Case Presentation:

A 49–year–old man presented with 7 months of progressive ascending lower extremity weakness, numbness, and paresthesias. He also noted worsening right shoulder pain and swelling, gynecomastia, and leg edema. Physical examination was notable for right shoulder edema with decreased range of motion and soft, small testicles without masses. The lower extremities exhibited non–pitting edema, symmetric distal motor weakness, areflexia, and diminished sensation in a stocking–glove distribution. Laboratory results revealed a platelet count of 566,000/mL, total protein 9.3 g/dL, albumin 3.3 g/dL, and testosterone level 1.00 ng/mL (normal, 2.50–9.50 ng/mL). Hemoglobin, creatinine, luteinizing hormone, estradiol, and prolactin levels were within normal range. Serum protein electrophoresis revealed a monoclonal IgG lambda gammopathy of 4.0 g/dL with serum free light chains confirmed by immunofixation. Serum cryoglobulin levels were negative. CSF protein level was 222 mg/dL (normal, 15–45 mg/dL) with normal cell count. Electromyography demonstrated a demyelinating sensorimotor polyneuropathy with lower extremity denervation. Skeletal survey and MRI showed a 20–cm expansile lytic lesion in the right proximal humerus with chest wall invasion and right axillary lymphadenopathy. A core biopsy disclosed neoplastic plasma cells consistent with plasmacytoma. PET scan was without other osseous lesions, and cross–sectional imaging demonstrated mild splenomegaly. Bone marrow biopsy showed 7% plasmacytosis. Fat pad biopsy and echocardiogram revealed no signs of amyloidosis. A vascular endothelial growth factor (VEGF) level was 189 pg/mL (normal, 31–86 pg/mL). He received dexamethasone, radiotherapy, and melphalan followed by autologous hematopoietic stem cell transplant for treatment of POEMS syndrome.

Discussion:

POEMS syndrome (Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal protein, Skin changes) is a rare disorder thought to be caused by overproduction of cytokines such as VEGF. Although polyneuropathy and a monoclonal plasma cell disorder are required for diagnosis, patients may have many and seemingly unrelated clinical signs and symptoms that involve myriad systems (e.g., bone lesions, extravascular volume overload, thrombocytosis, and elevated CSF protein level). These additional symptoms differentiate POEMS syndrome from similar diseases like multiple myeloma, Waldenstrom’s macroglobulinemia, amyloidosis, and cryoglobulinemia. In the case of this patient, correct and timely diagnosis was dependent on the hospitalist’s synthesis of numerous physical and laboratory findings.

Conclusions:

This case of POEMS syndrome and its protean manifestations illustrates the importance of pattern recognition in the diagnosis of syndromic disorders. The hospitalist should be aware of this condition and consider POEMS in patients with polyneuropathy and evidence of a monoclonal plasma cell proliferation.