Saba Riaz

Bacteriocins produced by L fermentum and L acidophilus can inhibit cephalosporin resistant E coli

Reemerging infections occur due to resistant bacteria. Such infections create restrictions for clinicians and microbiologists in drug selection. Such problems demand new strategies for solution. Use of bacteriocins for this purpose may be fruitful. In the present research work, the inhibitory effects of bactericins on cephalosporin resistant Escherichia coli are used as model system for the control of antibiotic resistant pathogenic bacteria. Cephalosporin resistant Escherichia coli strain was isolated from pus by using conventional methodology. For bacteriocin production, Lactobacilli strains were selected by using selective media. Out of seventy two strains isolated from yogurt, fecal materials of human, chick, parrot and cat, only two strains (strain 45 and strain 52) were found to produce bacteriocins having antimicrobial potential against cephalosporin resistant Escherichia coli. Biochemical characterization showed that strain 45 belonged to group of Lactobacillus fermentum and strain 52 to Lactobacillus acidophilus. Both strains showed maximum growth at 25°C and 35°C respectively. Suitable pH was 5.5 and 6.0 for Lactobacillus fermentum and Lactobacillus acidophilus respectively. Bacteriocins produced by both strains were found stable at 50, 75 and 100°C for 60min. Function of bacteriocin was also not disturbed due to change in pH. These findings suggest that bacteriocin produced by Lactobacillus fermentum and Lactobacillus acidophilus can be used for the infection control of cephalosporin resistant Escherichia coli.

Association of genotypes with viral load and biochemical markers in HCV-infected Sindhi patients

The presented study had two objectives. The first was to examine distributions of Hepatitis C Virus (HCV) genotypes in Sindh, Pakistan, where HCV is prevalent. The other was to explore clinically relevant relationships between the genotypes, viral load (measured by real-time polymerase chain reaction assays) and biochemical markers. For this, 1471 HCV-infected patients in six cities in Sindh were recruited and sampled. HCV genotype distributions varied among the cities, but genotype 3a was most prevalent, followed by 3b, 1a and 1b (detected in 51.5, 22.7. 9.25 and 3.2% of the cases, respectively). No type-specific sequences were detected in serum samples from 189 (12.8%) of the 1471 patients. Frequencies of low (<200,000 IU/mL serum), intermediate (200,000–600,000 IU/mL serum) and high (>600,000 IU/mL serum) viral loads were respectively 45.4, 16.5 and 38.1% for patients infected with genotype 3, and 16.9, 36.9 and 46.2%, respectively, for patients with other genotypes. Infection with genotype 1a was associated with significantly higher (p < 0.005) alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase titers than infection with genotype 3a. The results will help in the formulation of treatment strategies.

GeneXpert technology. A breakthrough for the diagnosis of tuberculous pericarditis and pleuritis in less than 2 hours

Objectives: To evaluate the diagnostic validity of GeneXpert for the detection of Mycobacterium tuberculosis (MTB) in pericardial and pleural effusions samples. Methods: A cross sectional study was conducted at the Mycobacteriology Laboratory, Allama Iqbal Medical College, Lahore, Pakistan. A total of 286 (158 pleural and 128 pericardial fluids) samples were received from tuberculosis (TB) suspects between January 2014 and August 2016. Every sample was processed for Ziehl-Neelsen (Zn) smear, Lowenstein Jensen (LJ) culture, GeneXpert MTB/RIF assay according to standard protocols. Validity of GeneXpert assay for the detection of MTB was evaluated using LJ culture as gold standard. Results: Out of 286 effusions samples, MTB was isolated by LJ culture in 51 (17.8%) samples followed by GeneXpert in 43 (15%), and acid- fast bacilli (AFB) was detected by Zn smear microscopy in 11 (3.8%) samples. GeneXpert showed high sensitivity (84.3%), specificity (100%), with positive predictive value (100%), and negative predictive value (96.7%), while Zn smear showed sensitivity 18.3%, specificity 99.1%, positive predictive value 81.8%, and negative predictive value 85.4%. A strikingly high sensitivity of 72.2% was observed for pericardial fluid by GeneXpert. Conclusion: GeneXpert assay is an innovative tool, for prompt detection of MTB and drug resistance. It is definitely an attractive point of care test, with high sensitivity and specificity along with turn around time of 2 hours, which facilitates timely diagnosis and appropriate management of TB pleuritis and pericarditis.

