treatment modality for hydrocephalus. However, VPS infection is a common and serious complication with high rates of mortality and morbidity. The objective of this study was to investigate causative agents and the management of VPS infections and to identify risk factors for re-infection in children. Retrospective, multicentre study on patients with VPS infection at paediatric and neurosurgery departments in four tertiary medical centres in Turkey between January 2011 and September 2014. A total of 290 patients with VPS infections were identified during the study period. The aetiology of hydrocephalus was congenital malformations in 190 patients (65.5%). The most common symptom of shunt infection was fever in 108 (37.2%) cases. At least one pathogen was identified in 148 VPS infections (51%). The most commonly isolated pathogen was coagulase-negative staphylococci, which grew in 63 cases (42.5%), followed by Pseudomonas aeruginosa ...

The Pan African medical journal, 2016

Fungal infections like Paecilomyces keratitis have emerged in childhood recently. The diagnosis a... more Fungal infections like Paecilomyces keratitis have emerged in childhood recently. The diagnosis and treatment of Paecilomyces keratitis is difficult and the outcome is usually poor. Corneal culture should be performed on fungal media such as Sabouraud glucose neopeptone agar (SDA) as soon as possible for diagnosis. We report a rare case of Paecilomyces keratitis in an immunocompetent child, which was unresponsive to amphotericin B. The case was managed by a multidisciplinary approach involving the departments of ophthalmology, microbiology and pediatric infectious diseases. We want to draw attention once again that fungal keratitis caused by unusual agents are increasing. Physicians should consider fungal causes of keratitis, in patients with some predisposing factors like ocular surgery and prolonged use of topical corticosteroids.

Wounds : a compendium of clinical research and practice, 2016

Asian Pacific journal of allergy and immunology, Jan 12, 2016

Infections due to non-tuberculous mycobacteria species are problematic for immunodeficient indivi... more Infections due to non-tuberculous mycobacteria species are problematic for immunodeficient individuals. Mendelian susceptibility to mycobacterial diseases (MSMD) defines a group of genetic defects affecting cellular interactions and the interferon (IFN)-γ pathway. Patients with MSMD may present with a disseminated infection resulting from the Bacillus Calmette-Guerin vaccine, Mycobacterium tuberculosis complex, environmental nontuberculous mycobacteria or Salmonella species. Atypical mycobacterial infections and deficient granuloma or giant cell formation are important indicators for MSMD, especially in patients with a family history of parental consanguineous marriage. Herein we report the case of a boy with an IL-12Rβ1 defect who presented with massive intraabdominal lymphadenopathy due to Mycobacterium intracellulare infection. The patient was born to consanguineous parents, both heterozygous for the IL-12Rβ1 defect mutation. Debulking surgery was planned in order to decrease the...

Journal of Infection and Public Health, 2017

Raoultella planticola is rarely associated with clinical infection, and a limited number of pedia... more Raoultella planticola is rarely associated with clinical infection, and a limited number of pediatric cases have been reported. Herein we report a case of bacteremia presumptively secondary to bilateral conjunctivitis in an infant caused by R. planticola which was successfully treated with piperacillin-tazobactam. It should be kept in mind that R. planticola can be a pathogen in pediatric age groups.

Medical Mycology Case Reports, 2017

Although Saccharomyces boulardii is usually a non-pathogenic fungus, in rare occasions it can cau... more Although Saccharomyces boulardii is usually a non-pathogenic fungus, in rare occasions it can cause invasive infection in children. We present the case of an 8-year-old patient in pediatric surgical intensive care unit who developed S. cerevisiae fungemia following probiotic treatment containing S. boulardii. Caspofungin was not effective in this case and he was treated with amphotericin B. We want to emphasize that physicians should be careful about probiotic usage in critically ill patients.

