Splenic marginal zone lymphoma associated with chronic inflammatory demyelinating polyradiculoneuropathy: a case report.

Chronic inflammatory demyelinating polyradiculopathy (CIDP) is an acquired immune-mediated neuropathy characterized by progressive or relapsing-remitting proximal and distal weakness. Lymphomas are among various hematological malignancies associated with CIDP. Splenic marginal zone lymphoma (SMZL) is a rare, indolent B-cell non-Hodgkin lymphoma that classically presents with splenomegaly and cytopenia. The co-occurrence of SMZL and CIDP is extremely rare; the diagnosis thus presents a unique challenge both diagnostically and therapeutically. We report a 65-year-old male patient with progressive proximal weakness, night sweats, and splenomegaly. Investigations revealed pancytopenia with imaging studies confirming the splenomegaly. Further investigations, such as a bone marrow biopsy and histopathology of the spleen, were indicative of a hypocellular marrow and SMZL, respectively. Simultaneously, a diagnosis of CIDP was established based on clinical findings, as well as electromyography and nerve conduction studies. For CIDP, immunosuppressive therapy was initiated; however, no treatment was administered for SMZL due to its indolent nature. He showed partial neurological improvement with the treatment given for CIDP. This underlines the importance of treating both diseases. The rare association of CIDP and SMZL is presented in this case, highlighting the importance of a comprehensive diagnostic workup in patients with neurological and hematological abnormalities. Therefore, for the management of such patients, timely identification and appropriate therapeutic approaches will be necessary for an improved outcome.