Pseudo-negative serum protein electrophoresis due to IgM aggregation in a patient with Waldenström macroglobulinemia
Year: 2026
Type: article
Study design: Case Report
Abstract: RATIONALE: Waldenström macroglobulinemia (WM) is a type of immunoglobulin M (IgM)-secreting lymphoplasmacytic lymphoma primarily caused by the accumulation of clonal lymphocytes, lymphoplasmacytes, and plasma cells. The monoclonal IgM proteins secreted by these cells result in high blood viscosity. PATIENT CONCERNS: A 79-year-old male presented with anemia lasting 10 months accompanied by edema in both lower limbs and testicles. DIAGNOSES: After a series of tests, including serological testing, serum protein electrophoresis, and genetic testing, the patient was ultimately diagnosed with WM. INTERVENTIONS: The patient received a red blood cell suspension transfusion and targeted therapy with zanubrutinib. OUTCOMES: The patient's dizziness and fatigue symptoms improved, no new blood blisters developed, and the anemia resolved. LESSONS: This case highlights that clinicians should consider lymphomas such as WM in the differential diagnosis for elderly patients with refractory anemia that progressively worsens. Also, note that IgM aggregates in WM patients can cause false-negative electrophoresis results.
Source: Medicine
Authors: Hanhan Xie, Enping He, Hui Quan, Shaocheng Zhang
Institution: Chengdu Medical College
Language: English
Subfield: Genetics
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $1,950
OpenAlex ID: W7212289299
