G70.80
BillableLambert-Eaton syndrome, unspecified
HCC Category Mapping
V28HCC 196 — Myasthenia Gravis/Myoneural Conditions and Guillain-Barre
0.402V24HCC 75 — Myasthenia Gravis/Myoneural Conditions and Guillain-Barre Syndrome
0.425ESRDHCC 75 — Myasthenia Gravis/Myoneural Conditions and Guillain-Barre Syndrome
0.000RxHCCHCC 153 — Myasthenia Gravis/Myoneural Conditions
0.000What This Code Means
Lambert-Eaton syndrome, a rare autoimmune disorder affecting the connection between nerves and muscles, causing muscle weakness that improves with activity.
Coding Tips
- •Use this code when Lambert-Eaton syndrome is diagnosed but not associated with another classified disease
- •If associated with malignancy or another condition, use G70.81 instead
Clinical Significance
Lambert-Eaton syndrome, unspecified is a rare autoimmune disorder targeting presynaptic voltage-gated calcium channels at the neuromuscular junction, causing proximal muscle weakness that characteristically improves with repeated use. It may be paraneoplastic or autoimmune in nature. Accurate coding is essential as it carries significant HCC value and may prompt cancer screening when paraneoplastic origin is suspected.
Documentation Requirements
- ✓Clinical features: proximal weakness improving with activity, autonomic dysfunction, hyporeflexia
- ✓Electrodiagnostic confirmation: incremental response on repetitive nerve stimulation
- ✓Voltage-gated calcium channel antibody testing results
- ✓Cancer screening results: chest imaging, PET scan to evaluate for small cell lung cancer
- ✓Distinction from myasthenia gravis documented
- ✓Provider's explicit diagnosis of Lambert-Eaton syndrome
Commonly Confused Codes
G70.81 — Lambert-Eaton syndrome in disease classified elsewhere should be used when associated with a specific underlying diseaseG73.1 — Lambert-Eaton syndrome in neoplastic disease should be used when associated with cancerG70.00 — Myasthenia gravis without exacerbation affects postsynaptic receptors and worsens with activity, opposite of Lambert-Eaton syndromeG70.89 — Other specified myoneural disorders is less specific and should not be used when Lambert-Eaton syndrome is diagnosed
Code Hierarchy
└G70Myasthenia gravis and other myoneural disorders└G70.8Other specified myoneural disorders└G70.80Lambert-Eaton syndrome, unspecified
└G70.80Lambert-Eaton syndrome, unspecified