L99
Other disorders of skin and subcutaneous tissue in diseases classified elsewhere
L99 is a billable ICD-10-CM diagnosis code for other disorders of skin and subcutaneous tissue in diseases classified elsewhere. It is part of the FY2027 code set, effective October 1, 2026. The Alphabetic Index lists it under 5 entries. Its coding notes include a Code first instruction, 3 Excludes1 entries and 10 Excludes2 entries.
Code first
If the underlying condition listed here is present and known, sequence it first.
- underlying disease, such as:
- amyloidosis (E85.-)
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 (10 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)
- lipomelanotic reticulosis (I89.8)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
- systemic connective tissue disorders (M30-M36)
- viral warts (B07.-)
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: Manifestation code. Report the underlying condition first (see the Code first note).
Alphabetic Index terms
Terms the official Alphabetic Index lists for this code. 5 entries