Q79.1Other congenital malformations of diaphragm

Q79.1 is the ICD-10-CM diagnosis code for other congenital malformations of diaphragm. It belongs to category Q79 (congenital malformations of musculoskeletal system, not elsewhere classified), block Q65-Q79 (congenital malformations and deformations of the musculoskeletal system) and chapter 17 (congenital malformations, deformations, chromosomal abnormalities, and genetic disorders). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within Q79, choose Q79.1 (Other congenital malformations of diaphragm) only when documentation doesn't support a more specific option: congenital diaphragmatic hernia (Q79.0), Exomphalos (Q79.2), gastroschisis (Q79.3), prune belly syndrome (Q79.4), other congenital malformations of abdominal wall (Q79.5), Ehlers-Danlos syndromes (Q79.6), other congenital malformations of musculoskeletal system (Q79.8) and congenital malformation of musculoskeletal system, unspecified (Q79.9).

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.

In MS-DRG v44.0, it is part of the grouping logic for DRG 205 (Other Respiratory System Diagnoses with MCC, relative weight 1.8244) and DRG 206 (Other Respiratory System Diagnoses without MCC, relative weight 0.9257), in MDC 04 (Diseases and Disorders of the Respiratory System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It is exempt from present-on-admission (POA) reporting, so no POA indicator is required.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 756.6 (anomalies of diaphragm).