Pseudomonas Aeruginosa: Evaluation Of Pathogen Burden And Drug-resistance Trends In A Tertiary Care Hospital

OBJECTIVE To evaluate the pathogen burden and antibiotic-resistance trends of Pseudomonas aeruginosa among hospitalised patients at a tertiary care hospital. STUDY DESIGN Retrospective, hospital record-based, cross-sectional study. PLACE AND DURATION OF STUDY Microbiology Laboratory, Allama Iqbal Medical College/Jinnah Hospital, Lahore, from January 2014 to December 2016. METHODOLOGY A total of 5,960 samples were collected from clinically suspected cases of bacterial infections, admitted to the hospital. Microbial identification and antibiotic susceptibility pattern were carried out and analysed. RESULTS Out of a total of 5,960 samples, Pseudomonas aeruginosa was isolated from 1,268 (21.2%) specimens. Department-wise isolation rate was n=600 (42.9%), n=268 (15.4%), n=201 (12.6%), and n=199 (16.0%) from intensive care unit (ICU), surgical units, medical units, and Gynae wards, respectively (p<0.0001). Sample-wise isolation rate was, wound swabs n=448 (35%), urine n=356 (28%), sputum n=187 (14 %), tracheal aspirate n=127 (10%), blood n=99 (7%), and broncho-alveolar lavage n=51 (4%) (p<0.0001). Drug-resistance pattern showed low rates for carbapenems(meropenem n=440 (35%), Imipenem n=436 (34%) and beta-lactam + beta-lactamase inhibitor combination (piperacillin+tazobactam n=437 (34%) while alarming rates were observed for cephalosporins (ceftazidime n=716 (56%), fluoroquinolones (ciprofloxacin n=690 (54%), cefoperazone+sulbactam n=685 (54%), aminoglycosides (gentamicin, n=669 (53%), amikacin n=608 (48%), and monobactams (aztreonam n=666 (52%). Decreasing trend was observed only for amikacin 63% to 37%, aztreonam showed similar pattern throughout, while there was an increasing trend of drug resistance in all groups of antibiotics. CONCLUSION Emerging drug-resistant strains of Pseudomonas aeruginosa are probably linked to the injudicious use of antibiotics, leading to ineffective empirical therapy. Therefore, we suggest that culture and antimicrobial susceptibility testing should be done for targeted antimicrobial therapy against Pseudomonas aeruginosa.

False Negativity Of Ziehl-neelsen Smear Microscopy: Is The Scale-up The Worth It In Developing Countries?

OBJECTIVE To evaluate the false negative results of Ziehl-Neelsen (ZN) smear microscopy. STUDY DESIGN Descriptive study. PLACE AND DURATION OF STUDY Mycobacteriology Laboratory, Allama Iqbal Medical College (AIMC) and Jinnah Hospital, Lahore (JHL), Pakistan, from February 2014 to August 2016. METHODOLOGY A total of 3,951 (pulmonary 2,773 and extra-pulmonary 1,178) samples were collected from strong TB suspected patients attending JHL Lahore. Follow-up cases were excluded. Every specimen was processed for ZN smear microscopy, Lowenstein Jensen (LJ) culture. SPSS 21.0 was used; false negative and positive results of ZN smear were calculated keeping LJ culture as gold standard. RESULTS Out of total 3,951 samples, sputum was most frequently found pulmonary sample 48.4% (n=1915), extra- pulmonary samples, pleural fluid and pus samples were most commonly observed samples 12.0% (n=476) and 8.3% (n=329), respectively. Overall false negativity was 23.1% (pulmonary=19.6%, extra-pulmonary=29.2%) (p<0.001), Maximum false negative results were observed in pericardial, synovial, pleural fluids, and pus samples as 40.0%, 38.0%, 33.0% and 32.0%, respectively. CONCLUSION ZN smear microscopy is not a very efficient tool in case of patients with the low mycobacterial load. Therefore, National TB Control programs should consider extending their diagnostic approaches from ZN microscopy to more advanced techniques.

