Impact of Lactobacillus crispatus-containing oral and vaginal probiotics on vaginal health: a randomised double-blind placebo controlled clinical trial.

Health of reproductive tract is tightly associated with balance of microbial communities in this area. Bacterial vaginosis (BV) and vulvovaginal candidiasis (VVC) represent common disturbances of vaginal communities. Vaginal discharge due to BV or VVC is a very frequent reason for visiting gynaecologist. We aimed to evaluate the impact of the novel evidence-based probiotics on BV and VVC patients. The study group included 89 BV and 93 VVC patients (aged 18-50 years) who were recruited into randomised double-blind placebo-controlled two-arm parallel trial. The patients of each diagnosis group received oral or vaginal probiotic capsules, or placebo capsules during 3 months. A probiotic capsule contained two (DSM32717 and DSM32720, in case of BV) or three (DSM32720, DSM32718 and DSM32716, in case of VVC) Lactobacillus crispatus strains. Vaginal, intestinal and general health was monitored weekly by questionnaire. Blood analyses were done in the beginning and at the end of trial. Vaginal samples were collected monthly, microscopic and molecular analyses were performed. The study revealed that both oral and vaginal capsules reduced the signs and symptoms in BV patients. Remarkable improvement was noted in Nugent score, amount and smell of discharge, but also in itching/irritation. Consumption of vaginal probiotics significantly increased the lactobacilli counts in their vagina while mean proportion of some BV-related bacteria decreased. In VVC patients, both oral and vaginal capsules lowered the combined score of two most important symptoms, amount of discharge and itching/irritation. In conclusion, the novel formulations of evidence-based well-focused probiotic L. crispatus strains are effective against BV and VVC being suitable for both vaginal and oral administration. Clinical trial registration: ISRCTN34840624, BioMed Central.

A combination of the probiotic and prebiotic product can prevent the germination of Clostridium difficile spores and infection.

Clostridium difficile infection (CDI) is one of the most prevalent healthcare associated infections in hospitals and nursing homes. Different approaches are used for prevention of CDI. Absence of intestinal lactobacilli and bifidobacteria has been associated with C. difficile colonization in hospitalized patients. Our aim was to test a) the susceptibility of C. difficile strains of different origin and the intestinal probiotic Lactobacillus plantarum Inducia (DSM 21379) to various antimicrobial preparations incl. metronidazole, vancomycin; b) the susceptibility of C. difficile strains to antagonistic effects of the probiotic L. plantarum Inducia, prebiotic xylitol (Xyl) and their combination as a synbiotic (Syn) product; c) the suppression of germination of C. difficile spores in vitro and in vivo in animal model of C. difficile infection with Inducia, Xyl and Syn treatment. The VPI strain 10463 (ATCC 43255), epidemic strain (M 13042) and clinical isolates (n = 12) of C. difficile from Norway and Estonia were susceptible and contrarily L. plantarum Inducia resistant to vancomycin, metronidazole and ciprofloxacin. The intact cells of Inducia, natural and neutralized cell free supernatant inhibited in vitro the growth of tested C. difficile reference strain VPI and Estonian and Norwegian clinical isolates of C. difficile after co-cultivation. This effect against C. difficile sustained in liquid media under ampicillin (0.75 µg/ml) and Xyl (5%) application. Further, incubation of Inducia in the media with 5% Xyl fully stopped germination of spores of C. difficile VPI strain after 48 h. In infection model the 48 hamsters were administered ampicillin (30 mg/kg) and 10-30 spores of C. difficile VPI strain. They also received five days before and after the challenge a pretreatment with a synbiotic (single daily dose of L. plantarum Inducia 1 ml of 1010 CFU/ml and 20% xylitol in 1 ml by orogastric gavage). The survival rate of hamsters was increased to 78% compared to 13% (p = 0.003) survival rate of hamsters who received no treatment. When administered Xyl the survival rate of hamsters reached 56% vs.13% (p = 0.06). In both Syn (6/9, p = 0.003) and Xyl (3/9, p = 0.042) groups the number of animals not colonized with C. difficile significantly increased. In conclusion, the combination of xylitol with L. plantarum Inducia suppresses the germination of spores and outgrowth into vegetative toxin producing cells of C. difficile and reduces the colonization of gut with the pathogen. Putative therapeutical approach includes usage of the synbiotic during antimicrobial therapy for prevention of CDI and its potential to reduce recurrences of CDI.

Safety of a probiotic cheese containing Lactobacillus plantarum Tensia according to a variety of health indices in different age groups.

