Changing characteristics of Vibrio cholerae: emergence of multidrug resistance and non-O1, non-O139 serogroups.

The serogroups and antimicrobial susceptibility patterns of V. cholerae isolated in Hubli, India during the years 2000 to 2004 were monitored. A total of 256 V. cholerae isolates were obtained during the study period, of which 129 (50.4%) belonged to serogroup O1 while the O139 and non-O1, non-O139 serogroups constituted 61 (23.8%) and 66 (25.8%) isolates, respectively. V. cholerae O1 Ogawa was the predominant isolate during the first 2 years of the study. However, this was replaced by V. cholerae non-O1, non-O139 serogroups in the following years. The V. cholerae, which was susceptible to most enteric antimicrobials in 2000, was found to be multidrug resistant in subsequent years, with the development of fluroquinolone resistance since 2002. Surveillance of the epidemiological and microbiological characteristics of V. cholerae provides useful information for managing cholera cases. The V. cholerae non-O1, non-O139 serogroups coupled with multiple antimicrobial resistance may form a group of emerging diarrheal pathogens in the tropics.

Extended spectrum beta lactamase producing Klebsiella pneumoniae in neonatal intensive care unit.

OBJECTIVE: As infections due to Extended Spectrun beta Lactamase (ESbetaL) producing Klebsiella pneumoniae were increasing in the NICU at Karnataka Institute of Medical Sciences Hospital, Hubli, India, the present study was carried out to identify any environmental sources and the mode of transmission. METHODS: Environmental samples from various sites were collected monthly for a period of six months. RESULTS: ESbetaL producing K. pneumoniae were isolated from all the sites except room air at least on one occasion. ESbetaL producing K. pneumoniae was always isolated from one of the incubators, medicine trolley and sink; while at least one of the health care workers carried it in the hands four out of six times tested. ESbeta L producing K. pneumoniae with similar antibiogram were also isolated from the clinical samples obtained from the neonates. CONCLUSION: Widespread use of third generation cephalosporins as a pre-emptive antibiotic for suspected cases of septicaemia may have contributed to emergence of ESbetaL producing K. pneumoniae in addition to other risk factors. ESbetaL producing K. pneumoniae have extensively colonised the environment of the NICU. Transmission of these pathogens to the neonates has probably occurred through the healthcare workers. Efforts to improve hand hygiene among the healthcare workers and mothers are urgently needed.

Methicillin resistant Staphylococcus aureus infections-implications in hospital infection control.

BACKGROUND: A significant part of nosocomial infections are caused by methicillin resistant Staphylococcus aureus (MRSA). Nosocomial MRSA are known to be multidrug resistant and thus difficult to treat. METHODS: A 2 year study was conducted between January 2001 and December 2002 at Karnataka Institute of Medical Sciences Hospital, Hubli to assess the prevalence of MRSA and its antibiotic susceptibility pattern in various wards. RESULTS: S. aureus was isolated from 714 patients, 283 (37.53%) of which exhibited methicillin resistance. Although these MRSA were multidrug resistant in all the wards, the problem was more severe in NICU and orthopedic wards. CONCLUSION: The results highlight the need for effective implementation of infection control measures in the hospital. There is a need for the judicious use of antimicrobial agents in the hospital and outside as their indiscriminate use can exert pressure in selecting out MRSA and other multidrug resistant organisms.

Neonatal sepsis caused by Salmonella enterica serovar Weltevreden.

Salmonella enterica serovar Weltevreden is an uncommon cause of gastroenteritis occurring worldwide. For the first time, we report 2 cases of neonatal sepsis caused by S. Weltevreden from Hubli, India. In the first case, the neonate had features of septicemia and S. Weltevreden was isolated from a blood culture. The other neonate had omplalitis and clinical features of septicemia. S. enterica serovar Weltevreden was isolated from the umbilical swab culture of this neonate. Even though extensive investigations were conducted, the source of infection could not be identified. Both neonates recovered completely after appropriate antibiotic and supportive therapy.

Community-acquired methicillin-resistant Staphylococcus aureus infections in a south Indian city.

There are increasing numbers of reports of community-acquired Staphylococcus aureus being resistant to methicillin. The present study was undertaken as no such reports are available for the developing nations. In a prospective study, between June to December 2001, at the Karnataka Institute of Medical Sciences, Hubli, Karnataka, India, methicillin-resistant S. aureus (MRSA) isolates were tested for clindamycin-susceptibility, a surrogate marker for community-acquired strains. Patients with clindamycin-susceptible isolates were interviewed to determine if they had acquired them in the community and also to identify any risk factors. Of the 116 patients with S. aureus infection, 18.1% had infection with methicillin-resistant strains. Clindamycin-susceptible MRSA accounted for 61.9% of cases. Among these, 46.1% patients were confirmed to have acquired the MRSA from the community, based on inclusion criteria. The community-acquired MRSA were susceptible to multiple antibiotics, as compared to nosocomial isolates. Except for one patient with diabetes mellitus, no other patient had any known risk factor for acquiring MRSA. As significant numbers of MRSA infections are being acquired from the community, treatment options for S. aureus infections may need to be reviewed. Effective infection control programs for the community should be considered to prevent the spread of these infections.

Comparison between conventional and QBC methods for diagnosis of malaria.

Stained blood film examination is a widely used technique for the diagnosis of malaria. Comparison of this technique was made with the QBC method, which is based on fluorescent staining of the blood cells and parasites. Of the 1435 blood samples studied, 57 (3.97%) samples were positive for malarial parasites by QBC method, while only 44 (3.07%) samples were positive by the blood film examination. Plasmodium vivax was detected in 27 (47.37%), P. falciparum in 26 (45.61%) and mixed infection of P. vivax and P. falciparum in 4 (7.02%) cases. Samples with low levels of parasitaemia (QBC grades 1+ and 2+) were often found to be negative by blood film examination. QBC method was easy to perform, had a higher sensitivity and could be interpreted rapidly, as compared to the Leishman stained blood film examination.

Incidence of Vibrio cholerae serogroup O139 infection with low virulence in Hubli, Karnataka (India).

384 stool samples from patients with acute gastroenteritis were processed by standard culture techniques and antibiogram of V. cholerae was performed. Stool samples from 93 (24.22%) patients yielded V. cholerae, 58 (62.37%) of which were V. cholerae, El Tor O1 Ogawa, 31 (33.33%) V. cholerae O139 and 4 (4.30%) V. cholerae non O1 non O139. Of the culture proven cholera cases watery diarrhoea was observed in 79 (84.95%), vomiting in 57(61.29%), muscle cramps in 21 (22.58%) and sweating in 18 (19.35%). Majority of these patients presented with moderate dehydration 57 (61.29%). Mild dehydration was found in 19 (20.43%) and severe dehydration in 17 (18.28%). While majority of patients with O139 infection had mild to moderate dehydration 25 (80.65%), severe dehydration was more common with O1 infection 11 (64.71%). This study reflects the importance of monitoring the V. cholerae by serogrouping, antibiogram typing, which keep on varying constantly.