A Decade of an Underestimated Nosocomal Pathogen- Acinetobacter In a Tertiary Care Hospital in Punjab.

The present study was designed to know the prevalence of Acinetobacter in various clinical samples, their characterization, antibiotic susceptibility pattern and relevance in various clinical samples in Christian Medical College and Hospital, Ludhiana. Out of 3024 samples including pus, body fluids, blood, urine, drain tips, catheter tips and other appropriate samples, Acinetobacter was isolated in 255 (8.4%) samples. 66.6% isolates were sensitive to amikacin and 95% to cefaperazone/ sulbactam combination. This drug resistant nosocomial infection can be minimized to some extent by judicial use of antibiotics and adopting proper infection control measures.

Dengue fever--an emerging viral fever in Ludhiana, North India.

The present study was undertaken to determine the seroprevalence of dengue fever and dengue haemorrhagic fever (DHF) in patients attending medical clinics or admitted in ICU with febrile signs and symptoms of heamorrhages. 168 (39.4%) out of 426 samples were tested positive for IgM antibodies. Of the 168 positive cases 159 were detected during the months of October and November 2005. Early detection of DHF/DSS can go a long way in managing these patients and to reduce morbidity and mortality specially in DHF and DSS cases.

Recurrence of Dengue Epidemic in Ludhiana-2003

Dengue with its severe manifestations- Dengue haemorrhagic fever(DHF) and Dengue shock syndrome(DSS) is now becoming an increasing threat in many parts of the world. An epidemic of febrile illness with haemorrhagic manifestations broke out in Ludhiana from September-November 2003. Serological investigations were conducted to find out the etiology of the febrile illness. Serum samples were collected from all patients coming to the hospital with acute symptoms and tested by ELISA for anti-dengue IgM antibodies. Of the 2309 samples tested, a total of 586 samples were positive for antidengue IgM antibodies and another 98 samples were reported to be in the grey zone. With epidemics occurring in the recent past both in 1996 and 1999, the febrile illness was serologically concluded to be dengue hemorrhagic fever.

Cell adherence--a determinant of virulence in Yersinia enterocolitica.

The adherence of pathogenic bacteria to eukaryotic cells plays a central role in their ability to colonize the mucosal epithelial surfaces. The adherence by Y. enterocolitica to the mucosal surface of the gut is the initiating event leading to penetration of mucosa. Adhesion of 10 probable pathogenic and one non-pathogenic isolate was studied using ileum and colon epithelial cells of mouse for 90 minutes. Adhesion study revealed that isolates of Y. enterocolitica had a good adhesive property while non pathogenic showed negligible adherence. All isolates showed better adherence to colon epithelial cells. The organism continued to be excreted in faeces up to 8-10 days after oral feeding. Adhesion positive isolates were found to be virulent when tested in mice for diarrhoea and death. Adhesion was found to be thermoregulated.

Histopathological and ultrastructural alterations of induced Yersinia enterocolitica infection in mice.

Yersinia enterocolitica is an enteric bacterium and infections by this organism are mostly foodborne. It has been implicated to cause enterocolitis, terminal ilitis. diarrhoea, mesenteric lymphadenitis and arthritis in man. Due to paucity of information regarding histopathological and specially ultrastructural alterations in tissues affected, this study was planned with mice as the experimental model. Nine pathogenic Y.enterocoliticaisolates were used to infect 80 albino mice by oral and intraperitoneal route. Pathological alterations were studied by light and electron microscopy. Histopathological examination of intestines showed severe edema, purulent enteritis, goblet cell hyperplasia infiltration of mononuclear cells, thickening of mucosa and necrosis of the tips of villi. Liver showed congestion, hepatocellular degeneration and necrosis, atrophy of hepatocytes and microabcesses. The lungs revealed congestion, edema, haemorrhage and purulent ronchopneumonia, while kidneys showed mild necrotic changes and bacterial emboli in glomeruli. Ultrastructural changes were indicative of mitochondrial degeneration and their loss in kidneys, membranous degeneration with formation of myelin figures in lungs and disorganization, disruption and bleb formation of microvilli in intestines. Y.enterocolitica caused significant histopathological and ultrastructural alterations in experimentally infected mice. Variation in pathogenicity of different strains of Y.enterocolitica was also observed.