Identification Of Causative Bacteria Research Articles

Antimicrobial therapy and assessing therapeutic response in culture-negative pyogenic vertebral osteomyelitis: a retrospective comparative study with culture-positive pyogenic vertebral osteomyelitis

BackgroundThere are still controversies regarding the treatment and outcomes in culture-negative pyogenic vertebral osteomyelitis (PVO). The purpose of this study is to investigate the antimicrobial therapy, assessment of therapeutic response, and outcome of culture-negative PVO compared to culture-positive PVO.MethodsA retrospective study was performed with non-surgical lumbar PVO patients. The patients were divided into two groups based on the causative bacterial identification (CN group with culture-negative PVO and CP group with culture-positive PVO). The clinical features, use of antibiotics, laboratory data, and outcomes were compared between the two groups.ResultsSeventy-three patients with 41 (56.2%) of the CN group and 32 (43.8%) of the CP group were enrolled. The CN group showed a shorter duration of parenteral antibiotics (45.88 ± 16.14 vs. 57.31 ± 24.39, p = 0.019) but a tendency of prolonged duration of total (parenteral + oral) antibiotics (101.17 ± 52.84 vs. 84.19 ± 50.29 days, p = 0.168). When parenteral antibiotics were discontinued or switched to oral antibiotics, the mean erythrocyte segmentation rate (ESR, normal range: < 25 mm/h), C-reactive protein (CRP, normal range: < 0.5 mg/dL) level, and visual analog scale (VAS) score of back pain were 42.86 ± 24.05 mm/h, 0.91 ± 1.18 mg/dL, and 4.05 ± 1.07, respectively, with no significant differences between the two groups. The recurrence rates of CN and CP groups were 7.3% (3/41) and 6.3% (2/32), respectively (p = 1.000). The presence of epidural abscess was the most significant factor for the identification of causative bacteria (p = 0.002), and there was no significant relationship between the use of empirical antibiotics before tissue culture and the causative bacterial identification (p = 0.194).ConclusionsThe CN group required a shorter duration of parenteral antibiotics than the CP group. Discontinuation of parenteral antibiotics or changing the administration route can be considered based on the values of ESR, CRP, and VAS score of back pain. The presence of epidural abscess was the most significant factor for the identification of causative bacteria.

Studies on Biocementation of Mortar and Identification of Causative Bacteria

A major challenge for construction industry is the durability of structures. A lot of work is being done to strengthen structures. Microbially induced calcium carbonate precipitation (MICCP) or biocementation is an innovative technology, which uses ureolytic bacteria to precipitate CaCO3 to strengthen cementitious materials. In this research, the effect of a bio-solution incorporated with soil as microbial source on the mechanical properties of mortar was studied. Cost reduction in the process was done by using natural ingredients. A considerable increment in compressive strength and a decrement in water absorption of the bio-mortar specimens were observed. Two ureolytic bacteria were identified, viz. Bacillus cereus and Enterobacter cloacae. The effect of these identified ureolytic pure cultures on mortar was also studied.

Neonatal sepsis: Bacteriological profile,molecular detection and antimicrobial susceptibility test among pre-term pediatrics in Erbil city, Iraq

Background and objective: Neonatal sepsis refers to infection occurring within the neonatal period, the first 28 days of life for a term baby, and up to 4 weeks beyond the expected date of delivery in a pre-term baby. This study was designed to determine the frequency of neonatal early onset sepsis and late onset sepsis in some hospitals in Erbil city. Methods: Out of 170 neonate samples from Neonatal Intensive Care Unit in Rapareen Pediatric Teaching Hospital and Maternity Obstetric Hospital randomly were studied through isolation and identification of causative bacteria using the traditional approach, VITEK 2 compact system, molecular detection using PCR technique, moreover, C-reactive protein and white blood cell count detected as biomarker assay. The isolated bacteria tested against some widely used antibiotics. Results: The sepsis was confirmed in 54 (31.76%) patients of total neonates with suspected cases of sepsis by clinical signs and symptoms. EOS was 42 (77.77%) were detected, and late onset sepsis was 12 (22.23%). Identification of the isolated bacteria by the traditional method, and VITEK 2 compact system were performed. In addition, molecular detection via the PCR system through the detection of the specific genes was performed. Antimicrobial Susceptibility test indicated that most of the isolated bacteria were developed resistant to the most widely used antimicrobials. Conclusion: Our study showed a high incidence of neonatal early onset sepsis more than late onset sepsis, mostly associated with Gram-negative bacteria than Gram-positive bacteria.

