achlorhydria

Definition of achlorhydria

a-chlor-hydr--ia - Absence of HCl in stomach (condition of lacking {green water}); Achlorhydria is a pathophysiological condition in which the parietal cells of the stomach fail to produce and secrete hydrochloric acid (HCl). Gastric acid is essential for activating pepsinogen into pepsin (to digest proteins), killing ingested pathogens, and facilitating the absorption of vital micronutrients such as Vitamin B12, iron, and calcium. Achlorhydria is most frequently seen in the end stages of chronic autoimmune atrophic gastritis, chronic Helicobacter pylori infections, pellagra, pernicious anemia, or as a consequence of prior gastric bypass/resection surgeries and chronic proton pump inhibitor (PPI) therapy.

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ETYMOLOGY of abscess

• a-: Greek prefix meaning “without” or “absence of”.

• o-: Greek chloros meaning “green” (used chemically to denote chlorine).

• o-: Greek hydor meaning “water” (used chemically to denote hydrogen).

• -ia: Suffix meaning “condition of”.

• Literal Meaning: “Condition without hydrochloric acid.”

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Coding & Documentation Nuances

ICD-10-CM Application: Achlorhydria is classified under the Digestive System chapter. The specific code isK31.83 (Achlorhydria).

Sequencing & Etiology Rules: According to ICD-10-CM guidelines, if the achlorhydria is a manifestation of an underlying disease (such as autoimmune atrophic gastritis or pernicious anemia), the underlying condition should often be coded as well to provide a complete clinical picture.

Surgical Impact (ICD-10-PCS/CPT): While achlorhydria itself is a diagnosis, it may justify the medical necessity for diagnostic procedures like esophagogastroduodenoscopy (EGD) with biopsy (CPT 43239) or gastric pH monitoring.

Clinical Indicators To support the coding of achlorhydria, a medical coder should look for the following in the clinical documentation:

Gastric pH testing: Documentation of a fasting gastric pH consistently > 4.0 or > 5.0 (normal is 1.5 to 3.5).

Endoscopy (EGD) with biopsy: Pathology reports indicating severe gastric atrophy or destruction of parietal cells.

Laboratory findings: Elevated serum gastrin levels (hypergastrinemia), positive anti-parietal cell antibodies, or positive intrinsic factor antibodies.

Associated clinical diagnoses: Unexplained iron deficiency anemia, macrocytic anemia, or pernicious anemia.

Related Terms & Differentials Hypochlorhydria: A deficiency or abnormally low level of hydrochloric acid in the stomach, differing from achlorhydria which is a complete absence.

Hyperchlorhydria: An excess of stomach acid, often leading to peptic ulcer disease or seen in conditions like Zollinger-Ellison syndrome (the clinical opposite of achlorhydria).

Pernicious Anemia: An autoimmune condition that prevents the formation of intrinsic factor (necessary for Vitamin B12 absorption). It is a classic clinical consequence of the parietal cell destruction that causes achlorhydria.

Atrophic Gastritis: Chronic inflammation of the stomach lining causing the thinning of the gastric mucosa and the loss of gastric glandular cells, directly leading to achlorhydria.

Gastroparesis: Delayed gastric emptying. While it can co-occur with achlorhydria due to poor digestion, it specifically refers to the motility of the stomach rather than its chemical secretions.

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DERIVATIONS of achlorhydria

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Query functionality

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Med roots Appendix A Prefixes Appendix B Combining Forms Appendix C Suffixes Appendix D Suffix forms