High prevalence of class 1 integrons in clinical isolates of methicillin-resistant Staphylococcus aureus from India

Introduction: Class1 integrons are one of the prevalent mechanisms of antibiotic resistance gene transfer in Gram-negative organisms, but their prevalence and role in the spread of antibiotic resistance genes in methicillin-resistant Staphylococcus aureus (MRSA) is unexplored. The purpose of this study was to investigate the prevalence of class 1 integrons in clinical isolates of MRSA. Materials and Methods: Total 143 MRSA isolates obtained from two different cities in India (Pune and Mumbai) were characterized by biochemical tests, and the antibiotic sensitivity was performed using the Clinical and Laboratory Standards Institute (CLSI) guidelines. The presence of class 1 integrons, sul1/qacEΔ1 region of class 1 integron and mecA gene among these isolates was determined by polymerase chain reaction (PCR). Results: All 143 isolates were mecA positive and coagulase-positive. Overall, 71% of the MRSA isolates carried class 1 integrons; 58% (45/77) of the isolates obtained from Mumbai and 85% (56/66) of the isolates from Pune carried class 1 integrons. In all, 39% of these isolates carried sul1/qacEΔ1 region, thus confirming the association of class 1 integrons with antibiotic resistance genes. Along with β-lactam antibiotics the MRSA isolates were resistant to several other antibiotics, with resistance to erythromycin, ciprofloxacin and trimethoprim-sulfamethoxazole being observed in 75%, 66% and 60% of the isolates, respectively. Conclusion: To the best of our knowledge, this is the first report of class 1 integrons in MRSA isolates from India. The study provides insights into the prevalence of a novel mechanism adapted by MRSA for the propagation of antibiotic resistance genes.     

Microbiological Profile of Infections of the Hip Joint: An Indian Perspective

Background: Knowledge of the local microbiological epidemiology helps in formulating protocols for appropriate treatment of hip infections. The aim of this study was to profile the organisms cultured from infected hips. Methods: The microbiological profile and sensitivity pattern of organisms in eighty infected hips were reviewed. Results: Infection was secondary to arthroplasty in 35, fracture surgery in 34 and primary septic arthritis in 11. Twenty percent of the infections were polymicrobial, whereas the rest were monomicrobial. Fifty-five percent were Gram-positive, of which 45% were Staphylococcus species (36% methicillin-sensitive Staphylococcus aureus, 20% methicillin-resistant S. aureus, and 44% coagulase sensitive Staphylococcal species). All Staphylococcus species were sensitive to vancomycin, but 20% of Enterococcus species were resistant to vancomycin. One-third of the Enterococcus species and 2% of Staphylococcus species were resistant to teicoplanin. Escherichia coli (n = 10) and Pseudomonas sp. (n = 13) were the most common Gram-negative organism. Although 18% of the Gram-negative organisms were carbapenem resistant, all were sensitive to colistin. Conclusion: Staphylococcus sp. was the most common pathogen found in hip infections. However, the high incidence of Gram-negative infection requires that prophylactic antibiotics cover these organisms as well. The high resistance to first-line antibiotics should be taken into consideration while making protocols. The knowledge of the microbial profile is especially important when considering arthroplasty for arthritis secondary to hip infections.     

Validation of EUCAST zone diameter breakpoints against reference broth microdilution