Prevalence of extended-spectrum-β-lactamase-producing Enterobacteriaceae : first systematic meta-analysis report from Pakistan

BackgroundSouth-Asia is known as a hub for multidrug-resistant (MDR) bacteria. Unfortunately, proper surveillance and documentation of MDR pathogens is lacking in Pakistan. The alarming increase in the prevalence of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae is a serious problem. From this perspective, we analysed published data regarding ESBL-producing Enterobacteriaceae in different regions of Pakistan.MethodsA meta-analysis was performed to determine the prevalence of ESBL-producing Enterobacteriaceae in Pakistan. A Web-based search was conducted in electronic databases, including PubMed, Scopus and PakMedi Net (for non-indexed Pakistani journals). Articles published (in either indexed or non-indexed journals) between January 2002 and July 2016 were included in the study. Relevant data were extracted, and statistical analysis was performed using the Metaprop command of STATA version 14.1.ResultsA total of 68 studies were identified from the electronic data base search, and 55 of these studies met our inclusion criteria. Pakistan’s overall pooled proportion of ESBL-producers was 0.40 (95% CI: 0.34–0.47). The overall heterogeneity was significant (I2 = 99.75%, p < 0.001), and significant ES = 0 (Z = 18.41, p < 0.001) was found. OXA, SHV, TEM and CTX-M were the most commonly found gene variants for ESBLs in these studies.ConclusionThe prevalence of ESBL-producing Enterobacteriaceae is high in Pakistan. Little is known about the annual frequency of ESBLs and their prevalence in different provinces of Pakistan. No data are available regarding ESBL frequency in Baluchistan. This underscores an urgent demand for regular surveillance to address this antimicrobial resistance problem. Surveillance to better understand the annual ESBL burden is crucial to improve national and regional guidelines.

Occurrence of extended spectrum β-Lactamase producing gram negative bacteria in tertiary care hospital

P has >90% coverage of BCG vaccination through the EPI program which was introduced in 1965. Despite this high coverage, Pakistan reported an incidence of 231/100,000 population of new TB cases highlighting TB as a major public health issue. This is because of the failure of BCG vaccine to protect against the transmissible form of pulmonary tuberculosis in high TB endemic countries. However, BCG vaccination continues in these countries because BCG confers protection against the disseminated form of TB in children. BCG has also shown some protection against leprosy. Interestingly, BCG has also shown protection against certain forms of cancers. One reason for such non-specific protection may be that BCG activates APCs via PAMPS that interacts with TLRs (2, 4 & 8) which initiate the inflammatory cascade thereby recruiting inflammatory cells to the site of infection and providing maturation signals for neutrophils, macrophages and dendritic cells. Such activation may be crucial for restricting the infection at the initial site. Although activation of the innate arm may not provide subsequent memory, activation of T cells may introduce a certain level of memory response and therefore may form a rational basis for BCG immunotherapy. We have studied the inflammatory cytokine profiles activated in tuberculosis infection in BCG vaccinated endemic setting and shown association of resistance and susceptibility with differing cytokine profiles that may be also responsible for specific and non specific immunity.Background and Aim: Data from Phase I clinical trials showed that protein based pneumococcal vaccines induced poor immune responses. To address this problem the protein needs to be presented in a way that will induce a stronger antibody response that is more likely to protect humans. Our aim was to develop a more immunogenic vaccine by conjugating α-helical region of PspA family 1 and 2, a protein common to all Streptococcus pneumoniae to Vi capsular polysaccharide from Salmonella typhi. The candidate vaccine provides better protection against lethal intravenous challenge with broad range of S.pneumoniae strains.

