medical-coding

name	medical-coding
description	Use when a provider needs to find ICD-10-CM, CPT, or SNOMED CT codes for diagnoses and procedures, extract medical entities from clinical text using Comprehend Medical, or validate code accuracy against clinical documentation.

Medical Coding

When to use this skill

• Find the correct ICD-10-CM code for a diagnosis
• Look up CPT/HCPCS codes for procedures and services
• Search SNOMED CT codes for clinical concepts
• Extract medical entities from clinical notes (NLP)
• Validate that assigned codes match clinical documentation
• Determine code specificity (3rd, 4th, 5th, 6th, 7th character requirements)

MCP Servers Used

• AgentCore Gateway — for Amazon Comprehend Medical tools (entity extraction, ICD-10-CM/RxNorm inference)
• Bedrock Knowledge Base — for medical code lookup (ICD-10-CM, CPT, SNOMED CT code descriptions and relationships)

Workflow: Code Clinical Documentation

Step 1: Extract medical entities from clinical text

Use Gateway Comprehend Medical tools:

• detect_entities_v2 — extract conditions, medications, procedures, anatomy, and test/treatment/procedure entities
• infer_icd10cm — get ICD-10-CM code suggestions with confidence scores
• infer_rx_norm — map medication mentions to RxNorm concepts

Output per entity:

• Entity text, category, type
• Confidence score (0.0 - 1.0)
• Suggested codes with scores
• Traits (negation, diagnosis, sign/symptom)

Step 2: Search knowledge base for code verification

Tool: search_medical_codes

• Input: query (description of condition/procedure), code_type (icd10 | cpt | snomed | all)
• Output: matching codes with descriptions and relevance scores
• Use to verify Comprehend Medical suggestions and find more specific codes

Step 3: Determine code specificity

ICD-10-CM specificity rules:

• Codes must be assigned to the highest level of specificity
• Check if additional characters are required (4th, 5th, 6th, 7th)
• 7th character extensions: A (initial encounter), D (subsequent), S (sequela)
• Placeholder "X" required when 7th character applies but code is fewer than 7 characters

Step 4: Validate code selection

Cross-reference:

• Does the code description match the clinical documentation?
• Is laterality specified where required (right/left/bilateral)?
• Are combination codes used where applicable?
• Are manifestation codes sequenced correctly (etiology first)?
• Are "code first" and "use additional code" notes followed?

Step 5: Present coding results

For each code assignment:

• Code and official description
• Clinical documentation supporting the assignment
• Confidence level (from Comprehend Medical or knowledge base relevance)
• Any coding notes or sequencing requirements
• Alternative codes considered and why primary was selected

Code Format Reference

Code System	Format	Example	Description
ICD-10-CM	A00-Z99.xxx	M54.5	Low back pain
ICD-10-CM (7th char)	S00-T88.xxxA/D/S	S72.001A	Fracture, initial encounter
CPT Category I	5 digits	99213	Office visit, established
CPT Category II	4 digits + F	2022F	Dilated eye exam
CPT Category III	4 digits + T	0042T	Cerebral perfusion analysis
HCPCS Level II	Letter + 4 digits	J1745	Infliximab injection
SNOMED CT	Numeric (6-18 digits)	195967001	Asthma

Key Conventions

• Always code to the highest specificity supported by documentation
• Never assign a code without supporting clinical documentation
• Comprehend Medical confidence scores below 0.5 should be verified manually
• "Excludes1" means the two codes CANNOT be used together
• "Excludes2" means the condition is not included but CAN be coded additionally if documented
• Use the knowledge base to verify unfamiliar codes — Comprehend Medical can suggest outdated codes
• Sequencing matters: principal diagnosis first, then secondary diagnoses in clinical significance order