Polyneuropathy: a poetic diagnosis.

Area of Science:

• Neurology
• Oncology
• Nephrology

Background:

• A 60-year-old female with end-stage renal disease secondary to IgA nephropathy, status post renal transplantation 9 years prior.
• Presented with subacute, progressive lower extremity weakness, significant weight loss, and fevers.

Observation:

• Physical examination revealed lower extremity weakness with lower motor neuron signs, clubbing, and cervical lymphadenopathy.
• Diagnostic workup showed thrombocytosis, elevated cerebrospinal fluid protein, and electromyographic evidence of diffuse demyelinating polyradiculopathy.
• Imaging identified a large lytic/sclerotic lesion in the right scapula, pericardial effusion, and borderline splenomegaly.

Findings:

• Pathological examination of the lymph node demonstrated Castleman-like changes.
• Biopsy of the scapular lesion revealed lambda-restricted plasma cells without detectable monoclonal protein peripherally or in the bone marrow.
• Diagnosis of POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes) with an associated plasmacytoma was established, with a suspicion of post-transplant lymphoproliferative disorder.

Implications:

• This case highlights a rare presentation of POEMS syndrome with plasmacytoma in a renal transplant recipient.
• The findings underscore the importance of a comprehensive diagnostic approach in patients with complex neurological and systemic symptoms.
• Further investigation into the interplay between POEMS syndrome, plasmacytoma, and post-transplant lymphoproliferative disorders is warranted.