For practical purposes, gastric pH and endoscopy should be done in someone with suspected<unk> . Older testing methods using fluid aspiration through a nasogastric tube can be done, but these procedures can cause significant discomfort and are less efficient ways to obtain a diagnosis. A complete 24-hour profile of gastric acid secretion is best obtained during an esophageal pH monitoring study.<unk>  may also be documented by measurements of extremely low levels of pepsinogen A (PgA) () in blood serum. The diagnosis may be supported by high serum gastrin levels (). The "Heidelberg test" is an alternative way to measure stomach acid and diagnose hypochlorhydria/achlorhydria. A check can exclude deficiencies in iron, calcium, prothrombin time, vitamin B-12, vitamin D, and thiamine. Complete blood count with indices and peripheral smears can be examined to exclude anemia. Elevation of serum folate is suggestive of small bowel bacterial overgrowth. Bacterial folate can be absorbed into the circulation. Once<unk>  is confirmed, a hydrogen breath test can check for bacterial overgrowth.
Achlorhydria
Hyperchlorhydria
Steatorrhea
Pseudodiarrhea
Aphagia
Polydipsia
Drooling
Constipation