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Quantification of the Immunosuppressant Tacrolimus on Dried Blood Spots Using LC-MS/MS
Published on: November 8, 2015
Asymmetric bilateral demyelinating optic neuropathy from tacrolimus toxicity
Sriram Venneti1, Heather E Moss, Marc H Levin
1Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.
Journal of the Neurological Sciences
|November 30, 2010
Summary
Tacrolimus (FK 506) toxicity can cause optic nerve demyelination and vision loss, even with normal drug levels. This histopathologic description highlights a rare complication of long-term immunosuppressive therapy.
Area of Science:
- Neuro-ophthalmology
- Transplant medicine
- Toxicology
Background:
- Tacrolimus (FK 506) is a calcineurin inhibitor widely used post-transplantation.
- Prolonged tacrolimus use can lead to various toxicities, but optic nerve involvement is rare.
- Visual loss is a concerning symptom requiring thorough investigation.
Observation:
- A patient with a history of cardiac and renal transplantation developed progressive, asymmetric bilateral visual loss.
- Orbital MRI revealed an enlarged left optic nerve with gadolinium enhancement.
- Histopathologic examination of the optic nerve biopsy showed extensive demyelination.
Findings:
- The demyelination was not associated with vasculitis, neoplastic, or infectious causes.
- Tacrolimus toxicity was implicated despite therapeutic drug levels.
- This represents the first histopathologic description of tacrolimus-induced optic nerve demyelination.
Implications:
- Optic nerve demyelination should be considered in patients on long-term tacrolimus therapy presenting with visual disturbances.
- This finding expands the known spectrum of tacrolimus-related neurotoxicity.
- Further research is warranted to understand the mechanism and incidence of this adverse effect.