Impact of putative bacterocins against multidrug resistant clinical isolates

Purpose: Streptococcus agalactiae is a commensal organism but it may cause infection in susceptible hosts including newborns, pregnant or postpartum women. Applying rapid, accurate, and sensitive method for detecting GBS and receiving intrapartum antibiotic prophylaxis (IAP) at delivery have been demonstrated to increase treatment possibility of carrier pregnant women and decrease the rates of GBS vertical transmission to infants. The aim of this study was to evaluate PCR assay targeting 16S rRNA primers compared with conventional culture method for direct detection of GBS in vaginal specimens of pregnant women at 35–37 weeks of gestation in Hamadan.Helicobacter pylori (H. pylori) infection is associated with several diseases including gastritis, gastric ulcer, pancreatic cancer and iron deficiency anemia. Different epidemiological studies reported controversial findings on the association between O blood group and H. pylori infection. This metaanalysis was conducted to verify the association between H. pylori infection and O blood group. Random-effects model was used to pool data on the association between H. pylori infection and O blood group in 18 selected studies. DerSimonian Liard statistic was used to estimate the effect size. Stability of the pooled estimates was assessed by sensitivity analysis. Publication bias was assessed by using funnel plot and Egger’s test. Fourteen of the 18 included studies reported no significant association between H. pylori infection and O blood group. Among ten reviewed studies which were conducted among dyspeptic patients, four showed statistically significant association. However, none of six studies conducted among asymptomatic patients demonstrated statistically significant association. The pooled effect size showed no statistically significant association between O blood group and H. pylori infection (odds ratio (OR) = 1.18, 95% CI [0.95, 1.48]). However, the pooled effect size under stratified meta-analysis turned to be statistical significant among studies conducted in dyspeptic patients (OR = 1.44; 95% CI [1.03, 2.01]). The analysis did not show statistically significant association between H. pylori infection and O blood group among all study participants. However, statistically significant association between H. pylori infection and O blood group was observed in a subset of studies conducted among dyspeptic patients. Caution should be made while interpreting the finding as the severity of dyspepsia is not standardized and different H. pylori strains were not taken into account.History: A 5-year old male was admitted last February 2013 for multiple infections secondary to Severe Combined Immunodeficiency. He was treated with different antibiotics for Mycobacterial, Fungal and Multiple opportunistic Bacterial Infections. Patient complained of gastrointestinal pain and mild diarrhea. The first request for stool culture was made on May 6, 2013 and the Microbiology Laboratory identified the organism by VITEK 2 compact (Biomeriux) as Salmonella Group. Polyvalent slide latex agglutination (Sifin Germany) was used and typed it as Group E Salmonella. Sensitivity results were resistant to all Cephalosporins, Fluoroquinolones, and Aminopenicillins and Penicillins with beta lactamase inhibitor. Carbapenems were all sensitive and attending physician started Imipenem. After 15 days, the second culture was repeated. Salmonella group E was isolated with the same sensitivity pattern but this time gave an intermediate result on Ertapenem. The third stool culture was done after five days. Salmonella group E was isolated with same sensitivity pattern but carbapenems were all reported resistant. Manual ESBL and Modified Hodge tests were performed according to the CLSI and ESCMID guidelines. Both yielded negative. Sample was sent to Milan, Italy for Molecular Typing. Results showed that the organism was positive for the Carbapenemase class KpC. Patient was treated successfully with Colistin.Introduction: Salmonella typhi, S. paratyphi A, S. paratyphi B and S. paratyphi C are the causative agents of typhoid fever. Epidemiologic data on typhoid fever and causative agents in endemic countries is lacking or incomplete with very poor estimates of the number of cases and deaths annually. Drug resistance development in typhoid salmonellae is one of important factors in the epidemiology of the disease.Bacteriocins