ICD-10-CM 2027
ICD-10 code for lung undeveloped
Congenital hypoplasia and dysplasia of lung
From the official ICD-10-CM alphabetic index entry “Undeveloped, undevelopment › lung”. Page updated September 29, 2026.
About coding lung undeveloped
The ICD-10-CM code for lung undeveloped is Q33.6 (Congenital hypoplasia and dysplasia of lung).
Within Q33 (congenital malformations of lung), Q33.6 is specifically for congenital hypoplasia and dysplasia of lung. Related codes cover congenital cystic lung (Q33.0), accessory lobe of lung (Q33.1), sequestration of lung (Q33.2), agenesis of lung (Q33.3), congenital bronchiectasis (Q33.4), ectopic tissue in lung (Q33.5), other congenital malformations of lung (Q33.8) and congenital malformation of lung, unspecified (Q33.9).
Don't report Q33.6 together with the conditions in its Excludes1 note: pulmonary hypoplasia associated with short gestation (P28.0).
As a secondary diagnosis it is an MCC (major complication or comorbidity), which can move an inpatient stay into the highest-paying "with MCC" MS-DRG of its family, unless the principal diagnosis excludes it.
Don't confuse with (Excludes1 for Q33.6)
- pulmonary hypoplasia associated with short gestation (P28.0)
Common questions about lung undeveloped ICD-10 codes
What is the ICD-10 code for lung undeveloped?
- Q33.6 — Congenital hypoplasia and dysplasia of lung.
Is Q33.6 billable?
- Yes. Q33.6 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can Q33.6 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict Q33.6 as a principal diagnosis.
Is Q33.6 a CC or MCC?
- Q33.6 is an MCC (major complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.