US physicians vary widely in how they diagnose and manage Clostridioides difficile infection (CDI), differing in guideline use, testing strategies, and treatment choices, according to results of a national survey of gastroenterologists (GIs), infectious diseases specialists (IDs), and primary care physicians (PCPs).

Investigators found substantial cross-specialty variation in adherence to guideline-recommended testing algorithms, antibiotic prescribing patterns, and familiarity with newer microbiome-based therapies, highlighting persistent gaps in CDI management across specialties and practice settings and the need for more standardization and education as the CDI treatment landscape continues to evolve.

“Clinicians should be familiar with current practice guidelines and should use guideline-recommended diagnostic algorithms for diagnosing CDI,” lead author Abhishek Deshpande, MD, PhD, associate professor, Alice L. Walton School of Medicine, Bentonville, Arkansas, told Medscape Medical News.

Moreover, “metronidazole should not be the default first-line agent, vancomycin and fidaxomicin have superior evidence profiles, and donor-derived microbiome therapeutics have a role in recurrence prevention,” said Deshpande. “The knowledge gap we identified across specialties warrants more education about these options.”

Multiple Specialties, Multiple Settings

“CDI remains among the most common healthcare-associated infections in the United States,” Deshpande said. “Multiple societies have published clinical practice guidelines with specific recommendations for its diagnosis and management.” Moreover, patients are currently “seen across multiple specialties and settings.”

The American College of Gastroenterology (ACG) and the Infectious Diseases Society of America/the Society for Healthcare Epidemiology of America (IDSA/SHEA) have released guidelines for CDI management. However, “conflicting recommendations in these guidelines may lead to inconsistencies in how physicians across specialties and settings approach the diagnosis and management of CDI,” the authors wrote.

Deshpande noted that the recent FDA approval of donor-derived microbiome therapeutics has “further expanded the treatment landscape,” but it’s “unclear how these newly approved treatments fit into current clinical practice.”

As advances in CDI diagnostics and treatment continue to unfold, Deshpande and colleagues “sought to determine whether diagnostic practices, treatment selection, and guideline adherence differed by physician specialty, to identify knowledge gaps, and to provide an evidence base to support more standardized care.”

They surveyed 302 US physicians who regularly care for patients with CDI (n = 101 GIs; n = 101 IDs; n = 100 PCPs). GI and ID respondents saw a minimum of three or four patients while PCPs saw one or two patients with CDI per month. Respondents were “evenly distributed” across age groups, but practice settings varied significantly among specialties, with IDs predominantly working in academic settings, and GIs and PCPs more likely to practice in individual/group settings.

Clinical Challenges and Ambiguities

When evaluating patients with suspected CDI, respondents across all specialties prioritized recent antibiotic use, prior history of CDI, and recent hospitalization as key risk factors. But there was no uniformity between specialties regarding which factors they considered when assessing risk. For example, GIs were more likely to consider a history of ulcerative colitis (89%) or Crohn’s disease (88%) than other specialists, whereas IDs and PCPs focused on prior CDI history (98% and 85%, respectively) and recent antibiotic exposure (94% and 93%, respectively).

When asked about diagnostic challenges, more GIs and IDs than PCPs identified asymptomatic C difficile colonization as the primary barrier (71% and 79% vs 45%, respectively), while GIs less frequently cited the challenge of distinguishing CDI from other causes of diarrhea than IDs and PCPs (47% and 64% vs 63%, respectively). On the other hand, physicians across all specialties “consistently” identified diarrhea and abdominal pain/cramping as the primary symptoms prompting consideration of a CDI diagnosis.

Adherence to guidelines varied greatly by specialty, with 50% of GIs following ACG guidelines, and almost all IDs (98%) following IDSA/SHEA guidelines. More PCPs than GIs and IDs reported that their institutions didn’t have set guidelines.

Regarding CDI diagnostic testing, more GIs and IDs used the recommended multistep algorithm than PCPs, who were more likely to use a single diagnostic test (51% and 74% vs 49%, respectively).

While GIs and IDs more frequently prescribed vancomycin taper and fidaxomicin, PCPs were more likely to prescribe metronidazole. Importantly, less than 10% of respondents felt “very knowledgeable” about donor-derived microbiome therapies, although 60% of GIs, 53% of IDs, and 50% of PCPs agreed that donor-derived microbiome therapies are “essential” for CDI management. More than half stated that real-world evidence of their safety and efficacy is needed.

The authors described several “clinically ambiguous” CDI scenarios — for example, diagnostic steps to take in the setting of asymptomatic C difficile colonization and managing patients whose CDI testing results are “discordant” (nucleic acid amplification test positive and toxin negative). “Our study findings highlight a need for simplified, standardized diagnostic algorithms that are implementable across practice settings,” they stated.

Familiarity with newer FDA-approved donor-derived microbiome therapeutics was “low” across all specialties, which represents a significant barrier to implementing these newer treatment options and reveals a pressing need for targeted education, particularly among PCPs,” the authors commented.

Limitations include the survey’s small sample size, as well as high response rates from physicians in certain states (eg, California and New York) and no responses from others (eg, Wyoming and Arkansas), which may reduce the generalizability of the findings. Moreover, the survey was conducted ~2 years prior to publication. Amid the rapidly changing CDI management landscape, provider attitudes and practices may have shifted since the time of data collection.

Nevertheless, the survey “revealed important opportunities for education and coordination around the use of guidelines for testing and treatment,” they said.

‘We Still Have a Ways to Go’

Commenting for Medscape Medical News, Bruce Hirsch, MD, of the Division of Infectious Diseases at Northwell Health’s North Shore University, Manhasset, New York, observed that the “current standard of therapy [of C difficile] has really changed quite a bit over the last decade, and certainly over the last two decades.”

Hirsch, a member of the Peggy Lillis Foundation Scientific Advisory Board, noted that PCP respondents more frequently used metronidazole, which is a “somewhat outmoded therapy” that was the “drug of choice in earlier eras but has now been recognized as much less active and less effective than some of the other treatments.” The survey also described some “ignorance about donor-derived microbiome therapies.” A fair number of respondence were “not taking advantage of some of the best therapies, particularly for recurrent C diff.”

The findings therefore suggest that although “we do have advances in C diff, we have a ways to go in terms of disseminating guidelines and making physicians aware of the current standard of therapy.”

This work was supported by independent medical education grants from Ferring Pharmaceuticals and the Alliance of Seres Therapeutics and Nestle Health Science. Deshpande disclosed research support from Clorox. The other authors’ disclosures are listed on the original paper. Hirsh disclosed no relevant financial relationships.

Batya Swift Yasgur, MA, LSW, is a freelance writer with a counseling practice in Teaneck, New Jersey. She is a regular contributor to numerous medical publications, including Medscape and WebMD, and is the author of several consumer-oriented health books.