Investigation of inpatient probiotic use at an academic medical center

Infectious complications of probiotic use: A matched case-control study

In this matched case-control study, we sought to determined the association between probiotic use and invasive infections caused by typical probiotic organisms. The odds of probiotic use in cases were 127 times the odds of probiotic use in controls (95% CI, 6.21-2600). Further research into these rare but severe complications is needed.

Fatal Lactobacillus endocarditis in a patient with transcatheter aortic valve replacement

Lactobacillus species may translocate from the gastrointestinal tract into systemic circulation from ingested probiotics or commensal flora. Their pathogenic potential is still debated. Lactobacillus endocarditis is a rare entity with only around 120 cases reported in the literature. Here, we report the first case of fatal Lactobacillus endocarditis with involvement of a transcatheter aortic valve replacement with the following goals: to reaffirm the pathological significance of Lactobacillus spp, to demonstrate the potential limitations of the modified Duke criteria in diagnosing infective endocarditis of transcatheter aortic valve replacement, and to urge clinicians to aggressively search for and consider empiric treatment for endocarditis in patients with prosthetic valves who develop Lactobacillus bacteraemia.

Lactobacillus acidophilus LB: a useful pharmabiotic for the treatment of digestive disorders

Dysbiosis, a loss of balance between resident bacterial communities and their host, is associated with multiple diseases, including inflammatory bowel diseases (nonspecific chronic ulcerative colitis and Crohn's disease), and digestive functional disorders. Probiotics, prebiotics, synbiotic organisms and, more recently, pharmabiotics, have been shown to modulate the human microbiota. In this review, we provide an overview of the key concepts relating to probiotics, prebiotics, synbiotic organisms, and pharmabiotics, with a focus on available clinical evidence regarding the specific use of a unique pharmabiotic, the strain Lactobacillus acidophilus LB (Lactobacillus boucardii), for the management of gastrointestinal disorders. Since it does not contain living organisms, the administration of L. acidophilus LB is effective and safe as an adjuvant in the treatment of acute diarrhea, chronic diarrhea, and antibiotic-associated diarrhea, even in the presence of immunosuppression.

Probiotics and infective endocarditis in patients with hereditary hemorrhagic telangiectasia: a clinical case and a review of the literature

Background

In the last decades, probiotics have been widely used as food supplements because of their putative beneficial health effects. They are generally considered safe but rare reports of serious infections caused by bacteria included in the definition of probiotics raise concerns on their potential pathogenic role in patients with particular predisposing factors. Patients with hereditary hemorrhagic telangiectasia (HHT) are exposed to infections because of telangiectasias and arteriovenous malformations (AVMs). We describe what is, to our knowledge, the first case of infective endocarditis (IE) caused by Lactobacillus rhamnosus in a patient with HHT. A systematic review of the relevant medical literature is presented.

Case presentation

A patient with HHT and an aortic bioprosthesis was admitted because of prolonged fever not responding to antibiotics. The patient had a history of repeated serious infections with hospitalizations and prolonged use of antibiotics, and used to assume large amounts of different commercial products containing probiotics. Weeks before the onset of symptoms the patient had been treated with nasal packings and with surgical closure of a nasal bleeding site because of recurrent epistaxis. A diagnosis of IE of the aortic bioprosthesis was made. All blood coltures were positive for L. rhamnosus. The patients responded to a cycle of 6 weeks of amoxicillin/clavulanate plus gentamicin. A systematic review of IE linked to consumption of probiotics, and of infective endocarditis in patients with HHT was conducted. 10 cases of IE linked to probiotics consumption and 6 cases of IE in patients with HHT were found.

Conclusions

Consumption of probiotics can pose a risk of serious infections in patients with particular predisposing factors. Patients with HHT can be considered at risk because of their predisposition to infections. Prophylaxis with antibiotics before nasal packings in patients with HHT can be considered.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-2956-5) contains supplementary material, which is available to authorized users.