BMC Microbiology, 2017

Background: The aim of this study is to compare the diagnostic performance of the line probe assa... more Background: The aim of this study is to compare the diagnostic performance of the line probe assay (LPA) with conventional multiplex polymerase chain reaction (PCR) for Streptococcus pneumoniae as well as real-time PCR for Neisseria meningitidis and Haemophilus influenzae type b (Hib) in cerebrospinal fluid (CSF) samples from children during the multicenter national surveillance of bacterial meningitis between the years 2006 and 2009 in Turkey. Results: During the study period 1460 subjects were enrolled and among them 841 (57%) met the criteria for probable bacterial meningitis. The mean age of subjects was 51 ± 47 months (range, 1-212 months). We performed the line probe assay in 751 (89%) CSF samples of 841 probable bacterial meningitis cases, of whom 431 (57%) were negative, 127 (17%) were positive for S. pneumoniae, 53 (7%) were positive for H. influenzae type b, and 41 (5%) were positive for N. meningitidis. The LPA was positive in 19 of 23 (82%) S. pneumoniae samples, 4 of 6 (67%) N. meningitidis samples and 2 of 2 (100%) Hib samples in CSF culture-positive cases. The specificity of the LPA for all of S. pneumoniae, H. influenzae type b, and N. meningitidis was 88% (95% CI: 85-91%), when using the standard PCR as a reference. The specificity of LPA for each of S. pneumoniae, H. influenzae type b, and N. meningitidis was 93% (95% CI: 89-95%), 96% (95% CI: 94-98%), and 99% (95% CI: 97-99%), respectively. For all of S. pneumoniae, H. influenzae type b and N. meningitidis the sensitivity of the LPA was 76% (95% CI: 70-82%) and for each of S. pneumoniae, H. influenzae type b and N. meningitidis was 72% (95% CI:63-79%), 88% (95% CI: 73-95%), and 81% (95% CI:67-92%), respectively. Conclusions: The LPA assay can be used to detect common bacterial meningitis pathogens in CSF samples, but the assay requires further improvement.

Wounds : a compendium of clinical research and practice, 2015

The rate of infection after a human bite is 10%-30%. Streptococcus spp. are the most common patho... more The rate of infection after a human bite is 10%-30%. Streptococcus spp. are the most common pathogens that may cause serious infections, such as necrotizing fasciitis. The authors describe a 5-year-old girl admitted to the emergency room with cellulitis due to S. pyogenes after human bites. She presented with fever and pain in her left arm, and her medical history revealed a human bite by her cousin on the arm 3 days prior. The wound culture yielded S. pyogenes. She was successfully treated with intravenous ampicillin-sulbactam regimen. S. pyogenes may cause serious wound infections following human bites. In such cases, the patient should be closely followed. Chemoprophylaxis should be initiated in an appropriate clinical setting to prevent secondary bacterial infections. This case was first reported as cellulitis due to S. pyogenes after a human bite.

Wounds : a compendium of clinical research and practice, 2016

Tuberculosis is a common problem in Turkey, and cutaneous tuberculosis is a rare form of extrapul... more Tuberculosis is a common problem in Turkey, and cutaneous tuberculosis is a rare form of extrapulmonary tuberculosis. Herein, the authors describe a case of cutaneous tuberculosis (lupus vulgaris) occurring after contact with a sheep. A 15-year-old boy was admitted to Marmara University School of Medicine Pendik Training and Research Hospital (Istanbul, Turkey) with delayed wound healing on the left index finger and left axillary lymphadenopathy. His medical history was unremarkable except for a wound incurred when he slaughtered a sheep 3 months before. One month after this injury, the patient developed enlargement of the left axillary lymph node on the side of the wounded extremity, and the wound turned a dark black color. The biopsy specimens obtained from the wounded skin and lymph nodes showed granulomatous reaction, but acid-fast bacilli (AFB) could not be shown with Ehrlich-Ziehl Neelsen staining. The patient tested positive in an interferon-gamma release assay. Computerized ...