Safety of the probiotic Lactobacillus plantarum strain Tensia (DSM 21380) was tested in vitro, in semihard Edam-type cheese, in an animal model and after consumption of the probiotic cheese in double-blind randomized placebo-controlled human intervention studies with different age groups. The susceptibility of L. plantarum Tensia to 8 antibiotics, and the presence of tetracycline (tet M, S, O, K, L) genes and class 1 integron was assessed by applying epsilometer-test and PCR-based methods. Production of biogenic amines by the probiotic strain in decarboxylation medium containing 1% of l-histidine, l-glutamine, l-ornithine, l-arginine, or l-lysine and in cheese was tested by gas chromatography. The biosafety of L. plantarum Tensia was evaluated on National Institutes of Health-line mice fed cheese containing Tensia at a concentration of 9.6 log cfu/g for 30 consecutive days. In human intervention trials in adults and the elderly, the effects of different doses of Edam-type cheese and the probiotic bacterium on BW, gut functionality indices, and host metabolism were evaluated. The strain L. plantarum Tensia was susceptible to all tested antibiotics and did not possess the tetracycline resistance-determining genes tet(L), tet(S) and tet(O), nor did it contain the integron (Int1) gene. However, the strain was tet(K) and tet(M) positive. Lactobacillus plantarum Tensia did not produce potentially harmful biogenic amines, such as histamine or cadaverine. The amount of tyramine produced in the cheese environment during ripening and after 15 wk of storage was below the clinically significant content. In the animal model, no translocation of the administered strain or other microbes into the blood or organs of mice was detected. No harmful effect was observed on body mass index, inflammatory markers, or serum lipidograms during human intervention trials with different age groups at a daily dose of 10.3 or 8.17 log cfu/serving for 3 wk. No negative effect on gastrointestinal welfare was observed, but the consumption of 100g/d for 3 wk caused hard stools from the second week of the trial. The content of total lactobacilli increased in feces, and the presence of the ingested probiotic strain was confirmed after the consumption of cheese. Thus, L. plantarum strain Tensia is suitable for generally recognized as safe (GRAS) and qualified presumption of safety (QPS) criteria because it did not have any undesirable characteristics. The regular semihard Edam-type cheese (fat content of 26%) with the probiotic additive at a daily dose of 50 g or in excess (100g) and with a probiotic daily dose of 10 log cfu for 3 wk was safe.

Antimicrobial susceptibility and serogroup/serotype distribution of nasopharyngeal isolates of Streptococcus pneumoniae in healthy Estonian children in 1999-2003.

This study determined nasopharyngeal (NP) carriage rates of Streptococcus pneumoniae among healthy Estonian children, aged 1-7 years, and characterised the serotype/serogroup distribution and antibiotic susceptibility rates. NP swabs were collected from 685 previously healthy children attending 29 day care centres during the winters of 1999-2000 and 2003. The NP carriage rate of S. pneumoniae was 44%. Rates of penicillin and erythromycin non-susceptibility were low (both 6%), but high (67%) rates of co-trimoxazole resistance were found. Among the pneumococcal serotypes identified, 64% were included in or cross-reacted with the licensed heptavalent pneumococcal vaccine.

Antibiotic resistance as an indicator of bacterial chlorhexidine susceptibility.

The antibiotic and chlorhexidine (CHX) susceptibility of 70 distinct clinical isolates: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Staphylococcus aureus (not MRSA), Streptococcus pyogenes and Enterococcus faecalis (10 of each) were tested using minimal bactericidal (MBC) and/or minimal inhibitory (MIC) concentrations. Non-fermentative bacteria tolerated CHX at high concentrations; Gram-positive cocci, especially S. pyogenes, were the most susceptible. We found a good correlation between CHX and antibiotic susceptibility in both MIC and MBC among Gram-negative bacteria, and mainly in MBC among Gram-positive bacteria. Resistance to ciprofloxacin, imipenem, cefotaxime, ceftazidime, gentamicin and aztreonam appeared to indicate increased CHX resistance among Gram-negative bacteria. This finding gives clinicians the ability to predict CHX susceptibility according to routine antibiotic resistance testing.

Antibiotic usage and resistance - trends in Estonian University Hospitals.

