E73.0 Congenital lactase deficiency

Billable ICD-10-CM code, FY2026.

MS-DRG index

Defines the logic of DRG(s) 391-392 in MDC 06.

Approximate ICD-9-CM (GEMs)

• 271.3 Intestinal disaccharidase deficiencies and disaccharide malabsorption (approximate)

Code annotations containing back-references to E73.0

Back-references to E73

• Type 2 Excludes: E74.3 Other disorders of intestinal carbohydrate absorption ("lactose intolerance (E73.-)")
• Type 2 Excludes: G11 Hereditary ataxia ("metabolic disorders (E70-E88)")
• Code First: G63 Polyneuropathy in diseases classified elsewhere ("metabolic diseases (E70-E88)")
• Type 2 Excludes: G71 Primary disorders of muscles ("metabolic disorders (E70-E88)")
• Code First: H42 Glaucoma in diseases classified elsewhere ("specified metabolic disorder (E70-E88)")
• Type 2 Excludes: K90.4 Other malabsorption due to intolerance ("lactose intolerance (E73.-)")
• Type 2 Excludes: N25.0 Renal osteodystrophy ("metabolic disorders classifiable to E70-E88")
• Type 2 Excludes: N25.81 Secondary hyperparathyroidism of renal origin ("metabolic disorders classifiable to E70-E88")
• Type 1 Excludes: P59 Neonatal jaundice from other and unspecified causes ("jaundice due to inborn errors of metabolism (E70-E88)")
• Type 1 Excludes: R79 Other abnormal findings of blood chemistry ("specific findings indicating disorder of carbohydrate metabolism (E73-E74)")
• Type 1 Excludes: Z91.011 Allergy to milk products ("lactose intolerance (E73.-)")

Diagnosis Index entries for E73.0

• Alactasia, congenital
• Deficiency, deficient › lactase › congenital
• Intolerance › disaccharide, hereditary

Nearby codes

• E73 Lactose intolerance
• E73.0 Congenital lactase deficiency (this code)
• E73.1 Secondary lactase deficiency
• E73.8 Other lactose intolerance
• E73.9 Lactose intolerance, unspecified