ABSTRACT
Actinotignum schaalii (formerly known as Actinobaculum schaalii) is an anaerobic or facultative anaerobic gram-positive bacillus that can be found commensally in the urogenital region. It can be overlooked because it grows slowly and is difficult to identify with classical microbiology laboratory techniques. Colonies become visible after 48-72 hours of incubation on blood agar in anaerobic or CO2-rich media. While it typically causes urinary tract infection in older individuals, cases of bacteremia, vertebral osteomyelitis, endocarditis and cellulitis have been reported. Fournier's gangrene caused by A.schaalii has been reported very rarely so far. Fournier's gangrene has been defined as necrotizing fasciitis of the external genitalia, perineal and perianal region. Diabetes, immunosuppression, peripheral vascular disease, urethral anomalies, chronic alcoholism and smoking are important predisposing factors. In addition, approximately 25% of the cases have no known or identifiable etiology. The bacteria causing the infection may originate from skin, urogenital or intestinal microbiota. In this case report, a new case of Fournier's gangrene caused by A.schaalii was presented. A 65-year-old male patient admitted to the emergency department with the complaints of pain, swelling, redness in the left testis and also nausea, vomiting and chills that started three days ago. Physical examination revealed increased diameter of the scrotum, intense hyperemia of the skin and foci of necrosis. It was learned that the patient had no known chronic disease other than benign prostatic hyperplasia. The patient reported smoking of 25 packs of cigarettes per year. Routine laboratory tests revealed leukocyte= 32.41 x 109/L, neutrophil= 89.9%, procalcitonin= 1.62 ug/L, CRP= 265.07 mg/L and the patient was operated with the diagnosis of Fournier's gangrene. Gram staining of the abscess specimen obtained during the operation showed gram-positive bacilli both inside and outside the leukocytes. After 24 hours, grampositive bacilli were detected in the Gram staining of thin, transparent/gray colonies grown on 5% sheep blood and chocolate agar. The isolate was identified as A.schaalii by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) VITEK® MS (bioMérieux, France) microbial identification system. VITEK®2 ID ANC (bioMérieux, France) bacterial identification card was also used for comparison but the bacteria could be identified. As a result of the sequence analysis performed for confirmation, it was shown to be 100% homologous with Actinobaculum schaalii (GenBank accession no: FJ711193.1). For susceptibility tests, 5% sheep blood Schaedler agar was used and incubated in anaerobic environment. According to the minimal inhibitory concentration (MIC) results evaluated after 48 hours, penicillin was found to be 0.032 mg/L, clindamycin 0.125 mg/L, ciprofloxacin 0.19 mg/L, ceftazidime 4 mg/L, and amoxicillin 0.19 mg/L. The primary cause that initiated the infection in the case could not be identified, but it was thought that the presence of prostatic hyperplasia and smoking history may have contributed to the occurence or the progress of the disease. It is noteworthy that the ciprofloxacin MIC result was quite low compared to other studies. In addition, this study revealed the value of MALDI-TOF MS based methods in identification. In conclusion, it is thought that a significant proportion of A.schaalii infections may be overlooked due to the difficulty in growth and identification. Increasing the diagnostic power of clinical microbiology laboratories for poorly identified bacteria and renewing the databases of commercial identification systems are important for the early and accurate diagnosis and treatment of serious infections that may occur with such agents.
Subject(s)
Actinomycetaceae , Fournier Gangrene , Male , Humans , Animals , Sheep , Aged , Agar , Bacteria, Anaerobic , CiprofloxacinABSTRACT
OBJECTIVES: Hepatitis C virus (HCV), which has no protective vaccine, is a common cause of chronic hepatitis, which is a severe public health threat. There are differences in nucleotide and amino acid sequences in different regions of the HCV genome. As a result of these differences, HCV has been shown to have at least seven major genotypes and many subtypes. In Turkey, the prevalence of genotype 1 is between 51.7% and 97.1%, the highest rate among all genotypes, while subtype 1b is the genotype with the highest rate. It is important to detect mixed genotype infection reliably as it causes treatment failure. This study aims to reveal the distribution of the HCV genotypes in our hospital in Istanbul over the years and to contribute to the epidemiological data of Turkey. METHODS: For this purpose, 385 patient samples sent to Sisli Hamidiye Etfal Training and Research Hospital, Clinical Microbiology Laboratory for HCV genotype determination between January 2016 and June 2019 were evaluated retrospectively. Anti-HCV was screened by enzyme immunoassay and confirmation was performed by Line immunoassay. HCV genotyping assays targeting highly conserved 5'UTR and most variable region NS5B regions were used. RESULTS: The most common genotype was genotype 1 (81.3%) with 313 cases and subtypes 1a and 1b were detected at the rates of 10.9% and 67.8%, respectively. In addition, genotype 3, 2, 4, 5 were detected at the rates of 8.8%, 3.4%, 2.9%, 0.8%, respectively and mixed genotype was found in 2.9% of cases. Although genotype 5 is seen in South Africa, it is found in the Middle East region, albeit at a low rate. In our study, it was observed that genotype 5 was detected in different years from patients of Syrian origin. CONCLUSION: In this study, genotype 1 was the most common genotype with a rate of 81.3% and subtype 1b was 67.8%, in accordance with the literature. However, genotypes 3, 2, 4 and 5 were also present at low rates. It is important to monitor these rare genotypes since some of them are dominant in surrounding countries. In addition, 2.9% of HCV mixed genotype was detected and this should be considered concerning management of HCV infection.
