Pathogenetic mechanism of macular edema during a treatment with ibrutinib: a case presentation

Chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL) are low-grade non-Hodgkin lymphomas characterized by monoclonal B lymphocytes. Bruton tyrosine kinase inhibitors (BTKis) represent the first-line treatment for symptomatic CLL/SLL. Here we report a case of a patient with SLL treated with ibrutinib who developed macular edema as confirmed by optical coherence tomography (OCT). Tyrosine kinase inhibitors have been linked to macular edema, but it is a very rare adverse event, and the pathogenic mechanism underlying it remains uncertain. Reviewing the literature, we sought to identify possible off-target effects of ibrutinib that could contribute to this condition. Although some kinases are involved in inflammation, this does not explain the link between ibrutinib and macular edema. However, only the inhibition of one kinase, Fyn tyrosine kinase, may play a role by altering adhesions between retina cells and the extracellular matrix when deficient.