ICD-10 Codes

When we think of medical billing and coding, our first thought is of the coding systems that are critical to the process.

So what is an ICD-10 code anyway?

ICD-10, International Classification of Diseases- tenth revision, is used to report all healthcare diagnoses and conditions. Every disease/condition is translated from the word format into an ICD-10 code. This code is required when billing a claim as a way to report the patient’s disease, illness, injury, symptoms, and complaints. The ICD-10 is copyrighted by the World Health Organization (WHO) and the ICD-10 manual is updated yearly.

How are ICD-10 codes used?

ICD-10 codes are designed to provide a fuller understanding of all aspects of a patient’s condition.

For Example

 Let’s look at a diagnosis as simple as an allergic reaction; ICD-10 code T78.40. Depending on the specific condition you could use the following ICD-10 codes:

  •  Pollen  - code J30.1
  •  Peanuts - code z91.010
  •  Seafood - code z91.013
  •  Ragweed - code j30.0
  •  Drugs -code T78.40

These codes would further be expanded to provide specifics on the type of drug, what type of seafood, chronic or acute conditions, left or right, etc. As you can see, picking a code requires a higher level of information about the patient's condition; including how it occurred and what the patient was doing when it occurred. 

These codes tell the health insurance carrier everything about the patient’s encounter. So even though they were not present when the patient was seen, they are able to determine exactly why the patient was being treated.

This starts with careful, detailed documentation of every aspect of the patient’s reason for the visit:

  • The patient’s complaints.
  • When they started.
  • Duration.
  • Severity. 
  • What they were doing when it occurred.
  • If they’ve had it before.

This documentation is what will be used to determine which of the hundreds of ICD-10 codes are appropriate to use. ICD-10 codes are entered in field 21 of the CMS 1500 claim form.

ICD-10 is new

Prior to 10/1/2015, the coding system in place was ICD-9. So what has changed?

  • The new codes are alpha numeric codes.
  • The code changed from five positions to seven.
  • 13,000 codes under ICD-9 to 68,000 codes under ICD-10.
  • ICD-10 has been expanded to fully describe the condition/disease/injury.
  • Codes were added to reflect which side of the body.
  • Codes were added to reflect the patient’s trimester of pregnancy.
  • It expanded the system so we would not run out of codes.

The new codes would allow for a more in depth review of a disease and its treatments in order to improve the outcomes.

Diabetes Mellitus

E10 - E13.9 

In addition to being able to designate Type 1 from Type 2 Diabetes, we can now code for just about every other condition/symptom/complaint stemming from Diabetes that affects all parts of the body.


250   Diabetes Mellitus

Other codes were presented, but without the detail in ICD-10.

ICD-10 is the coding system in place effective 10/1/15

Source: www.cdc.gov

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