The experienced hematologists at Mayo Clinic diagnose POEMS syndrome by combining information from various sources, including:
No single test establishes the diagnosis of POEMS syndrome. The overgrowth of plasma cells can often be detected by finding an abnormal protein in the blood or urine (a monoclonal protein), by an abnormality on a bone X-ray and/or a bone marrow biopsy.
Clinicians consider the condition to be a syndrome, meaning that several features must be present to make the diagnosis. Because POEMS syndrome is so rare, physicians who do not have experience with the disease may miss the diagnosis. Initially, people may have been told that they have the nerve problem CIDP (chronic inflammatory demyelinating polyneuropathy) without any known cause. Or they may have been told that they have multiple myeloma, a bone marrow cancer.
Some patients have a coexisting disorder, Castleman disease, which is an abnormality of the lymph nodes. Though the majority of patients have abnormal bone X-rays, most will not have bone pain.
In order to have the syndrome, patients do not need to have every feature. However it is important to identify incomplete POEMS syndrome because patients may be at risk to develop other symptoms later.