The European Committee on Antimicrobial Susceptibility Testing (EUCAST) began harmonizing clinical breakpoints in Europe 2002. In 2009, work to develop a disc diffusion method began and the first disc diffusion breakpoints calibrated to EUCAST clinical MIC breakpoints were published in December 2009. In this study we validated EUCAST clinical zone diameter breakpoints against the International Standard Organization (ISO) reference broth microdilution. A collection of 544 isolates (238 Gram-negative and 306 Gram-positive) were tested against a panel of antimicrobial agents. Antimicrobial susceptibility testing was performed with broth microdilution as described by ISO and disc diffusion in accordance with EUCAST methodology. Inhibition zone diameters and MIC values were interpreted and categorized (S, I and R) according to EUCAST clinical breakpoint table version 2.0. Categorical agreement (CA) as well as minor (mD), major (MD) and very major (VMD) discrepancies were determined. There was in general good correlation between susceptibility test results obtained with disc diffusion and broth microdilution. Overall CA was 97.3% for all combinations of organisms and antimicrobial agents (<n = 5231) and the overall discrepancy rates were 110 (2.1%) mD, 24 (0.5%) MD and 7 (0.1%) VMD. The overall CA for Gram-positive and Gram-negative organisms were 98.7% (2346 tests) and 96.2% (2942 tests), respectively. Seven VMD were observed, five for Gram-positive organisms (coagulase negative staphylococci (<n = 2) and Staphylococcus aureus (<n = 3)) and two for Gram-negative organisms (<Pseudomonas aeruginosa). Minor discrepancies were mainly observed in Gram-negatives and were related to different antimicrobial agents and species.     

Microbiological profile of canaliculitis and their antibiotic susceptibility patterns: A 11-year review at a referral eye care centre

PurposeTo analyze the microbiological profile and in vitro antibiotic susceptibility patterns of bacterial isolates in canaliculitis, an infection of the lacrimal drainage system of the eye.MethodsThe laboratory records of patients presenting with canaliculitis from whom specimens were obtained for microbiological investigations at our tertiary eye care centre in South India from January 2010 to December 2020, were reviewed.ResultsA total of 130 canalicular pus samples were collected from 112 patients and submitted for microbiological studies during the study period. A total of 183 micro-organisms were isolated from 115 culture-positive specimens. The micro-organisms isolated were predominantly aerobic Gram-positive bacteria (83.44%), with Coagulase-negative Staphylococci (CoNS/Other Staphylococcus spp) (31.69%), Corynebacterium spp (15.3%), Staphylococcus aureus (9.84%) and Viridans Streptococci (9.84%) accounting for a majority of the isolates. Actinomyces spp (6.56%) was the most common anaerobic bacterium isolated. Our study revealed several bacteria not previously associated with canaliculitis namely Ottowia spp, Elizabethkingia meningoseptica, Aeromonas salmonicida, Capnocytophaga ochracea and Campylobacter gracilis. Polymicrobial aetiology was observed in 39.13% of culture-positive samples. Analysis of antibiotic susceptibility patterns of the isolates revealed a high proportion of Gram-positive bacteria susceptible to chloramphenicol (90.16%) compared to fluoroquinolones including ciprofloxacin (74.42%), norfloxacin (64.15%) and gatifloxacin (60.49%).ConclusionThis study represents the largest series of canaliculitis reporting the microbiological profile and antibiotic susceptibilities of the isolated micro-organisms, till date. Gram-positive bacteria accounted for a majority of isolates, predominated by Staphylococcus spp. The increasing resistance of Gram-positive bacteria to fluoroquinolones warrants antibiotic treatment in canaliculitis is based on in vitro antimicrobial susceptibility patterns.     

Maternal colonization and early-onset neonatal bacterial sepsis in the Gambia,West Africa: a genomic analysis of vertical transmission

ObjectivesTo define bacterial aetiology of neonatal sepsis and estimate the prevalence of neonatal infection from maternal genital tract bacterial carriage among mother-newborn pairs.MethodsWe carried out a cross-sectional study of newborns with clinical sepsis admitted to three hospitals in the Gambia neonatal wards. Neonatal blood cultures and maternal genital swabs were obtained at recruitment. We used whole-genome sequencing to explore vertical transmission for neonates with microbiologically confirmed bloodstream infection by comparing phenotypically-matched paired neonatal blood cultures and maternal genital tract bacterial isolates.ResultsWe enrolled 203 maternal-newborn pairs. Two-thirds (67%; 137/203) of neonates presented with early-onset sepsis (days 0–6 after birth) of which 26% (36/137) were because of a clinically-significant bacterial pathogen. Blood culture isolates from newborns with early-onset sepsis because of Staphylococcus aureus (n = 5), Klebsiella pneumonia (n = 2), and Enterococcus faecalis (n = 1), phenotypically matched their maternal genital tract isolates. Pairwise single-nucleotide variants comparisons showed differences of 12 to 52 single-nucleotide variants only between maternal and newborn S. aureus isolates, presumably representing vertical transmission with a transmission rate of 14% (5/36).ConclusionsWe found a low prevalence of vertical transmission of maternal genital tract colonization in maternal-newborn pairs for early-onset neonatal sepsis in the West African context. Identifying infection acquisition pathways among newborns is essential to prioritize preventive interventions, which could be targeted at the mother or infection control in the hospital environment, depending on the major pathways of transmission.     