The function of probiotics on the treatment of ventilator-associated pneumonia (VAP): facts and gaps

Probiotics have been used for centuries in making fermented dairy products. The health benefits related to probiotics consumption are well recognized and they are generally regarded as safe (GRAS). Their therapeutic effects are due to the production of a variety of antimicrobial compounds, such as short-chain fatty acids, organic acids (such as lactic, acetic, formic, propionic and butyric acids), ethanol, hydrogen peroxide and bacteriocins. Ventilator-associated pneumonia (VAP) is a nosocomial infection associated with high mortality in intensive care units. VAP can result from endotracheal intubation and mechanical ventilation. These interventions increase the risk of infection as patients lose the natural barrier between the oropharynx and the trachea, which in turn facilitates the entry of pathogens through the aspiration of oropharyngeal secretions containing bacteria into the lung. In order to prevent this, probiotics have been used extensively against VAP. This review is an update containing information extracted from recent studies on the use of probiotics to treat VAP. In addition, probiotic safety, the therapeutic properties of probiotics, the probiotic strains used and the action of the probiotics mechanism are reviewed. Furthermore, the therapeutic effects of probiotic treatment procedures for VAP are compared to those of antibiotics. Finally, the influences of bacteriocin on the growth of human pathogens, and the side-effects and limitations of using probiotics for the treatment of VAP are addressed.

Importance of Molecular Methods to Determine Whether a Probiotic is the Source of Lactobacillus Bacteremia

There has been an increasing interest in the use of probiotic products for the prevention of Clostridium difficile infection (CDI). Bio-K+(®) is a commercial probiotic product comprising three strains of lactobacilli--Lactobacillus acidophilus CL1285(®), Lact. casei LBC80R(®) and Lact. rhamnosus CLR2(®)--that have been applied to prevent CDI. Generally considered as safe, lactobacilli have potential to cause bacteremia, endocarditis and other infections. The source of Lactobacillus bacteremia can be normal human flora or lactobacilli-containing probiotic. The aim of this study was to assess whether probiotic lactobacilli caused bacteremia and to show the value of molecular identification and typing techniques to determine probiotic and patient strain relatedness. We report an episode of Lactobacillus bacteremia in a 69-year-old man admitted to a hospital with severe congestive heart failure. During his hospitalization, he required long-term antibiotic therapy. Additionally, the patient received Bio-K+(®) probiotic as part of a quality improvement project to prevent CDI. Subsequently, Lactobacillus bacteremia occurred. Two independent blinded laboratory evaluations, using pulse field gel electrophoresis, 16S rRNA gene sequencing and DNA fingerprint analysis (rep-PCR), were performed to determine whether the recovered Lact. acidophilus originated from the probiotic product. Ultimately, the patient strain was identified as Lact. casei and both laboratories found no genetic relation between the patient's strain and any of the probiotic lactobacilli. This clinical case of lactobacillus bacteremia in the setting of probiotic exposure demonstrates the value of using discriminatory molecular methods to clearly determine whether there were a link between the patient's isolate and the probiotic strains.

Lactobacillus bacteremia: Pathogen or prognostic marker?

OBJECTIVE

Lactobacillus bacteremia is a rare event and its epidemiology is poorly known. Whether Lactobacillus bacteremia is a contaminant, a risk factor, or a risk marker of death remains an open question.

PATIENTS AND METHODS

We conducted a retrospective study of patients presenting with Lactobacillus bacteremia (LB), between January 2005 and December 2014, at the Grenoble University Hospital.

RESULTS

LB was observed in 38 patients (0.34% of all positive blood cultures). Cancer (40%), immunosuppression (37%), and use of central venous devices (29%) were frequently associated with LB. We observed a significant increase with time in the number of Lactobacillus positive blood cultures among all blood cultures performed (P=0.04). LBs were divided into two clinical-biological presentations: secondary bacteremia with a known portal of entry (n=30) and isolated bacteremia (n=8). Case fatality was 31% at D28, 55.2% at 1 year in the secondary bacteremia group, and 12.5% (both at D28 and 1 year) in the isolated bacteremia group. Secondary bacteremia with a known portal of entry was significantly associated with case fatality after adjustment for age, co-infection, cancer, immunosuppression, diabetes, and sex (OR 14.9 [1.04-216] P=0.047) for fatality at one year, but not for D28 fatality (P=0.14).

CONCLUSION

Lactobacillus bacteremia may be an important marker of disease severity rather than a pathogen, suggesting comorbidities. It should not be considered a contaminant, but should lead physicians to screen for associated infections and underlying diseases.