Molecular diagnosis of polymicrobial brain abscesses with 16S-rDNA-based next-generation sequencing

ObjectivesBrain abscesses lead to high mortality despite antibiotic and surgical treatment. Identification of causative bacteria is important to guide antibiotic therapy, but culture-based methods and molecular diagnostics by Sanger sequencing of 16S PCR products are hampered by antibiotic treatment and the often polymicrobial nature of brain abscesses. We have applied 16S-rRNA-based next-generation sequencing (NGS) for metagenomic analysis of intracranial abscess (brain and epidural) and meningitis samples. MethodsSeventy-nine samples from 54 patients with intracranial abscesses or meningitis were included. DNA was subjected to 16S PCR. Amplicons were analysed with the Illumina MiSeq system, sequence reads were blasted versus the NCBI 16S bacterial database and analysed using MEGAN software. Results were compared to those of gram-staining, culture and Sanger sequencing. ResultsThe NGS workflow was successful for 51 intracranial abscesses (46 brain and five epidural) and nine meningitis samples. Inclusion of (mono)bacterial meningitis samples allowed us to establish a cut-off criterion for the exclusion of contaminating sequences. In total 86 bacterial taxa were identified in brain abscesses by NGS, with Streptococcus intermedius and Fusobacterium nucleatum as most prevalent species; Propionibacterium and Staphylococcus spp. were associated with epidural abscesses. NGS identified two or more bacterial taxa in 31/51 intracranial abscesses, revealing the polymicrobial nature of these infections and allowing the discrimination of up to 16 bacterial taxa per sample. ConclusionThese results extend earlier studies showing that NGS methods expand the spectrum of bacteria detected in brain abscesses and demonstrate that the MiSeq platform is suitable for metagenomic diagnostics of this severe infection.

521: Intra-amniotic injection alters the intrauterine microbiome in a primate model of inflammatory preterm birth

Identification of causative bacteria in chorioamnionitis has been unyielding, and our prior work examining the intrauterine microbiome in association with histological chorioamnionitis demonstrates the presence of bacteria in the placental membranes that is normally found within oral and vaginal cavities. Here, we aimed to examine changes in the intrauterine microbiome that occur in a primate model of inflammatory preterm birth. Sterile intra-amniotic injections (IA) of saline, lipopolysaccharide (LPS), IL-1B, or Ureaplasma parvum were given to preterm (126-132 days) Rhesus macaques (n=23) with ultrasound guidance. Delivery of offspring occurred via cesarean within one week post-injection. Sterile techniques was utilized in the collection and DNA extraction of oral swabs, stool, placental tissue, vaginal swabs, and meconium. Next-generation sequencing (16S and whole genome shotgun (WGS)) of DNA was performed with negative controls, and resultant sequences were quality filtered prior to analysis. Analysis of 16S sequencing was performed with QIIME, LEfSe, GENE-E, and PICRUSt. Analysis of WGS sequencing was performed using HUMAnN and MG-RAST. Integrative analysis was used to determine the relationships of the microbiome alterations in each cohort with relation to bacterial metabolic pathways. As expected, microbiota of the maternal oral and vaginal cavities was not significantly altered by intra- amniotic injection of LPS, IL-1B, nor U. parvum when examining alpha (Fig. A) and beta diversity. However, intrauterine microbiota were significantly altered by both alpha (p<0.03, Fig. A) and beta (p=0.02, Fig. B) diversity with intra-amniotic injection of inflammatory mediators in comparison to control animals. Furthermore, we found clustering of samples by control or inflammatory injection when examining hierarchal clustering by Spearman’s correlation (Fig. C). This study demonstrates the presence of bacteria in the intrauterine environment due to alterations occurring in placenta microbiota with exposure to inflammatory mediators. Additionally, we find that inflammatory mediators significantly alter the intrauterine microbiome in a clinically relevant primate model.

