In this case study,A 72-year-old woman was admitted to Ordos Central Hospital (Ordos, Inner Mongolia, China) complaining of a 2-day history of fever, with a temperature up to 39.8˚C, accompanied with chills, abdominal pain and nausea. She denied hypertension, diabetes and hepatitis. Her earlier medical history was not significant, pertinent medical history included cholelithiasis treated with cholecystectomy in 2010.
Few positive findings were noted on the physical examination except the patient was visibly icteric. The patient weighed 69kg, was febrile with a temperature of 39.8°C , with a heart rate of 84 beats/minute, a respiratory rate of 20 breaths/minute, a blood pressure of 133/79 mmHg, and an oxygen saturation of 98% on room air. Abdominal examination revealed a soft abdomen, no palpable lymph nodes were found and Murphy’s sign was negative.
At admission, the laboratory investigation revealed abnormal liver function tests consistent with cholestatic jaundice (alanine aminotransferase [ALT] 312 U/L aspartate aminotransferase [AST] 332 U/L, alkaline phosphatase [ALP] 153 U/L, total bilirubin [TBIL] 85.7 umol/L, direct bilirubin [DBIL] 59 umol/L and albumin 42.7 g/L). The neutrophil (NEU) count (7930/mm3 [normal range 1800-6300/mm3]) were elevated, C-reactive protein (CRP) (180.56 mg/L [normal range 5–10 mg/L]) and Procalcitonin (PCT) (13.86 ng/mL [normal range < 0.1ng/mL])were increased.
The chest X-ray was negative. Abdominal sonography was arranged, revealing thickened common duct wall and cholangitis. A magnetic resonance cholangiopancreatography (MRCP) revealed postcholecystectomy, choledochectasia, choledocholith and a dilated intrahepatic bile duct.
After her admission into hospital, blood culture was performed and empirical treatment with intravenous infusion of piperacillin-tazobactam (4.5 g every 6 h) was started. The blood culture sample was flagged as positive after 24 hours of incubation in an automated BacT/ALERT 3D blood culture system (BioMérieux, France) and revealed the presence of non-fermenting gram-negative bacilli (NFGNB) with dry edges on blood agar and MacConkey agar (Fig 1). After 2 days empiric treatment, the patient still had a fever. Therefore, a second blood sample was cultured and still revealing NFGNB. Subsequently, the identification of the isolate was based on the protein profile using MALDI-TOF MS (BioMérieux, France), and the isolate was identified as P. oleovorans with a high confidence of 99.9% (Fig 2). Antimicrobial susceptibility testing (AST) was done by microdilution method using a commercially available kit, Vitek 2 Compact (BioMérieux, France). The results of AST showed that P. oleovorans to be sensitive to ciprofloxacin, levofloxacin, ceftazidime, piperacillin-tazobactam, amoxicillin-clavulanate, imipenem, amikacin, tobramycin, doxycycline and sulfamethoxazole-trimethoprim (Table 1). The patient was started on piperacillin- tazobactam, according to the susceptibility pattern, the regimen continued. Blood culture performed after 7 days of therapy was negative. The patient made an uncomplicated recovery and was subsequently discharged on piperacillin-tazobactam therapy 3 weeks after admission.