Grapefruit bioactive limonoids modulate E. coli O157:H7 TTSS and biofilm.

Limonoids are important constituents of the grapefruit and other citrus fruits. Research on health benefits suggests that citrus limonoids may act as anti-cancer, cholesterol lowering, anti-HIV and anti-feedant compounds. However, antimicrobial activities of citrus limonoids are not reported. In the present investigation, limonoids were purified from grapefruit seed and evaluated for their potential to antagonize cell-to-cell communication, biofilm formation and expression of Enterohemorrhagic Escherichia coli (EHEC) type three secretion system (TTSS). The results of the present study suggest that, certain limonoids are inhibitory to the cell-to-cell communication, biofilm formation and EHEC TTSS. Specifically, obacunone demonstrated strong inhibition of EHEC biofilm formation and TTSS. Furthermore, obacunone and other limonoids seem to inhibit the biofilm formation and TTSS in quorum sensing dependent fashion. The results indicate that certain grapefruit limonoids may possibly help in antagonizing the EHEC infection process, and may serve as lead compound in development of new antipathogenic molecules.

Pacing lead endocarditis due to Aspergillus fumigatus.

Invasive aspergillosis is an opportunistic infection with a high mortality rate that usually occurs in the immunocompromised host. Several cases of fungal infections have been reported after cardiac surgery. We present here a case of Aspergillus fumigatus tricuspid valve endocarditis associated with permanent pacemaker leads. Tricuspid valve vegetectomy was done and the pacing leads were also removed. Culture from the excised vegetation grew Aspergillus fumigatus. The patient was started on IV Amphotericin B for eight weeks. The patient was subsequently followed up in the out-patient clinic, and remains afebrile after one year, with no evidence of any vegetation.

Costs associated with hospital-acquired bacteraemia in an Indian hospital: a case-control study.

Studies from around the world have shown that hospital-acquired infections increase the costs of medical care, morbidity and mortality. The aim of this study was to determine cost and attributable mortality associated with hospital-acquired bacteraemia in a tertiary care centre in India. This was a retrospective case-control, cost utility analysis set in the cardiothoracic unit of a 200-bedded tertiary care cardiac hospital. Cases included adult patients who underwent coronary artery bypass graft and/or valve replacement surgery who developed bacteraemia (indicated by positive blood cultures) during postoperative stay (N=24). Controls were age- and sex-matched adult patients who underwent similar procedures but who did not develop bacteraemia (N=48). Data were collected from patient medical records and other administrative databases for cost analysis. Prolongation of hospital stay, attributable mortality and extra costs associated with hospital-acquired bacteraemia were analysed. Statistical analysis was done using Fisher's exact test and unpaired t-test. Patients with hospital-acquired bacteraemia experienced a significantly longer total hospital stay [mean: 22.9 days; 95% confidence interval (CI): 17.2-28.6; P<0.0001], significantly longer ICU stay (mean: 11.3 days; 95% CI: 9.0-13.6; P<0.0001), a significantly higher mortality (mean: 54%; P<0.0001) and cost significantly more (mean: US $14,818; 95% CI: 10,663-18,974; P<0.0001) than controls. We conclude that hospital-acquired bacteraemia significantly increases mortality and costs of hospitalisation in lower income developing countries. Our study demonstrates that costs associated with HAIs are similar between developing and developed countries. Better infection control planning and infrastructure may offset some of these costs.