Effectiveness of boiling in eradication of common pathogens in water.

This Prospective analytic study was conducted at the microbiology laboratory of Dr. Ziauddin Hospital to find out minimum temperature and duration required to eradicate common bacterial pathogens from water samples. High concentration (> 1014 cfu/ml) of five common diarrheal pathogens were added to 100 ml water samples and heated till 40 degrees C, 60 degrees C, 100 degrees C, and two samples were further heated at 100 degrees C for 5 and 10 minutes respectively. Another set of samples were contaminated with stool specimen positive for diarrheal pathogens and heated in the similar fashion. Samples were inoculated on culture media to find out the growth of any organisms. All samples heated to 60 degrees C or beyond did not show any growth of bacteria on culture. So it is reliably proved that heating water up to 100 degrees C is sufficient to eradicate common disease causing bacteria even in stool contaminated samples and further heating would not be required.

Lumbar osteomyelitis with Pseudomonas.

Osteomyelitis is the inflammation of bone secondary to infection with pyogenic organisms. Pseudomonas aeruginosa is usually associated with nosocomial infections and due to its ability to acquire resistance to almost all antibiotics, infections with Pseudomonas pose a great challenge to the physicians. A number of new synergistic combinations have been used in order to treat these organisms and one of the methods is to combine chemicals with systemic antibiotics. In this case we represent a successful eradication of multidrug resistant Pseudomonas using a combination of acetic acid and systemic antibiotics.

Antimicrobial susceptibility pattern of clinical isolates of methicillin resistant Staphylococcus aureus.

OBJECTIVE: To study the antimicrobial susceptibility pattern of MRSA isolates from patients in a tertiary care hospital. METHODS: This was in-vitro study on MRSA isolates received from clinical samples in the department of microbiology during one year (March 2004-February 2005). All samples were processed by conventional method using sheep blood agar, MacConkey's agar and Chocolate agar plates. Staphylococci were identified by catalase, coagulase and D'nase tests. Antimicrobial susceptibility testing of all isolates was performed on Mueller-Hinton agar plates by modified Kirby Bauer's Disc Diffusion method. The disc used Oxacillin (1 microg), Cephalexin (10 microg), Ofloxacin(5 microg), Fusidic acid (10 microg), Penicillin (10 microg), Vancomycin (30 microg), Erythromycin (15 microg), Gentamicin (10 microg), Teicoplanin (30 microg), Amikacin (30 microg) and Clindamycin (2 microg). RESULTS: Our results indicate that out of 190 positive isolates of S. aureus, 82 (43%) were found to be MRSA. These strains were also resistant to many other antistaphylococcal antibiotics. CONCLUSION: A total of 82 (43%) MRSA were isolated from various clinical samples. Pattern of first line antistaphylococcal antibiotics is changing. Antimicrobial susceptibility testing is crucial in the treatment of these patients.

Cephalosporin resistant Shigella flexneri from a clinical isolate--a rare finding.

Shigellosis is an important public health problem, especially in developing countries. Antibiotic treatment of dysentery aimed at resolving diarrhea or reducing its duration, and to prevent transmission to other close contacts. Isolates with resistance to first line drugs have been reported throughout world, third generation cephalosporins and quinolones are mainstay of treatment. Shigella flexneri resistant to third generation cephalosporins in a clinical isolate is a rare finding, and this has been reported for the first time in Pakistan.

Frequency of isolation of shigella serogroups/serotypes and their antimicrobial susceptibility pattern in children from slum areas in Karachi.

OBJECTIVES: To assess the frequency of serogroups and serotypes, as well as the antimicrobial susceptibility pattern of Shigella species isolated from known cases of diarrhoea and dysentery from Karachi, Pakistan. METHODS: A cross-sectional study was conducted between January 2002 and March 2003 at Aga Khan University on stool samples received from children with diarrhoea and dysentery from four low socio-economic areas (Sultanabad, Rehri Goth, Hijrat and Sherpao colony) of Karachi. Stool samples yielding growth of Shigella species, were further identified for serotypes by slide agglutination. Antibiotics susceptibility was performed by Kirby Bauer disk diffusion method. RESULTS: Out of 4688 stool samples received, 193 (4.1%) were positive for Shigella species. Shigella flexneri was the predominant serogroup (58%) followed by Shigella sonnei (16%), Shigella boydii (15%) and Shigella dysentriae being the least common (11%). A number of serotypes were isolated in each serogroup, 8 serotypes in S. flexneri, 8 serotypes in S. dysenteriae, 9 serotypes in S. boydii, and Phase 1 & 2 were found in S. sonnei. 17% isolates remained non-serotypeable. All isolates were susceptible to Ofloxacin and Ceftriaxone, high rate of resistance was observed in Cotrimoxazole (87.75%) and Ampicillin (55.5%). Emerging resistance against Nalidixic acid (39%) was observed. CONCLUSION: Shigella still accounts for a significant proportion of bacillary dysentery in many tropical and subtropical countries. Serotype identification can help in devising strategies such as development of effective vaccine for controlling this problem. Increasing antibiotic resistance against commonly prescribed drugs signify that treatment options have become difficult in cases of severe dysentery.