Repeat stool testing for Clostridium difficile using enzyme immunoassay in patients with inflammatory bowel disease increases diagnostic yield

Acute severe ulcerative colitis: management advice for internal medicine and emergency physicians

Acute severe ulcerative colitis is a medical emergency that warrants in-patient management. This is best served within a multidisciplinary team setting in specialised centres or with expert consultation. Intravenous corticosteroids remain the cornerstone in the management of ASUC and should be initiated promptly, along with general management measures and close monitoring of patients. Unfortunately, one-third of patients will fail to respond to steroids. Response to intravenous corticosteroid therapy needs to be assessed on the third day and rescue therapies, including cyclosporine and infliximab, should be offered to patients not responding. Choice of rescue therapy depends on experience, drug availability and factors associated with each individual patient, such as comorbidities, previous medications or contra-indications to therapy. Patients who have not responded within 7 days to rescue therapy must be considered for surgery. Surgery is a treatment option in ASUC and should not be delayed in cases of failure of medical therapy, because such delays increase surgical morbidity and mortality. This review summarises the current management of acute severe ulcerative colitis and discusses potential future developments.

An approach to acute severe ulcerative colitis

Introduction: Despite the introduction of novel therapies and treatment strategies for ulcerative colitis (UC), many patients develop acute, severe episodes, warranting prompt care and aggressive management. There is a significant unmet need to improve outcomes in these patients. Clinicians must be able to identify those that will have worse prognosis and plan an aggressive therapy with an early/proactive adjustments in management if needed.Areas covered: The aim of this review is to evaluate the most recent evidence on the assessment and management of patients with acute severe ulcerative colitis. We searched the mainstream literature search engines for the most recent evidence on diagnosis and management of acute UC.Expert Opinion: The approach to patients with severe UC includes clinical and endoscopic assessment of disease severity and ruling out over-infections. While intravenous corticosteroids remain the first line therapy for acute severe colitis, many patients do not respond and require escalation to calcineurin inhibitors or infliximab, and may ultimately require colectomy. Even though several novel therapies are available or in development, their role in acute severe episodes of colitis is unknown.

A Laboratory Medicine Best Practices Systematic Review and Meta-analysis of Nucleic Acid Amplification Tests (NAATs) and Algorithms Including NAATs for the Diagnosis of Clostridioides (Clostridium) difficile in Adults

The evidence base for the optimal laboratory diagnosis of Clostridioides (Clostridium) difficile in adults is currently unresolved due to the uncertain performance characteristics and various combinations of tests. This systematic review evaluates the diagnostic accuracy of laboratory testing algorithms that include nucleic acid amplification tests (NAATs) to detect the presence of C. difficile The systematic review and meta-analysis included eligible studies (those that had PICO [population, intervention, comparison, outcome] elements) that assessed the diagnostic accuracy of NAAT alone or following glutamate dehydrogenase (GDH) enzyme immunoassays (EIAs) or GDH EIAs plus C. difficile toxin EIAs (toxin). The diagnostic yield of NAAT for repeat testing after an initial negative result was also assessed. Two hundred thirty-eight studies met inclusion criteria. Seventy-two of these studies had sufficient data for meta-analysis. The strength of evidence ranged from high to insufficient. The uses of NAAT only, GDH-positive EIA followed by NAAT, and GDH-positive/toxin-negative EIA followed by NAAT are all recommended as American Society for Microbiology (ASM) best practices for the detection of the C. difficile toxin gene or organism. Meta-analysis of published evidence supports the use of testing algorithms that use NAAT alone or in combination with GDH or GDH plus toxin EIA to detect the presence of C. difficile in adults. There is insufficient evidence to recommend against repeat testing of the sample using NAAT after an initial negative result due to a lack of evidence of harm (i.e., financial, length of stay, or delay of treatment) as specified by the Laboratory Medicine Best Practices (LMBP) systematic review method in making such an assessment. Findings from this systematic review provide clarity to diagnostic testing strategies and highlight gaps, such as low numbers of GDH/toxin/PCR studies, in existing evidence on diagnostic performance, which can be used to guide future clinical research studies.

Clostridium difficile infection in inflammatory bowel disease: challenges in diagnosis and treatment

The problem of Clostridium difficile infection (CDI) has reached epidemic proportions, particularly in industrialized nations. The pathophysiology, disease course and the potential complications are well appreciated in the general hospitalized patient. However, when CDI occurs in the setting of inflammatory bowel disease (IBD), a number of distinct differences in the diagnosis and clinical management of the infection in this population should be appreciated by gastroenterologists, hospitalists and other care providers. This review highlights the unique aspects of CDI when it occurs in IBD patients with an emphasis on the challenge of distinguishing persistent infection from exacerbation of underlying chronic colitis. An understanding of how CDI may differ in presentation and how management should be altered can prevent serious and life-threatening complications.

