fistulan

Fistulan is a term used in some medical literature to denote a fistula, an abnormal tract that connects two epithelial surfaces, such as skin to mucosa or between two organs. The more common English term is fistula; fistulan appears in certain languages or older texts and is often context-specific. Fistulas may be classified by location or source, including anorectal fistulas (connecting the anal canal to perianal skin), enterocutaneous fistulas (between the intestinal tract and skin), vesicovaginal fistulas (between bladder and vagina), tracheoesophageal fistulas, and fistulas of vascular origin such as arteriovenous fistulas created for hemodialysis. Fistulas can be congenital or acquired and may result from chronic infection or inflammation (for example Crohn's disease), trauma, surgical injury, radiation, malignancy, or complications of childbirth.

Symptoms depend on type but commonly include persistent drainage, foul-smelling discharge, local pain or swelling, recurrent infections, and, in urinary or reproductive tract fistulas, urinary or vaginal leakage. Diagnosis relies on clinical examination and imaging studies such as ultrasound, computed tomography (CT) with contrast, magnetic resonance imaging (MRI), or fistulography; endoscopic evaluation may be used for gastrointestinal fistulas.

Treatment aims to eradicate infection, close the abnormal tract when possible, and address underlying disease. Some simple fistulas heal with conservative management, while complex fistulas often require surgery or interventional procedures (eg, seton placement, fistulotomy, or tract repair). Prognosis varies with fistula type and underlying condition. See also fistula and related surgical terms.