Otolaryngology Coding Alert

Question: A patient diagnosed with hyperthyroidism was found to have an additional single thyroid nodule during an exam. The physician did not specify that it was a goiter. What ICD-10 code(s) would we apply?

New York Subscriber

Answer: A single thyroid nodule, on its own, codes as E04.1 (Nontoxic single thyroid nodule). However, since the patient was diagnosed with hyperthyroidism, you can use the ICD-10 index by searching Nodule -> Thyroid -> Toxic or with hyperthyroidism -> E05.20 (Thyrotoxicosis with toxic multinodular goiter without thyrotoxic crisis or storm). In this instance, the correct (and only) code to use is E05.20.

For clarity: The term goiter, as defined by The American Thyroid Association, “refers to the abnormal enlargement of the thyroid gland.”  By this definition, the description of a simple thyroid nodule meets the criteria for a goiter. However, ICD-10 coding relies exclusively on the wording of the diagnosis. So even if some words have interchangeable meanings, it’s important not to code a particular symptom or disease if the index does not lead you directly to it.