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 freqently found pulmonary sample 48.4% [n=1915], extrapulmonary 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

Acinetobacter Spp: Resistance and therapeutic decisions at the turn of the novel millennium

This study was planned to evaluate sample wise isolation and antimicrobial resistant trends of Acinetobacter spp in different departments of a tertiary care hospital. This was a transversal descriptive study, carried out in the clinical microbiology laboratory of the Allama Iqbal Medical College/ Jinnah Hospital, Lahore, Pakistan, during the period of January 2015 to December 2016. Every clinical specimen was processed for bacterial culture and antimicrobial susceptibly testing. A total of 3590 [2015=1780, 2016=1810] clinical specimens were processed. Of the total, only 54.7% were gram-negative, among these Acinetobacter spp were isolated from 10.1% and 16.5% samples respectively in 2015-16 with an overall rate of 24.3%. The highest occurrence of Acinetobacter spp isolates was reported from Intensive care units [ICU] [54%] followed by surgical units [25%] and medical units [16%]. It is noteworthy that ICU and internal medicine showed the highest resistance rates, whereas, lower resistance rate was observed for the outdoor patients [OPD]. Although collistin showed 0% resistant while ceftriaxone, ciprofloxacin, gentamicin, and tigecycline showed 90%, 68%, 66%, 66% and 62% resistance against Acinetobacter spp. respectively. An alarming increase in the resistance rate of meropenem, cefoperazone/sulbactam, piperacillin/ tazobactam, ciprofloxacin, and imipenem was observed from the year 2015 to 2016. This startling resistance acquired by Acinetobacter spp. within a period of one year, represent very limited therapeutic options left for the infections caused by Acinetobacter spp. Unavailability of effective drugs and limited therapeutic options enforce the health care practitioners to prescribe expensive and broad range antibiotics, which may cause harm to the patient. Therefore, it is need of an hour to better understand the antimicrobial patterns and optimize antimicrobial prescription policies for the control of multidrug-resistant Acinetobacter spp

Bugged mobile phones of health care providers could transmit more than just a call

Objective: To evaluate contamination of mobile phones from healthcare workers with nosocomial pathogens

Study Design: Cross sectional study

Place and Duration of Study: Microbiology Section, Pathology Department, Allama Iqbal Medical College, Jinnah Hospital Lahore, from Jul 2016 to Feb 2017

Material and Methods: A total of 257 culture swabs were collected from the mobile phones of HCWs of Jinnah Hospital, Lahore, every samples was processed for bacterial culture following standard protocols. Organisms were identified by colonial morphology, gram staining, and with the help of API 20NE and API 20E

Results: Out of 257 mobile phones, 66 percent [n=169] were contaminated with any 01/>01 bacteria. Most prominent pathogen isolated was coagulase negative staphyloccoi [CoNS] followed by Staphylococcus aureus 34.8 percent and 24 percent respectively. Other microorganisms identified, were Acinetobacter species [12.6 percent] n=29, Bacillus species 10.4 percent [n=24], Enterococcus species 4.8 percent [n=11], Escherichia coli 3.5 percent [n=8], Micrococcus species 3.5 percent [n=8], Diphtheroids 2.5 percent [n=5] Klebsiella species 1.7 percent [n=4], Aspergillus species 1.7 percent [n=4] and Pseudomonas aeruginosa 1.0 percent [n=2.0]. Out of 55 Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus [MRSA] were 36.0 percent [n=20] and methicillin-sensitive Staphylococcus aureus [MSSA] were 64.0 percent [n=35]

Conclusion: In the hospital setting mobile phones should be regularly decontaminated. Moreover, utmost emphasis needs to be paid to hand washing practices among HCWs

Rapid diagnosis of tuberculosis using Xpert MTB/RIF assay - report from a developing country

To evaluate the diagnostic accuracy of the Xpert MTB/RIF assay for the detection of M. tuberculosis in pulmonary and extrapulmonary specimens and to compare it with conventional techniques. During a period of 10 months from December 2012 through September 2013, two hundred and forty five clinically TB suspects were enrolled for Xpert MTB RIF assay. The cohort comprised of 205 suspects of pulmonary TB and 40 of extrapulmonary TB [EPTB]. The 40 EPTB samples included pus aspirated from different sites of the body [n=19], pleural fluid [n=11], ascitic fluid [n=7], pericardial fluid, CSF and urine one each. Ziehl-Neelsen [ZN] Stained smear microscopy, culture on LJ media and Xpert MTB/RIF assay was performed on samples from these patients. M. tuberculosis [MTB] were detected by Xpert MTB/RIF test in 111 [45.3%] out of 245 samples. Of these, 85 [34.7%] were smear positive on ZN staining and 102 [41.6%] were positive on LJ cultures. Rifampicin resistance was detected in 16 [6.5%] patients. Nine out of 19 pus samples [47.3%] were positive for MTB by Gene Xpert, 03 [15.8%] on ZN staining and 04 [21%] on LJ culture. MTB could not be detected in any other extrapulmonary sample. Xpert MTB/RIF is a sensitive method for rapid diagnosis of Tuberculosis, especially in smear negative cases and in EPTB as compared to the conventional ZN staining. Among EPTB cases the highest yield of positivity was shown in Pus samples. For countries endemic for TB GeneXpert can serve as a sensitive and time saving diagnostic modality for pulmonary and EPTB

