Lactobacillus rhamnosus administration causes sepsis in a cardiosurgical patient--is the time right to revise probiotic safety guidelines?

A 24-year-old female patient developed sepsis resulting from preoperative administration of probiotics following an aortic valve replacement. Blood cultures revealed the causative agent to be the probiotic Lactobacillus rhamnosus, which has recently been implicated as an emerging aetiology of infection in those taking probiotics. In the past few years, probiotic use in hospitals has increased greatly. However, there is growing global evidence that the use of probiotics in patients with organ failure, immunocompromised status and dysfunctional gut barrier mechanisms can cause infections. This and other reports show the importance of establishing generally recognized safety guidelines.

Microbiological investigation of a hospital outbreak of invasive group A streptococcal disease in Krakow, Poland.

The present study reports the epidemiological investigations undertaken in one of Krakow's city hospitals regarding the source of infection and the routes of transmission of a group A streptococcus (Streptococcus pyogenes), using fluorescent in situ hybridization as a rapid method for detecting S. pyogenes carriage in the medical personnel involved. Four patients from the gynaecology department and two patients from the surgery department presented with clinical signs of infection. Characteristics of the S. pyogenes strains isolated from patients and from one medical staff member, including the emm gene and superantigens encoding genes, are described. All patients (four confirmed and two probable cases) survived; the operating theatre aid was identified as an S. pyogenes carrier and the source of the infections.

A role of hydrogen peroxide producing commensal bacteria present in colon of adolescents with inflammatory bowel disease in perpetuation of the inflammatory process.

Bacteria in the gut play a central role in the initiation and progress of inflammatory bowel disease (IBD). This study was prepared to elucidate the role in the inflammatory process of the bacterial species which are able to produce hydrogen peroxide, present in samples taken from colon lesions in adolescents with inflammatory bowel disease. Fifty eight adolescents were enrolled into the study from January 2004 to October 2006 in Cracow, Poland. Biopsies and stool samples were collected. Bacteriological examinations and measurements of hydrogen peroxide production by enterococci, streptococci and lactobacilli were performed. For the first time it has been shown here that HP producing bacteria may contribute to increased amounts of hydrogen peroxide in the inflamed mucosa of Crohn's disease and ulcerative colitis patients. Moreover, we have been able to demonstrate an increase of total populations of aerobic bacteria but not anaerobes in the studied samples of mucosa of adolescents with inflammatory bowel disease which is an indirect evidence of higher oxygen tension present in inflamed tissues in IBD. We have also been able to demonstrate the direct relationship between presence of blood in stools of IBD adolescents and increased populations of Enterobacteriaceae but not streptococci in samples of colon mucosa. It is, therefore, possible that different products of Enterobacteriaceae and especially their lipopolysaccharides may also contribute to perpetuation of the chronic colon inflammation.

Effect of hydrogen peroxide of bacterial origin on apoptosis and necrosis of gut mucosa epithelial cells as a possible pathomechanism of inflammatory bowel disease and cancer.

A series of in vitro experiments was arranged to assess effects of different concentrations of H(2)O(2) contained in bacterial cultures on apoptosis and necrosis of HT-29 line cells representing human gut epithelium. On the basis of cytofluorimetric assays it was possible to demonstrate that supernatant of the Lactobacillus strain producing hydrogen peroxide (L. delbrueckii CU/22) was able to induce both apoptosis and necrosis in human epithelial culture cells HT-29. Both effects were more prominent than those visible under influence of supernatant of the non-H(2)O(2)-producing Lactobacillus strain or chemically pure H(2)O(2) at the same concentration used as a control. In the light of this study and also other reports on damaging effects of hydrogen peroxide and superoxide radicals of bacterial origin on colonic cells, commensal bacteria of the human gut producing H(2)O(2) may be involved in pathomechanisms of IBD by perpetuating the inflammatory reaction and increasing apoptosis and necrosis. There is a promise that probiotic preparations containing Lactobacillus bacteria will be successful as adjunct therapy of IBD and it is, therefore, postulated to make a very careful selection of the Lactobacillus strains as candidates for probiotics indicated to ameliorate the course of IBD, before starting clinical trials.

Current status of fungal cell wall components in the immunodiagnostics of invasive fungal infections in humans: galactomannan, mannan and (1-->3)-beta-D-glucan antigens.

Early diagnosis of fungal infections and the implementation of appropriate treatment represent major issues for clinicians, nowadays. Histopathological demonstration of microorganisms in tissue specimens or growth of fungal agents in culture media is still considered the "gold standard", but obtaining such specimens may be difficult. Several groups have investigated serological assays for cell wall elements unique to fungal organisms in serum or other body fluids to improve diagnostics in patients with haematological malignancies or undergoing haematopoietic stem-cell transplantation. In this review we have concentrated on the currently available assays allowing for detection of highly immunogenic components of fungal cell wall: galactomannan, mannan, and also (1-->3)-beta-D-glucan. Rapid serological tests appear to be useful for screening high-risk haematological patients, since they allow for the early diagnosis of invasive fungal infections, including infections with the most common pathogens such as Aspergillus and Candida. Based on current literature, factors increasing the probability of obtaining false-positive or false-negative results detected by each test were also analysed and tabulated.

Critical evaluation of probiotic activity of lactic acid bacteria and their effects.

Probiotics discussed in this paper are evaluated using the WHO/FAO definition from 2001. The authors present a brief description of the normal microbiota of the gastrointestinal tract, discuss probiotics in the aspects of gut immunity and then move to selection of bacterial strains as probiotics. The main issue raised is the critical evaluation of probiotics in randomized clinical trials for conditions such as: infectious diarrhoea; antibiotic associated diarrhoea; inflammatory bowel disease; pouchitis and diverticulitis; H. pylori infection; irritable bowel syndrome. Safety of probiotics is mentioned with respect to susceptible individuals and bacterial translocation. As a conclusion the authors again recall the strain specific actions of probiotics in different clinical situations and that so far probiotics play a role in rotaviral and post antibiotic diarrhoea and pouchitis. An important issue still to be solved in order to confidently recommend probiotics as efficacious therapy is the regulatory aspect of probiotics.

Operative gastric perforation: a rare complication of ventriculoperitoneal shunt.

Complications of ventriculoperitoneal shunts are reported in 24-47 % of cases. These include mechanical malfunction and infection, cerebrospinal fluid collection, shunt migration, and visceral perforation. Intestinal perforation, most commonly colonic, may be associated with meningitis or cerebral abscess. Gastric migration has been previously described as a late complication related to the use of stiff Raimondi coil-spring peritoneal catheters in children with malnutrition and abdominal adhesions. We report a case of operative gastric perforation, a rare complication which was detected prior to development of symptoms.