First-trimester bleeding characteristics associate with increased risk of preterm birth: data from a prospective pregnancy cohort

BACKGROUND

Prior evidence linking first-trimester bleeding with preterm birth (PTB, <37 weeks gestation) risk has been inconsistent and may be biased by subject selection and/or incomplete documentation of bleeding episodes for all participants. Prior studies have not carefully examined the role of bleeding characteristics in PTB risk. In the present study, we estimate the association between first-trimester bleeding and PTB in a non-clinical prospective cohort and test whether bleeding characteristics better predict risk.

METHODS

Women were enrolled in Right from the Start (2000-2009), a prospective pregnancy cohort. Data about bleeding and bleeding characteristics were examined with logistic regression to assess association with PTB.

RESULTS

Among 3978 pregnancies 344 were PTB and 3634 term. Bleeding was reported by 986 (26%) participants. After screening candidate confounders, only multiple gestations remained in the model. Bleeding associated with PTB [odds ratio (OR)(adjusted) = 1.40, 95% confidence interval (CI) 1.09-1.80]. Risk did not vary by race/ethnicity. Compared with non-bleeders, PTB risk was higher for bleeding with red color (OR(adjusted) = 1.92, 95% CI, 1.32-2.82), for heavy episodes (OR(adjusted) = 2.40, 95% CI 1.18-4.88) and long duration (OR(adjusted) = 1.67, 95% CI 1.17-2.38).

CONCLUSIONS

Bleeding associated with PTB was not confounded by common risk factors for bleeding or PTB. PTB risk was greatest for women with heavy bleeding episodes with long duration and red color and would suggest that combining women with different bleeding characteristics may affect the accuracy of risk assessment. These data suggest a candidate etiologic pathway for PTB and warrant further investigation of the biologic mechanisms.

Genetic regulation of the ramA locus and its expression in clinical isolates of Klebsiella pneumoniae

Tigecycline resistance has been attributed to ramA overexpression and subsequent acrA upregulation. The ramA locus, originally identified in Klebsiella pneumoniae, has homologues in Enterobacter and Salmonella spp. In this study, we identify in silico that the ramR binding site is also present in Citrobacter spp. and that Enterobacter, Citrobacter and Klebsiella spp. share key regulatory elements in the control of the romA-ramA locus. RACE (rapid amplification of cDNA ends) mapping indicated that there are two promoters from which romA-ramA expression can be regulated in K. pneumoniae. Correspondingly, electrophoretic binding studies clearly showed that purified RamA and RamR proteins bind to both of these promoters. Hence, there appear to be two RamR binding sites within the Klebsiella romA-ramA locus. Like MarA, RamA binds the promoter region, implying that it might be subject to autoregulation. We have identified changes within ramR in geographically distinct clinical isolates of K. pneumoniae. Intriguingly, levels of romA and ramA expression were not uniformly affected by changes within the ramR gene, thereby supporting the dual promoter finding. Furthermore, a subset of strains sustained no changes within the ramR gene but which still overexpressed the romA-ramA genes, strongly suggesting that a secondary regulator may control ramA expression.

Molecular and epidemiological characterisation of clinical isolates of carbapenem-resistant Acinetobacter baumannii from public and private sector intensive care units in Karachi, Pakistan

The purpose of this study was to identify molecular and epidemiological characteristics of hospital-acquired carbapenem-resistant Acinetobacter baumannii (CRAB) from two different intensive care unit (ICU) settings in Karachi, Pakistan. A cross-sectional study was performed in the adult ICUs of a private sector tertiary care hospital (PS-ICU) and of a government sector hospital (GS-ICU) between November 2007 and August 2008. Deduplicated CRAB isolates from clinical specimens were examined for carbapenemase and class 1 integrase genes. Isolates were typed using sequence-based multiplex polymerase chain reaction, pulsed-field gel electrophoresis (PFGE) and variable number tandem repeat (VNTR). A total of 50 patients (33 from PS-ICU and 17 from GS-ICU) were recruited. There were statistically significant differences between patients in the two ICUs in terms of mean age, comorbidities, the presence of central venous pressure lines, urinary catheters, and average length of stay. bla(OxA-23-like) acquired-oxacillinase genes were found in 47/50 isolates. Class 1 integrase genes were found in 50% (25/50) of the organisms. The majority of isolates belonged to strains of European clones I and II. PFGE typing grouped the isolates into eight distinct clusters, three of which were found in both hospitals. Most of the isolates within each PFGE cluster shared identical or highly similar VNTR profiles, suggesting close epidemiological association. Irrespective of differences in risk factors and infection control policies and practices, the extent of clonality among CRAB isolates was very similar in both ICU settings.

