Here's how to tell when you should use codes from the Z79 series. When the new ICD-10 codes take effect on October 1, 2017, you'll be dealing with a few more options for DKA coding than you've had previously. Many of the changes in Chapter Four, "Endocrine, nutritional and metabolic diseases," relate to diabetic ketoacidosis. 'DKA' occurs when the body breaks down fat instead of glucose to use for energy, producing ketones that make the blood more acidic. Recent studies have noted that the number of type 2 patients presenting with DKA has been increasing, which may be one reason for the new codes, experts note. "Prior to the revisions, the best coding option to describe a patient with type 2 DKA was E11.69" (Type 2 diabetes mellitus with other specified complication), says Suzan Hauptman, MPM, CPC, CEMC, CEDC, AAPC Fellow, senior principal of ACE Med Group in Pittsburgh. Coders should never be using E13.1 (Other specified diabetes mellitus with ketoacidosis) to report type 2 DKA-now or after the revisions take effect, Hauptman tells Internal Medicine Coding Alert. Code E13.1 has been and will continue to be incorrect. It is a nonbillable code. You'll find a new subdivision among the E11 (Type 2 diabetes mellitus) codes: E11.1 (Type 2 diabetes mellitus with ketoacidosis). This new subdivision includes two codes: E11.10 (... without coma), and E11.11 (... with coma). You'll find other DKA-related additions in code series E08 (Diabetes mellitus due to underlying condition...), E09 (Drug or chemical induced diabetes mellitus...), E10 (Type 1 diabetes mellitus ...), and E13 (Other specified diabetes mellitus ...). All three series contain XXX.1 (... with ketoacidosis) as a subdivision containing two codes: XXX.10 (... without coma) and XXX.11 (... with coma). Don't Miss the New Guidelines for Coding Insulin, Oral Hypoglycemics Coders should also take note of changes in the general guidelines for diabetes mellitus and secondary diabetes mellitus coding, says Rhonda Buckholtz, CPC, CPCI, CPMA, CDEO, CRC, CHPSE, COPC, CENTC, CPEDC, CGSC, who taught a class on this year's changes at AAPC's regional conference in Honolulu, Hawaii. The revisions clarify how to communicate medical management of diabetes. The first revisions appear in bold under Chapter 4.a.1, 'Diabetes mellitus and the use of insulin and oral hypoglycemics': "An additional code should be assigned from category Z79 to identify the long-term (current) use of insulin or oral hypoglycemic drugs. If the patient is treated with both oral medications and insulin, only the code for long-term (current) use of insulin should be assigned. Code Z79.4 should not be assigned if insulin is given temporarily to bring a type 2 patient's blood sugar under control during an encounter." Z79 is the "Long term [current] drug therapy" series. Similar instructions appear in bold under Chapter 4.a.6. for secondary diabetes mellitus. Resources: To read the complete list of ICD-10-CM changes, visit https://www.cms.gov/Medicare/Coding/ICD10/2018-ICD-10-CM-and-GEMs.html. To read the changes relevant to diabetes coding in ICD-10-CM Official Guidelines for Coding and Reporting, go to page 34-36 and look for the bolded text indicating changes for 'Chapter 4: Endocrine, Nutritional, and Metabolic Diseases (E00-E89)': https://www.cdc.gov/nchs/data/icd/10cmguidelines_fy2018_final.pdf.