Etiology and Drug Resistance Pattern of Ventilator Associated Pneumonia in an Iranian 1000- Bed Tertiary Care Hospital.

Aim: The aim of this study was to determine etiology and drug resistance pattern of most frequency isolates of microorganisms responsible for VAP in an Iranian 1000-bed tertiary care hospital in Tehran Iran. Place and Duration: This study was conducted in microbiology laboratory of Milad Hospital in Tehran, Iran from November 2010 to December 2011. Methodology: Ventilator Associated Pneumonia (VAP) was defined as any lower respiratory tract infection that developed 48 hours after mechanical ventilation. Tracheal aspirate specimens were collected and processed according standard microbiological procedures. Bacterial identification and susceptibility testing were performed using disk diffusion standard procedures as recommended by CLSI. Results: One hundred and one patients developed at least one episode of nosocomial pneumonia were subject of our study. Of 101 patients 61 patients were male and 40 female patients. The mean time for hospitalization in ICUs and ventilation duration were 16 and 9, 5 days respectively. Old age, History of previous use of antibiotics and duration of ventilation times were the most important risk factors for VAP. In total 126 microorganisms were isolated from VAP cases. Acinetobacer baumannii with 46 (36.5%) isolates was the predominant organism followed by Staphylococcus aureus with 31 (24. 60% and Pseudomonas aeruginosa with 19 (15%) isolates. Other isolated organisms included Klebsiella pneumoniae and E. coli. The majority isolated organism included Acinetobacter baumannii and Pseudomonas aeruginosa were resistant to many antibiotics including the third generation of cephalosporins and nearly 50% isolates were resistant to amikacin. Colistin was the most effective antibiotic against multidurug resistant (MDR) isolates. We found a high rate of methicillin resistant Staphylococcus aureus (93.54%). All isolates of S. aureus were susceptible to vancomycin. Conclusion: Our study revealed that A. baumannii, S. aureus and P. aeruginosa were the major etiological agents of VAP in our hospital. The majority isolates were resistant to routinely used antibiotics including the third generation of cephalosporins. We also observed a high rate of MRSA among our isolates.

Intraperitoneal inoculation of Haemophilus influenzae local isolates in BALB/c mice model in the presence and absence of virulence enhancement agents.

Purpose:Haemophilus influenzae (Hi), predominantly type b accounts for approximately 4% of cases of community-acquired and nosocomial meningitis, in adults. The objective of this study was to evaluate the pathogenicity of local Hi isolates (type b, f and non-typable) in BALB/c mice in the presence of virulence enhancement agents. Materials and Methods: Three different concentrations of the Hi isolates were inoculated intraperitoneally in BALB/c mice in the presence of 2% hemoglobin and 4% mucin as virulence enhancing agents (VEA). The ability of the isolates to produce bacteremia, the percent survival and lethal dose (LD 50 ) were recorded in different challenge groups. Results: The 3 Haemophilus influenzae type b (Hib) isolates used in study were able to show virulence in BALB/c mice model only in the presence of VEA and their LD 50 decreased significantly when 2% hemoglobin and 4% mucin were used. All survived animals showed bacteremia within 4 h of inoculation which was cleared within 18 h. Significant differences ( P < 0.01) in the virulence and survival percentage of Hib challenge groups were observed based on their dose of inoculation and VEA. None of the isolates were able to induce infection in the absence of VEA. Non-type b isolates failed to produce disease in the mice models even at the highest inoculated dose (10 8 cfu) and in the presence of VEA. Conclusions: BALB/c mice appeared suitable for evaluating the virulence of Hib strains, and 2% hemoglobin with 4% mucin an appropriate concentration for inducing infection in this animal model.

Presence of CTX gene cluster in environmental non-O1/O139 Vibrio cholerae and its potential clinical significance.

Purpose: The aim of this study was to understand the epidemiological linkage of clinical and environmental isolates of Vibrio cholerae and to determine their genotypes and virulence genes content. Materials and Methods: A total of 60 V. cholerae strains obtained from clinical specimens (n = 40) and surface waters (n = 20) were subjected to genotyping using PFGE and determination of their virulence-associated gene clusters. Result: PCR analysis showed the presence of chromosomally located hly and RTX genetic elements in 100% and 90% of the environmental isolates, respectively. The phage-mediated genetic elements such as CTX, TLC and VPI were detected in 5% of the environmental isolates suggesting that the environmental isolates cannot acquire certain mobile gene clusters. A total of 4 and 18 pulsotypes were obtained among the clinical and environmental V. cholerae isolates, respectively. Non-pathogenic environmentally isolated V. cholerae constituted a distinct cluster with one single non-O1, non-O139 strain (EP6) carrying the virulence genes similar to the epidemic strains. This may suggest the possible potential of conversion of non-pathogenic to a pathogenic environmental strain. Conclusions: The emergence of a single environmental isolate in our study containing the pathogenicity genes amongst the diverse non-pathogenic environmental isolates needs to be further studied in the context of V. cholerae pathogenicity sero-coversion.