Journal of Infection and Chemotherapy, 2016

The aim of the present study was to determine the diagnostic and prognostic values of suPAR and t... more The aim of the present study was to determine the diagnostic and prognostic values of suPAR and to compare them to CRP and PCT in pediatric patients with systemic inflammatory response syndrome (SIRS). A prospective case-control study was performed.The study was performed in a tertiary university hospital which has a 649-bed capacity. Patients included 27 children with SIRS and 27 control subjects without any infection or immunosuppressive condition. Blood samples were obtained on the day of admission and on the 4-7th days of the hospital stay. The median (min-max) serum levels of suPAR obtained on the first day of the admission were 10.06 (2.7-57.46) and 2.22 (1.08-5.13) ng/Ml for the SIRS group and control group, respectively. The median serum levels of suPAR in the SIRS group was significantly higher than that in the control group (p < 0.05). The serum suPAR levels was significantly higher in nonsurvivors than in survivors in SIRS group (p < 0.05). In the SIRS group, the area under the receiver operating characteristics curve (AUC(ROC)) for suPAR revealed an optimum cut-off value, sensitivity, specificity, NPV and PPV of 0.978, 3.8 ng/mL, 96%, 96%, 96%, and 96%, respectively. We conclude that suPAR does have diagnostic value in children with SIRS. Additionally, persistent high serum suPAR level predicts mortality in SIRS in children.

SpringerPlus, 2016

Background: Chryseobacterium indologenes is an uncommon organism that has been documented to caus... more Background: Chryseobacterium indologenes is an uncommon organism that has been documented to cause a variety of invasive infections mostly in hospitalized patients with severe underlying diseases. Case presentation: A three-month-old female infant born at term by caesarean section with meningomyelocele and congenital diaphragmatic hernia had two surgeries for the repair of meningomyelocele and diaphragmatic hernia on her 3rd and 14th day, respectively. On the 3rd month of her life, she deteriorated clinically with fever, leukocytosis and increase of acute-phase reactants. Gas exchange condition became worse than it was before. Respiratory secretions, oxygen requirements and ventilator demand increased. Chest X-ray showed bilateral pulmonary infiltrates. Bacteriological blood, urine and cerebrospinal fluid culture test results were negative. C. indologenes was isolated from tracheobronchial secretion sample obtained by endotracheal aspiration. Although susceptible to ciprofloxacin (MIC:0.5 gr/L), levofloxacin and piperacillin-tazobactam, the isolate was resistant to meropenem, imipenem and colistin. She was treated with ciprofloxacin successfully. Her fever resolved and gas exchange condition improved after 72 h of the treatment. The antibiotic treatment was given for a course of 14 days. Conclusion: Chryseobacterium indologenes may emerge as a potential pathogen in infants with the factors such as invasive equipment, having underlying diseases and prolonged hospitalization.

Case Reports in Infectious Diseases, 2016

Although voriconazole, a triazole antifungal, is a safe drug, treatment with this agent is associ... more Although voriconazole, a triazole antifungal, is a safe drug, treatment with this agent is associated with certain adverse events such as hepatic, neurologic, and visual disturbances. The current report presents two cases, one a 9-year-old boy and the other a 17-year-old girl, who experienced neurologic side effects associated with voriconazole therapy. Our aim is to remind readers of the side effects of voriconazole therapy in order to prevent unnecessary investigations especially for psychological and ophthalmologic problems. The first case was a 9-year-old boy with cystic fibrosis and invasive aspergillosis that developed photophobia, altered color sensation, and fearful visual hallucination. The second case was a 17-year-old girl with cystic fibrosis and allergic bronchopulmonary aspergillosis, and she experienced photophobia, fatigue, impaired concentration, and insomnia, when the dose of voriconazole therapy was increased from 12 mg/kg/day to 16 mg/kg/day. The complaints of th...

