2027 ICD-10-CM Diagnosis Code G70.2Congenital and developmental myasthenia
ICD-10-CM Codes›G00–G99›G70-G73›G70
- Billable — Valid for Submission
- Risk Adjusts — HCC 196
- Chronic Condition
G70.2 is a billable ICD-10-CM diagnosis code for congenital and developmental myasthenia. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 73 through 74. Coders also document this condition as acetylcholine resynthesis deficiency. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Myopathies.
For Medicare Advantage risk adjustment, G70.2 maps to CMS-HCC Category 196 (Myasthenia Gravis without (Acute) Exacerbation and Other Myoneural Disorders) under the V28 model, adding a risk factor of about 0.516 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
G70.2 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.
Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Acetylcholine resynthesis deficiency
- Amyotonia congenita
- Congenital end-plate acetylcholine receptor deficiency
- Congenital myasthenic syndrome
- Congenital myasthenic syndrome with glycosylation defect due to ALG14 UDP-N-acetylglucosaminyltransferase subunit gene mutation
- Familial infantile myasthenia
- Genetically determined myasthenia
- Myasthenia gravis, juvenile form
- Myasthenic syndrome due to another disorder
- Pseudomyopathic myasthenia
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to G70.2: its own notes plus those printed at G70 and Chapter 6. A note printed at a category, block or chapter applies to every code under it.
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- 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)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
congenital G70.2
developmental G70.2
Oppenheim's disease G70.2
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Myasthenia Gravis
Myasthenia gravis, sometimes called MG, is a chronic (long-lasting) disease that causes weakness in your voluntary muscles. The voluntary muscles are the ones that you can control. They include the muscles you use for:
The full article covers:
- What is myasthenia gravis?
- What causes myasthenia gravis?
- Who is more likely to develop myasthenia gravis?
- What are the symptoms of myasthenia gravis?
- How is myasthenia gravis diagnosed?
- What are the treatments for myasthenia gravis?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert G70.2 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About G70.2Overview
What is the ICD-10 code for congenital and developmental myasthenia?
The ICD-10-CM code for congenital and developmental myasthenia is G70.2 (sometimes written as G702). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is G70.2 (Myasthenia gravis and other myoneural disorders) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report congenital and developmental myasthenia on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does G70.2 group to?
When congenital and developmental myasthenia is the principal diagnosis on an inpatient stay, it groups to MS-DRG 74, 73, with relative weights from 1.0172 to 1.5773 depending on complications. Higher weights mean higher Medicare reimbursement.
Can G70.2 be reported with A05.1?
Not as a rule. The Excludes1 note at G70, which applies to G70.2, lists "botulism (A05.1, A48.51-A48.52)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
What is the ICD-9 equivalent of G70.2?
Under the General Equivalence Mappings, congenital and developmental myasthenia converts to ICD-9-CM 358.8 (myoneural disorders NEC). The mapping is approximate, so confirm the match fits the documentation.
What HCC is G70.2?
G70.2 (congenital and developmental myasthenia) maps to CMS-HCC Category 196 (Myasthenia Gravis without (Acute) Exacerbation and Other Myoneural Disorders), commonly written as HCC 196, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 75 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 153.
Does G70.2 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, G70.2 adds a risk adjustment factor of about 0.516 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.248 to 0.642 depending on the payment segment). A more severe related category (HCC 195) supersedes it when both are reported. See the full factor table on the HCC 196 category page.
