Mirabegron Flashcards
What medication was implicated in the case report?
Mirabegron.
What is mirabegron’s mechanism of action and its primary clinical use?
It is a β3-adrenoreceptor agonist used to treat overactive bladder.
What was the patient’s chief complaint in the case report?
A 4-week history of progressive central vision loss in the right eye.
How long had the patient been using mirabegron?
The patient had been on mirabegron for 4 years.
What key ocular findings were noted on Optical Coherence Tomography (OCT)?
Outer retinal atrophy, increased choroidal thickness, and hyperreflectivity in the right eye.
What did Fundus Autofluorescence (FAF) imaging reveal?
Central hypoautofluorescence surrounded by hyperautofluorescence, more prominent in the right eye.
What change in visual acuity was observed after discontinuing mirabegron?
The right eye’s visual acuity improved from 20/400 to 20/125.
How does the case report link mirabegron to choroidal changes?
Through the association of β3-receptor stimulation in the retina and choroid leading to increased thickness and pachychoroid-like changes.
Which pachychoroid spectrum disease was considered in the differential diagnosis?
Polypoidal choroidal vasculopathy (PCV).
Did the OCT imaging meet the typical diagnostic criteria for PCV in this case?
No, the patient’s OCT did not demonstrate the specific criteria recommended for PCV.
What is the significance of early detection in mirabegron-associated choroidopathy?
Early detection and cessation of mirabegron may help optimize final visual acuity and limit permanent damage.
What additional finding was noted regarding the patient’s genetics?
The patient was a heterozygous carrier for a USH2A mutation, which was not symptomatic.
Why is this case report considered unique in the literature?
It is the first to show both subjective and objective visual improvement after stopping mirabegron and the second to link mirabegron with choroidal changes.
What systemic condition is mirabegron primarily prescribed to manage?
Overactive bladder.
How do the side effects of mirabegron differ from those of antimuscarinic medications?
Mirabegron, as a β3-agonist, has a different side effect profile and potentially affects choroidal tissues, unlike antimuscarinics such as oxybutynin.
Which previous study finding supports the notion that mirabegron can alter choroidal thickness?
A study showed a significant increase in the thickness of the nasal subfoveal choroid after 4 months of mirabegron use.
What clinical intervention was taken after correlating the visual symptoms with mirabegron use?
Mirabegron was discontinued after discussion with the patient, her family, and her primary care physician.
What is the proposed mechanism by which mirabegron might induce choroidal changes?
Stimulation of β3-receptors in the choroidal and retinal endothelial cells can lead to increased cell invasion, proliferation, and subsequent choroidal thickening.
What imaging modality showed partial improvement following the cessation of mirabegron?
Fundus autofluorescence (FAF) images showed some improvement, while OCT findings remained largely unchanged.
What is the overall clinical recommendation derived from this case report?
Clinicians should consider early ophthalmologic evaluation for patients on mirabegron who develop visual symptoms, allowing prompt intervention.