Pathogens causing blood stream infections; in cardiac patients and their susceptibility pattern from a tertiary care hospital

Blood stream infections [BSI] remain a major cause of debility and death around the world. BSI accounts for 10-20% of all Nosocomial infections. Empirical antimicrobials are based on the susceptibility pattern of the pathogens isolated in a specific institute from time to time. We have conducted this study only on cardiac Patients over two and half years of study duration

Study design: cross sectional study

Settings: microbiology Department, Allama Iqbal Medical College/Jinnah Hospital, Lahore

Study Period: January 2013 to July 2015

Materials and Methods: a total of 5411 blood culture specimens were collected from cardiac patients including patients admitted to cardiology ward, coronary care unit [CCU], pre-operative and post-operative cardiac surgery patients. The bottles containing BHI broth were incubated and were subcultured after 24 hours, 72 hours, 120 hours, and 168 hours on blood and MacConkey agars. Isolates were further identified with the help of Gram staining, biochemical reactions and rapid tests like catalase, oxidase, coagulase, Analytical Profile Index [API] 20E and API 20NE. Antimicrobial susceptibility of the isolate was carried out on Mueller-Hinton agar by Modified Kirby Bauer disc diffusion technique according to the isolate as per recommendations of Clinical and Laboratory Standards Institute [CLSI] guidelines 2013

Results: out of total 5411 patients, 3958[73.14%] were male, 1453[26.85%] were females. Out of total 5411 Specimens, only 486 [8.98%] were positive for bacterial growth. Out of total 486 positive blood cultures, 261 [53.71%] were Gram positive isolates and 225 [46.29%] were Gram negative isolates. Out 486 positive blood cultures, 96 [19.75%] were from cardiology ward, 67 [13.78%] were from CCU, 113 [23.25%] were from pre operative cardiac surgery ward, 210 [43.20%] were from post operative cardiac surgery ward. Among Gram positives, Staphylococcus Species were most common organism isolated from 246 [50.61%] blood culture specimens. Among Gram negatives, Pseudomonas aeruginosa and E.coli were predominant organisms, isolated from 81[16.66%] and 72[14.81%] blood culture specimens respectively

Conclusion: gram Positive isolates were more common as compared to Gram negative isolates. Vancomycin and Linezolid were the most effective drugs among Gram positive isolates. Piperacillin-Tazobactam was most potent antimicrobial against Pseudomonas aeruginosa. For coli forms Tigecycline was most effective drug

Concomitant presence of culture-proven active pulmonary tuberculosis in patients with chronic obstructive pulmonary disease - a hospital based study

Objective: To find out the prevalence of concomitant active pulmonary Tuberculosis [TB] in patients of Chronic Obstructive Pulmonary Disease [COPD] using the gold standard liquid and solid culture media for the detection of acid fast bacillus

Methods: Eighty clinically and radiologically diagnosed cases of COPD of any severity, >/= 40 years of age with no previous history of anti-tuberculous therapy were selected from department of Pulmonology, Jinnah Hospital, Lahore. Detailed demographic profile, clinical symptomatology and history of smoking were recorded. Sputum samples of these patients were subjected to ZiehlNeelsen [ZN] stain and culture on Lowenstein-Jensen [L.J] medium and Mycobacterium Growth Indicator Tube [MGIT] for the detection and isolation of Mycobacteriumtuberculosis [MTB]

Results: Out of 80 COPD patients, 6 [7.5%] were culture positive for acid fast bacillus consistent with active tuberculous infection. The concomitance was more prevalent in elderly, male, smokers. MGIT was a more sensitive and a rapid technique to detect the presence of mycobacterium as compared to LJ culture media and ZN stain

Conclusion: The prevalence of active TB in COPD patients was 7.5%. Detection was improved when liquid culture media was employed for the detection of acid fast bacillus. Regular monitoring and screening of patients with COPD for PTB should be routinely carried out in susceptible cohort to avoid cross spreading of infection and appropriate management