Are Certain Clinical Characteristics Associated with Severe C Diff Infections?

The US Centers for Disease Control and Prevention has classified Clostridium difficile (C diff) infections as an urgent threat to public health, yet it can be difficult for clinicians to classify the severity of infection. Similarly, lack of data leaves gaps in knowledge about if a correlation exists between severity, C diff treatment, and clinical outcomes.

In order to determine characteristics that can be used to classify C diff disease severity, a team of investigators from the University of Mississippi and University of Cincinnati collaborated on a study. The findings of their research, which set out to determine differences in the clinical characteristics between complicated and uncomplicated C diff infections were presented in a poster session at the Making a Difference in Infectious Diseases 2019 (MAD-ID) annual meeting.

In an exclusive interview at the meeting, Contagion® spoke with the poster presenter, Jaime Wagner, PharmD, a clinical assistant professor in the Department of Pharmacy Practice at the University of Mississippi, about the research (see video).

The study enrolled a total of 199 patients that were admitted for C diff infection between 2012 and 2017. Patients who were diagnosed by toxin B polymerase chain reaction and received C diff infection-active antimicrobials for ≥72 hours were included. However, the investigators excluded patients who were transferred on treatment for C diff infection and/or patients who were pregnant.

Of the total 199 enrolled patients, 143 (43%) were categorized as having an uncomplicated C diff infection while 56 patients (28%) were documented as having a complicated infection. Complicated infections were defined as the occurrence of death within 30 days following diagnosis and/or observation of any abnormal abdominal images.

The median age of the patient population was 55 years [range 42-66 years] and 47% of the population was male. Fifty-six percent of the participants were African America, 40% were Caucasian and 4% were reported as other or unknown. Additionally, 31% of participants were noted to have chronic kidney disease and 10% had inflammatory bowel disease, with a median Charlson Score of 4 [2-8].

The investigators observed that patients with complicated infections had a higher median APACHE II (22 vs 13; p=0.023). Further, those patients had longer durations of carbapenem exposure (6 vs 3 days; p=0.023), more frequent exposure to fluoroquinolones (46% vs 29%; p=0.017), and higher rates of exposure to trimethoprim and sulfamethoxazole (14% vs 4%; p=0.026).

Analyses also indicate that patients with complicated infections were more likely to have been previously hospitalized (77% vs 59%; p=0.017) and investigators observed numerically less time between the previous hospitalization and recent C diff episode (28 days vs 48 days; p=0.132). This patient population was also more likely to receive concomitant non-C diff infection antibiotics (77% vs 62%; p=0.022) for 2 days prior to diagnosis and to have been discharged with oral vancomycin (91% vs 49%; p=0.016).

On the other hand, the investigators observed that, patients with uncomplicated infections were more likely to have a lower C-Reactive Protein (8 vs 19; p=0.023), lower anion gap (15 vs 17; p=0.040), higher albumin (2.9 vs 2.7; p=0.020), and lower lactate (1.3 vs 2; p=0.029). The uncomplicated patients were also found to be more likely to have a shorter length of stay (7 days vs 11 days; p=0.019) and be discharged home (75% vs 50%; p=0.001).

Wagner also shared her biggest takeaways from the research in her interview with Contagion® (see video).

According to the investigators, “several clinical characteristics were more closely associated with complicated vs. uncomplicated C diff infection.” Yet the authors note that more research is needed to evaluate these variables as predictions of C diff disease severity.

The poster “Determining the Optimal Characteristics to Classify Clostridioides difficile Disease Severity,” was presented on Thursday, May 9, 2019 at MAD-ID 2019 in Orlando, Florida.