Letter to the Editor: Acinetobacter junii Cholangitis with a Metallic Biliary Stent for Palliation of Klatskin Tumor

To the Editor:

Acinetobacter junii belongs to a genus (Acinetobacter) of gram-negative coccobacilli that can colonize human skin [1,2]. Although Acinetobacter junii infections are rarely reported [2], they are associated with previous antimicrobial treatment, invasive procedures, and malignancy [3]. This report describes an adult male patient with advanced cholangiocarcinoma treated with a metallic biliary stent to palliate malignant jaundice. He developed acute cholangitis with Acinetobacter junii bacteremia.

A 69-year-old male with a smoking history of 50 pack-years presented with tea-colored urine, bloated abdomen, and yellow discoloration of his skin and eyes for three days. He had a past medical history of hypertension and gastroesophageal reflux disease. His vital parameters were stable, and abdominal examination was unremarkable. A magnetic resonance imaging (MRI) scan of the abdomen revealed Bismuth type 3B Klatskin tumor with involvement of the common hepatic artery. A staging computed tomography (CT) scan confirmed MRI findings and the absence of metastases. Endoscopic biliary decompression was attempted but because of technical difficulty. Two percutaneous transhepatic biliary drainage (PTBD) tubes were inserted to relieve jaundice in segment II and segment VI biliary ducts, respectively. A multidisciplinary tumor board deemed the lesion unresectable and recommended palliative chemotherapy. One metallic biliary stent was placed in each of the right and left hepatic ducts.

An episode of sepsis complicated the patient's hospital stay and his blood cultures grew pan-sensitive Acinetobacter junii. Intravenous amoxicillin-clavulanic acid and gentamicin were prescribed. Upon clinical improvement over the next few days, antibiotics were changed to oral ciprofloxacin, and the patient was discharged.

The Acinetobacter genus has low pathogenic potential, with typical cases reported as opportunistic nosocomial infections in immunocompromised hosts [1]. Acinetobacter baumannii is the main pathogenic species [1]. Although Acinetobacter junii infections are rarer, there are reports of urinary and systemic sepsis [2,4]. Our patient had advanced inoperable Klatskin tumor. In addition, because of deep malignant jaundice, he could be considered immunocompromised, thus predisposed to Acinetobacter junii sepsis.

In patients with acute pyogenic cholangitis, gram-negative bacteremia caused by cholangiovenous reflux from elevated intra-biliary pressures can result in multiorgan dysfunction. Thus, urgent biliary decompression and intravenous broad-spectrum antibiotic agents are integral to good clinical outcomes [5]. Local hospital antibiogram and antibiotic stewardship initiatives are essential components of the sepsis care bundle. Although Acinetobacter baumannii is resistant to commonly used antibiotic agents, Acinetobacter junii is usually susceptible to most [1]. In our patient, Acinetobacter junii was susceptible to ceftriaxone, ceftazidime, cefepime, ampicillin/sulbactam, piperallicin/tazobactam, meropenem, gentamicin, amikacin, ciprofloxacin, and cotrimoxazole. Acinetobacter junii possibly gained access during the percutaneous biliary drainage procedure, however, this cannot be established. Our unit has a policy of prophylactic antibiotic therapy for percutaneous biliary interventions.

In conclusion, Acinetobacter junii bacteremia can result from a breach in the skin during invasive interventions in immunocompromised patients with advanced malignancy. Because Acinetobacter junii is susceptible to the most commonly available antibiotics, treatment should result in good clinical outcomes if a timely diagnosis is made. This is the first report of Acinetobacter junii acute cholangitis on a background of the metallic biliary endoprosthesis to palliate malignant jaundice from Klatskin tumor.