Journal of Clinical Immunology, 2016

Purpose-Loss and gain of function (GOF) mutations in human signal transducer and activator of tra... more Purpose-Loss and gain of function (GOF) mutations in human signal transducer and activator of transcription 1 (STAT1) lead to distinct phenotypes. Although recurrent infections are common to both types of STAT1 mutations, GOF mutations are distinguished by chronic mucocutaneous candidiasis and autoimmunity. However, the clinical spectra of STAT1 GOF mutations continue to expand. We here describe two patients with STAT1 GOF mutations presenting early in life with combined immunodeficiency (CID). Methods-Clinical data and laboratory findings including immunophenotyping, level of interferon (IFN)-γ/IL-17 + T cells, interferon-induced STAT1 phosphorylation and JAK inhibitor assays were evaluated. Sequencing of STAT1 gene was performed by Sanger sequencer. Results-Patient 1 (P1) had persistent oral candidiasis and cytomegalovirus (CMV) infection since 2 months of age, and later developed cavitary lung lesions due to Mycobacterium tuberculosis. Patient 2 (P2) presented with oral candidiasis and recurrent pneumonia at 4 months of age, and subsequently developed CMV pneumonitis. Both patients suffered heterozygous missense mutations in STAT1, leading to deleterious amino acid substitutions in the DNA binding domain (P1: c.1154C>T; p.T385M; P2. c.971G>T; p.C324F). Circulating CD4 + T cells of both patients exhibited increased interferon-γ and decreased IL-17 expression as compared to controls. They also exhibited increased IFN-β and-γ-induced STAT1 phosphorylation that was reversed upon treatment with the JAK kinase inhibitor Ruxolitinib.

Japanese Journal of Infectious Diseases, Jul 1, 2006

During a 6-month period, swab samples were obtained from the nares, axilla and perineum of 1,000 ... more During a 6-month period, swab samples were obtained from the nares, axilla and perineum of 1,000 children, age 0 to 16 years, who were attending a pediatric outpatient clinic. Staphylococcus aureus was isolated in 173 of the children. Only one child, a 35-day-old boy who had remained at the neonatal intensive care unit for 1 week after birth, was identified as a carrier of methicillin-resistant S. aureus. Except in diagnosed cases of allergic rhinitis, potential predisposing factors for colonization with S. aureus in our sample were comparable to those in non-colonized children.

Journal of Paediatrics and Child Health, Oct 1, 2008

Aim: A high rate (48.6%) of extended spectrum beta-lactamase production among Klebsiella pneumoni... more Aim: A high rate (48.6%) of extended spectrum beta-lactamase production among Klebsiella pneumoniae (ESBL-KP) clinical isolates in the paediatric wards of our hospital prompted the introduction of enhanced infection control measures, and after the implementation of these ...

A false-positive tuberculin skin test (TST) may be a result of T-cell sensitivity due to Bacille ... more A false-positive tuberculin skin test (TST) may be a result of T-cell sensitivity due to Bacille Calmette-Guérin (BCG) vaccination or exposure to non-tuberculous mycobacteria, thus leading to unnecessary isoniazid preventive therapy, especially in low-risk populations. Unlike TST, T-SPOT.TB is not confounded by BCG vaccination or exposure to most of the other non-tuberculous mycobacteria, because this assay is based on enumeration of interferon-secreting T cells in response to Mycobacterium tuberculosis-specific antigens. We compared the TST with T-SPOT.TB with respect to different TST cutoff points in healthy unexposed BCGvaccinated schoolchildren. A total of 209 children between 6 and 10 years of age with a TST induration of 0 (n = 50), 10-14 (n = 45), 15-19 (n = 95) and ≥20 mm (n = 19) were enrolled. Among TST-positive subjects, only 26 (23%) were positive with T-SPOT.TB, and T-SPOT.TB was positive in 4, 7, 20 and 42% of children with TST indurations of 0, 10-14, 15-19 and ≥20 mm, respectively. We suggest that confirmation of a positive TST by the interferon-based test would reduce unnecessary preventive therapy significantly in healthy unexposed BCGvaccinated children.

