Investigation of methicillin-resistant Staphylococcus aureus among clinical isolates from humans and animals by culture methods and multiplex PCR

Background

Staphylococcus aureus is responsible for large numbers of hospital-related and community-acquired infections. In this study, we investigated the presence of S. aureus and methicillin-resistant S. aureus (MRSA) in 100 samples from animals (55 cattle, 36 dogs, and 9 cats) and 150 samples from hospitalized human patients. The samples were collected from healthy and diseased animals and from diseased humans and included milk, wound swab, pus, exudates, nasal swab and diabetic ulcer. Initially, S. aureus was isolated and identified by colony morphology, Gram staining, and biochemical tests (catalase and coagulase tests). The S. aureus-positive samples were examined by polymerase chain reaction (PCR) to determine their MRSA status.

Results

Of the 100 animal samples, 29 were positive for S. aureus. Four samples (13.8%) from dogs were MRSA-positive, but samples from cattle and cats were MRSA-negative. Of the 150 human samples we collected, 64 were S. aureus-positive and, of these, 34 (53.1%) were MRSA-positive. Most (28%) of the MRSA samples were isolated from surgical wound swabs, followed by the pus from skin infections (11%), exudates from diabetic ulcers (6%), exudates from burns (4%), and aural swabs (3%). By contrast, a low MRSA detection rate (n = 4) was seen in the non-human isolates, where all MRSA bacteria were isolated from nasal swabs from dogs. The antimicrobials susceptibility testing results showed that S. aureus isolates with mecA genes showed resistance to penicillin (100%), oxacillin (100%), erythromycin (73.5%), ciprofloxacin (70.6%), and gentamicin (67.7%). The lowest resistance was found against ceftazidime, and no vancomycin-resistant isolates were obtained.

Conclusions

We detected S. aureus and MRSA in both human and canine specimens. Isolates were found to be resistant to some of the antimicrobials available locally. MRSA carriage in humans and animals appears to be a great threat to effective antimicrobials treatment. The prudent use of antimicrobials will reduce the antimicrobial resistance. Our findings will help to find the most appropriate treatment and to reduce antimicrobial resistance in the future by implementing prudent use of antimicrobials. Further studies are required to better understand the epidemiology of MRSA human–animal inter-species transmission in Bangladesh.

Electronic supplementary material

The online version of this article (10.1186/s12917-018-1611-0) contains supplementary material, which is available to authorized users.

Anti-phospholipid Antibody Syndrome Presenting as Huge Ascites: A Case Report

Antiphospholipid Syndrome (APS) is characterized by arterial, venous or small vessel thromboses and/or pregnancy morbidity in the presence of persistently elevated titers of antiphospholipid antibodies. Since virtually any organ can be involved, the clinical presentation of APS is very varied. Abdominal manifestations are rare but may be life-threatening, and include Budd-Chiari Syndrome. We report the case of a 26-year-old woman with primary APS, on aspirin treatment, who presented to us at Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh in March 2017 with ascites for which she had been receiving treatment for abdominal tuberculosis. Following clinical and laboratory evaluation, she was diagnosed as a case of Budd-Chiari Syndrome with portal hypertension and initiated treatment with warfarin. There should be a high index of clinical suspicion for Budd-Chiari as a cause of ascites in patients with APS, since early recognition and treatment can significantly improve patients' survival.

Magnetic Resonance Imaging of Cerebral Palsy in the Assessment of Time of Brain Insult

The aim of this cross-sectional study was to find out the role of Magnetic resonance imaging (MRI) in the assessment of time of brain insult in cerebral palsy (CP). The study was conducted in the Department of Radiology & Imaging, Mymensingh Medical College Hospital, Mymensingh and a total number of 35 patients with were enrolled from January 2015 to December 2016. Maximum patients (57.2%) were under five years followed by 34.3% were of 5 to <8 years and 8.7% were of 8 to <12 years of age and mean age was 4.7 years. Majority of the patients were male 28(80%) and female were 7(20%). Among the patients 23(65.7%) came from poor, whereas 11(31.4%) came from middle class and only one (2.9%) from rich socioeconomic group. According to gestational age of the patients, 26(74.3%) were term (≥37weeks) at delivery and rest (25.7%) were preterm (<37 weeks). Delayed cry after birth were present in 32 (80%) patients. Regarding types of cerebral palsy spastic diplegia, spastic quadriplegia, hemiplegia and extrapyramidal were found 3(8.6%), 25(71.4%), 4(11.4%) and 3(8.6%) respectively. Abnormal MRI was reported in 94.2% patients and gave clues to time of insult in 79.9% (excluding the 14.3% miscellaneous findings). The findings were mal-developments (5.7%), periventricular white matter lesions (25.7%), cortical or deep grey matter lesions (48.6%), miscellaneous (14.3%) and normal (5.7%). Brain mal-developments were more seen in term than in preterm born children (5% vs. 0%). Periventricular white matter lesions were seen significantly more in preterm than in term born children (77.8% vs. 3.9%). Cortical or deep grey matter lesions occurred significantly more in term than in preterm born children (60% vs. 20%). Based on the study it can be concluded that Magnetic Resonance Imaging (MRI) can help in the assessment of time of insult to the developing brain in cerebral palsy (CP).