Clinical manifestation of Campylobacter enteritis in children.

PurposeTimely antibiotic therapy in selected cases of diarrhea associated with bacterial infections can reduce the duration and severity of illness and prevent complications. The availability of a predictive index before identification of causative bacteria would aid in the choice of a therapeutic agent.MethodsThe study included patients admitted to the pediatrics unit at Konyang University Hospital for acute inflammatory diarrhea from August 1, 2015 to July 31, 2016 who underwent multiplex polymerase chain reaction testing. Of 248 patients, 83 had positive results. The clinical symptoms and blood test results were examined in 61 patients with Campylobacter spp. (25 patients), Salmonella spp. (18 patients), and Clostridium perfringens (18 patients) infections. The mean age of the 61 patients (male:femal=31:30) was 84.0±54.8 months, and the mean hospital stay was 4.6±1.7 days.ResultsThere were no statistical differences in sex, age, clinical symptoms, or signs. Patients with Campylobacter infection were significantly older (P=0.00). C-reactive protein (CRP) levels in patients with Campylobacter infection were higher than those in the other 2 groups, at 9.6±6.1 mg/dL. The results of receiver-operating characteristic curve analysis showed that the cutoff age was ≥103.5 months (sensitivity, 72%; specificity, 86%) and the CRP cutoff level was ≥4.55 mg/dL (sensitivity, 80%; specificity, 69%).ConclusionAge (≥103.5 months) and higher CRP level (≥4.55 mg/dL) were good predictors of Campylobacter enterocolitis. If neither criterion was met, Campylobacter enterocolitis was unlikely (negative predictive value 97.2%). When both criteria were met, Campylobacter enterocolitis was highly likely.

HIGH VAGINAL SWABS;

Normal vaginal flora contains a wide range of microorganisms. Hydrogen peroxideproduced by Lactobacillus strains plays a vital role in maintaining the microenvironment of thevagina and in the inhibition of overgrowth of potentially pathogenic bacteria. Bacterial vaginosisBV is the main reason of vaginal discharge. Many gram positive and gram negative rods i.e.E.coli, Klebsiella, Proteus, Acinetobacter and Pseudomonas spp. are major contributors inbacterial vaginosis. Aim: The present study was conducted to elucidate the frequency of variousgram-negative rods in high vaginal swabs and sensitivity pattern of bacteria to antibiotics thatare currently used. Study Design: Cross sectional study. Setting: Department of Obstetricsand Gynecology of Benazir Bhutto Hospital Rawalpindi, a tertiary health care center for thepeople of Rawalpindi. Period: January 2015 to May 2016. Material and Methods: A total of220 High vaginal swabs (HVS) were collected both from indoor and outdoor patients presentingwith symptoms of vaginal discharge aged between 20 to 65 years. Swabs were inoculated onblood, Chocolate and MacConkey’s agar. After overnight incubation plates were examined forgrowth, colonial morphology, final confirmation was done on the basis of biochemical testingand API 20-E system (BioMerieux, France) up to species level. Antibiotic sensitivity testing wasdone by (modified Kirby-Bauer’s) disc diffusion method using amikacin, ampicillin, amoxicillinclavulanic acid, imipenem, ceftazidime, tigecycline, ciprofloxacin, sulzone and cefixime. Afterovernight incubation plates were examined to read the susceptibility zone. Results: Out of 220HVS samples, 100 samples showed bacterial growth and confirmed as Gram negative bacilli.Age wise distribution of infection showed highest rates b/w age 20-30 was 36% followed by 31-40 (23%), 41-50 (25%) and 11% above 50 years of age. Bacteria isolated from HVS were E.coli(53%), Klebsiella (22%), Pseudomonas (12%), citrobacter (6%), Proteus (5%) and Acinetobacter(2%) respectively. Highly sensitive antibiotics against bacteria were imipenem (96%), sulzone(90%) and Ciprofloxacin (88%), whereas least affective antibiotics against gram negative rodswere penicillins (ampicillin, amoxicillin-clavulanic acid), amikacin due to indiscriminate use ofantibiotics. Conclusion: High prevalence of gynecological infections demands that the patientswho have vaginosis must be investigated regularly and carefully through culture and identificationof causative bacteria. Emergence of antibiotic resistance must be controlled in order to avoidimproper use, frequent abuse, insufficient dosages, trouble-free availability of antibiotics andtreatment schedule must be designed subsequent to proper laboratory investigations.