Identification of a methicillin-resistant Staphylococcus aureus inhibitory compound isolated from Serratia marcescens

In this study, we identified an antimicrobial compound produced by the Gram-negative bacterium Serratia marcescens. Colonies of S. marcescens inhibited the growth of nine different methicillin-resistant Staphylococcus aureus (MRSA) isolates and several other tested Gram-positive bacterial species, but not Gram-negative bacteria. Genetic analysis revealed the requirement for the swrW gene which codes for a non-ribosomal peptide synthetase that generates the cyclodepsipeptide antibiotic serratamolide, also known as serrawettin W1. This is the first report describing the anti-MRSA properties of serratamolide.     

Molecular Characterisation of Staphylococcus aureus Using spa Typing as a Diagnostic Tool in Haryana,India

Background: Staphylococcus aureus is one of the top six most common etiologic agents of nosocomial, community and livestock acquired bacterial infections. These infections although initially were described as a major problem in hospitals have now also become a serious threat in community not only in India but also worldwide. Its prevalence varies depending on the health-care setting, country or a particular region. Thus to better understand the epidemiology of methicillin-resistant S. aureus (MRSA) in a particular geographical location, it is important to study the variations in the population using molecular tools. Methods: This prospective study was carried out in the Department of Microbiology of Shree Guru Gobind Singh Tricentenary (SGT) Medical College. Staphylococcal protein A (spa) typing was done on 250 S. aureus isolates obtained from various clinical specimens including pus, wound swabs, urine, catheters, blood and cerebrosspinal fluid from both indoor and outdoor patients of SGT Hospital, Budhera, Gurgaon. Results: The selected region of the spa gene of all 250 isolates which includes 87 MRSA and 163 methicillin-susceptible S. aureus were amplified. The spa gene was detected in 248 out of 250 isolates (99.2%), whereas in 2 isolates (0.8%), it remained undetected and referred as non-typable isolates. The 248 S. aureus isolates were typed into 39 spa types, which clustered into six different spa clonal clusters and eight singletons. Conclusion: High diversity observed within S. aureus isolates indicated that many different strains circulate in the study region or in the hospital. The results would contribute in the understanding of epidemiology related to S. aureus spread and prevention.     

Predictors of the extended-spectrum-beta lactamases producing Enterobacteriaceae neonatal sepsis at a tertiary hospital,Tanzania

The study was conducted to establish predictors of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) neonatal sepsis and mortality in a tertiary hospital, Tanzania. Between July and December 2016, blood culture was performed in neonates with clinical features of sepsis and neonates/mothers/guardians were screened for ESBL colonization. Selected isolates underwent whole genome sequencing to investigate relatedness. Logistic regression analysis was performed to determine predictors for ESBL-PE associated neonatal sepsis and mortality. Neonatal ESBL-PE sepsis was detected in 32(10.5%) of the 304 neonates investigated. Neonatal ESBL-PE sepsis was independently predicted by admission at the Intensive care Unit and positive mother and neonate ESBL-PE colonization. Deaths occurred in 55(18.1%) of neonates. Neonates infected with ESBL-PE, admitted at ICU, increased age and those transferred from other centres had significantly high mortality rates. Gram-negative bacteria formed the majority (76%) of the isolates, of which 77% were ESBL-PE. Virulent Klebsiella pneumoniae ST45 carrying bla_CTX-M-15 were commonly isolated from neonates. Klebsiella pneumoniae (ST45) were the predominant cause of ESBL-PE neonatal sepsis and mortality. Improved infection control and antibiotic stewardship are crucial in controlling the spread of resistant strains. Rapid diagnostic tests to detect ESBL-PE in low-income countries are needed to guide treatment and reduce ESBL-PE-associated mortality.     

