Each week, Live Science highlights an interesting medical case report in its Diagnostic Dilemma series. We describe the patient and their symptoms, the testing and history-taking that revealed their diagnosis, their course of treatment and their ultimate health outcomes. We also highlight what makes the case unique, whether it's the rarity of the diagnosis, the unusual constellation of symptoms, or a novel therapeutic approach.

How many Diagnostic Dilemmas have you read — and can you guess the diagnosis? Take our quiz that draws from the cases we highlighted in 2025 and see if you can figure out each patient’s ailment. Tell us how you got on in the comments below.

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