FAST implementation in Bangladesh: high frequency of unsuspected tuberculosis justifies challenges of scale-up

SETTING

National Institute of Diseases of the Chest and Hospital, Dhaka; Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders, Dhaka; and Chittagong Chest Disease Hospital, Chittagong, Bangladesh.

OBJECTIVE

To present operational data and discuss the challenges of implementing FAST (Find cases Actively, Separate safely and Treat effectively) as a tuberculosis (TB) transmission control strategy.

DESIGN

FAST was implemented sequentially at three hospitals.

RESULTS

Using Xpert® MTB/RIF, 733/6028 (12.2%, 95%CI 11.4-13.0) patients were diagnosed with unsuspected TB. Patients with a history of TB who were admitted with other lung diseases had more than twice the odds of being diagnosed with unsuspected TB as those with no history of TB (OR 2.6, 95%CI 2.2-3.0, P < 0.001). Unsuspected multidrug-resistant TB (MDR-TB) was diagnosed in 89/1415 patients (6.3%, 95%CI 5.1-7.7). Patients with unsuspected TB had nearly five times the odds of being diagnosed with MDR-TB than those admitted with a known TB diagnosis (OR 4.9, 95%CI 3.1-7.6, P < 0.001). Implementation challenges include staff shortages, diagnostic failure, supply-chain issues and reliance on external funding.

CONCLUSION

FAST implementation revealed a high frequency of unsuspected TB in hospitalized patients in Bangladesh. Patients with a previous history of TB have an increased risk of being diagnosed with unsuspected TB. Ensuring financial resources, stakeholder engagement and laboratory capacity are important for sustainability and scalability.

Physicians’ Choice in Using Internet and Fax for Patient Recruitment and Follow-up in a Randomized Controlled Trial

Objective: To examine the physicians’ preference between Web and fax-based remote data entry (RDE) system for an ongoing randomized controlled trial (RCT) in Japan.

Methods: We conducted a survey among all the collaborating physicians (n = 512) of the CASE-J (Candesartan Antihypertensive Survival Evaluation in Japan) trial, who have been recruiting patients and sending follow-up data using the Web or a fax-based RDE system. The survey instrument assessed physicians’ choice between Web and fax-based RDE systems, their practice pattern, and attitudes towards these two modalities.

Results: A total of 448 (87.5%) responses were received. The proportions of physicians who used Web, fax, and the combination of these two were 45.9%, 33.3% and 20.8%, respectively. Multivariate logistic regression analyses revealed that physicians 55 years or younger [odds ratio (OR) = 1.9, 95% confidence interval (CI) = 1.1-3.3] and regular users of computers (OR = 4.2, 95% CI = 2.1-8.2) were more likely to use the Web-based RDE system.

Conclusions: This information would be useful in designing an RCT with a Web-based RDE system in Japan and abroad.

First characterization of immunogenic conjugates of Vi negative Salmonella Typhi O-specific polysaccharides with rEPA protein for vaccine development

Efficacious typhoid vaccines for young children will significantly reduce the disease burden in developing world. The Vi polysaccharide based conjugate vaccines (Vi-rEPA) against Salmonella Typhi Vi positive strains has shown high efficacy but may be ineffective against Vi negative S. Typhi. In this study, for the first time, we report the synthesis and evaluation of polysaccharide-protein conjugates of Vi negative S. Typhi as potential vaccine candidates. Four different conjugates were synthesized using recombinant exoprotein A of Pseudomonas aeruginosa (rEPA) and human serum albumin (HSA) as the carrier proteins, using either direct reductive amination or an intermediate linker molecule, adipic acid dihydrazide (ADH). Upon injection into mice, a significantly higher antibody titer was observed in mice administrated with conjugate-1 (OSP-HSA) (P=0.0001) and conjugate 2 (OSP-rEPA) (P≤0.0001) as compared to OSP alone. In contrast, the antibody titer elicited by conjugate 3 (OSPADH-HSA) and conjugate 4 (OSPADH-rEPA) were insignificant (P=0.1684 and P=0.3794, respectively). We conclude that reductive amination is the superior method to prepare the S. Typhi OSP glycoconjugate. Moreover, rEPA was a better carrier protein than HSA. Thus OSP-rEPA conjugate seems to be efficacious typhoid vaccines candidate, it may be evaluated further and recommended for the clinical trials.