Clonal Clusters and Virulence Factors of Methicillin-Resistant Staphylococcus Aureus: Evidence for Community-Acquired Methicillin-Resistant Staphylococcus Aureus Infiltration into Hospital Settings in Chennai,South India

Background and Objective: Staphylococcus aureus is one of the major pathogens of nosocomial infections as wells as community-acquired (CA) infections worldwide. So far, large-scale comprehensive molecular and epidemiological characterisation of S. aureus from very diverse settings has not been carried out in India. The objective of this study is to evaluate the molecular, epidemiological and virulence characteristics of S. aureus in both community and hospital settings in Chennai, southern India. Methods: S. aureus isolates were obtained from four different groups (a) healthy individuals from closed community settings, (b) inpatients from hospitals, (c) outpatients from hospitals, representing isolates of hospital–community interface and (d) HIV-infected patients to define isolates associated with the immunocompromised. Antibiotic susceptibility testing, multiplex polymerase chain reactions for detection of virulence and resistance determinants, molecular typing including Staphylococcal cassette chromosome mec (SCCmec) and agr typing, were carried out. Sequencing-based typing was done using spa and multilocus sequence typing (MLST) methods. Clonal complexes (CC) of hospital and CA methicillin-resistant S. aureus (MRSA) were identified and compared for virulence and resistance. Results and Conclusion: A total of 769 isolates of S. aureus isolates were studied. The prevalence of MRSA was found to be 7.17%, 81.67%, 58.33% and 22.85% for groups a, b, c and d, respectively. Of the four SCCmec types (I, III, IV and V) detected, SCCmec V was found to be predominant. Panton-Valentine leucocidin toxin genes were detected among MRSA isolates harbouring SCCmec IV and V. A total of 78 spa types were detected, t657 being the most prevalent. 13 MLST types belonging to 9 CC were detected. CC1 (ST-772, ST-1) and CC8 (ST238, ST368 and ST1208) were found to be predominant among MRSA. CA-MRSA isolates with SCCmec IV and V were isolated from all study groups including hospitalised patients and were found to be similar by molecular tools. This shows that CA MRSA has probably infiltrated into the hospital settings.     

Review of a 7-Year Record of the Bacteriological Profile of Airway Secretions of Children with Cystic Fibrosis in North India

Background: Cystic fibrosis (CF) is now a recognised entity in India, with prevalence rates between 1/10,000 and 1/50,000. However, no data were available with regard to the profile of respiratory pathogens in the Indian setting. Materials and Methods: The records of respiratory secretion bacterial cultures of children with CF in a tertiary care hospital in North India from January 2010 to December 2016 were reviewed. Culture data were evaluated; the organisms were noted and their antimicrobial susceptibilities were analysed. The microbiological profile and antimicrobial susceptibility pattern of CF patients were evaluated. Results: A total of 445 samples from 146 children were processed, of which 246 (55%) samples showed bacterial growth. Mixed infections 48 (19.5%) were common in older children. Children aged 3–6 months (62.5%) showed the highest culture positivity. The most commonly isolated organisms were Pseudomonas aeruginosa (52.6%) and Staphylococcus aureus. Children with initial cultures positive for P. aeruginosa had 55% of their subsequent cultures showing polymicrobial infections. P. aeruginosa was most susceptible to ciprofloxacin (89%) and piperacillin-tazobactum (88%). Among the staphylococcal isolates, 38% were methicillin-resistant S. aureus (MRSA). The percentage of MRSA increased from 66% in 2010 to 75% in 2012, followed by a decline to 24% in 2016. Conclusions: The pattern of airway colonisation in the Indian setting is different from the Caucasian population, and P. aeruginosa and Burkholderia cepacia complex appear early. Colonisation with P. aeruginosa benefits from therapy. In case of infection, care must be taken while initiating empiric therapy. It should be based on local antibiograms to prevent the emergence of resistant microbes.     