Management of empyema in children

The incidence of empyema complicating community-acquired pneumonia is increasing and causes significant childhood morbidity. Pneumococcal infection remains the most common isolated cause in developed countries, with Staphylococcus aureus the predominant pathogen in the developing world. Newer molecular techniques utilizing the polymerase chain reaction have led to an increase in identification of causative bacteria, previously not isolated by conventional culture techniques. This remains an important epidemiological tool, and may help in guiding correct antibiotic use in the future. There are many treatment options, however, and the care a child currently receives is dependent on local practice, which is largely determined by availability of medical personnel and their preferences. Although there are many reported case series comparing treatment options, only two randomized controlled studies exist to guide treatment in children. There is an urgent need for this to be addressed, particularly with the introduction of relatively new surgical techniques such as video-assisted thorascopic surgery.

Pattern of Occurrence of Single and Concurrent Diseases Associated with Mortality in Commercial Chickens in Bangladesh

The high mortality rate of commercial poultry has been encountered as a major problem which discourage farmers and entrepreneurs in this industry in Bangladesh. This study was carried out to determine the role of single and concurrent infections associated with mortality in 1751 commercial chickens during one year period from January to December 2002. Diagnosis of diseases was made on the basis of history, necropsy findings, isolation and identification of causative bacteria and other laboratory tests. The etiological investigations of 1751 dead chickens showed that about 39.81% bacterial, 22.73% viral, 13.65% mycoplasmal, 1.54% fungal, 10.11% parasitic, 31.64% systemic, 3.43% nutritional deficiency and 1.77% other diseases were associated with these mortality. Salmonellosis (21.99%), Colibacillosis (8.40%), Fowl cholera (6.52%), Avian mycoplasmosis (13.65%), Infectious bursal disease (11.20%), Newcastle disease (10.34%) and coccidiosis (6.23%) were recognized as major diseases associated with mortality in commercial chickens in Bangladesh. About 32 diseases were recorded, of which both single (76.30%) and mixed infections as two (21.53%), three (1.83%) and four (0.34%) types were associated with mortality of chickens. Significantly (p &lt; 0.01) highest proportionate mortality rate was recorded in &gt; 20 weeks old adult layer (45.52%) in comparison to &gt; 2 to 8 weeks old grower (24.04%), &gt; 8 to 20 weeks old pullet (18.16%) and up to 2 weeks old brooding (12.28%) chickens. Seasonal influence showed highest mortality rate during Summer (43.06%) in comparison to Rainy (27.81%) and Winter (29.13%) seasons. It may be concluded from this study that both the single and concurrent infections are associated with high mortality rate in commercial chickens in Bangladesh. Therefore, the interactions of different pathogens in naturally occurring diseases should be considered during diagnosis and evaluation of vaccination.  Key words: Occurrence; concurrent; mortality; diseases; chickens DOI = 10.3329/bjvm.v1i1.1911 Bangl. J. Vet. Med. (2003). 1 (1) :  15 - 20