Incidence and outcomes of bloodstream infections among hematopoietic cell transplant recipients from species commonly reported to be in over-the-counter probiotic formulations

BACKGROUND

Probiotic supplementation has been promoted for numerous health conditions; however, safety in immunosuppressed patients is unknown. We evaluated bloodstream infections (BSIs) caused by common probiotic organisms in hematopoietic cell transplant recipients.

METHODS

All blood culture (BC) results from a cohort of hematopoietic cell transplant recipients transplanted at Fred Hutchinson Cancer Research Center in Seattle, Washington, between 2002 and 2011 were reviewed. Patients with at least 1 positive BC for common probiotic organisms (Lactobacillus species, Bifidobacterium species, Streptococcus thermophilus, and Saccharomyces species) within 1 year post hematopoietic cell transplantation (HCT) were considered cases. Data were collected from center databases, which contain archived laboratory data, patient demographics, and clinical summaries.

RESULTS

A total of 19/3796 (0.5%) patients developed a BSI from one of these organisms within 1 year post HCT; no Bifidobacterium species or S. thermophilus were identified. Cases had a median age of 49 years (interquartile range [IQR]: 39-53), and the majority were allogeneic hematopoietic cell transplant recipients (14/19, 74%). Most positive BCs were Lactobacillus species (18/19) and occurred at a median of 84 days (IQR: 34-127) post transplant. The incidence rate of Lactobacillus bacteremia was 1.62 cases per 100,000 patient-days; the highest rate occurred within 100 days post transplant (3.3 per 100,000 patient-days). Eight patients (44%) were diagnosed with acute graft-versus-host disease of the gut prior to the development of bacteremia. No mortality was attributable to any of these infections.

CONCLUSION

Organisms frequently incorporated in available over-the-counter probiotics are infrequent causes of bacteremia after HCT. Studies evaluating the use of probiotics among high-risk patients are needed.

Prevalence of probiotic use among inpatients: A descriptive study of 145 U.S. hospitals

BACKGROUND

To inform clinical guidance, public health efforts, and research directions, probiotic use in U.S. health care needs to be better understood. This work aimed to assess the prevalence of inpatient probiotic use in a sample of U.S. hospitals.

METHODS

Probiotic use among patients discharged in 2012 was estimated using the MarketScan Hospital Drug Database. In addition, the annual trend in probiotic use (2006-2012) was assessed among a subset of hospitals.

RESULTS

Among 145 hospitals with 1,976,167 discharges in 2012, probiotics were used in 51,723 (2.6%) of hospitalizations occurring in 139 (96%) hospitals. Patients receiving probiotics were 9 times more likely to receive antimicrobials (P < .0001) and 21 times more likely to have a Clostridium difficile infection diagnosis (P < .0001). The most common probiotic formulations were Saccharomyces boulardii (32% of patients receiving probiotics), Lactobacillus acidophilus and Lactobacillus bulgaricus (30%), L acidophilus (28%), and Lactobacillus rhamnosus (11%). Probiotic use increased from 1.0% of 1,090,373 discharges in 2006 to 2.9% of 1,006,051 discharges in 2012 (P < .0001).

CONCLUSIONS

In this sample of U.S. hospitals, a sizable and growing number of inpatients received probiotics as part of their care despite inadequate evidence to support their use in this population. Additional research is needed to guide probiotic use in the hospital setting.

Lactobacillus species: taxonomic complexity and controversial susceptibilities

The genus Lactobacillus is a taxonomically complex and is composed of over 170 species that cannot be easily differentiated phenotypically and often require molecular identification. Although they are part of the normal human gastrointestinal and vaginal flora, they can also be occasional human pathogens. They are extensively used in a variety of commercial products including probiotics. Their antimicrobial susceptibilities are poorly defined in part because of their taxonomic complexity and are compounded by the different methods recommended by Clinical Laboratory Standards Institute and International Dairy Foundation. Their use as probiotics for prevention of Clostridium difficile infection is prevalent among consumers worldwide but raises the question of will the use of any concurrent antibiotic effect their ability to survive. Lactobacillus species are generally acid resistant and are able to survive ingestion. They are generally resistant to metronidazole, aminoglycosides and ciprofloxacin with L. acidophilus being susceptible to penicillin and vancomycin, whereas L. rhamnosus and L. casei are resistant to metronidazole and vancomycin.

