Salmonella Typhimurium pneumonia in a patient with multiple myeloma.

Pneumonia due to non-typhoidal Salmonella is a rarely reported entity. A fatal case of Salmonella pneumonia is reported here where Salmonella Typhimurium was isolated from the endotracheal aspirate and blood culture.

Brevibacterium casei as a cause of brain abscess in an immunocompetent patient.

Coryneform bacteria belonging to the genus Brevibacterium have emerged as opportunistic pathogens. Of the nine known species of Brevibacterium isolated from human clinical samples, Brevibacterium casei is the most frequently reported species from clinical specimens. We report the first case of B. casei brain abscess in an immunocompetent patient successfully treated by surgery and antimicrobial therapy.

Anti-infective properties of Lactobacillus fermentum against Staphylococcus aureus and Pseudomonas aeruginosa.

Surgical wounds and implant-associated Staphylococcus aureus and Pseudomonas aeruginosa infections are often difficult to treat because of limited susceptibility of several of these strains to conventional antibiotics. As a result, there is a constant need for new alternative drugs. The aim of this study was to investigate the antimicrobial properties of Lactobacillus fermentum, a probiotic bacterium, which we have isolated from colonic biopsies. The inhibition of S. aureus and P. aeruginosa growth was evaluated by coincubating with L. fermentum strains. Growth inhibition was tested for several of their clinical isolates using agar well diffusion assays. For biofilm assay S. aureus and P. aeruginosa were grown on the glass slides and in 96-well plates in presence of 2.5 µg/ml culture filtrate of L. fermentum. Biofilms were photographed using confocal microscope or stained with 0.1% crystal violet. Reduction in the cytotoxicity of S. aureus and P. aeruginosa was observed in presence of 2.5 µg/ml L. fermentum-spent media. Using in vitroexperiments, we showed that L. fermentum-secreted compound(s) inhibits the growth, cytotoxicity and biofilm formation of several S. aureus and P. aeruginosa strains. Compound(s) present in the culture supernatant of L. fermentum may have promising applications in treating hospital-acquired infections.

Weissella confusa: a rare cause of vancomycin-resistant Gram-positive bacteraemia.

We describe a case of bacteraemia caused by Weissella confusa in a 48-year-old male who was operated on for adenocarcinoma of the gastro-oesophageal junction and maintained on total parenteral nutrition. Blood cultures were positive for a vancomycin-resistant streptococcus-like organism which was identified as W. confusa by 16S rRNA gene sequencing.

Lactobacillus fermentum isolated from human colonic mucosal biopsy inhibits the growth and adhesion of enteric and foodborne pathogens.

A number of Lactobacillus species are used as probiotic strains in order to benefit health. We have isolated L. fermentum from human colonic mucosal biopsy samples that possess antimicrobial activities against entroinvasive and foodborne pathogens such as Escherichia coli, Salmonella paratyphi A, Shigella sonnei, Staphylococcus aureus, Enterococcus faecalis, Proteus mirabilis, Pseudomonas aeruginosa, and Vibrio sp. In addition to lactic acid, L. fermentum secretes antimicrobial proteinacious compound(s) that was found to be active even at neutral pH (pH 7.0). The compound was sensitive to heat treatment and trypsin digestion. Lactobacillus fermentum inhibited the adhesion of enteropathogens to intestinal epithelial cells in vitro. Isolated cell surface associated proteins (SAPs) from L. fermentum were sufficient for the adhesion exclusions of enteropathogenic E. coli. Our results indicate that L. fermentum produces antimicrobial compounds and SAPs to inhibit the growth and adhesion of enteropathogens, respectively.

Aerobic bacterial isolates from choledochal bile at a tertiary hospital.

We studied the aerobic bacterial isolates from bile and their susceptibilty pattern in patients with biliary tract disease. Samples of bile collected during endoscopic retrograde cholangio pancreatography (ERCP) and surgery, were inoculated on standard media. Bacterial identification and susceptibility were done by standard techniques. A total of 209 samples were cultured, out of which 128 samples showed growth. Total number of isolates obtained was 221. Poly-microbial infection was detected in 67 patients. Predominant aerobic bacterial isolates obtained were Escherichia coli 30% (67), Klebsiella species 23.98% (53), Enterococcus species 12.21% (27). Multi-drug resistance was noted in 57%. Higher resistance rate was noted among Gram negative bacilli for ampicillin (92.4%), cephalexin (82.46%), ciprofloxacin (68.42%), piperacillin (64.33%). Sensitivity to meropenem was 90.64% and amikacin was 76.61%. Gram positive bacteria showed high resistance to gentamicin (39.53%). Sensitivity to ampicillin was 86.05% and penicillin was 81.4%. Vancomycin and teicoplanin showed 100% sensitivity. From our study we conclude that E. coli, Klebsiella species and Enterococcus species are common pathogens infecting biliary tract. Poly-microbial infection and multi-drug resistance warrants culture and sensitivity to guide antimicrobial therapy. We recommend combination of amikacin and ampicillin for empirical therapy at our institution.