The use of antibiotics, type of infections and resistance of prevalent bacteria was surveyed in Tartu University hospitals. The data from two ICUs (1995 and 1998), surgical and internal medicine departments (1998) were compared. Overall antibiotic usage in the ICUs and in the hospital as a whole had increased. There was a significant increase in Gram-positive bacterial infections and a decrease in Gram-negative infections in the ICUs. At the same time, susceptibility to several antibiotics decreased in most of the prevalent Gram-negative aerobes in the ICUs (Acinetobacter spp., Pseudomonas spp., Klebsiella spp.). Exceptions to this were the greater susceptibility of Pseudomonas spp. to gentamicin and Acinetobacter spp. to imipenem. Some changes in the predominant bacterial populations did not correlate to changes in antibiotic use.

Distribution of Acinetobacter baumannii in a neurointensive care unit.

In a 1-month prospective case-matched study we found Acinetobacter baumannii was a prevailing microbe simultaneously colonizing respiratory tract and skin of neurointensive care unit patients who stayed in our neurointensive care unit for more than 3 d. A. baumannii was not isolated from healthy case-matched controls. Based on their phenotypic properties and the results of amplified ribosomal DNA restriction analysis the 12 strains of Acinetobacter spp. isolated were identified as belonging to DNA group 2 (A. baumannii). For epidemiological typing, Biolog system results of 95-carbon source oxidation, antibiograms and restriction endonuclease analysis were used. One predominant A. baumannii strain was found in all colonized patients, skin and respiratory tract were found mainly to be colonized with the same strain. The starting point of A. baumannii colonization seemed to vary with the individual patient. Environmental strains were different from patients' strains: they were metabolically more active, more resistant and had a different restriction endonuclease analysis profile.

Influence of aqueous extracts of medicinal plants on surface hydrophobicity of Escherichia coli strains of different origin.

The adhesion of microbes on host cells is of decisive importance in the development of Gram-negative microbe-induced infections and can be influenced by the surface hydrophobicity of the microbial cell. The hydrophobicity of 155 Escherichia coli strains of different origin was determined by the salt aggregation test (SAT). Among the strains isolated from faecal samples of healthy persons only 16.7% showed aggregative properties, whereas among the strains isolated from the urine of patients with pyelonephritis and the faecal samples of calves and pigs with diarrhoea some 40.0%-60.0% were aggregative. The influence of aqueous extracts prepared from bearberry leaves, St. John's wort herbs, wild camomile and marigold flowers on hydrophobicity of 40 E. coli and 20 Acinetobacter baumannii strains was investigated. The decoctions of bearberry and St. John's wort increased remarkably the hydrophobicity of both microbial species. The infusions of wild camomile and marigold completely blocked the aggregative properties of the investigated strains. Bactericidal action was relatively low in the case of bearberry and St. John's wort and completely lacking in the case of wild camomile and marigold. Thus, one of the probable and potentially important action mechanisms of the four medicinal plants studied is their ability to influence the surface characteristics of the microbial cells and thereby their putative virulence properties.

Cell surface properties of Acinetobacter baumannii.

Cell surface properties of 78 strains of Acinetobacter baumannii of different origin (lower respiratory tract, wound, blood and environment) were investigated. The bacterial adhesion to collagen, fibronectin, fibrinogen and vitronectin was detected by particle agglutination assays. Salt aggregation tests were used to determine the cell surface hydrophobicity of isolated A. baumannii strains. We found that A. baumannii strains originating from patients with wound infection and bacteraemia showed significantly lower aggregative properties compared to respiratory and environmental strains. Electron microscopic investigations revealed more fimbriated bacterial cells among the highly aggregative A. baumannii strains. This study demonstrates that the investigated A. baumannii strains can be divided into two different groups according to their cell surface properties and source of isolation, whereas the majority of strains, from the lower respiratory tract and the hospital environment expressed strong adhesive properties.

Outbreak caused by two multi-resistant Acinetobacter baumannii clones in a burns unit: emergence of resistance to imipenem.

Since early 1992 an increased number of tobramycin- and imipenem-resistant Acinetobacter spp. were observed causing colonization, wound infections, and bacteraemias in a burns and plastic surgery unit. This raised the question of whether this outbreak was caused by a single or by multiple Acinetobacter spp. clones. To study this, 97 Acinetobacter spp. isolates from clinical samples from different hospital units as well as isolates from the environment and the hands of the staff were characterized by antibiogram, plasmid profile and ribotyping. Two dominant multi-resistant A. baumannii clones were identified; one of them was sensitive to polymyxin B only. There was a close correlation between the results obtained by plasmid profiling and ribotyping. No common environmental source or significant hand carriage, or spread of these strains outside the unit were detected. The burns patients were the most likely reservoir, and strain transmission occurred in spite of strict control measures.