Efforts to improve diagnosis of bacteraemia by reducing blood culture contamination in an emergency department: strategies and outcome.

OBJECTIVE: To assess the strategies and outcome for reducing blood culture contamination in order to improve the diagnosis of bacteraemia. METHODS: The interventional study was conducted at a tertiary care hospital in Karachi from January 1, 2013, to December 31, 2016. The blood culture contamination data related to the first year of the study was taken as the baseline pre-intervention data. Strategies were planned as intervention for improvement by consolidating training and education in the form of dedicated lectures, practising on mannequins and developing in-house video, replacing povidone with 2% chlorhexidine preparation spray plus 70% isopropyl alcohol swabs and inducting dedicated phlebotomy team whose only responsibility was blood sample collection and minimising the probability of error. RESULTS: In 2013, there were 8868 samples; 7402 in 2014; 6897 in 2015; and 9756 samples in 2016. The contamination rate in 2013 was 8% which went down to 7.75% in 2014, 4.25% in 2015 and 3.9% in 2016. The decline became statistically significant (p<0.001) after implementing a dedicated phlebotomy team in the emergency department. CONCLUSIONS: Apart from teaching and training, the concept of blood culture collection kit with checklist and dedicated blood collection team was found to be vital in reducing blood culture contamination.

Susceptibility pattern of methicillin resistant Staphylococcus aureus to vancomycin and other alternate agents: report from a private sector hospital laboratory.

With increasing prevalence of methicillin resistant Staphylococcus aureus in clinical settings and injudicious use of antibiotics, resistance among MRSA against commonly used antibiotics is increasing. To assess the susceptibility pattern of MRSA against vancomycin, linezolid, tigecycline, rifampicin, fosfomycin fusidic acid, clindamycin, trimethoprim-sulfamethoxazole and teicoplanin, minimum inhibitory concentrations (MICs) for given antimicrobials were performed on 234 MRSA clinical isolates using automated VITEK 2 system. Vancomycin, linezolid, rifampicin, clindamycin, co-trimoxazole and teicoplanin susceptibilities were interpreted according to CLSI breakpoints, while tigecycline, fosfomycin and fusidic acid were interpreted according to BSAC breakpoints. All isolates were found susceptible to vancomycin, tigecycline, teicoplanin and linezolid. Non-susceptibility of the isolates for rifampicin, fusidic acid and fosfomycin was noted for 58(25%). Co-trimoxazole and clindamycin were found less susceptible showing high resistance rates of 61.5% and 42.3%, respectively. Vancomycin resistance was not found, however an increased MIC of 1 mg/ml was observed in about 25% of clinical strains. Increase in vancomycin MICs in MRSA is of concern and alternative antimicrobial options must be evaluated and considered for treatment of MRSA infections. Continuous antimicrobial surveillance is needed to monitor resistance patterns and detect possible emergence of vancomycin non-susceptible isolates.

Pulmonary scedosporiosis mimicking aspergilloma in an immunocompetent host: a case report and review of the literature.

A case of localized lung scedosporiosis is reported here that mimicked aspergilloma in an immunocompetent host. Through this case the importance of considering Scedosporium spp. in differential diagnosis of locally invasive lung infections and fungal ball is highlighted. As it is difficult to differentiate Scedosporium from Aspergillus on clinical grounds, microscopy, radiology and histopathology, this case is further emphasizing the significance of the definitive etiological characterization of Scedosporium through culture or molecular diagnostic tools. Accurate identification of Scedosporium, surgical resection and high-dose voriconazole has been associated with favorable outcome in most reported cases of scedosporiosis.

Cryptococcus neoformans and Streptococcus pneumoniae co-infection in post-traumatic meningitis in a patient with unknown HIV status.

Meningitis is a serious disease associated with considerable morbidity and mortality. Mixed meningeal infections due to bacteria and fungi are exceptionally rare. Here we report a case of meningeal co-infection with cryptococcus neoformans and streptococcus pneumoniae in a patient with unknown human immunodeficiency virus status. Because of the rarity of such cases, stringent screening of every cerebrospinal fluid specimen to exclude the presence of multiple pathogens is imperative. Assessment of patients for immunodeficiencies in case of isolation of an opportunistic organism like cryptococcus is also needed.

Antimicrobial resistance in Salmonella enterica serovar typhi and paratyphi in South Asia-current status, issues and prospects.

The human race owes a debt of gratitude to antimicrobial agents, penicillin and its successors that have saved people from tremendous pain and suffering in the last several decades. Unfortunately, this consideration is no more true, as millions of people are prone to the challenging threat of emergence of antimicrobial resistance worldwide and the menace is more distressing in developing countries. Comparable with other bacterial species, Salmonella enterica serovar Typhi (S. typhi) and Paratyphi (S. paratyphi) have been evolving multidrug resistance (MDR) against a wide array of antibiotics, including chloramphenicol, ampicillin and co-trimoxazole, and globally affecting 21 million people with 220,000 deaths each year. S. typhi and S. paratyphi infections are also endemic in South Asia and a series of antibiotics used to treat these infections, have been losing efficacy against enteric fever. Currently, quinolones are regarded as a choice to treat MDR Salmonella in these regions. Travel-related cases of enteric fever, especially from South Asian countries are the harbinger of the magnitude of MDR Salmonella in that region. Conclusively, the MDR will continue to grow and the available antimicrobial agents would become obsolete. Therefore, a radical and aggressive approach in terms of rational use of antibiotics during treating infections is essentially needed.

