Understand These 4 Stages to Report Gout Flawlessly
Don’t forget to look at the inclusion terms. According to the American Academy of Family Physicians, “Gout is the most common inflammatory arthropathy, affecting more than 8 million Americans,” accounting “for approximately 7 million ambulatory visits in the United States annually.” The condition is caused by a buildup of uric acid, which, in turn, creates monosodium urate crystal deposits that produce inflammation and pain in the joints, most notably in the metatarsophalangeal joint of the big toe. From a coding perspective, assigning the correct ICD-10-CM code for gout is easy once you understand the four distinct stages of the condition. Here they are, along with some key tips to keep your gout coding on point. First, Know How to Code This Gout Precursor If a patient presents with pain or swelling in the joints, a provider will often order a serum uric acid test to determine the level of uric acid in the patient’s blood stream. Levels of greater than 7 mg/dL in men or 6 mg/dL in women indicate the presence of hyperuricemia, according to the National Center for Biotechnology Information. The correct code to use for hyperuricemia is E79.0 (Hyperuricemia without signs of inflammatory arthritis and tophaceous disease). Importantly, your provider will document this condition in the absence of inflammation in the joint; hence, the inclusion term of asymptomatic hyperuricemia for the code. Remember: Gout itself is listed as an Exludes1 condition for E79.0, so if the provider documents both hyperuricemia and any form of gout, you should only report the gout diagnosis code. Then, Understand Acute Gout Coding The next stage of gout occurs when the patient experiences intense joint pain, usually in the big toe. These flares, which can last up to two weeks, are coded to M10.- (Gout), and coding here will depend on the actual cause of the condition as follows: Remember, idiopathic means there is no known cause for the condition; so, if your provider does not document a cause, chances are you will default to M10.0- for cases of acute idiopathic gout. Remember, too, that gout can be caused by comorbidities such as “chronic kidney disease [CKD], hypertension, obesity, metabolic syndrome, diabetes, [and] hyperlipidemia,” according to the National Center for Biotechnology Information. So, gout caused by CKD and other renal conditions will code to M10.3-, while gout caused by other conditions will code to M10.4-. Following the Code first instruction to M10.4-, make sure you code the associated condition first. Inclusion terms to note: You may see the term “podagra” in your provider’s documentation. The term is a synonym for gout in general and can be applied to any of the M10.- codes. Other terms you should take note of are “gouty bursitis” and “primary gout,” which you’ll code to M10.0-. Don’t forget: All the M10- codes require 5th characters for anatomic location, with 5th character “7” indicating acute gout in the ankle and foot. They also require a 6th character to indicate laterality (“1” for right, “2” for left, and “3” for unspecified). Next, Avoid This Common Gout Coding Mistake When coding for gout, it is important you don’t confuse the condition with pseudogout, which, confusingly, is also a condition where crystals form in the joints. With pseudogout, however, the crystals affecting the joint are not urate crystals, but crystals composed of calcium pyrophosphate dihydrate. This condition is also referred to as chondrocalcinosis and is classified to the M11.2- (Other chondrocalcinosis) group. Know How to Code for Chronic Gout When the patient’s gout recurs and/or involves multiple joints, it may indicate chronic gout, which is coded to the M1A- (Chronic gout) group. Importantly, there is no guideline in ICD-10-CM that defines a condition as acute or chronic based on a timeframe. Guideline B.8 (Acute and Chronic Conditions) only tells you to code the acute (or subacute) condition first in a situation where a condition is described as both acute (or subacute) and chronic and there are codes for both “at the same indentation level.” This means the decision to define a condition as acute or chronic is up to your provider, and your coding needs to be dependent on their judgement. If you are habitually confused about whether to use an acute or chronic gout code, it may be a good idea to ask your podiatrist to begin noting acute and chronic in their documentation if they aren’t already. Like the acute gout codes, the chronic gout codes are arranged by causality using the same 4th characters. They also require the same 5th characters for site, and a 6th character for laterality. Unlike the acute gout codes, however, the chronic gout codes take a 7th character to indicate the presence or absence of tophi. Why? Unlike acute gout, “chronic gout is characterized by accumulations of urate crystals called tophi that can appear as bumps or nodules under the skin. A tophus can form in a joint, in the bursa that cushions and protects the joint, [or] in the bones or cartilage and under the skin,” according to the Arthritis Foundation®. So, it makes sense that only the chronic gout codes allow you to capture tophi information for reporting purposes. Last, Code for Additional Conditions Both the M1A.- and M10.- codes feature numerous Use additional code instructions to identify any associated or underlying conditions. When you do so, remember to report the gout secondary to the other condition. For example, you would report a patient who has chronic gout without tophi in the right ankle and foot due to arthropathic psoriasis with L40.5- (Arthropathic psoriasis) first, followed by M1A.4710 (Other secondary chronic gout, right ankle and foot, without tophus (tophi)). Bruce Pegg, BA, MA, CPC, CFPC, Managing Editor, AAPC
