ICD-10 Code D81.819 – Biotin-dependent carboxylase deficiency, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D81.819 – Biotin-dependent carboxylase deficiency, unspecified
What it is
This code identifies a biotin-dependent carboxylase deficiency when the specific enzyme defect is not documented. It points to an inherited metabolic disorder affecting enzymes that require biotin to function properly.
Clinical signs
Clinical features vary; refer to documentation. Commonly reported findings may include metabolic decompensation, neurologic symptoms, feeding problems, or developmental delay, depending on the specific enzyme involved.
When to use this code
Use this code when the record confirms biotin-dependent carboxylase deficiency but does not name the exact subtype. It is also appropriate when the clinician documents a suspected or unspecified form and no further detail is available. You should code the documented diagnosis, not a presumed enzyme defect.
Do not use for
Do not use this code for isolated biotin deficiency or for other hereditary metabolic disorders without documented biotin-dependent carboxylase involvement. Check documentation if the record names a specific carboxylase deficiency.
Coding tip
Capture the most specific documented subtype first; use D81.819 only when the chart leaves the deficiency unspecified.