Mechanisms and therapeutic effectiveness of lactobacilli

The gut microbiome is not a silent ecosystem but exerts several physiological and immunological functions. For many decades, lactobacilli have been used as an effective therapy for treatment of several pathological conditions displaying an overall positive safety profile. This review summarises the mechanisms and clinical evidence supporting therapeutic efficacy of lactobacilli. We searched Pubmed/Medline using the keyword ‘Lactobacillus’. Selected papers from 1950 to 2015 were chosen on the basis of their content. Relevant clinical and experimental articles using lactobacilli as therapeutic agents have been included. Applications of lactobacilli include kidney support for renal insufficiency, pancreas health, management of metabolic imbalance, and cancer treatment and prevention. In vitro and in vivo investigations have shown that prolonged lactobacilli administration induces qualitative and quantitative modifications in the human gastrointestinal microbial ecosystem with encouraging perspectives in counteracting pathology-associated physiological and immunological changes. Few studies have highlighted the risk of translocation with subsequent sepsis and bacteraemia following probiotic administration but there is still a lack of investigations on the dose effect of these compounds. Great care is thus required in the choice of the proper Lactobacillus species, their genetic stability and the translocation risk, mainly related to inflammatory disease-induced gut mucosa enhanced permeability. Finally, we need to determine the adequate amount of bacteria to be delivered in order to achieve the best clinical efficacy decreasing the risk of side effects.

Probiotics and synbiotics for the prevention of postoperative infections following abdominal surgery: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Postoperative infections, particularly surgical site infections (SSIs), cause significant morbidity and mortality. Probiotics or synbiotics are a potential prevention strategy.

AIM

To evaluate the efficacy of probiotics/synbiotics for reducing postoperative infection risk following abdominal surgery.

METHODS

We searched AMED, Central, CINAHL, Embase, Medline, and grey literature for randomized controlled trials of elective abdominal surgery patients administered probiotics or synbiotics compared to placebo or standard care. Primary outcome was SSIs. Secondary outcomes were adverse events, respiratory tract infections (RTIs), urinary tract infections (UTIs), combined infections, length of hospital stay, and mortality. Using random-effects meta-analyses, we estimated the relative risk (RR) or mean difference (MD) and 95% confidence interval (CI). Tests were performed for heterogeneity, subgroup and sensitivity analyses were conducted, and the overall evidence quality was graded.

FINDINGS

We identified 20 trials (N = 1374 participants) reporting postoperative infections. Probiotics/synbiotics reduced SSIs (RR: 0.63; 95% CI: 0.41-0.98; N = 15 studies), UTIs (RR: 0.29; 95% CI: 0.15-0.57; N = 11), and combined infections (RR: 0.49; 95% CI: 0.35-0.70; N = 18). There was no difference between groups for adverse events (RR: 0.89; 95% CI: 0.61-1.30; N = 6), RTIs (RR: 0.60; 95% CI: 0.36-1.00; N = 14), length of stay (MD: -1.19; 95% CI: -2.94 to 0.56; N = 12), or mortality (RR: 1.20; 95% CI: 0.58-2.48; N = 15).

CONCLUSION

Our review suggests that probiotics/synbiotics reduce SSIs and UTIs from abdominal surgeries compared to placebo or standard of care, without evidence of safety risk. Overall study quality was low, owing mostly to imprecision (few patients and events, or wide CIs); thus larger multi-centered trials are needed to further assess the certainty in this estimate.

The potential risks of probiotics among HIV-infected persons: Bacteraemia due to Lactobacillus acidophilus and review of the literature

Lactobacillus sp. are commensal organisms that are increasingly reported to cause invasive infections among immunosuppressed persons. However, few data exist regarding the occurrence and risk factors of these infections among HIV-infected persons. Further, the safety of products that contain lactobacilli (e.g. probiotics) in certain populations, including those with HIV/AIDS, is unclear. We report a case of Lactobacillus acidophilus bacteraemia in a patient with AIDS temporally related to excessive consumption of probiotic-enriched yogurt, and provide a comprehensive review of the literature of Lactobacillus sp. infections among HIV-infected persons.