Although CMS guidelines as outlined in section 15506 of the Medicare Carriers Manual (MCM) state that "a physician or other appropriate source" must request a consultation, physicians may provide confirmatory consults (99271-99275) when a patient, the patient's family, or an insurer is seeking a second or third opinion prior to authorizing treatment - without another physician's written request.
If an insurer requests the consult to determine medical necessity prior to covering a procedure or service, you should report the appropriate confirmatory consult code (99271-99275, as supported by documentation) with modifier -32 (Mandated services) appended.
For example, surgeon "A" provides a diagnosis of stomach cancer and recommends immediate surgical treatment to remove the malignant tissue. The insurer, seeking a second opinion before authorizing costly surgery, requests a confirmatory consult with surgeon "B." Surgeon "B" evaluates the patient, provides a written response (for the insurer) and reports the confirmatory consult level supported by documentation (e.g., 99274) with modifier -32 appended. He or she may also separately report any required diagnostic testing.