Small-intestinal Biopsy

A small-intestinal biopsy is a procedure in which small samples of tissue are removed from the lining of the small intestine for microscopic examination. In routine diagnostic practice, samples are commonly obtained from the duodenum, the first part of the small intestine, during an upper gastrointestinal endoscopy. A pathologist then examines the tissue to assess the structure of the intestinal mucosa and the types and distribution of cells within it .^1,2

Small-intestinal biopsy can reveal abnormalities that may not be apparent from the surface appearance of the intestine during endoscopy. Histological assessment can evaluate features such as the shape and height of intestinal villi, the depth of crypts, and the number and distribution of inflammatory cells within the epithelium and underlying mucosa. These findings can help identify or distinguish disorders that damage the small-intestinal mucosa .^1,2

The procedure is particularly important in the evaluation of celiac disease. Characteristic findings can include increased intraepithelial lymphocytes, crypt hyperplasia, and varying degrees of villous atrophy. These changes are not specific to celiac disease, however, so biopsy findings must be interpreted together with other clinical and laboratory information. Because intestinal abnormalities can be unevenly distributed, guidelines for suspected celiac disease recommend obtaining multiple samples from different parts of the duodenum .^1,2

Small-intestinal biopsy is distinct from endoscopy itself. Endoscopy allows a clinician to visually inspect the gastrointestinal surface and provides access for tissue sampling, whereas biopsy involves removing tissue for microscopic histological analysis .¹