Antibiotic sensitivity pattern of causative organisms of neonatal septicemia in an urban hospital of Bangladesh

Background: The information of the sensitivity pattern of the causative organisms is very important for effective control of septicemia in neonates. OBJECTIVE: To determine the proportion and profile of pathogenic bacteria in the blood cultures of the neonates with clinically suspected septicemia and their susceptibility pattern to antimicrobial agents for developing a unified antibiotic treatment protocol. Materials and Methods: A cross-sectional retrospective study was conducted over a period of 3 year and 4 months (39 months). The study included 1000 patients admitted in the selected hospital in Bangladesh. Blood samples for culture were taken aseptically before starting antibiotic therapy. Microorganisms were isolated and identified by standard microbiological processes which include colony morphology, Gram stain, and biochemical profiles. Antimicrobial sensitivity patterns were performed by Kirby-Bauer's disc diffusion method against imipenem, ciprofloxacin, ceftazidime, chloramphenicol, netilmicin, gentamicin, ceftriaxone, aztreonam, cefotaxime, cephalexin, and ampicillin. Results: Among the patients, 633 (63.3%) were males and 367 (36.7%) were females. Blood cultures were found positive in 194 (19.4%) neonates. The organisms isolated were Pseudomonas spp. (31.4%), Klebsiella pneumoniae (23.2%), Staphylococcus aureus (12.4%), Escherichia coli (7.2%), Acinatobactor (5.7%), Gram-negative Bacilli (4.1%), Flavobacterium spp. (3.6%), Serratia spp. (5.7%), Citrobacter fruendi (3.1%), Streptococcus species (2.6%), and Enterobacter spp. (1.0%). A majority of the bacterial isolates in neonatal sepsis were found sensitive to imipenem (91.8%) and ciprofloxacin (57.2%) and resistant to commonly used antibiotics, eg. ampicillin (96.4%) and cephalexin (89.2%). Conclusion : The problem can be mitigated by careful selection and prudent use of available antibiotics.     

Susceptibility of common aerobic pathogens to tigecycline: results of a surveillance study in Germany

Tigecycline is a novel antimicrobial agent for parenteral use encompassing a broad spectrum of bacterial pathogens, including multi-resistant organisms. Here, we report the results of the first nationwide surveillance trial that was conducted in order to evaluate the susceptibility of bacterial isolates to tigecycline in a European country prior to its clinical use. A total of 2,610 Gram-positive and Gram-negative organisms recovered from hospitalized patients were tested. Minimum inhibitory concentrations (MICs) were determined using the microdilution method. All enterococci, staphylococci (including methicillin-resistant Staphylococcus aureus; MRSA), and streptococci tested were tigecycline-susceptible, except one isolate of Staphylococcus haemolyticus. Among the Gram-negative bacteria, 100% of the Escherichia coli isolates (including extended spectrum β-lactamase [ESBL]-producers) were tigecycline-susceptible, while about 10% of the Enterobacter cloacae and Klebsiella pneumoniae isolates were resistant. Based on the results of this surveillance study, tigecycline may represent a suitable option most notably for the empiric treatment of bacterial mixed infections, including in clinical situations in which multi-resistant organisms are suspected. Members of the G-TEST Study Group are listed in the Acknowledgments section.     

Epidemiological characterisation of Streptococcus pneumoniae from India using multilocus sequence typing

Objective: The aim of this study was to utilize the multilocus sequence typing (MLST) technique to characterise Streptococcus pneumoniae among clinical isolates in India. MLST was used to determine clonality, to establish genetic relatedness, to check for correlation between serotypes and sequence types (STs) and its relevance associated with antibiotic resistance. Methods: Forty consecutive invasive S. pneumoniae isolates in children <5 years were characterised. Preliminary identification of serotype and antibiotic susceptible profile was followed with MLST technique to identify the STs of the isolates. STs were then analysed for clonality using an eBURST algorithm and genetic relatedness using Sequence Type Analysis and Recombinational Tests version 2 software. Results: The most common ST was ST63. Among the forty isolates, we identified nine novel STs, six of which had known alleles but in new combinations, three of which had new alleles in their sequence profile. The new STs assigned were 8501–8509. One clonal complex was found among the 40 strains characterised. The most common serotypes in this study were serotype 19F, 14 and 5. Non-susceptibility to penicillin and erythromycin was observed in 2.5% and 30% of the isolates, respectively. Conclusion: This study shows a significant number of novel STs among the 40 isolates characterised (9/40, 22.5%), however, internationally recognised strains were also circulating in India, indicating, there could be greater geographical variation in pneumococcal STs in India. Molecular epidemiology data is essential to understand the population dynamics of S. pneumoniae in India before the introduction of pneumococcal vaccines in NIP in India.     

