Home Health ICD-9/ICD-10 Alert

Question: Would you please elaborate on the correct decision-making process for looking up neuropathic pain? A colleague tells me that, without any detail regarding the location or cause of the condition, one would use 355.9 (Mononeuritis of unspecified site). Is she right?

Answer: The International Association for the Study of Pain defines neuropathic pain as pain initiated or caused by a primary lesion or dysfunction in the nervous system. Patients may feel neuropathic pain as a burning or tingling sensation or as hypersensitivity to touch or cold. You have three options when coding for neuropathic pain. Mononeuritis results from damage to a single nerve which is often painful.

Given more detail, you might find an appropriate diagnosis in the codes related to causalgia, such as 354.4 (Causalgia of upper limb), 355.7x (Other mononeuritis of lower limb), 355.8 (Mononeuritis of lower limb, unspecified), or 355.9.

Other options include coding by the cause of the patient's pain. These could include phantom limb pain (353.6), postherpetic neuralgia (which you code by site), or reflex sympathetic dystrophy (337.2x). But again, you would need greater detail in the medical record to select one of these codes.

In your case, you don't have the details to use one of these specific codes. Even 355.9 specifies that the patient has mononeuritis, a detail your diagnosis doesn't include. So, absent greater specificity, you would report a more general diagnosis such as 729.2 (Neuralgia, neuritis, and radiculitis, unspecified).

Best practice: Because you have so many options for coding neuropathic pain, talk with the clinician to determine the best diagnosis for the patient. Also, when coding an unspecified site, always think twice. In home care, you should have the site of such pain documented based on the clinical assessment.