are well known for their antibacterial activity against multidrug resistant strains (MDRs). Lactobacilli are known friendly bacteria for their antibacterial activities against pathogens. The antibacterial activity of different strains of Lactobacilli was analyzed against multidrug resistant strains (MDRs). Multidrug resistant clinical isolates were selected on the basis of their MAR index. Well-Diffusion assay was used for screening of putative bacteriocins produced by Lactobacillus strains against MDRs.Multidrug resistant strains were selected based on MAR (Multiple antibiotic resistance) index. Five bacteriocins obtained from Lactobacillus strains isolated from commercial products. These bacteriocins showed a strong anti-bacterial activity against selected MDRs. Decrease in zone sizes was observed when putative bacteriocins were treated with heat, SDS and Protinase k. Putative bacteriocins produced by Lactobacilli exhibit significant antibacterial activity against MDRs. The peptidal component of these bacteriocins can be used as an alternative therapy.A resistance is a key medical concern, with antibiotic use likely being an important cause. However, here an alternative route to clinically-relevant antibiotic resistance that occurs solely due to competitive interactions between bacterial cells and in the absence of any antibiotic treatment is described. It is consistently observed that isolates of Methicillinresistant Staphylococcus aureus diversify spontaneously into two distinct, sequentially arising strains. The first evolved strain outgrows the parent strain via secretion of surfactants and a toxic bacteriocin. The second is resistant to the bacteriocin. Importantly, this second strain is also resistant to intermediate levels of vancomycin. This so-called VISA (vancomycinintermediate S. aureus) phenotype is seen in many hard-to-treat clinical isolates. This strain diversification also occurs during in vivo infection in a mouse model, consistent with the fact that both coevolved phenotypes resemble strains commonly found in clinic. The study shows how competition between coevolving bacterial strains can generate antibiotic resistance and recapitulate key clinical phenotypes.R to antibiotics has created a severe public health problem worldwide. Thus, the development of novel antibacterial agents represents an urgent unmet medical need. An alternative approach to antibiotics is the use of antivirulence agents. These compounds do not kill bacteria as antibiotics do but inhibit the production of disease-causing toxins and other virulence factors that impair the ability of the immune system to fight the infection. Prevention of virulence factor secretion would disarm the pathogen of its deadly chemical weapons. However, antivirulence agents do not kill the pathogen. Thus, an infection might recur if the treatment is stopped. Therefore, it might be beneficial in some cases to employ a combination therapy with an antibiotic. Experiments in our laboratory indicate a synergism with beta-lactam antibiotics to which MRSA is resistant in mono therapy. Antivirulence agents sensitize MRSA to beta-lactam antibiotics. This finding opens the door to combination therapy of an antivirulence drug with “old” and inexpensive beta-lactam antibiotics. This approach has the potential to revolutionize the prevention and treatment of bacterial infections.3 Abstract: In the present study six medicinal plants: Allium ursinum (bulb), Anethum graveolens (areal part), Buddleja polystachia (leaf), Croton macrostachys (leaf), Dodonaea anguistifolia (leaf) and Pterolobium stellatum (leaf), which are traditionally used to treat TB and related symptoms in Northern part of Ethiopia, were selected for the study. Crude extracts were prepared from the selected species by maceration using 80% ethanol. Various concentrations (250 mg/ml, 500 mg/ml and 1000 mg/ml) of the extracts were then screened for anti-mycobacterial activity against Mycobacterium tuberculosis H37Rv strain using Micro plate Alamar Blue Assay (MABA). Various concentrations (1, 3, 6, 12.5, 25, 50, 125, 250, 500, 1000 mg/ml) of the extracts from the plant species that showed anti-mycobacterial activity were used to determine their respective Minimum Inhibitory Concentrations (MICs). Only three plants (A. ursinum, D. anguistifolia and P. stellatum) of the screened medicinal plants showed anti-mycobacterial activity. The MIC of A. ursinum and P. Stellatum extract was 250 mg/ml; while