Multiple myeloma in remission complicated by bone marrow granulomas

Area of Science:

• Hematology
• Infectious Diseases
• Histopathology

Background:

• Granulomas appear in 1-2% of biopsies, often linked to infections (50%) or hematologic disorders (25%) like multiple myeloma.
• Toxoplasmosis can induce bone marrow granulomas in immunocompromised individuals.
• Long-term remissions in multiple myeloma are occasionally observed.

Observation:

• A 56-year-old female with IgG(kappa) multiple myeloma, in remission for 5 years, presented with bone marrow epithelioid non-caseating granulomas.
• No clinical symptoms or abnormal lab tests were noted, and the patient had no relevant medication history.
• Serological tests were negative for other granuloma-inducing conditions, except for positive Toxoplasma gondii IgG antibodies.

Findings:

• Treatment with azithromycin and pyrimethamine led to the disappearance of bone marrow granulomas.
• Simultaneously, anti-Toxoplasma IgG antibody titers significantly decreased.
• This suggests a causal link between toxoplasmosis and granuloma formation in this multiple myeloma patient.

Implications:

• Bone marrow granulomas are diagnostic indicators for opportunistic infections.
• Bone marrow biopsy is crucial for diagnosing such conditions.
• Azithromycin shows promise in treating toxoplasmosis-induced granulomas.
• Comprehensive clinical, histopathological, and serological follow-up is essential for diagnosing granuloma etiology.