First case series of emerging Rickettsial neonatal sepsis identified by polymerase chain reaction-based deoxyribonucleic acid sequencing

Purpose: To detect and identify the aetiological agent in the peripheral blood from the cases of neonatal sepsis. Materials and Methods: Four neonates from geographically different regions of South India presented with signs of neonatal sepsis and all the routine clinical and laboratory investigations were performed. Blood culture by Bac T Alert 3D was negative. To establish the aetiology, polymerase chain reaction (PCR) for eubacterial genome and subsequent amplification with Gram positive and Gram negative primers were performed followed by deoxyribonucleic acid (DNA) sequencing. Results: PCR for the detection of eubacterial genome was positive in all the four neonates and further amplification with designed Gram positive and Gram negative primers revealed the presence of Gram negative bacteria. The amplicons were identified as Orientia tsutsugamushi in three neonates and Coxiella burnetti in the other neonate. Multalin analysis was done to further characterise the strain variation among the three strains. Conclusion: PCR-based DNA sequencing is a rapid and reliable diagnostic tool to identify the aetiological agents of neonatal sepsis. This is the first case series of emerging Rickettsial neonatal sepsis in India.     

Inducible clindamycin resistance in Staphylococcus aureus isolated from clinical samples

Purpose: Clindamycin is commonly used in the treatment of erythromycin resistant Staphylococcus aureus causing skin and soft tissue infections. In vitro routine tests for clindamycin susceptibility may fail to detect inducible clindamycin resistance due to erm genes resulting in treatment failure, thus necessitating the need to detect such resistance by a simple D test on routine basis. Materials and Method: 247 Staphylococcus aureus isolates were subjected to routine antibiotic susceptibility testing including oxacillin (1μg) by Kirby Bauer disc diffusion method. Inducible clindamycin resistance was detected by D test, as per CLSI guidelines on erythromycin resistant isolates. Results: 36 (14.5%) isolates showed inducible clindamycin resistance, nine (3.6%) showed constitutive resistance while remaining 35 (14.1%) showed MS phenotype. Inducible resistance and MS phenotype were found to be higher in MRSA as compared to MSSA (27.6%, 24.3% and 1.6%, 4% respectively). Conclusion: Study showed that D test should be used as a mandatory method in routine disc diffusion testing to detect inducible clindamycin resistance.     

Prevalence and Genetic Mechanisms of Antimicrobial Resistance in Staphylococcus Species: A Multicentre Report of the Indian Council of Medical Research Antimicrobial Resistance Surveillance Network

Purpose: Routine surveillance of antimicrobial resistance (AMR) is an essential component of measures aimed to tackle the growing threat of resistant microbes in public health. This study presents a 1-year multicentre report on AMR in Staphylococcus species as part of Indian Council of Medical Research-AMR surveillance network. Materials and Methods: Staphylococcus species was routinely collected in the nodal and regional centres of the network and antimicrobial susceptibility testing was performed against a panel of antimicrobials. Minimum inhibitory concentration (MIC) values of vancomycin (VAN), daptomycin, tigecycline and linezolid (LNZ) against selected methicillin-resistant Staphylococcus aureus (MRSA) isolates were determined by E-test and MIC creep, if any, was determined. Resistant genotypes were determined by polymerase chain reaction for those isolates showing phenotypic resistance. Results: The prevalence of MRSA was found to be range from moderate (21%) to high (45%) among the centres with an overall prevalence of 37.3%. High prevalence of resistance was observed with commonly used antimicrobials such as ciprofloxacin and erythromycin in all the centres. Resistance to LNZ was not encountered except for a single case. Full-blown resistance to VAN in S. aureus was not observed; however, a few VAN-intermediate S. aureus isolates were documented. The most common species of coagulase negative staphylococci (CoNS) identified was Staphylococcus haemolyticus and Staphylococcus epidermidis. Resistance among CoNS was relatively higher than S. aureus. Most phenotypically resistant organisms possessed the corresponding resistance genes. Conclusion: There were localised differences in the prevalence of resistance between the centres. The efficacy of the anti-MRSA antimicrobials was very high; however, almost all these antimicrobials showed evidence of creeping MIC.     

