Angie is a 19-year-old student who presents with one week of decreased vision in her left eye.

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<p>Angie is a 19-year-old student who presents with one week of decreased vision in her left eye.</p><p>She had mild febrile illness about a month ago, with low-grade fever, malaise and tender left axillary lymphadenopathy associated with an infected sore on her hand.</p><p>There was no associated headache, neck stiffness or rash.</p><p>The fever and malaise resolved, but she still has an enlarged axillary lymph node.</p><p>Angie is usually very well, with no past history of note, and takes no regular medications.</p><p>She lives with her parents, younger brother and a four-month-old “scratchy and nippy” rescue kitten.</p><p>On examination, vital signs are normal, and there is a tender 1cm left axillary lymph node.</p><p>Uncorrected visual acuity is 6/6 on the right and 6/60 on the left.</p><p>Pupils are equal at 4mm, but there is a left relative afferent pupillary defect.</p><p>Fundal examination (pictured) shows a congested and oedematous left optic disc with unclear borders and stellate exudates in the macula.</p>

Dr Kate Kelso is a GP and medical editor at Australian Doctor.