Case 7 occurred in a 73-year-old female who was initially admitted due to pneumonia and acute kidney injury. The patient was treated empirically with vancomycin, levofloxacin, and piperacillin-tazobactam. On hospital day 3, the patient developed copious diarrhea, nausea, leukocytosis (WBC 20,000/μL) and serum creatinine increased 151% of the premorbid level. Clostridium difficile toxin was detected and oral metronidazole 500 mg three times daily was initiated. Tigecycline was added on hospital day 5 based on recommendations by the consulting infectious diseases specialist. Tigecycline was initiated instead of vancomycin due to the additional coverage of the patient’s concomitant vancomycin-resistant enterococcal urinary tract infection. The patient was successfully treated with 4 days of combination therapy with tigecycline and metronidazole with resolution of all CDI symptoms. No side effects attributed to tigecycline use were noted, and she had no documented CDI recurrence 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.