ICD-10 Code K63.822 – Small intestinal fungal overgrowth (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K63.822 – Small intestinal fungal overgrowth
What it is
K63.822 identifies small intestinal fungal overgrowth, a condition where fungi are present in excess in the small intestine. Use this code when the record specifically documents fungal overgrowth rather than a more general intestinal disorder.
Clinical signs
Clinical features vary; refer to documentation. Commonly documented findings include bloating, abdominal discomfort, gas, and other nonspecific gastrointestinal complaints, but you should code only when the diagnosis is clearly stated.
When to use this code
Use K63.822 when the provider documents small intestinal fungal overgrowth as the confirmed diagnosis or an active assessment. It may also apply when the note clearly links persistent gastrointestinal symptoms to this condition. If the documentation is vague, check documentation before coding.
Do not use for
Do not use this code for general abdominal pain, nonspecific dyspepsia, or suspected overgrowth without a documented diagnosis. It is also not the right choice for bacterial overgrowth or other specified intestinal disorders.
Coding tip
Verify that the record names fungal overgrowth specifically; do not infer it from symptoms alone.