Summary of diagnostic tests for chronic diarrhea
| Stool test | Stool osmotic gap 46, Stool osmolarity 310 mOsm, Stool examination showed no WBCs or parasites seen, Stool antigen tests for Cryptosporidium, Giardia, and Rotavirus were negative, Fecal occult blood test was negative, Fecal fat measurement was normal, Fecal calprotectin was negative. |
| Blood test | Tissue Transglutaminase (tTG) IgA and IgG were negative, Vasoactive Intestinal Polypeptide 60 pg/mL, Gastrin level 300 pg/mL, Zinc level 44 mcg/dL, Morning cortisol level 19.7 mcg/dL, TSH 10.1 mIU/mL, Free T4 0.95 pg/mL, HIV screening was non-reactive. |
| Urinary test | Urine 24-hour 5-Hydroxyindoleacetic Acid (HIAA) 2.5 mg. |
| CT abdomen | Diffuse wall thickening of the colon concerning for colitis. |
| Esophagogastroduodenoscopy (EGD) | Non-bleeding esophageal ulcers, acute gastritis, and non-bleeding duodenal erosions. |
| Colonoscopy | Diverticulosis in the entire colon and a 5 mm polyp. |
| Gastric biopsy | Mild chronic superficial gastritis with no intraepithelial lymphocytosis, parasites, or granulomas. The immunohistochemical stain failed to demonstrate Helicobacter pylori. |
| Duodenum biopsy | Duodenal ulcer with acute duodenitis with no dysplasia or malignancy seen. |
| Colon polyp biopsy | Tubular adenoma that was negative for dysplasia. |
| Random colon biopsy | Benign colonic mucosa, negative for chronic active colitis and microscopic colitis. |
| Microbiology | Stool culture showed 4+ enteric flora, Duodenal aspiration culture showed 2,000 CFU/mL of enteric flora |