FY2027
MenuClose
Excludes1 pair

M72.8 vs N13.6

M72.8 and N13.6 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.

The official note, declared on M72.8
perirenal fasciitis with infection (N13.6)
M72.8

Other fibroblastic disorders

Billable
Chapter 13
Diseases of the musculoskeletal system and connective tissue
Section
M70-M79
Use when the record says
  • Abscess of fascia
  • Fasciitis NEC
  • Other infective fasciitis
Indexed under
  • Abscess › fascia
  • Contraction, contracture, contracted › fascia (lata) (postural)
  • Fasciitis › infective
  • Fasciitis › specified NEC
  • Fasciitis › traumatic (old)
N13.6

Pyonephrosis

Billable
Chapter 14
Diseases of the genitourinary system
Section
N10-N16
Use when the record says
  • Conditions in N13.0-N13.5 with infection
  • Obstructive uropathy with infection
Indexed under
  • Hydropyonephrosis
  • Pyohydronephrosis
  • Pyonephrosis
  • Hydroureter › with infection
  • Ormond's disease › with infection

These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.

Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027