ICD 10 Coding Alert

Keep your codes straight with a little clinical knowledge.

Food allergies may seem more common these days, but lumping food intolerances in the same boat can cause problems.

Check out these four common coding myths surrounding food allergies and intolerances, and then make sure you’re coding both conditions correctly.

Myth 1: ‘Allergy’ and ‘Intolerance’ Are Interchangeable

This myth is easily busted once you understand the etiologies of the two conditions. Basically stated: “food allergies, such as allergies to nuts or shellfish, are caused by a problem with your immune system. Food sensitivities or intolerances, such as reactions to wheat or milk, are caused by a problem with your digestive system,” according to the U.S. Department of Health and Human Services (HHS) (Source: www.womenshealth.gov/healthy-eating/food-allergies-and-sensitivities).

The difference between the two is critical from a clinical perspective. “An allergic food reaction can be severe or life-threatening, whereas food intolerance symptoms are generally less serious. For example, a true food allergy to peanuts could cause an anaphylactic reaction, while someone with a food intolerance, such as to lactose, will get diarrhea and experiencing bloating,” notes Donelle Holle, RN, president of Peds Coding Inc., and a healthcare, coding, and reimbursement consultant in Fort Wayne, Indiana.

From a coding perspective, this means must look to different chapters of ICD-10 to find the codes you need to describe a patient’s food allergy or sensitivity status.

Food allergy codes are easily found as they have their own subcategory of codes: Z91.01- (Food allergy status). Food intolerance codes, however, are a little more difficult to track down, though many of them can be found in the Diseases of the Digestive System chapter and coded to the K90.4- (Other malabsorption due to intolerance) ICD-10 subcategory.

Myth 2: Use the Milk Allergy Code for Milk Intolerance

Again, a knowledge of the condition’s etiology helps you understand the way the condition is coded. Patients who suffer from lactose intolerance “cannot break down sugar in dairy products due to a deficiency in the enzyme lactose,” Holle explains. Because of this, the code is categorized in the Endocrine, Nutritional and Metabolic Diseases chapter of ICD-10 and not in the Diseases of the Digestive System chapter.

This means you should use a code that is specific to lactose intolerance from the E73.- (Lactose intolerance) codes. It also means you should not use Z91.011 (Allergy to milk products). This is reinforced by the Excludes1 note to Z91.011, which tells you should not code Z91.011 with a code from E73.-.

Myth 3: Use the Celiac Disease Code When Coding Gluten Sensitivity

This myth comes from confusion over synonyms and over the similarities between the conditions. Both gluten sensitivity and celiac disease share common characteristics: In both, the body responds negatively to the gluten protein, which is found in food made using cereal grains such as wheat, oats, rye, and barley. But the two conditions differ in their effects on the human body, with gluten sensitivity causing minor, short-term symptoms such as stomachaches and bloating, and celiac disease causing such long-term health problems as malabsorption and bowel damage.

That’s why you must choose carefully between two different diagnosis codes in situations where a patient is affected by an adverse reaction to gluten. You’ll use K90.0 (Celiac disease) if your practitioner documents it, and K90.41 (Non-celiac gluten sensitivity) for gluten sensitivity that is less serious. Just be sure to look for the celiac and non-celiac designations.

Expert coding tip: The K90.4- (Other malabsorption due to intolerance) codes have an Excludes2 instruction that allows you to code both celiac and non-celiac gluten sensitive enteropathy and lactose intolerance (K90.0, K90.41, and E73.-) together when your practitioner documents them.

Myth 4: Peanut Allergy Code Works for all Nut Allergies

This time, a knowledge of plant biology helps to dispel this myth, though a close reading of the ICD-10 code synonyms will also tell you all you need to know.

Peanuts are legumes, not nuts; they are not related to tree nuts, despite their name. Therefore, it’s obvious that you should use Z91.010 (Allergy to peanuts) exclusively for patients who are allergic to peanuts. This is reinforced by the synonym for Z91.018 (Allergy to other food), which tells you the code can be used for allergies to nuts other than peanuts. And the absence of an Excludes1 note for both codes emphasizes that it is possible for a patient to be allergic to both peanuts and tree nuts.