ABSTRACT
OBJECTIVES: Healthcare-associated infections (HCAI), which are important causes of mortality and morbidity, are high cost but preventable infections. This study aimed to determine hospital infections and isolates in Sisli Hamidiye Etfal Training and Hospital and to determine our local data. The changes in the distribution of the isolates in this process were evaluated by comparing the data of 1995 and today. METHODS: Materials sent to the microbiology laboratory of our hospital in 1995 and 2017 from the patients hospitalized in the period between June 1-December 31 were evaluated concerning hospital infection. The standard manual methods were used in 1995, while in 2017, MALDI-TOF MS was used for identification and BD Phoenix automated system for antibiotic susceptibility. RESULTS: In 1995, in total, 100 bacteria were isolated from pediatric and adult patients, of which 48 Pseudomonas aeruginosa (48/100), 37 Klebsiella spp (37/100). In 2017, Acinetobacter baumannii causing an important resistance problem was found to be increased in number. The main hospital infection causes were Acinetobacter baumannii (37/179), Klebsiella spp (41/179). In 2017, bacterial diversity was also increased. CONCLUSION: Isolated strains, as in the past, are gram-negative bacteria, Pseudomonas spp decreased in 2017, and Acinetobacter spp increased. The findings suggest that the automated systems used in microbiology laboratories may have a role in the detection of bacterial diversity.
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OBJECTIVES: Extended-spectrum beta-lactamases (ESBLs) have been detected more frequently in members of the Enterobacteriaceae family, particularly Escherichia coli and Klebsiella pneumoniae. Infections caused by ESBL-producing bacteria are often resistant to treatment with various antibiotic classes and accompanied by increased complication risks, mortality, and costs. In this study, blood culture results were analyzed to determine the change in the ESBL production rate and antibiotic susceptibilities in E. coli and K. pneumoniae isolates over a period of 3 years. METHODS: The results of blood cultures sent to our laboratory between February 2014 and August 2016 were examined retrospectively. Repeat isolates from the same patient were not included when antibiotic susceptibility rates and clinical distributions were calculated. BD Bactec FX automated blood culture system (Becton Dickinson, Sparks, MD, USA) was used to examine the blood cultures. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (Bruker Daltonics, Bremen, Germany) was used to identify microorganisms. For antibiotic susceptibility tests (AST) and ESBL detection Kirby Bauer disk diffusion method or Phoenix automated system (Becton Dickinson, Sparks, MA, USA) was used. When the AST results were evaluated, Clinical and Laboratory Standards Institute breakpoints were used for 2014 and 2015, and European Committee on Antimicrobial Susceptibility Testing breakpoints were used for 2016. RESULTS: During the 3-year period, 224 (35%) of 632 E. coli and 137 (31%) of 439 K. pneumoniae isolates were determined to be ES BL-producers. The ESBL-positive isolate percentage for E. coli and K. pneumoniae for 2014, 2015, and 2016 was 23%, 36%, 48% and 23%, 32%, 37%, respectively. The increase in ESBL was statistically significant for both E. coli (p<0.001) and K. pneumoniae (p=0.011). ESBL-positive E. coli and K. pneumoniae strains were most sensitive to carbapenem-class antibiotics, amikacin, and colistin. While there was no meropenem-resistant strain, 5 (3.3%) ertapenem-resistant and 1 (0.7%) imipenem-resistant ESBL E. coli strains were detected. The ESBL K. pneumoniae strain resistance rate to ertapenem, imipenem, and meropenem was 12%, 11.2%, and 11.1%, respectively. The resistance rates of K. pneumonia strains to ertapenem, imipenem, meropenem, and piperacillin-tazobactam increased significantly over the study period (p<0.001). CONCLUSION: Monitoring ESBL rates and the antibiotic susceptibility of E. coli and K. pneumoniae strains of bloodstream infections is of the utmost importance in guiding empiric antibiotic therapies and patient management.
