C. diff strain strikes people in community
C. diff strain strikes people in community
Toxin production off the charts
Clostridium difficile continues to emerge in a more pathogenic form with a new epidemiological profile. Particularly disturbing are new reports in four states of infections in patients previously thought to be at low risk for C. diff.
Considered in the context of recent high-morbidity, hospital-associated outbreaks in North America, the United Kingdom, and the Netherlands, the cases of severe C. diff appear to reflect a "changing epidemiology," the Centers for Disease Control and Prevention reports.1 Clinical features that have been less common in the past include close-contact transmission, high recurrence rate, young patient age, bloody diarrhea, and lack of antimicrobial exposure.
C. difficile exotoxins A and B cause colonic dysfunction and cell death. A new emerging epidemic strain of the pathogen produces 16 times more toxin A and 23 times more toxin B compared with other common strains. Virulent strains can cause more severe disease in populations at high risk, but also cause more frequent, severe disease in populations previously at low risk (e.g., otherwise healthy persons with little or no exposure to health care settings or antimicrobial use).
In Pennsylvania and three other states, severe C. diff infections have occurred in two groups traditionally considered low risk: healthy people living in the community and peripartum women (those in the last month of gestation or the first few months after delivery). The findings underscore the importance of judicious antimicrobial use, the need for community clinicians to maintain a higher index of suspicion for C. diff, and the need for surveillance to better understand the changing epidemiology of the pathogen, the CDC concluded.
CDC case reports
• Case 1. A woman aged 31 years who was 14 weeks pregnant with twins went to a local emergency department (ED) after three weeks of intermittent diarrhea, followed by three days of cramping and watery, black stools four to five times daily. Stool specimens tested positive for C. difficile toxin, and the patient was admitted. Her only antimicrobial exposure during the preceding year was trimethoprim-sulfamethoxazole (for a urinary tract infection) approximately three months before admission. She was treated with metronidazole and discharged but was readmitted the next day for 18 days with severe colitis, receiving metronidazole, cholestyramine, and oral vancomycin. She improved on vancomycin and was allowed to return home. However, four days later she was readmitted with diarrhea and hypotension. She spontaneously aborted her fetuses. Despite aggressive treatment including a subtotal colectomy, intubation, and inotropic medication, the patient died on the third hospital day. Histopathologic examination of the colon demonstrated megacolon with evidence of pseudomembranous colitis.
• Case 2. A girl aged 10 years (unrelated and without contact with case 1) went to a children’s hospital ED because of intractable diarrhea, projectile vomiting, and abdominal pain. She had not taken antimicrobials during the preceding year. Stool specimens were positive for C. difficile toxin. The child had been healthy until two weeks before the ED visit, when she became symptomatic within days of her younger brother having a febrile diarrheal illness. The boy was not on antimicrobials when he became ill. His symptoms resolved within two to three days without medical treatment, but his sister had fever as high as 102° F (39°C), abdominal pain, and diarrhea. One week into her illness, she was examined by a clinician, who performed a rapid streptococcal antigen test on a swab from her oropharynx; the result was positive.
The patient was prescribed amoxicillin but was unable to take it because of her stomach cramps and diarrhea; her symptoms worsened until she was having liquid stools up to 14 times daily. Symptoms resolved with hospital admission and the administration of intravenous fluids, electrolytes, and metronidazole.
Reference
- Centers for Disease Control and Prevention. Severe Clostridium difficile-Associated Disease in Populations Previously at Low Risk — Four States, 2005. MMWR 2005 54(47);1201-1205