Managing Clostridium difficile in inflammatory bowel disease (IBD)

Clostridium difficile (C. difficile) infection has emerged as a significant clinical challenge for patients suffering from inflammatory bowel disease (IBD). C. difficile can both precipitate and worsen flares of IBD, contributing to emergent colectomies and mortality. Advances in the management of C. difficile infection in IBD include recommendations for testing for this infection in the setting of clinical flare and hospitalization, improved diagnostic testing, identification of high rates of carriage and infection in pediatric IBD, and new data associating patterns of IBD genetic risk alleles with the development of this infection. Therapeutically, oral vancomycin has emerged as a superior treatment for IBD patients with moderate to severe disease compared with metronidazole. Although highly effective in the general population, fecal microbiome transplantation for recurrent C. difficile infection in IBD patients has been associated with colitis flare in the majority of patients who have received this treatment.

[Diagnostic options. Indications and validity]

BACKGROUND

A variety of diagnostic methods provide the necessary rational basis for diagnosis, assessment of disease activity and exclusion of possible complications for patients with inflammatory bowel disease (IBD).

AIM

Currently, a wide range of diagnostic methods is available and easily accessible. The clinical use of all these different methods is inherently possible. As there is no reference test for either diagnosis or monitoring of IBD, diagnostic techniques must be selected, applied and interpreted in an appropriate clinical context. The objective is to evaluate the clinical, laboratory and imaging techniques including ultrasound and endoscopy in different clinical situations.

RESULTS

In addition to clinical parameters, fecal calprotectin and abdominal ultrasound are helpful tools to assess the inflammatory activity. In patients with high inflammatory activity, a routine endoscopy is not beneficial. At best, endoscopy can be performed to document the extent of mucosal inflammation before initiating an intensified immunosuppressive therapy. Knowledge and experience in the management and treatment of IBD complications are critical in providing a rational use of specific diagnostic methods.

CONCLUSION

As a basic principle, the critical evaluation of diagnostic methods in patients with IBD is of great importance. Specific clinical situations require specific diagnostic techniques. Every diagnostic method performed should have a purpose.

Control of Clostridium difficile infection in the hospital setting

Clostridium difficile infection (CDI) has emerged as a leading challenge in the control of healthcare-associated infection (HCAI). The epidemiology of CDI has changed dramatically, this is associated with emergence of 'hypervirulent' strains, particularly PCR ribotype 027. Despite the epidemic spread of these strains, there are recent reports of decreasing incidence from healthcare facilities where multi-facetted targeted control programs have been implemented. We consider these changes in epidemiology and reflect on the tools available to control CDI in the hospital setting. The precise repertoire of measures adopted and emphasis on different interventions will vary, not only between healthcare systems, but also within different institutions within the same healthcare system. Finally, we consider both the sustainability of reductions already achieved, and the potential to reduce CDI further. This takes account of newly emerging data on more recent changes in the epidemiology of CDI, and the potential of novel interventions to decrease the burden of disease.

Diagnosis of Clostridium difficile infection: an ongoing conundrum for clinicians and for clinical laboratories

Clostridium difficile is a formidable nosocomial and community-acquired pathogen, causing clinical presentations ranging from asymptomatic colonization to self-limiting diarrhea to toxic megacolon and fulminant colitis. Since the early 2000s, the incidence of C. difficile disease has increased dramatically, and this is thought to be due to the emergence of new strain types. For many years, the mainstay of C. difficile disease diagnosis was enzyme immunoassays for detection of the C. difficile toxin(s), although it is now generally accepted that these assays lack sensitivity. A number of molecular assays are commercially available for the detection of C. difficile. This review covers the history and biology of C. difficile and provides an in-depth discussion of the laboratory methods used for the diagnosis of C. difficile infection (CDI). In addition, strain typing methods for C. difficile and the evolving epidemiology of colonization and infection with this organism are discussed. Finally, considerations for diagnosing C. difficile disease in special patient populations, such as children, oncology patients, transplant patients, and patients with inflammatory bowel disease, are described. As detection of C. difficile in clinical specimens does not always equate with disease, the diagnosis of C. difficile infection continues to be a challenge for both laboratories and clinicians.

Diagnosis and management of Clostridium difficile infection

Clostridium difficile infection (CDI) is increasing in frequency and severity in and out of the hospital, with a high probability of recurrence after treatment. The recent literature on CDI was reviewed using PubMed to include recent publications dealing with diagnosis and therapy. Real-time polymerase chain reaction is a sensitive and useful diagnostic test for CDI but there are growing concerns of false-positive test results if the rate of CDI is low in the patient population providing samples and/or if the population being studied commonly includes people with C difficile colonization. Recommended therapy of CDI includes oral metronidazole for milder cases of CDI and oral vancomycin or fidaxomicin for more severe cases, each given for 10 days. Colectomy is being performed more frequently in patients with fulminant CDI. For treatment of first recurrences the drug used in the first bout can be used again and for second recurrences longer courses of vancomycin often are given in a tapered dose or intermittently to allow gut flora reconstitution, or other treatments including fidaxomicin may be used. Bacteriotherapy with fecal transplantation is playing an increasing role in therapy of recurrent cases. Metagenomic studies of patients with CDI during successful therapy are needed to determine how best to protect the flora from assaults from antibacterial drugs and to develop optimal therapeutic approaches. Immunotherapy and immunoprophylaxis offer opportunities to prevent CDI, to speed up recovery from CDI, and to eliminate recurrent infection. Humanized monoclonal antitoxin antibodies and active immunization with vaccines against C difficile or its toxins are both in development and appear to be of potential value.