Vaccine, 2016

The 7-valent conjugate pneumococcal vaccine (PCV7) was introduced by the Turkey National Immuniza... more The 7-valent conjugate pneumococcal vaccine (PCV7) was introduced by the Turkey National Immunization Program in 2008 and replaced by the PCV13 in 2011. We assessed the impact of PCV vaccination on the nasopharyngeal (NP) carriage, serotype distribution and antimicrobial resistance of Streptococcus pneumoniae (SP) among healthy Turkish children. A prospective surveillance study was performed between September 2011 and September 2013 in Istanbul, Turkey. NP swabs, demographic data, and vaccination statuses were obtained from 2165 healthy children aged 0-18years. Pneumococcal carriage was defined by a positive culture; serotyping was performed via multiplex conventional PCR, and the antibiotic susceptibilities of the isolates were determined based on the minimum inhibitory concentration (MIC) values of the Clinical Laboratory Standards Institute (CLSI). The prevalence of pneumococcal carriage was 6.4%. The carriage rates were 8%, 7%, and 5% in the following age groups: 0-24months, 25-60months, and >60months, respectively. The carriage rate was significantly higher in the 0-24month age group than in the >60months age group (p=0.03). Sixty percent of the children were not vaccinated with any PCV; 4%, 2%, and 4% received at least 1, 2 or 3 doses and 30% children received the full schedule (4 doses) of either PCV7 or PCV13. Among the isolated S. pneumoniae strains, 45% were of the non-vaccine type (NVT) and 55% were of the vaccine type (VT). The children who received at least a single PCV dose had significantly lower odds of colonization via VT serotypes than the non-vaccinated children [odds ratio: 0.61 (95% confidence interval=0.41-0.91), p=0.01]. The percentages of the serotypes covered by PCV7 and PCV13 were 51% and 56%, respectively. The most frequently isolated serotypes were 6A/B/C (n=22, 16.5%), 19F (n=18, 13.5%), 23F (n=15, 11.2%), serotype 9V/A (n=10, 7.5%), 12F (n=5, 4.5%), 15A/F (n=7, 4.5%) and 22 A/F (n=6, 4.5%). Using the meningitis criteria and the MIC, 62% of the isolates were resistant to penicillin and 13% were non-sensitive to ceftriaxone. Erythromycin and clindamycin resistance were 43% and 31%, respectively. We shown that following nation-wide PCV vaccination, S. pneumoniae NP carriage was decreased.

Transplantation, Oct 1, 2001

Vancomycin-resistant enterococci (VRE) are increasingly important as pathogens in liver transplan... more Vancomycin-resistant enterococci (VRE) are increasingly important as pathogens in liver transplant patients. To guide control efforts, we conducted an epidemiological study of the frequency, source, and modes of transmission of VRE at our center. During September 1998 through August 1999, we obtained weekly surveillance cultures from consenting liver transplant patients and surfaces in their rooms. Pooled handwash specimens from personnel also were obtained. Specimens were processed on selective media to detect VRE, and isolates were typed by pulsed field gel electrophoresis. Information was collected from patient records concerning in-hospital treatment and clinical course. Serial cultures were obtained during 33 admissions of 29 patients. VRE were detected in initial specimens from 6 admissions, and nosocomial acquisition of VRE occurred in 12 (44%) of the remaining 27 admissions. Seven different strain types of VRE were detected. The initial site of acquisition was stool in all cases; bile became culture-positive in only two patients. Overall, 16 (55%) of the 29 patients became colonized, usually after transplantation. VRE were detected in environmental cultures during 10 admissions and in 2 of 21 pooled handwashes. No statistically significant differences in clinical status or treatment were found when colonized patients were compared to noncolonized controls. The only VRE infection resulted from a choledochojejunostomy anastomotic leak. Alimentary tract colonization by VRE occurred commonly in liver transplant patients, probably by cross-transmission. The clinical consequences were modest in the patients studied, but colonized transplant patients provide a substantial reservoir for continued VRE transmission in hospitals.