Cohort analysis of directly observed treatment outcomes for tuberculosis patients in urban Pakistan

BACKGROUND

This quasi-experimental cohort study aimed to evaluate World Health Organization (WHO) defined tuberculosis (TB) treatment outcomes for patients under directly observed treatment at a health facility (clinic DOT) or at home (family DOT) in urban Pakistan.

METHODS

We enrolled 582 sputum smear-positive TB patients being treated by either clinic DOT (n = 295) or family DOT (n = 287) in 11 treatment centres. Patients and/or family members were interviewed for baseline measurements. WHO-defined treatment outcomes were evaluated at the end of treatment. Proportions of 'cured' patients were computed. A log-binomial model was used to evaluate the associations of various factors with 'cured' status.

RESULTS

The proportion of 'cured' patients was respectively 66% and 34% in the clinic DOT and family DOT groups (risk difference 0.32; 95%CI 0.24-0.39). Patients on clinic DOT were more likely to achieve cure (adjusted relative risk [RR(adj)] 1.85; 95%CI 1.43-2.39) than those on family DOT, as were patients satisfied with their health care worker's attitude (RR(adj) 5.73; 95%CI 2.54-12.96).

CONCLUSION

Clinic DOT nearly doubled the proportion of cured patients compared to family DOT. Efforts to improve care-provider attitudes to enhance patient satisfaction, and effective implementation of the WHO's public-private mix approach, may enhance TB control in this and similar settings.

Cementless bipolar hemiarthroplasty in femoral neck fractures in elderly

BACKGROUND

Cemented hip arthroplasty is an established treatment for femoral neck fracture in the mobile elderly. Cement pressurization raises intramedullary pressure and may lead to fat embolization, resulting in fatal bone cement implantation syndrome, particularly in patients with multiple comorbidities. The cementless stem technique may reduce this mortality risk but it is technically demanding and needs precise planning and execution. We report the perioperative mortality and morbidity of cementless bipolar hemiarthroplasty in a series of mobile elderly patients (age >70 years) with femoral neck fractures.

MATERIALS AND METHODS

Twenty-nine elderly patients with mean age of 83 years (range:71-102 years) with femoral neck fractures (23 neck of femur and 6 intertrochanteric) were operated over a 2-year period (Nov 2005-Oct 2007). All were treated with cementless bipolar hemiarthroplasty. Clinical and radiological follow-up was done at 3 months, 6 months, 12 months, and then yearly.

RESULTS

The average follow-up was 36 months (range 26-49 months). The average duration of surgery and blood loss was 28 min from skin to skin (range, 20-50 min) and 260 ml (range, 95-535 ml), respectively. Average blood transfusion was 1.4 units (range, 0 to 4 units) Mean duration of hospital stay was 11.9 days (7-26 days). We had no perioperative mortality or serious morbidity. We lost two patients to follow-up after 12 months, while three others died due to medical conditions (10-16 months post surgery). Twenty-four patients were followed to final follow-up (average 36 months; range: 26-49 months). All were ambulatory and had painless hips; the mean Harris hip score was 85 (range: 69-96).

CONCLUSION

Cementless bipolar hemiarthroplasty for femoral neck fractures in the very elderly permits early return to premorbid life and is not associated with any untoward cardiac event in the perioperative period. It can be considered a treatment option in this select group.

Use of p-nitrobenzoic acid in 7H10 agar for identification of Mycobacterium tuberculosis complex: a field study

We report the efficiency and cost-effectiveness of p-nitrobenzoic acid (PNB) testing in Middlebrook 7H10 agar medium for the identification of Mycobacterium tuberculosis complex (MTC). PNB-7H10 was compared with PNB-MGIT and BACTEC-NAP using 200 clinical mycobacterial isolates. PNB-7H10 showed 100% agreement with PNB-MGIT and BACTEC-NAP tests, and reduced the cost of PNB-MGIT test by 80%. PNB-7H10 agar is therefore an effective alternative to the costly PNB-MGIT and BACTEC-NAP tests, especially in resource-poor settings.

