Gastroenterology Clinical Lab

Our Clinical Lab Services

The Gastroenterology (GI) Clinical Lab at Nemours Children’s Hospital, Delaware is a CLIA-certified (CLIA#: 08D0984700) laboratory located in Wilmington, Del. We provide diagnostic tests related to digestive diseases and conduct research focused on diseases that affect pediatric patient populations. The GI Clinical Lab provides the following tests:

Small Bowel Biopsy

Disaccharidases are localized in the luminal (brush border membrane) of intestinal epithelial cells. They are responsible for the digestion of disaccharides. The activity of disaccharidases, including lactase, maltase, sucrase, palatinase and glucoamylase, can be determined from an intestinal biopsy. Increased enzyme activity does not have any known clinical significance; however, decreased enzyme activity results in a digestive defect of disaccharide, which may result clinically in osmotic diarrhea, crampy abdominal pain or gassiness. This decreased enzyme activity can be the consequence of generalized intestinal damage or can be an isolated (congenital or acquired) enzyme defect.

Sample Preparation:

The activity of disaccharidases can be determined from an intestinal biopsy with approximately 2 to 5 mg wet weight. Upon collection, the specimen should be placed in a small, tightly-capped plastic tube and immediately frozen on dry ice or stored in a freezer at -20°C to -70°C. The biopsy should not be placed on gauze or a toothpick, nor should any solutions be added. The sample should be shipped with enough dry ice to remain frozen. Enzyme activity may be affected if the sample thaws.

Duodenal Aspirate

Amylase, lipase, trypsin, chymotrypsin and elastase are secreted by the pancreas and are present in the pancreatic juice collected by duodenal intubation. Amylase, lipase, trypsin, chymotrypsin and elastase activities can be determined from duodenal fluid. Higher than normal enzyme activity does not have any known clinical significance. Lower enzyme activity can be the consequence of pancreatic damage (chronic pancreatitis, cystic fibrosis) or can be an isolated enzyme deficiency, which may be transient (in the first 5 to 6 months of life) or permanent (congenital enzyme deficiency).

Sample Preparation:

A minimum of 0.2 ml of fluid is required to analyze the five enzymes, protein content and pH. The sample can be a single fluid or multiple fluids. The fluid should be placed in a small, tightly-capped plastic tube. Keep the sample frozen and ship on dry ice.

Pepsin A is expressed exclusively in the gastric mucosa, thus detection of pepsin A in the airway of patients is a specific marker of airway aspiration. The GI Clinical Lab at Nemours offers a sensitive, reliable Elisa test to detect gastric pepsin in tracheal and bronchial secretions.  

Sample Preparation:

To collect tracheal secretion, attach a Luki trap to a suction catheter, pass the catheter down the endotracheal tube, and apply suction to the catheter as the catheter is withdrawn. If the secretion is too thick to be withdrawn, instill saline (2 cc) to the tracheal tube prior to aspirating the secretion.  

To collect bronchial secretion, use a standard collection protocol. Collect 1 to 2 cc of bronchial washing fluid in a plain specimen tube.  

Please avoid over-diluting the secretion with a large amount of saline during the collection. A minimum of 0.5 cc of fluid is required to determine gastric pepsin, protein content and pH. The airway fluid should be transferred to a small, tightly-capped plastic tube and frozen immediately after collection. Keep the sample frozen and ship on dry ice. 

Celiac disease (CD) is a permanent, immune-mediated, gluten-dependent enteropathy, which affects genetically predisposed individuals. A cascade of gluten-induced immune reactions is associated with the appearance of specific circulating autoantibodies in patients with CD. Serological tests measuring CD-specific antibodies are used for screening patients with suspected gluten-sensitive enteropathy as well as for monitoring dietary compliance. We are currently offering four serology celiac markers:  tissue transglutaminase antibody IgA (tTG IgA) and IgG (tTG IgG), and deamidated gliadin peptide antibody IgA (DGP IgA) and IgG (DGP IgG). A positive result indicates the presence of CD-specific IgA or IgG antibodies and suggests the possibility of certain gluten-sensitive enteropathies such as CD. The serological test results, in conjunction with clinical findings and other laboratory tests, will be used to aid in the diagnosis of CD and to monitor dietary compliance.

Sample Preparation:

This procedure should be performed with a serum specimen without any additives. Grossly hemolyzed or lipemic serum specimens should be avoided. Following collection, the serum should be separated from the clot. Store samples at room temperature for no more than 8 hours, refrigerated at 2°C to 8°C if longer than 8 hours, or frozen at -20°C if longer than 48 hours. A minimum serum sample volume is 0.3 cc.

Calprotectin is a calcium- and zinc-binding protein produced by polymorphonuclear leukocytes, monocytes and squamous epithelial cells. Fecal calprotectin elevates from five to several thousand times higher in organic diseases of the bowel compared with healthy individuals indicating intestinal inflammation, and it is a marker of inflammatory bowel disease. Calprotectin can be detected even in small (<1 g) random stool samples by Elisa assay.

Sample Preparation:

Random stool samples, loose or liquid, are acceptable. Stool samples from diapers should be avoided unless they have not contacted the diaper material. Samples (1 to 5 g stool) are placed in a screw-top clean vial without any additives (no preservative is necessary), and stored at 2ºC to 8ºC for up to 4 days before testing and at -20ºC if more than 4 days before testing, and shipped on dry ice.

The GI Clinical Lab at Nemours Children’s Hospital, Delaware also accepts samples for research studies and clinical trials. As part of the Gastroenterology Lab, we provide services to develop research projects for industry and research institutions.

Current research collaborators include Mayo Clinic, Florida; Cooper University Hospital, New Jersey; and Digestive Care, Inc., Pennsylvania.

Learn More About Clinical Trials at Nemours

Sample tubes labeled with patient information and accompanied by Sample Submission Form are to be shipped on dry ice (enough to last up to 48 hours) in a Styrofoam box (8x8 inches suggested or larger), and mailed to:

Nemours Children’s Hospital, Delaware
GI Clinical Lab, RCI Bldg. Rm 211
1600 Rockland Rd., Wilmington, DE 19803

Please do not send samples arriving on weekends and holidays.

For sample shipping and lab results, please call the lab at (302) 651-6893 or fax (302) 651-6881. 

For billing, call Denise Axsmith at (302) 651-6802 or email denise.axsmith@nemours.org. 

For scientific questions about the tests, please contact Zhaoping He, PhD at (302) 651-6853 or zhaoping.he@nemours.org.