Case 1 occurred in a 64-year-old female who was admitted for community onset CDI. This patient had multiple risk factors for CDI, including recent antibiotic use (meropenem and vancomycin for pneumonia, and levofloxacin for chronic leukopenia) and immunosuppression. She was initially leukopenic secondary to end-stage liver disease awaiting transplantation with mild CDI (WBC 600/μL, serum creatinine 138% relative to baseline). She was treated with intravenous metronidazole 500 mg three times daily for CDI starting on hospital day 1. On hospital day 2, follow-up PCR for toxigenic C. difficile remained positive. Her early hospital course was unremarkable; however, she developed ileus, nausea, and vomiting on hospital day 4 and her CDI had progressed from mild to a severe complicated case. The patient was transferred to the intensive care unit (ICU) and oral vancomycin 125 mg four times daily was added to the regimen. On hospital day 6, the patient’s ileus remained unresolved, her serum creatinine level increased to 188% of the premorbid level and she developed severe abdominal pain. Due to the concerns for limited effectiveness of oral vancomycin in the setting of ileus, intravenous tigecycline was added to the regimen on hospital day 6 as a 100-mg loading dose followed by 50-mg doses twice daily. This patient was treated with a combination of intravenous tigecycline, oral vancomycin, and intravenous metronidazole for 10 days. No side effects of tigecycline therapy were noted in the electronic medical record. Follow-up PCR for toxigenic C. difficile was negative at the end of treatment. This patient was at high risk of recurrence due to her chronic antibiotic use and pancytopenia. Therefore, she was discharged to a long-term care facility where she completed a 30-day vancomycin taper. She had no subsequent recurrence of CDI on record.
Case 2 occurred in a 46-year-old male who was admitted to the ICU with severe diarrhea and septic shock requiring 13 L fluid resuscitation and vasopressors. The patient presented with severe leukocytosis (WBC 35,400/μL) and renal impairment (serum creatinine increased 166% of the premorbid level). This patient had a number of risk factors for CDI, including admission from a long-term care facility and multiple prior antibiotic use (see Table for full listing). He was treated initially with oral metronidazole 500 mg three times daily. Oral metronidazole was switched to intravenous and oral vancomycin 125 mg four times daily was added on hospital day 2 upon detection of toxigenic C. difficile. At this point, the patient was intubated due to decreasing respiratory function and pulmonary edema. He also had other symptoms of severe complicated CDI, included nausea and vomiting, abdominal pain, colonic wall thickening, and ascites. Oral vancomycin was changed to rectal vancomycin 500 mg four times daily on hospital day 3 due to the development of paralytic ileus. This regimen continued through hospital day 7, with fever, ileus, and abdominal pain resolving. On hospital day 8, the patient again developed diarrhea with abdominal pain and persisting leukocytosis (WBC 24,300/μL). Due to these non-resolving symptoms and the severity of the patient’s condition, intravenous tigecycline was added on hospital day 8 as a 100-mg loading dose followed by 50 mg twice daily. Clinical cure was achieved after 8 days of treatment with tigecycline, rectal vancomycin, and intravenous metronidazole. Due to the high risk of recurrence, the patient completed a vancomycin taper upon discharge to a long-term care facility. There was no documented recurrence of CDI on record.