DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Category · FY2027

G99 Other disorders of nervous system in diseases classified elsewhere

  • Header · not billable

G99 is not billable. The category heads 3 billable codes in FY2027: the 3 codes directly below it.

Index → code

  • Myelopathy (spinal cord)in (due to)disease classified elsewhere → G99.2

Where it sits

  1. Chapter 6 Diseases of the nervous system (G00-G99)
  2. G89-G99 Other disorders of the nervous system (G89-G99)
  3. G99 Other disorders of nervous system in diseases classified elsewhere
Billable codes
3
Subdivisions
3
CC / MCC codes
2 / 0
HCC V28 codes
1
New FY2027
0
Index entries
12

Codes in G99

  1. G99.0
    Autonomic neuropathy in diseases classified elsewhere
    BillableCC
    Excludes1 1, Code first 4

    Excludes1

    • diabetic autonomic neuropathy (E08-E13 with .43) E08 E13

    Code first

    • underlying disease, such as:
    • amyloidosis (E85.-) E85
    • gout (M1A.-, M10.-) M1A M10
    • hyperthyroidism (E05.-) E05
  2. G99.2
    Myelopathy in diseases classified elsewhere
    BillableCC182
    Excludes1 3, Code first 2

    Excludes1

    • myelopathy in:
    • intervertebral disease (M50.0-, M51.0-) M50.0 M51.0
    • spondylosis (M47.0-, M47.1-) M47.0 M47.1

    Code first

    • underlying disease, such as:
    • neoplasm (C00-D49) C00 D49
  3. G99.8
    Other specified disorders of nervous system in diseases classified elsewhere
    Billable
    Excludes1 4, Code first 3

    Excludes1

    • nervous system involvement in:
    • cysticercosis (B69.0) B69.0
    • rubella (B06.0-) B06.0
    • syphilis (A52.1-) A52.1

    Code first

    • underlying disorder, such as:
    • amyloidosis (E85.-) E85
    • avitaminosis (E56.-) E56

CC/MCC: as a secondary diagnosis, unless the principal diagnosis is on the code’s PDX exclusion list (MS-DRG v44 Appendix C; list on the code card).

Sources of each column.

Instructions

Notes that also apply

Chapter 6 instructions (Excludes2 8): printed on the chapter 6 page.

Index entries

  • Neuroavitaminosis → E56.9 [G99.8]
  • Paralysis, paralytic (complete) (incomplete)uremic → N18.9 [G99.8]
  • Myelopathy (spinal cord)in (due to)neoplastic disease → D49.9 [G99.2]
  • Myelopathy (spinal cord)in (due to)pernicious anemia → D51.0 [G99.2]
  • Degeneration, degenerativenervous systemamyloid → E85.4 [G99.8]
  • Myelopathy (spinal cord)in (due to)disease classified elsewhere → G99.2
  • Neuropathy, neuropathicperipheral (nerve)autonomicin (due to)hyperthyroidism → E05.90 [G99.0]
  • Neuropathy, neuropathicperipheral (nerve)autonomicin (due to)endocrine disease NEC → E34.9 [G99.0]
  • Neuropathy, neuropathicperipheral (nerve)autonomicin (due to)amyloidosis → E85.4 [G99.0]
  • Neuropathy, neuropathicperipheral (nerve)autonomicin (due to)metabolic disease NEC → E88.9 [G99.0]
  • Neuropathy, neuropathicperipheral (nerve)autonomicin (due to)gout → M10.00 [G99.0]
  • Neuropathy, neuropathicperipheral (nerve)autonomicin (due to)hyperthyroidismwith thyroid storm → E05.91 [G99.0]

NCHS Alphabetic Index. Index first, then the Tabular List.

Hierarchy