The role of family configuration in early childhood intellectual development in the context of an extended family system in Pakistan.

CONTEXT: The confluence theory of intelligence by Zajonc and Markus emphasizes that individual intellectual difference of children manifests itself in the context of family configuration. Instead of assuming its generalizability, careful scientific work is required before applying the model to South Asian cultures where, predominantly, an extended family type exists. AIMS: To assess the role of extended family configuration on the child's intellectual development in a South Asian setting. SETTINGS AND DESIGN: A cross-sectional study was conducted on 4-5-year-old preschool children residing in Karachi, Pakistan. MATERIALS AND METHODS: Three hundred and forty-two child and mother dyads were assessed through a validated cognitive psychometric tool and through a structured questionnaire. Children who were registered at the main Mother and Child Health Centres (MCH) of the Aga Khan Health Services, Pakistan (AKHSP) Karachi and who were born between July 1st 1993-June 30th 1994 with traceable birth records at the maternity homes, were considered for this study. STATISTICAL ANALYSIS: Multivariate linear regression models were used to identify the individual effect of family configuration on the intellectual scores. RESULTS: Family configuration variables such as number of co-residents ( P P CONCLUSION: The findings suggest the positive role of co-residents of an extended family environment on the intellectual development in early childhood.

A matched case-control study of risk factors for neonatal tetanus in Karachi, Pakistan.

BACKGROUND: Previous studies have identified various risk factors for neonatal tetanus (NNT) in rural areas of Pakistan. The present matched case control study was conducted to further evaluate these risk factors in an urban setting. AIM: The study was carried out to identify risk factors for NNT in Karachi. MATERIALS AND METHODS: Patients of NNT (n = 125) diagnosed from January 1998 to February 2001 were recruited through a surveillance system of Expanded Programme on Immunization (EPI). Two neighbourhood controls (n = 250) were matched for each case for gender and date of birth of the case. STATISTICAL ANALYSIS: Conditional logistic regression was performed to assess the independent effect of factors associated with NNT. RESULTS: The final multivariable model identified subsequent application of substances on the umbilical cord (adjusted matched odds ratio [adj. mOR] = 5.1 [2.7-9.7]), home delivery (adj. mOR = 1.8; 95% CI: 1.1- 3.1) and illiterate mother (adj. mOR = 1.6; 95% CI: 1.0- 2.0) as risk factors for NNT after adjusting for other variables in the model. Population attributable risk per cent (PAR %) for subsequent cord application was 69% and PAR % for home delivery was 31%. CONCLUSION: Health planners, while formulating control strategies through immunization programmes should also take into account the impact of post-delivery practices, such as 'subsequent cord application' along with pre-delivery practices. Health awareness regarding appropriate post-delivery practices should be promoted and counselling of pregnant women for giving preference to health care setting for delivery is also crucial.

HIV/AIDS knowledge, attitudes and beliefs based prediction models for practices in prison inmates, Sindh, Pakistan.

This study was conducted on prison inmates in Sindh to determine whether HIV/AIDS related knowledge, attitudes and beliefs can predict their practices which risk HIV infection. A pre-designed questionnaire was administered in this cross-sectional study to collect the data on HIV/AIDS related knowledge, attitudes, beliefs, practices and demographic variables in a systematic sample of 3,395 prison inmates during July 1994. The data on responses of inmates to HIV/AIDS related knowledge, attitudes, and beliefs were analyzed and a clear interpretable factor structure emerged for each set of questions labeled as knowledge, attitude and beliefs. Similarly based on responses of inmates to practice questions, three factors emerged and were labeled as heterosexuality, homosexuality and drugs. The standardized factor scores of inmates for each of these six factors were computed and used in further analyses. Multiple linear regression analyses were carried out separately using heterosexuality, homosexuality and drugs factors score as dependent variables to identify if any of the independent variables (demographic variables, knowledge beliefs and attitude) predict these practice factors. The model for heterosexuality explained 23% of the variance and included HIV/AIDS related knowledge, beliefs, age, ethnicity and marital status and duration of imprisonment (F = 84.33, p < 0.001; R2= 23.0). The predictors in the model for homosexuality together explained 10% of the variance and included significant contribution by belief, martial status, ethnicity, education, age and duration of imprisonment (F = 24.76, p < 0.001; R2= 0.10). The model for drugs had significant contributions from HIV/AIDS related beliefs, marital status and ethnicity (F = 20.10, p < 0.001; R2= 0.03). Implications of prevention program based on these results are considered.