ß-Lactamase production and antimicrobial susceptibility pattern of Moraxella catarrhalis isolates: report from Pakistan.

OBJECTIVE: To assess the frequency of ß-lactamase production and antimicrobial resistance in Moraxella catarrhalis isolated from clinical specimens in Pakistan. METHODS: This cross sectional study (January to December 2010) was conducted in clinical microbiology laboratory of Aga Khan University Hospital. A total of 97 clinical respiratory specimens growing Moraxella catarrhalis were included. Frequency of ß-lactamase production and antimicrobial resistance rates against ampicillin, erythromycin, ciprofloxacin and tetracycline were noted by performing minimum inhibitory concentration (MIC). MICs were calculated as MIC50 and MIC90. RESULTS: ß-Lactamase production was detected in 84% of isolates, which correlated well with high MIC of ampicillin. Majority of isolates were susceptible to erythromycin (97%) and tetracycline (96%) with MIC90=0.12 mg/L and MIC90=1 mg/L respectively. All isolates were found susceptible to ciprofloxacin (MIC90=0.06 mg/L). CONCLUSIONS: Result suggests that empirical use of ampicillin should be discouraged while treating respiratory tract infections. This also emphasizes the importance of continuous surveillance in order to detect emerging resistance in Moraxella isolates.

Knowledge and practices of laboratory workers on standardized antimicrobial susceptibility testing and biosafety practices to prevent the spread of superbugs in Pakistan.

A cross-sectional survey using structured questionnaire was conducted to assess practices of microbiological laboratories working with pathogens. Forty-eight laboratory workers (50%) agreed that laboratory methods to detect antimicrobial resistance are not standardized in Pakistan, and 6% of the laboratory workers were not aware of the standardization of antimicrobial susceptibility testing in Pakistan. Reported rates of awareness regarding the role of waste disposal, disinfection, and handwashing in limiting the spread of antimicrobial resistance were 75%, 42%, and 81%, respectively. Our results provide baseline data for planning programs to train, supervise, and improve the operational quality of microbiological laboratories nationwide to prevent the spread of superbugs.

Human ophthalmomyiasis externa caused by the sheep botfly Oestrus ovis：a case report from Karachi, Pakistan

Ocular myiasis due to Oestrus ovis larvae infestation is an eye infection in humans. A case of ophthalmomyiasis externa in a young male from Karachi, Pakistan in winter (December 2012), without history of close proximity to domestic animals or visit to any rural area was reported. The condition is self-limiting and the disease is confined to the conjunctiva. The eye was locally anesthetized and washed with 5% povidine iodine solution. A total number of 27 first instar larvae of Oestrus ovis were removed with fine forceps. The patient received 0.5% moxifloxacin and diclofenac eye drops for one week. His eye was examined after one day, one week and one month and the recovery status was favorable. The present case raise the awareness among ophthalmologists regarding larval conjunctivitis as one of the causes of conjunctivitis and it can occur throughout the year in any season including winter. Moreover, it can occurr in any area either rural or urban with or without close proximity to domestic animals especially in subtropical regions with high parasitic burden.

Mixed Salmonella infection: a report of two cases from the Aga Khan University Hospital, Karachi.

Enteric fever remains a major health problem in the developing world, including Pakistan. Poor sanitation and hygienic conditions are the major predisposing factors. Salmonella infection with different strains in the same patient has rarely been reported previously. We are reporting two cases of bacteraemia with simultaneous detection of two strains of Salmonella in a single episode of infection. In both the cases, 2 different serotypes of Salmonella were causing bacteraemia leading to fever. In highly endemic area, one must be aware of mixed Salmonella infections as inappropriate diagnosis of such infections may lead to treatment failure.

High isoniazid resistance rates in rifampicin susceptible Mycobacterium tuberculosis pulmonary isolates from Pakistan.

