Bacterial infection is one of the most important etiologic factors of chronic acalculous cholecystitis. Sources of infection may be diseases of the nasopharynx and paranasal sinuses (chronic tonsillitis, sinusitis); oral cavity (stomatitis, gingivitis, periodontosis); urinary system (cystitis, pyelonephritis); reproductive system (prostatitis, urethritis); gynecological diseases (adnexitis, endometritis); infectious bowel diseases; viral liver damage.