Infection control education: impact on ventilator-associated pneumonia rates in a public sector intensive care unit in Pakistan

We describe efforts towards introducing infection control (IC) practices and establishment of antimicrobial resistance (AMR) surveillance in a public sector hospital in Pakistan. The study was conducted in an eight-bed intensive care unit. IC principles, introduced through interactive sessions, were used as an intervention and their impact was observed by conducting surveillance for ventilator-associated pneumonia (VAP) before and after the intervention. Respiratory isolates of VAP patients in the period after intervention were screened for AMR, and empiric antibiotic at the time of admission was compared with the antimicrobial sensitivity pattern reported. VAP rates were high in general and declined in the period after intervention, although the difference was not significant. Of 37 VAP patients in the period after intervention, 68% had more than one clinically significant organism isolated from the respiratory specimen. Acinetobacter spp. were isolated from 76% of patients and Pseudomonas aeruginosa from 43%. All Acinetobacter spp. and 72% P. aeruginosa were multidrug resistant. The mean stay of the nosocomially infected patients was significantly higher than for the uninfected group (6.5 vs. 2.1 days, P<0.001). Our study suggests IC education needs to be supplemented by a hospital system that facilitates IC practices and development of surveillance programmes.

Metallo-beta-lactamase-producing clinical isolates of Acinetobacter species and Pseudomonas aeruginosa from intensive care unit patients of a tertiary care hospital

Prompt detection of metallo-beta-lactamase (MBL) producing isolates is necessary to prevent their dissemination. Frequency of MBLs producing strains among multidrug resistant (MDR) Acinetobacter species and Pseudomonas aeruginosa was evaluated in critical care patients using imipenem-EDTA disk method. One hundred MDR Acinetobacter spp. and 42 Pseudomonas aeruginosa were checked for MBL production, from January to June 2001. MBL was produced by 96.6 % of imipenem-resistant Acinetobacter isolates, whereas 100% imipenem-resistant Pseudomonas aeroginosa isolates were MBL producers. Carbapenem resistance in MDR Acinetobacter spp. and Pseudomonas aeruginosa isolates in this study was due to MBLs. This calls for strict infection control measures to prevent further dissemination.

Determination of nickel, copper, zinc and lead in human scalp hair in Syrian occupationally exposed workers by total reflection X-ray fluorescence

The concentrations of Ni, Cu, Zn, and Pb in human scalp hair of 281 individuals working in 10 Syrian industrial plants were determined using co-precipitation by ammoniumpyrolidinedithiocarbamate (APDC) method for total reflection X-ray fluorescence (TXRF) analysis. The results were compared to data obtained for a control group consisted of individuals working at the Syrian Atomic Energy Commission and also to data reported in the literature. The results given by the group of workers in battery plant showed that Pb concentration in human scalp hair samples were higher than those for control group, while some abnormal concentrations were obtained for Cu, Zn and Ni in cables, printing and battery plants, respectively. Normal concentrations of these elements were obtained for hair workers in olive oil, power stations, textile, and iron industrial plants. The relationships of Pb-Pb/Ni and Cu-Cu/Ni were plotted with correlation coefficients of 0.9937 and 0.9014, respectively. In general, the results showed that, the workers who were occupationally exposed to battery industrial pollution are at risk, followed by individuals in printing and cables industries, while the rest of workers in other industries are considered occupationally unexposed.

Co-circulations of two genotypes of dengue virus in 2006 out-break of dengue hemorrhagic fever in Karachi, Pakistan

BACKGROUND

The status of dengue genotypes involved in the recent epidemic out-breaks in Pakistan is not well defined.

OBJECTIVES

We sought to analyze the predominant genotype responsible for the most severe and largest out-break of dengue hemorrhagic fever (DHF) that hit Karachi in 2006.

STUDY DESIGN

Retrospective analysis of stored serum samples for dengue virus genotype by multiplex RT-PCR, anti-dengue IgM, IgG and review of clinical charts of patients admitted to Aga Khan University Hospital.