Continuous Ambulatory Peritoneal Dialysis Peritonitis: Microbiology and Outcomes

Context: Continuous ambulatory peritoneal dialysis (CAPD) is now a preferred mode of the treatment in patients with end-stage renal disease, but peritonitis remains to be a shortcoming of CAPD. High-culture negativity, emerging drug resistance and peritoneal dialysis (PD)-related morbidity and mortality have been a challenge to tackle. Aims: The present study was taken up to compare the the various culture methods and to identify the spectrum of organisms causing CAPD peritonitis and their outcome. Settings and Design: A prospective, observational, cross-sectional study was conducted at a tertiary care teaching hospital in Hyderabad over a period of 1 year. Subjects and Methods: Dialysate fluid from 100 episodes of clinically suspected peritonitis in 75 patients was processed by conventional centrifuging, water lysis, direct inoculation and addition of centrifuged pellet into brain–heart infusion broth and by automated blood culture system. Identification and antibiotic susceptibility of organisms was done, and the outcome of PD-related peritonitis was analysed. Statistical Analysis Used: The categorical data and continuous data were analysed using the Chi-square test and Student’s t-test, respectively. P < 0.05 was considered statistically significant. Results: Of the 100 PD fluids, 87 were culture positive. Automated blood culture systems detected 87 episodes, whereas conventional centrifuge method detected only 53 episodes (P = 0.00001). Peritonitis due to Gram-negative organisms (62.3%) was higher than that of Gram-positive peritonitis (31.1%) and fungi (6.4%). Nineteen per cent episodes were constituted by relapse (9), refractory (4), recurrent (4) and repeat (2) peritonitis. Outcomes were analysed as recovery (77%), catheter removal (15%) and death (2.6%). Conclusions: Direct inoculation of peritoneal fluid into automated blood culture bottles increases the positivity rate and also aids in the early detection of CAPD peritonitis, helping reduce morbidity and mortality of PD patients.     

Carriage of encapsulated bacteria in Gabonese children with sickle cell anaemia

Sickle cell anaemia (SCA) is a haemoglobin disorder that alters the deformability of erythrocytes through abnormal polymerization of haemoglobin. Children with SCA have an increased risk of infections with encapsulated bacteria. To guide the antibiotic prophylaxis and vaccinations in children with SCA in Gabon, we characterized Streptococcus pneumoniae, Staphylococcus aureus and Haemophilus influenzae from children with and without SCA. We performed a cross-sectional study and compared nasal and pharyngeal S. pneumoniae, Staph. aureus and H. influenzae isolates from SCA children (n = 73) with comparators matched for age, residence and sex (n = 143) in a matched-comparison analysis. The resistance pattern and capsular type were identified for each isolate. The total carriage rate for S. pneumoniae, Staph. aureus and H. influenzae was 13.8%, 46.7% and 12.5%, respectively, and did not differ between groups (p >0.05). The mean number of days under antibiotic treatment in the past year was higher in children with SCA than in controls (penicillin: 70.1 vs 0.1 days, p 0.00002). The total non-susceptibility rate was 30% for oral and parenteral (meningitis) penicillin in S. pneumoniae, resistance rates were 1.6% for oxacillin in Staph. aureus and 14.8% for ampicillin in H. influenzae. Susceptibility to antibiotic agents and distribution of capsular types did not differ significantly between both groups. In conclusion, carriage and resistance rates are similar in children with and without SCA. Our data provide the basis to guide empiric therapy of invasive diseases caused by S. pneumoniae, Staph. aureus and H. influenza in children in Gabon.     

