Filgrastim-Induced Crescentic Transformation of Recurrent IgG2λ GN

Area of Science:

• Nephrology
• Hematology
• Immunology

Background:

• Proliferative glomerulonephritis with monoclonal IgG deposits is an emerging entity.
• Its association with hematologic malignancies requires further elucidation.
• Granulocyte colony-stimulating factor (G-CSF) is used for hematopoietic progenitor cell mobilization.

Observation:

• A young man presented with slow-progressing proliferative GN and monoclonal IgG2λ deposits.
• He developed recurrent GN post-kidney transplant and a plasma cell neoplasm 9 years later.
• G-CSF administration for stem cell mobilization coincided with severe crescentic transformation of the GN.

Findings:

• The patient experienced rapid allograft failure following G-CSF treatment.
• This suggests G-CSF may exacerbate pre-existing GN in patients with monoclonal IgG deposits.
• A potential link between G-CSF, GN, and plasma cell neoplasms is indicated.

Implications:

• This case underscores the importance of considering hematologic malignancies in proliferative GN with monoclonal IgG deposits.
• It raises concerns about the use of G-CSF in patients with underlying renal disease and potential plasma cell neoplasms.
• Further research is needed to understand the pathophysiologic role of G-CSF in GN exacerbation.