A 74-year-old woman is brought to the emergency department from a skilled nursing facility due to a positive stool PCR test for Clostridioides difficile. The patient was discharged from the hospital to the nursing facility 10 days ago after treatment for urinary tract infection and septic shock. She developed C difficile-associated diarrhea during the hospitalization and completed a course of oral fidaxomicin therapy 3 days ago. This treatment resolved the diarrhea, nausea, and abdominal pain; yesterday, the patient had an episode of bloating, nausea, and loose stool after a meal at the nursing facility, prompting repeat stool testing. Since then, she has had no additional abdominal pain, nausea, vomiting, or diarrhea. Other medical conditions include hypertension, hyperlipidemia, ischemic stroke with residual left hemiparesis, and gastroesophageal reflux. Temperature is 37 C (98.6 F) , blood pressure is 130/68 mm Hg, and pulse is 84/min. The abdomen is soft, nondistended, and nontender, with normoactive bowel sounds in all quadrants. Rectal examination shows soft, brown stool negative for occult blood. Leukocyte count is 7,100/mm³.
The patient has no diarrhea or other gastrointestinal symptoms while in the emergency department. Prior to discharge, she asks if there is any way to prevent Clostridioides difficile-associated diarrhea in the future. In addition to minimizing antibiotic use, which of the following is most likely to prevent recurrent episodes of the disease in this patient?

Question

Quizplus · Accepted Answer

Explanation: Clostridioides difficile is a common commensal species in normal gut flora, although growth is typically suppressed by more populous anaerobes. Most people are asymptomatic carriers; however, C difficile-associated diarrhea (CDAD) can occur in patients with alterations in the gut microbiome, which allows for C difficile proliferation, or in those inoculated with a new, toxigenic isolate. The risk for developing CDAD is increased in those with the following: Antibiotic use: Antibiotics disrupt the barrier function of normal colonic flora. Fluoroquinolones, clindamycin, and broad-spectrum penicillins/cephalosporins are most likely to cause CDAD. Gastric acid suppression: C difficile spores are acid resistant, but proton pump inhibitors and H₂ blockers are thought to alter the colonic microbiome, which increases the risk for C difficile proliferation. Hospitalization: Nosocomial exposure accounts for most C difficile transmissions. Advanced age (>65): Older individuals often have diminished colonic immunity and greater exposure to antibiotics, proton pump inhibitors, and hospital environments. Minimizing antibiotic use is the most important way of reducing the risk for recurrent CDAD in this patient, but avoiding gastric acid suppression is also an important risk-reduction strategy. (Choice B) Chlorhexidine bathing can help prevent recurrences of methicillin-resistant Staphylococcus aureus, but it has not been conclusively shown to reduce the risk for CDAD. (Choice C) Physical inactivity is not a prominent risk factor for the development of CDAD. (Choice D) Probiotic-rich yogurt contains live microorganisms that, in theory, may repopulate the gut microbiome and reduce the proliferation of pathogenic bacteria. However, recent guidelines have not supported the use of probiotics for either primary or secondary prevention of C difficile infection because of insufficient evidence. (Choice E) Asymptomatic C difficile carriage rates are lower among health care workers (~0%-10%) than among adults who are hospitalized or residing in long-term care facilities (~20%-50%). The screening of asymptomatic carriers has not been shown to affect nosocomial transmission rates; hand hygiene and infection-control measures (eg, sporicidal disinfectants, contact isolation) are the most important means for preventing C difficile transmission. Educational objective: Minimizing the use of antibiotics and reducing gastric acid suppression can reduce the risk for recurrent Clostridioides difficile-associated diarrhea. References: Recurrent Clostridium difficile infection: risk factors, treatment, and prevention. (http://www.ncbi.nlm.nih.gov/pubmed/30400734) Association of gastric acid suppression with recurrent Clostridium difficile infection: a systematic review and meta-analysis. (http://www.ncbi.nlm.nih.gov/pubmed/28346595)

A 74-Year-Old Woman Is Brought to the Emergency Department from a Skilled