Molecular epidemiology of Staphylococcus aureus strains isolated from inpatients with infected diabetic foot ulcers in an Algerian University Hospital

Staphylococcus aureus is the most common pathogen cultured from diabetic foot infection (DFI). The consequence of its spread to soft tissue and bony structures is a major causal factor for lower-limb amputation. The objective of the study was to explore ecological data and epidemiological characteristics of S. aureus strains isolated from DFI in an Algerian hospital setting. Patients were included if they were admitted for DFI in the Department of Diabetology at the Annaba University Hospital from April 2011 to March 2012. Ulcers were classified according to the Infectious Diseases Society of America/International Working Group on the Diabetic Foot classification system. All S. aureus isolates were analysed. Using oligonucleotide arrays, S. aureus resistance and virulence genes were determined and each isolate was affiliated to a clonal complex. Among the 128 patients, 277 strains were isolated from 183 samples (1.51 isolate per sample). Aerobic Gram-negative bacilli were the most common isolated organisms (54.9% of all isolates). The study of ecological data highlighted the extremely high rate of multidrug-resistant organisms (MDROs) (58.5% of all isolates). The situation was especially striking for S. aureus [(85.9% were methicillin-resistant S. aureus (MRSA)], Klebsiella pneumonia (83.8%) and Escherichia coli (60%). Among the S. aureus isolates, 82.2% of MRSA belonged to ST239, one of the most worldwide disseminated clones. Ten strains (13.7%) belonged to the European clone PVL+ ST80. ermA, aacA-aphD, aphA, tetM, fosB, sek, seq, lukDE, fnbB, cap8 and agr group 1 genes were significantly associated with MRSA strains (p <0.01). The study shows for the first time the alarming prevalence of MDROs in DFI in Algeria.     

Rapid Detection of Gram-Positive Organisms by Use of the Verigene Gram-Positive Blood Culture Nucleic Acid Test and the BacT/Alert Pediatric FAN System in a Multicenter Pediatric Evaluation

Assays that expedite the reporting of organism identification and antibiotic susceptibility status in positive blood cultures can fast track interventions that improve clinical outcomes. We evaluated the Verigene Gram-positive blood culture nucleic acid test (BC-GP) in two pediatric hospitals. Positive BacT/Alert Pediatric FAN blood cultures with Gram-positive organisms were tested using the BC-GP in tandem with routine laboratory procedures. To test organisms underrepresented in the clinical blood culture evaluation, blood culture bottles were spiked with diluted organism suspensions at concentrations of 10 to 100 CFU per milliliter. A total of 249 Gram-positive bacterial isolates were recovered from 242 blood cultures. The BC-GP detected Staphylococcus aureus, methicillin-susceptible S. aureus, and methicillin-resistant S. aureus with sensitivities of 100%, 99%, and 100% and specificities of 100%, 100%, and 99.5%, respectively. The BC-GP detected Staphylococcus epidermidis, methicillin-susceptible S. epidermidis, and methicillin-resistant S. epidermidis with sensitivities of 95%, 80%, and 96%, respectively, and 100% specificity. The BC-GP correctly identified 14/15 cases of Enterococcus faecalis and Enterococcus faecium bacteremia and 9 cases of Streptococcus pneumoniae. It misidentified 5/15 clinical blood cultures with Streptococcus mitis/Streptococcus oralis and 1/3 blood cultures spiked with Streptococcus anginosus group as S. pneumoniae. The BC-GP detected a case of Streptococcus pyogenes bacteremia but failed to detect 2/3 clinical blood cultures with Streptococcus agalactiae. BC-GP''s rapid accurate detection of Staphylococcus spp., E. faecium, and E. faecalis and its ability to ascertain mecA, vanA, and vanB status may expedite clinical decisions pertaining to optimal antibiotic use. False-positive S. pneumoniae results may warrant reporting of only “Streptococcus spp.” when this organism is reported by the BC-GP.