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OBJECTIVE: It has been shown in previous studies that inadequate empirical treatment is associated with mortality in a variety of infections caused by Gram-negative bacteria. In this study, the clinical effect of discordance in empirical treatment was investigated in patients with urinary tract infection (UTI) accompanied by bacteremia. MATERIAL AND METHODS: We retrospectively reviewed the files of adult (>18 years old) patients who were diagnosed with UTI in our clinic between January 2014 and December 2015. Cases in which the same causative microorganism grew in both blood and urine cultures were included in the study. Patients using ceftriaxone and carbapenem as empirical antibiotic therapy (EAT) were compared as two different groups. In cases that the ethiologic agents were extended- spectrum beta lactamase (ESBL)-producing Klebsiella pneumoniae and Escherichia coli isolates, if the microorganism was resistant to initial antibiotic treatment the situation was defined as EAT discordance, and if it was sensitive it was defined as EAT concordance. RESULTS: After the exclusion criteria were applied, 65 of the 266 cases examined were taken into the study. Clinical and laboratory features of cases of ceftriaxone and carbapenem groups were similar. There was no statistically significant difference between the two groups in terms of hospital stay and survival (p>0.05). Of 28 cases of ESBL-producing E. coli and K. pneumoniae, 18 were EAT discordant and 10 were EAT concordant. Clinical and laboratory features of EAT concordant and EAT discordant groups were similar. No statistically significant difference was found between the two groups in terms of hospital stay and survival (p>0.05). CONCLUSION: It was considered that ceftriaxone can still be a viable option in the EAT of UTI, which is accompanied by bacteremia without severe sepsis and septic shock findings. It was concluded that EAT discordance may not have a negative effect on the duration of hospital stay and survival rates in neither total cases nor ESBL positive ones.
ABSTRACT
Pharyngitis in most cases is due to viral microorganisms however drug therapy without the detection of etiological agent leads to unnecessary use of antibiotics. On the other hand, when the etiologic agent is group A beta-hemolytic streptococci (GAS) it is important to identify the etiologic agent rapidly which will guide the treatment with appropriate antibiotics. The use of highly sensitive rapid tests will contribute significantly to early diagnosis and appropriate therapy. The aim of this study is to evaluate the efficacy of Mascia Brunelli rapid antigen test for the detection of GAS in throat swab samples. A total of 833 throat swab samples submitted to our laboratory with pre-diagnosis of pharyngitis were assessed between June 2016 and August 2016. The samples were simultaneously cultured and tested by rapid Mascia Brunelli Strep-A Card (Mascia Brunelli S.p.a, Italy). For identification, bacitracin sensitivity, PYR test and latex agglutination test in addition to Bruker MALDI-TOF MS (Daltonics, Germany) system were used. The density of GAS growth in the culture was noted. The samples that were false negative with Mascia Brunelli test were re-tested with QuickVue + Strep A Test (Quidel Corporation, San Diego, USA) rapid antigen test. A total of 833 patients, 376 (45.2%) female and 457 (54.8%) male were included in the study. The age range was between 0-94 years with a mean value of 7.86 ± 6.72. 125 (15%) and 94 (11.28%) of the samples were positive with culture and rapid antigen test, respectively. Mascia Brunelli antigen test gave negative results for 31 culture positive samples. Of these 31 samples, 28 were found positive by QuickVue + Strep A antigen test. As a result, the sensitivity of the test was found to be independent of the inoculum effect. The culture positivity rate in patients between 5-15 years was 18.4%. The sensitivity, specificity, positive predictive value, negative predictive value and the accuracy of Mascia Brunelli antigen test, with respect to culture, were 75.2%, 100%, 100%, 95.81% and 96.28%, respectively. In conclusion, the selection of rapid antigen tests with high sensitivity in the diagnosis of GAS pharyngitis will contribute to the prevention of resistance development by appropriate use of antibiotics as well as early diagnosis and appropriate treatment. However, confirmation of negative rapid antigen test results by culture is very important in terms of false diagnosis and prevention of incomplete treatment.