RESULTS

Viral RNA detection of 250 patients revealed positive results in 185 (74.0%) samples. DEN-2 was predominant genotype (n=104, 56.2%) Dengue specific antibodies were detected in 139 samples of which 81 were classified as primary cases. DEN-2 accounted for these. Within secondary cases, 63.2% were due to DEN-2 (total 57), the rest were positive for DEN-3. DHF (p=0.064) and abdominal pain (p=0.059) were more frequently associated with DEN-2 as compared to DEN-3. None of the samples were positive for DEN-1 or DEN-4.

CONCLUSION

Co-circulation of DEN-2 and DEN-3 was responsible for the 2006 out-break in Karachi. Primary and secondary cases were seen in both groups. Cases with DHF showed marginal association with DEN-2. Introduction of a new serotype (DEN-3) and or a genotypic shift of endemic serotype (DEN-2) are the probable factors for the recent out-break of DHF in this region.

Increased isolation of Vibrio cholerae O1 serotype Inaba over serotype Ogawa in Pakistan

Although the predominant Vibrio cholerae serotype in Pakistan is Ogawa and serotype Inaba is rare, there has been a significant increase in the isolation of Inaba in our referral laboratory in Karachi. This paper reports this observation and further analysis of previous cholera data from 1993 to 2005 to assess the trend of occurrence and resistance pattern of V. cholerae strains. From January to September 2005, 245/3292 (7.4%) specimens yielded growth of V. cholerae. Of these, 243 were serotype Inaba, outnumbering serotype Ogawa. This recent Inaba strain is 100% resistant to cotrimoxazole, 3% resistant to chloramphenicol and not resistant to ampicillin, tetracycline and ofloxacin. This sensitivity pattern is almost similar to that of the previous predominant serotype Ogawa.

Prevalence of primary multidrug resistance to anti-tuberculosis drugs in Pakistan

SETTING

Pakistan ranks sixth in the world in terms of tuberculosis (TB) burden, with a World Health Organization estimated incidence of 181 per 100000, or 286000 new cases annually. Hospital-based data indicate a significant problem of multidrug-resistant TB (MDR-TB) in the country and highlight the need to assess its extent at community level. In this cross-sectional study, sputum samples from 742 untreated newly diagnosed pulmonary TB patients from all over the country were used.

OBJECTIVE

To assess the prevalence of primary drug resistance in Pakistan.

RESULTS

Of 672 culture-positive patients, 76 (11.3%) showed resistance to one or more drugs. Resistance to streptomycin (10 microg/ml) was found in 36 (5.4%) patients, isoniazid (INH) (1 microg/ml) in 51 (7.6%), rifampicin (RMP) (5 microg/ml) in 15 (2.2%), ethambutol (10 microg/ml) in 12 (1.8%) and pyrazinamide in 22 (3.3%) samples. Forty-six (6.8%) of the isolates tested were resistant to a single drug, 10 (1.5%) to two drugs, 12 (1.8%) to three drugs, and 6 (0.9%) to four drugs, while 2 (0.3%) isolates were resistant to all five first-line agents. Primary MDR-TB was 1.8% (n=12) (INH 1 microg/ml, RMP 5 microg/ml).

CONCLUSION

The results of this study show a prevalence of primary MDR-TB in Pakistan of <2%, which needs to be addressed through an effective DOTS strategy.

Dengue outbreak in Karachi, Pakistan, 2006: experience at a tertiary care center

This is the first report of the largest epidemic of dengue hemorrhagic fever (DHF) virus infection (2006) with IgM-confirmed cases from Karachi, Pakistan. Medical records of 172 IgM-positive patients were reviewed retrospectively for demographic, clinical and laboratory data. Patients were categorized into dengue fever (DF) and DHF according to the WHO severity grading scale. The mean+/-SD age of the patients was 25.9+/-12.8 years, 55.8% were males and the hemoconcentration was recorded in a small number of patients [10 (7.0%)]. Male gender [odds ratio (OR)=14.7, P=0.003), positive history of vomiting (OR=4.3, P=0.047), thrombocytopenia at presentation (OR=225.2, P<0.001) and monocytosis (OR=5.8, P=0.030) were independently associated with DHF, but not with DF. Five cases (2.9%) had a fatal outcome, with a male-to-female ratio of 1:4. Three were from a pediatric group (<15 years). Pulmonary hemorrhages, disseminated intravascular coagulation and cerebral edema preceded death in these patients. The results have highlighted significant findings, such as adult susceptibility to DHF, pronounced abdominal symptoms and lack of hemoconcentration at time of presentation in the study population. These findings may play an important role in the case definitions of future studies from this part of the world.