that of D. anguistifolia was 12.5 mg/ml. It can be concluded that the present study provided a scientific support for the traditional use of Allium ursinum, Dodonaea anguistifolia and Pterolobium stellatum for treatment of tuberculosis.T prevalence of allergic diseases globally is rising sharply in both developed and developing countries. These diseases include bronchial asthma, allergic rhinitis, food allergy and atopic eczema. They have a tremendous impact on patients and their families reducing their quality of life, and increasing rates of morbidity and mortality in these patients. The economic burden on families and societies through direct and indirect costs particularly that of asthma and allergic rhinitis, is quite considerable. Current management of allergic diseases relies mainly on ameliorating disease severity and preventing complications. The worldwide rise in prevalence of allergic diseases promoted extensive research to determine the potential underlying factors. The role of genetic factors, allergen exposure, pollution, dietary habits, life style changes, microbial agents, has been studied. The parallel rise in prevalence of allergic diseases and use of antibiotics prompted many researchers to study possible association. Multiple studies were published in the last two decades. These evaluated the existence of any association between antibiotic use and risk of development of allergic diseases. Additionally, timing of antibiotic use in relation to patient’s age; type, spectrum-coverage, and dosages of antibiotic used; and other factors were studied. Results of these studies seem inconsistent or contradicting. The possibility of an alteration of gut microbiota by antibiotic use leading to deviation of the nascent intestinal immunity of young infancy towards “pro-allergenic type” is determined. There are vivid efforts to develop strategies for primary prevention of allergic diseases. Modulating this antibiotic long-term effect might be one of these future strategies.Farzana Ferdous1,2, Sumon Kumar Das1, Shahnawaz Ahmed1, Fahmida Dil Farzana1, Anowar Hossain1, Dilruba Ahmed1, Mohammad Abdul Malek1, Khitam Muhsen3, Dilruba Nasrin3, Tamer H Flag3, Yukun Wu3, William C Blackwelder3, Sandra Panchalingam3, James P Nataro4, Karen L Kotloff3, Myron M Levine3 and Abu Syed Golam Faruque1 1International Centre for Diarrheal Disease Research, Bangladesh 2University of Tsukuba, Japan 3University of Maryland School of Medicine, USA 4University of Virginia School of Medicine, USAT persistence and growth of mesorhizobia in soils are negatively impacted by desiccation conditions. Studies were conducted to elucidate the nature of drought tolerance in the bacterium Mesorhizobium ciceri strain Ca181 and to correlate with symbiotic effectiveness. In this study, we used transcriptional analyses of trehalose-6-phosphate synthetase (TPS), glgX, NodC and major chaperone genes (groESL, dnaKJ) to obtain a comprehensive sympathetic of the response of Mesorhizobium ciceri strain Ca181 against drought. Polyethylene glycol used to generate drought stress and strain Ca181 tolerated YEB containing 45% PEG-6000 (PEG; wt/vol) for up to 5 days of incubation at 26°C. Desiccation of cells resulted in the differential expression of these genes, with considerable differentiation of 5 min, 15 min 30 min, 1 hr, 4 hr, 8 hr, 24 hr and 48 hr expressed genes. Upon drought conditions, Ca181 showed variable expression pattern of the trehalose-6-phosphate synthetase (TPS), glgX, NodC and major chaperone genes (groESL, dnaKJ) with relation to time interval. This is the first report on transcriptional analysis of the trehalose-6-phosphate synthetase (TPS), glgX, NodC and major chaperones genes in Mesorhizobium ciceri strain Ca181 under drought conditions, which may contribute to a better understanding the mechanisms of drought tolerance in mesorhizobia.Background: Nowadays, increased burden of multidrug resistant Enterobacteriaceae causing UTI compounded by harboring carbapenemase producing strains such as E. coli and K. pneumoniae becomes a serious threat to public health. Carbapenemase producing Enterobacteriaceae expresses enzymes that can break down the antibiotic carbapenem, which is the last resort, antibiotic to treat MDR strains. There are growing evidences of increasing prevalence of MDRE in different part of the world; however, data about the incidence of CPE in is not documented and this is presumed to be first of its kind in Ethiopia.