POEMS SYNDROME; A RARE DISEASE WITH MULTI-SYSTEMIC CLINICAL MANIFESTATION THAT OVERLAPS COMMON CONDITIONS LEADING TO CONFIRMATION BIAS

Case Presentation: We present a 40 year-women with a past medical history of untreated latent TB who presented to an outside hospital with progressive edema, ascites and was subsequently found to have diffuse lymphadenopathy with a benign biopsy, monoclonal gammopathy and a PET scan showing sclerotic lesions. She was transferred to our hospital for concern for pulmonary hypertension (PAH) that was confirmed by right heart catheterization. Ultimately, she was diagnosed with Scleroderma given scelrodactyly, Raynaud’s and a +anti-Scl-70 Ab. Her monoclonal gammopathy revealed two small IgA lambda M-spikes but a normal kappa/lambda ratio and no anemia or renal dysfunction. A review of her PET scan did not show increased metabolic activity in the sclerotic lesions. Hematology felt this presentation was most consistent with a monoclonal gammopathy of undetermined significance (MGUS) associated with her Scleroderma.She was treated with Epoprostenol for severe PAH and after initiation patient noted worsening of burning sensation in hands and feet. Two paracenteses then revealed a serum-ascites albumin gradient (SAAG) of 0.7 consistent with a non-portal hypertension etiology. Analysis of ascitic fluid was negative for malignancy or TB. The presence of burning pain prior to Epoprostenol raised concern for a peripheral neuropathy, plus a monoclonal gammopathy, sclerotic bone lesions, lymphadenopathy, and low-SAAG ascites led to consideration of POEMS syndrome. An elevated VEGF confirmed the diagnosis.

Discussion: POEMS syndrome (Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal protein, Skin changes) is a rare disease involving different systems of the body. Its diagnosis requires both mandatory criteria; polyneuropathy plus a monoclonal plasma cell disorder as well as one major criterion (osteosclerotic bone lesions, Castleman’s disease or elevated VEGF levels) and at least one of the minor criteria (organomegaly, endocrinopathy, skin changes, or ascites). Its clinical manifestations can be complex and challenging due to overlap with more common diagnoses.

Conclusions: This POEMS case highlights the tendency towards confirmation bias in patients with a new diagnosis of a rare disease. Our patient’s peripheral neuropathy was assumed to be a side effect of PAH medication initiated for her newly diagnosed Sclerodrema-associated PAH. It was not until later that it was recognized that her symptoms predated epoprostenol. Her low-level monoclonal gammopathy was attributed to her autoimmune disorder. Her low SAAG was inconsistent with portal hypertension but defining an alternative etiology for this was not initially successful. In retrospect, our patient met mandatory criteria, major criteria and minor criteria even before her VEGF returned elevated. As hospitalists we often focus on common diagnoses when treating common symptoms to improve the overall value of care but inconsistencies of our diagnosis with history or labs should highlight the possibility of confirmation bias and should alert the clinician to consider alternative/rare diagnoses.