J93.12
Secondary spontaneous pneumothorax
J93.12 (also written J9312) is a billable ICD-10-CM diagnosis code for secondary spontaneous pneumothorax. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 7 codes in category J93 (Pneumothorax and air leak). The Alphabetic Index lists it under 1 entry. Its coding notes include a Code first instruction, a Use additional code instruction, 6 Excludes1 entries and 9 Excludes2 entries.
Code first
If the underlying condition listed here is present and known, sequence it first.
- underlying condition, such as:
- catamenial pneumothorax due to endometriosis (N80.B-)
- cystic fibrosis (E84.-)
- eosinophilic pneumonia (J82.81-J82.82)
- lymphangioleiomyomatosis (J84.81)
- malignant neoplasm of bronchus and lung (C34.-)
- Marfan syndrome (Q87.4-)
- pneumonia due to Pneumocystis carinii (B59)
- secondary malignant neoplasm of lung (C78.0-)
- spontaneous rupture of the esophagus (K22.3)
Use additional code
Add the listed code as a secondary code, if known.
Also from chapter/block level (7 notes)
Excludes1
Not coded here. The listed conditions generally should not be reported together.
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (9 notes)
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- smoke inhalation (T59.81-)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Care settings
How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.
Hospice: not accepted as primary
Not accepted as the principal diagnosis on a hospice claim (bill types 081x and 082x). The Integrated OCE returns an edit for this code.
Reason: Supplementary or additional code, not allowed as principal diagnosis.
Hospital CC
Counts as a complication or comorbidity (CC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 18 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.
Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix CNotes
Also from chapter/block level (1 note)
- When a respiratory condition is described as occurring in more than one site and is not specifically indexed, it should be classified to the lower anatomic site (e.g. tracheobronchitis to bronchitis in J40).
Alphabetic Index terms
Terms the official Alphabetic Index lists for this code. 1 entry