Coding Counts

Autoimmune diseases cause the body to produce antibodies that attack its own tissues, leading to deterioration, and in some cases destruction, of tissue.

Many autoimmune diseases that carry a higher risk to the patient’s health are defined in ICD-10 nomenclature, but codes are not narrowed down to one particular section.

Type 1 Diabetes

Age can be misleading with Type 1 diabetes. Don’t let a patient’s age determine your code selection since either type of diabetes can occur at almost any age. You should also remember that diabetes can come with multiple complications, and ICD-10 guidelines let you use as many codes within a particular category as you need to accurately indicate an individual’s health status.

When coding diabetes with manifestations, make sure you assign the appropriate additional digits needed to identify the type of complication.

ICD-10 Code

Description

E10.1 – E10.11

Type 1 diabetes mellitus with ketoacidosis with or without coma

E10.2 – E10.29

Type 1 diabetes mellitus with kidney complications

E10.3 – E10.37

Type 1 diabetes mellitus with ophthalmic complications

E10.39

Type 1 diabetes mellitus with other diabetic ophthalmic complication

E10.5 – E10.59

Type 1 diabetes mellitus with circulatory complications

E10.6 – E10.69

Type 1 diabetes mellitus with other specified complication

E85.0 – E85.9

Amyloidosis

Heart Conditions

If there is a causal relationship between hypertension and a heart condition, a code from I50.- or I51.4-I51.9 must be assigned to a code from category I11 (Hypertensive heart disease). If there is no causal relationship between hypertension and the heart condition, they must be coded separately. Sequence the codes according to the circumstances of the encounter.

Rheumatoid Arthritis (RA) is a chronic autoimmune disease that progresses over time. It’s characterized by pain, swelling, and inflammation in the joints and surrounding tissues. It can also affect other organs in the body.

Rheumatoid arthritis with rheumatoid factor without organ or systems involvement

M05.8**

Other rheumatoid arthritis with rheumatoid factor

M05.9**

Rheumatoid arthritis with rheumatoid factor, unspecified

Rheumatoid Arthritis without Rheumatoid Factor

ICD 10 Category

Category Description

M06.0**

Rheumatoid arthritis without rheumatoid factor

Other Rheumatoid Arthritis

ICD 10 Category

Category Description

M06.1

Adult-onset Still’s disease

M06.2**

Rheumatoid bursitis

M06.3**

Rheumatoid nodule

M06.4

Inflammatory polyarthropathy

M06.8**

Other specified rheumatoid arthritis

M06.9

Rheumatoid arthritis, unspecified

**Add fifth character to designate site:

0 – unspecified site

1 – shoulder

2 – elbow

3 – wrist

4 – hand

5 – hip

6 – knee

7 – ankle and foot

9 – multiple sites

Add sixth character to designate laterality:

1 – right

2 – left

9 – unspecified side

Examples:

Patient 1: 89-year-old female referred to Rheumatology for shoulder pain and stiffness. Patient has pain and stiffness in multiple joints and complains of swelling in both wrists and hand. This has been going on for many months.

Physical withdrawal symptoms when substance has ceased or has been reduced

ICD-10 coding guidelines also define a hierarchy of reportable psychoactive substance use, abuse, and dependence code designations. When multiple terms (use, abuse, and dependence) are found in provider documentation, only one ICD-10 code should be reported:

If use and abuse are documented, report only the code for abuse.

If use and dependence are documented, report only the code for dependence.

If abuse and dependence are documented, report only the code for dependence.

If use, abuse, and dependence are all documented, report only the code for dependence.

The second major HCC based risk adjustment model is the RxHCC model. The RxHCC model was created for Medicare Part D and Medicare Advantage plans. This model, like the CMS HCC model, can predict benefit costs that the plan will be responsible for covering and adjust standardized payments based on the underlying health status of the plan’s members.

Rx condition categories describe major diseases and are broadly organized into body systems. Like the HCC model, they’re also categorized into hierarchies. This prevents multiple diagnoses in the same disease group from increasing the risk score when they shouldn’t.

An RxHCC risk score of 1.0 means a member covered by standard Part D Medicare benefits is expected to incur the average liability amount for prescription drugs.

These are some examples of RxHCC diagnoses that are commonly overlooked in yearly reports:

When selecting a code from this category, the documentation should indicate:

Type of angina

Associated spasm (if applicable)

Associated symptoms (if applicable)

According to the instructional notes, when coding angina equivalent, additional codes for associated symptoms should be added.

ICD-10 has combination codes that bundle atherosclerotic heart disease and angina. If the patient has both atherosclerotic coronary artery disease and angina, this should be reflected in the documentation and should be coded in one of these: