Obstructive jaundice: Studies on predictors of biliary infection and microbiological analysis in an HIV setting

Early diagnosis of biliary infection is critical for timely antimicrobial therapy and biliary drainage. HIV infection may influence the spectrum and severity of biliary infection in an environment with a high HIV prevalence. Charcot's triad has low sensitivity and higher specificity for biliary infection, and more sensitive markers are required.

To investigate possible predictors of biliary infection (bacteriobilia) and identify the microbiological spectrum in patients presenting with biliary obstruction to a tertiary institute in an environment with a high prevalence of HIV.

Bile was assessed for infection at endoscopic retrograde cholangiopancreatography, percutaneous transhepatic cholangiography and surgery, and the roles of clinical/haematological factors, C-reactive protein (CRP) and procalcitonin (PCT) in determining biliary infection were evaluated.

One hundred and six patients with obstructive jaundice had a mean age of 52 years (range 21 - 58); most were female (74%), and 36 (34%) were infected with HIV, with a mean CD4 count of 495 cells/µL. Choledocholithiasis (53%), biliary strictures (21%) and head of pancreas tumour (8%) were the main aetiopathologies. Bile was obtained for microbial culture from 104 patients (98%), and 56 (54%) were infected. Gram-negative bacteria were most frequent (58%), and 2 HIV-infected patients had fungal infections (Candida albicans and Aspergillus fumigatus). Screening for endoscopy-associated infections revealed Pseudomonas aeruginosa. PCT was a poor predictor of bacterial infection, whereas CRP was a fair predictor.

The majority of bacteria cultured were sensitive to ciprofloxacin or amoxicillin-clavulanate. Duodenoscopes were a potential source of Pseudomonas infection.