Optional medical device diagnostics – depending on the results of the medical history, physical examination, laboratory diagnostics, etc. – for differential diagnostic workup
- Esophago-gastro-duodenoscopy (EGD; examination method of the upper part of the digestive tract: esophagus-gastro-duodenum) with collection of small intestinal biopsies* * (small intestinal suction biopsy; collection of at least six biopsies from different sections of the duodenum, including the bulbus duodeni), to confirm the diagnosis – this examination method has significance in the diagnosis of celiac disease, disaccharide intolerance, and some rarer forms of malabsorption
- Deep duodenal biopsy* * (villous atrophy beyond the Treitz band).
- Lactose H2 breath test* – on the day of testing, a baseline value is first obtained from exhaled breath. This is followed by the administration of 200 ml of a lactose solution, and then a breath sample is obtained regularly every 10 minutes to determine the concentration of H2 in exhaled air.The total duration of the examination is 3-4 hours; in patients with celiac disease, a secondary lactase deficiency can often be detected.
* Instructions for performing the examination!Do not eat carbohydrate-rich meals the day before the examination and prefer meals that are fiber-free.No eating or smoking should be done from 5:00 p.m. on the day before, and no drinks from 10:00 p.m.* * Duodenal biopsy can be omitted if the following conditions are met [ESPGHAN (European Society for Paediatric Gastroenterology, Hepatology and Nutrition) guideline]:
- Anti-TG (transglutaminase) IgA [>10-fold above the normal limit].
- Endomysium antibody (EMA) titer [positive in a second, separately drawn blood sample]
Important notes
- Obtaining duodenal (“duodenum-related”) histology (fine tissue examination) must be done promptly to celiac disease serology and symptomatology. No gluten-free diet must be present at the time the biopsies (tissue samples) are taken.
- According to one study, for a definite diagnosis of celiac disease, one should prefer the distal duodenum (part “distant” from the duodenum) and rather avoid the bulbus duodeni (upper part of the duodenum) as a biopsy site (site of tissue sampling). This is contrary to recommendations in the latest guidelines!
- Notice:
- Histological (fine tissue) examination is not a gold standard and is prone to error.
- The presence of histologic signs of enteropathy in isolation is not sufficient for the diagnosis of celiac disease! It must always be backed up by serological evidence.
- Individuals identified by screening may be completely asymptomatic despite pronounced villous atrophy!
