Here’s the code to use for essential hypertension. When patients are suffering from a hypertensive disease, selecting a diagnosis isn’t just a matter of choosing from a code or two to upload to your claim. There are several different types of hypertensive disease represented in the ICD-10 code book. Further, you’ll typically need to code to the 4th — or in some cases, 5th — character on these diagnoses. These 4th and 5th characters vary depending on the type of hypertensive disease the patient has. Read on for information on diagnosis coding for hypertensive diseases. Mark Essential Hypertension With I10 The first code in the “Hypertensive diseases (I10-I1A)” set is for hypertension. Not only is hypertension one of the most common ED diagnoses, it’s also one of the simplest: I10 (Essential (primary) hypertension). This is one of the few codes in the set that doesn’t require a 4th or 5th character. Next is hypertensive heart disease, which you’ll report with an I11.- (Hypertensive heart disease) code. 4th character: Use the 4th character in these diagnoses to denote with (0) or without (9) heart failure. From there, the code set goes to I12.- (Hypertensive chronic kidney disease). 4th character: Use the 4th character to mark the stage of the chronic kidney disease (CKD): with stage 5 chronic kidney disease or end stage renal disease (0) or with stage 1 through 4 CKD, or unspecified CKD (9). Use 5 Characters With These Hypertensive Diseases If a patient is suffering from hypertensive heart/kidney disease, you’ll report a code from the I13.- (Hypertensive heart and chronic kidney disease) set. 4th character: There are a pair of four-character codes in this set: I13.0 (Hypertensive heart and chronic kidney disease with heart failure and stage 1 through stage 4 chronic kidney disease, or unspecified chronic kidney disease) and I13.2 (Hypertensive heart and chronic kidney disease with heart failure and with stage 5 chronic kidney disease, or end stage renal disease). 5th character: There are also a pair of five-character codes in this set: I13.10 (Hypertensive heart and chronic kidney disease without heart failure, with stage 1 through stage 4 chronic kidney disease, or unspecified chronic kidney disease) and I13.11 (Hypertensive heart and chronic kidney disease without heart failure, with stage 5 chronic kidney disease, or end stage renal disease). Secondary Hypertension Has Several Sub-Diagnoses When a patient suffers from secondary hypertension, you’ll choose a code from the I15.- (Secondary hypertension) code set. 4th character: Unlike other fourth character options in this code family, these codes all have different descriptors. The codes are: Know Urgency, Emergency Definitions for Easier Coding When a patient is in hypertensive crisis, you’ll report a code from I16.- (Hypertensive crisis). 4th character: The 4th character in this option denotes the stage of the crisis. Here’s a look at your options: Urgency is a “severe increase in blood pressure without corresponding organ damage,” according to ICD-10. Emergency is “a severe increase in blood pressure with corresponding organ damage,” according to ICD-10. The final option in the hypertensive diseases is I1A.- (Other hypertension). 4th character: There’s only one 4th-character option in I1A.-: I1A.0 (Resistant hypertension).