BACKGROUND: Rapid new diagnostic methods (including Xpert MTB/RIF assay) use rifampicin resistance as a surrogate marker for multidrug resistant tuberculosis. Patients infected with rifampicin susceptible strains are prescribed first line anti-tuberculosis therapy. The roll out of such methods raises a concern that strains with resistance to other first line anti-tuberculosis drugs including isoniazid will be missed and inappropriate treatment given. To evaluate implications of using such methods review of resistance data from high burden settings such as ours is essential. OBJECTIVE: To determine resistance to first line anti-tuberculosis drugs amongst rifampicin susceptible pulmonary Mycobacterium tuberculosis (MTB) isolates from Pakistan. MATERIALS AND METHODS: Data of pulmonary Mycobacterium tuberculosis strains isolated in Aga Khan University Hospital (AKUH) laboratory (2009-2011) was retrospectively analyzed. Antimicrobial susceptibility profile of rifampicin susceptible isolates was evaluated for resistance to isoniazid, pyrazinamide, ethambutol, and streptomycin. RESULTS: Pulmonary specimens submitted to AKUH from 2009 to 2011 yielded 7738 strains of Mycobacterium tuberculosis. These included 54% (n 4183) rifampicin susceptible and 46% (n: 3555) rifampicin resistant strains. Analysis of rifampicin susceptible strains showed resistance to at least one of the first line drugs in 27% (n:1133) of isolates. Overall isoniazid resistance was 15.5% (n: 649), with an isoniazid mono-resistance rate of 4% (n: 174). Combined resistance to isoniazid, pyrazinamide, and ethambutol was noted in 1% (n: 40), while resistance to isoniazid, pyrazinamide, ethambutol, and streptomycin was observed in 1.7% (n: 70) of strains. CONCLUSIONS: Our data suggests that techniques (including Xpert MTB/RIF assay) relying on rifampicin susceptibility as an indicator for initiating first line therapy will not detect patients infected with MTB strains resistant to other first line drugs (including isoniazid). The roll out of these techniques must therefore be accompanied by strict monitoring ensuring early resistance detection to increase chances of improved patient outcomes.

Inducible clindamycin resistance due to expression of erm genes in Staphylococcus aureus: report from a tertiary care Hospital Karachi, Pakistan.

OBJECTIVE: To assess the frequency of phenotypic expression of inducible resistance of clindamycin due to expression of erm genes, in clinical isolates of Staphylococcus aureus (S. aureus), by double disk diffusion test (D-test). METHOD: This was a cross sectional study conducted in the clinical laboratory of Aga Khan University Hospital, Karachi. A total of 2432, non duplicate clinical isolates of S. aureus, consisting of 1562 methicillin sensitive S. aureus (MSSA) and 870 methicillin resistant S. aureus (MRSA), were selected from February 2007 to January 2008. One hundred and thirty eight isolates of S. aureus were selected based on discordant resistance pattern (erythromycin resistant and clindamycin sensitive) on Kirby Bauer Disk Diffusion test and phenotypic expression of inducible resistance was assessed using D-test. RESULT: Analysis of 2432 isolates showed that 64% (n=1553) were susceptible to both clindamycin and erythromycin by disc diffusion method, while 30% (n=741) showed constitutive resistance (in vitro resistance to both drugs). 6% (n=138) isolates showed clindamycin-erythromycin discordance on disc diffusion (in vitro sensitive to clindamycin and resistant to erythromycin). Among the discordant isolates 72% (n=99) had inducible resistance phenotype detected by D-test and of these 85 isolates (62%) were MRSA. CONCLUSION: Inducible resistance is common in our clinical isolates; D-test (a simple phenotypic test) should be performed on all S. aureus isolates showing clindamycin-erythromycin discordance on disc diffusion, to avoid erroneous reporting resulting in treatment failure.

Clonal dissemination of vanA positive Enterococcus species in tertiary care hospitals in Karachi, Pakistan.

OBJECTIVE: To perform molecular typing of vancomycin resistant Enterococcus spp. (VRE) strains endemic in various hospitals of Karachi, to characterize the mechanism of glycopeptide resistance and assess the genetic relatedness, for understanding its transmission locally. METHOD: This was a cross sectional study conducted in the clinical and research laboratory of Aga Khan University Hospital (AKUH), Karachi, Pakistan from October 2007 to September 2008. Non-duplicate 86 (65 AKUH and 21 non-AKUH) VRE strains were included. Molecular typing of nosocomial isolates of VRE was carried out by using Pulsed field gel electrophoresis (PFGE) and identification of vanA and vanB genes were performed by conventional Polymerase Chain Reaction (PCR). RESULTS: Analysis of PFGE data by Tenover scheme showed single major pulsotype A with its subtypes A1, A2 and A3 present among different tertiary hospitals in Karachi. The dice coefficient of similarity among AKUH, non-AKUH and total 86 (AKUH and non-AKUH) had a value of 90%, 88% and 89% reflecting their clonal relatedness. In all 60/65 (92%) and 19/21 (90%) AKUH and non-AKUH isolates had vanA gene respectively. None had vanB gene. CONCLUSION: Molecular typing suggested that VRE isolates had same clonal origin indicating nosocomial transmission. Institution of strict infection control measures with active surveillance should be taken to avoid its further spread.

A fatal case of gram negative bacterial sepsis associated with disseminated strongyloidiasis in an immunocompromised patient.

We report a fatal case of disseminated strongyloidiasis in a patient with multiple myeloma receiving chemrotherapy. A fifty-seven years old man presented with severe diarrhoea and vomiting, fever, weight loss and dysphagia,due to mouth ulcers. Despite broad-spectrum intravenous antibiotics, albendazole (anti protozoal) and supportive treatment, the patient died of Gram-negative sepsis.