Impact of antibiotic usage on resistance in microorganisms; urinary tract infections with E-coli as a case in point

OBJECTIVES

In this study, we sought to establish a correlation between consumption of flouoroquinolones in our hospital and the emergence of ofloxacin resistant strains of E. coli in the urinary specimens. Data of all urinary samples, received at Aga Khan University Hospital between January 1995 and December 2002, was retrieved and analyzed. Specimens yielding E-coli as an isolate were included in this study.

METHODS

E. coli Isolates showing >103 colonies were identified using standard microbiological techniques. Antibiotic susceptibility of E. coli was tested using Kirby Bauer disc diffusion method. Antimicrobial usage data, obtained through hospital Pharmacy as unit utilized per year for Quinolones in different medical and surgical units was available only for the period of 1997- 2002.

RESULTS

Among 32,722 urinary specimens E. coli (53%) was the most frequent isolate. Steady increase in the number of ofloxacin resistant E. coli was noted, 24% in 1995 to 55% in 2002. Maximum quinolone resistant E. coli have been observed in Medical units, 41% in 1997 increasing to 70% in 2002, followed by Surgery units (35% to 54%) and Pediatrics (12 to 38%). Sharp increase in ofloxacin consumption in our hospital, 1997 (28613 units) to 2002 (96880 units) has been observed. Trends in quinolone resistance correlate significantly with utilization in the same period as shown by linear regression.

CONCLUSION

E. coli resistance against most antibiotics has been on a rise particularly for quinolones. The utilization of quinolones correlates with increasing resistance in our hospitalized patients.

Evaluation of frequency of isolation and trends in antibiotic resistance among Campylobacter isolates over 11 year period

OBJECTIVE

To analyze frequency of isolation and trends in antibiotic resistance among Campylobacter isolates over 11 year period in Microbiology Laboratory, Aga Khan University from the year 1992-2002.

METHODS

Total 52,777 stool specimens were processed during the study period. Enteric pathogens isolated from 8,483 stool samples were further analyzed for frequency of isolation and antimicrobial resistance. Statistical Analysis was done by using descriptive statistics of SPSS version 10. Values were expressed as percentages, mean and rates.

RESULTS

Campylobacter species were third in frequency of isolation with an isolation rate of 24.8%. C. jejuni was the predominant pathogen followed by C.coli. Isolation rate of Campylobacter was higher (45.7%) among children under 2 years of age as compared to other age groups. A steady rise in resistance among Campylobacter isolates against ampicillin; tetracycline and ofloxacin has been noted whereas resistance against erythromycin remained fairly low.

CONCLUSION

The isolation of Campylobacter is higher from stool specimens of children of less than two years of age rendering Campylobacteriosis to be an important cause of gastroenteritis in pediatric population. This study also demonstrates a steady rise in antibiotic resistance in Campylobacter isolates especially against quinolones with fall in resistance against erythromycin throughout the study period.

Crimean-Congo haemorrhagic fever virus: sequence analysis of the small RNA segments from a collection of viruses world wide

Crimean-Congo haemorrhagic fever virus (CCHFv) is a member of the genus Nairovirus in the family Bunyaviridae. It possesses a tripartite, single stranded RNA genome of negative polarity consisting of large (L), medium (M) and small (S) segments. CCHF virus is enzootic in life stock and wild animals in many parts of the Middle East, Asia and Africa and is also recognised in Southeast Europe. Severe disease, manifest as haemorrhagic fever and high mortality rates (up to 50%), is only recognised in humans. We have determined the complete sequence of the small genomic RNA segment from several strains of CCHF virus from outbreaks in Pakistan 2000, Baghdad 1976 and Uzbekistan 1967. Phylogenetic analysis of three datasets of sequences from the small genomic RNA segment available from a range of strains indicates that they can be divided into seven subtypes. Superimposed on this pattern are links between distant geographic locations, pointing to the existence of a global reservoir of CCHFv. In some cases these links may originate from trade in livestock, and long-distance carriage of virus or infected ticks during bird migration.