G40.842 — KCNQ2-related epilepsy, not intractable, without status epilepticus
G40.842 is a billable, specific ICD-10-CM code for kcnq2-related epilepsy, not intractable, without status epilepticus. It is valid for submission on a claim.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- KCNQ2-related epilepsy NOS
Risk adjustment
G40.842 risk-adjusts. Under the CMS-HCC V28 model it maps to this category:
- HCC 201 Seizure Disorders and Convulsions0.245 RAF
Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score.
Medicare coverage
G40.842 is named in 7 Medicare coverage policies — 7 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A56612Billing and Coding: CT of the Head
- A56619Billing and Coding: Nerve Conduction Studies and Electromyography
- A56771Billing and Coding: Special Electroencephalography
- A56868Billing and Coding: Outpatient Speech Language Pathology
How G40.842 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to G40.842.
- Epilepsy, epileptic, epilepsia›KCNQ2-related
- Epilepsy, epileptic, epilepsia›KCNQ2-related›not intractable
- Epilepsy, epileptic, epilepsia›KCNQ2-related›not intractable›without status epilepticus
Related codes at this level
Codes that share G40.84. If G40.842 is not quite right, the correct code is usually one of these.
Questions about G40.842
- Is G40.842 a billable ICD-10-CM code?
- Yes. G40.842 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does G40.842 sit in the tabular list?
- Diseases of the nervous system (G00-G99), in the block Episodic and paroxysmal disorders (G40-G47).