Subject(s)
Antigens, Bacterial/analysis , Pharyngitis/diagnosis , Streptococcal Infections/diagnosis , Streptococcus pyogenes/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Pharyngitis/drug therapy , Pharyngitis/microbiology , Pharynx/microbiology , Predictive Value of Tests , Sensitivity and Specificity , Streptococcal Infections/drug therapy , Streptococcal Infections/microbiology , Streptococcus pyogenes/isolation & purification , Young AdultABSTRACT
Timely detection of carbapenemases by both phenotypic and genotypic methods is essential for developing strategies to control the spread of infections by carbapenem-resistant isolates and related morbidity and mortality. The aim of this study was to compare the performance of a commercial kit, the RAPIDEC® CARBA NP, and an in-house technique, the carbapenem inactivation method (CIM), against a panel of 136 carbapenemase- and noncarbapenemase-producing Enterobacteriaceae, Acinetobacter baumannii, and Pseudomonas aeruginosa isolates. RAPIDEC CARBA NP displayed 99% sensitivity and 100% specificity, whereas the sensitivity and specificity were 78% and 100% for the CIM test, respectively. A slight modification of the CIM test, a prolonged incubation time of 4 hours instead of two, increased the sensitivity of the test to 90% by diminishing false negativity particularly for A. baumannii. In conclusion, both tests possess a high performance and are practical for the detection of carbapenemases. Although RAPIDEC CARBA NP is a more rapid and reliable method, the CIM test may represent a useful tool for microbiology laboratories due to its simplicity and availability at any laboratory with low cost.
Subject(s)
Anti-Bacterial Agents/metabolism , Bacterial Proteins/analysis , Enterobacteriaceae/enzymology , Reagent Kits, Diagnostic/standards , Thienamycins/metabolism , beta-Lactamases/analysis , Acinetobacter baumannii/drug effects , Acinetobacter baumannii/enzymology , Acinetobacter baumannii/genetics , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Enterobacteriaceae/drug effects , Enterobacteriaceae/genetics , Gene Expression , Inactivation, Metabolic , Meropenem , Microbial Sensitivity Tests , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/enzymology , Pseudomonas aeruginosa/genetics , Sensitivity and Specificity , Thienamycins/pharmacology , beta-Lactamases/genetics , beta-Lactamases/metabolismABSTRACT
Worldwide increase in carbapenem resistance and transferable carbapenemases are significant challenges in treatment of Pseudomonas aeruginosa infections. In this study, investigation of carbapenemase production in carbapenem-resistant P. aeruginosa isolates recovered from clinical specimens in a tertiary hospital was aimed. A total of 84 carbapenem-resistant P. aeruginosa isolates were examined. "Carbapenem inactivation method" (CIM) was used for phenotypic detection of carbapenemase production. The existence of blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-48, and blaGES genes was investigated by polymerase chain reaction (PCR). Subtypes of the detected genes were identified by sequence analysis. Arbitrarily primed PCR (AP-PCR) was performed to evaluate the clonal relationship among the isolates. The presence of high-risk clones in carbapenemase producers was investigated by Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). Three isolates (3.5%) were identified as carbapenemase producers by CIM tests, while PCR tests demonstrated three isolates carrying carbapenemase genes as well. blaVIM gene was found in two isolates and blaGES gene was found in one isolate. Sequence analysis demonstrated that the carbapenemases were VIM-1, VIM-2, and GES-5. AP-PCR yielded high clonal diversity among the isolates. According to MALDI-TOF MS analysis, none of the carbapenemase-producing strains belonged to the high-risk clones. In conclusion, the presence of VIM-1, VIM-2, and GES-5 type carbapenemases in P. aeruginosa isolates was demonstrated for the first time in our hospital, GES-5 being reported for the second time in Turkey. Our results will lead strategies for controlling the spread of carbapenemases and contribute to epidemiological data from Turkey.
Subject(s)
Bacterial Proteins/genetics , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/isolation & purification , beta-Lactamases/genetics , Anti-Bacterial Agents/pharmacology , Carbapenems/pharmacology , DNA, Bacterial/genetics , Humans , Microbial Sensitivity Tests/methods , Multilocus Sequence Typing/methods , Pseudomonas Infections/drug therapy , Pseudomonas Infections/microbiology , Tertiary Care Centers , TurkeyABSTRACT
Nondiphtherial Corynebacterium species isolated from clinical specimens are usually considered as contaminants by many clinicians when reported by microbiologists. However, an increasing number of studies have confirmed the importance of Corynebacterium spp. in the etiology of a variety of infectious processes. In this report, we present a case of bronchopneumonia caused by Corynebacterium propinquum. The infection occurred in a seven-year-old child who had a history of immunosuppression due to ataxia telangiectasia. The purulent sputum of the patient yielded a large number of polymorphonuclear leucocytes with abundant gram-positive coryneform bacilli in gram staining and pure growth of coryneform bacteria in culture. Definitive identification as C. propinquum was made by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequencing. C. propinquum should be recognized as a potential pathogen and included in the etiologic diagnostic algorithm, particularly in patients with immunosuppressive conditions.