Comparative yielding of BACTEC MGIT 960 and GeneXpert MTB/RIF Assay for Rapid Diagnosis of Drug Resistance Tuberculosis from Sputum Specimen

Among communicable disease, tuberculosis is the second leading cause of death worldwide, killing nearly two million people each year. Several diagnostic techniques are currently used to detect mycobacteria in respiratory specimens. Therefore an alternative, rapid and most effective method is required for diagnosis of pulmonary tuberculosis which is relatively more sensitive and specific. A total of 107 sputum samples of suspected TB patients were enrolled attending the National Tuberculosis Reference Laboratory (NTRL), Mohakhali, Dhaka, Bangladesh from July 2014 to July 2015. Liquid culture of 107 sputum samples, yielded 76.63% culture positive and 1.86% contamination was observed. Antibiotic susceptibility test was done for 82 culture positive sputum samples among which 28.04% cases were resistant to both Rifampicin and Isoniazid. GeneXpert assay detected 85.04% M. tuberculosis among which 25.23% were found to be Rifampicin Resistance.

Arthroscopic Anterior Cruciate Ligament Reconstruction with Triplet Autograft of Semitendinosus Tendon

Anterior cruciate ligament (ACL) is the most commonly injured ligament occurs in young adult population, which markedly reduces activity level. Anterior cruciate ligament rupture is a threat to the homeostasis of the knee. So, reconstruction of the ACL is necessary to make them fit and return to their pre-injury activity level. The choice of graft for ACL reconstruction is a matter of debate, with the BPTB graft and quadruple graft of ST-G being the two most popular options. Use of triplet graft of semi-tendinosus tendon alone without sacrificing gracilis is another option. So hypothesis was Arthroscopic ACL reconstruction with triplet autograft of semi-tendinosus tendon alone is an effective procedure. This prospective interventional study was conducted from October 2011 to March 2013 at Dhaka Medical College Hospital, Dhaka, Bangladesh. Fourteen patients who had a unilateral anterior cruciate ligament rupture underwent arthroscopic reconstruction with triplet graft of semi-tendinosus tendon. Accelerated ACL reconstruction rehabilitation protocol was followed and final outcome evaluation done at 24 weeks according to IKDC knee examination form and Lysholm knee scoring scale. Preoperative Lysholm knee score was 52.64 and postoperative score was 90, that shows significant improvement (p<0.05). According to Lysholm knee scoring scale, excellent results (95-100 points) were obtained in 33% patients, good results (85-94 points) in 53% patients, fair and poor (7% each). For arthroscopic ACL reconstruction, choice of semi-tendinosus tendon alone preserving gracilis, comparable outcome as with BPTB/ST-G graft, can be achieved, minimizing the hamstring strength deficit. Moreover gracilis being reserved for future use in revision ACL reconstruction and/or in other reconstructive surgery.

Van Wyk and Grumbach Syndrome: An Unusual Presentation of Hypothyroism

An 18 years-old-girl presented one and half years back with the complaints of short stature, retarded growth, and menorrhagia with sudden severe lower abdominal pain; was diagnosed as bilateral ovarian cysts and underwent bilateral ovarian cystectomy. Later on she was incidentally diagnosed as a case of hypothyroidism when she had been experiencing slowly enlarging left lower abdominal mass with dull ache for the 5 month and then was transferred to the department of Endocrinology for further evaluation. Detailed work up revealed her short stature with obesity, delayed bone age and other features of hypothyroidism which was confirmed by thyroid function testing. She had enlarged left ovary with multiple follicles as shown in ultrasonography. Magnetic resonance imaging (MRI) showed sellar mass which was suspicious of macroadenoma. Levothyroxine replacement was started and she had a dramatic improvement of her problems with disappearance of the ovarian cysts and sellar mass.

Relationship between Echocardiographic Epicardial Adipose Tissue (EAT) Thickness and Angiographically Detected Coronary Artery Disease

Epicardial adipose tissue (EAT) is a particular form of visceral adipose tissue deposited around the heart and there is growing evidence about the physiological and metabolic importance of EAT, especially in the association of cardiovascular risk profiles and the pathogenesis of atherosclerotic coronary artery disease. This observational, cross sectional study was done to determine the relationship between echocardiographic epicardial adipose tissue (EAT) thickness and coronary artery disease (CAD). Total 123 patients with established or suspected coronary artery disease admitted for coronary angiogram in the department of Cardiology of Bangabandhu Sheikh Mujib Medical University (BSMMU) from November 2010 to the end of April 2011 were included in this study. Epicardial adipose tissue (EAT) thickness measurements by echocardiography were compared with coronary angiographic findings. Echocardiographic epicardial adipose tissue (EAT) thickness was significantly higher in patients with CAD in comparison to those with normal coronary arteries (6.67±2.24mm vs. 4.61±1.62mm; p<0.001). Furthermore, EAT thickness increased with the severity of CAD (multi-vessel disease 7.99±2.12mm vs. single vessel disease 5.93±1.97mm; p<0.001). Gensini's score significantly correlated with EAT thickness (r=0.617, p<0.001). Optimum cut-off point (OCP) of epicardial adipose tissue (EAT) thickness as a predictor of angiographic CAD was 6.44mm with 45.31% sensitivity and 92.86% specificity [ROC area 0.756, p<0.001, 95%CI (0.66-0.85)]. Echocardiographic epicardial adipose tissue (EAT) thickness was significantly correlated with the presence and severity of angiographically detected coronary artery disease (CAD).