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Common skin conditions
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Work contributed to the skin disorders discussed in this quiz.
For each of the twelve cases, study the image(s) and then answer the questions. You can click on the image to view a larger version if required.
Each case should take approximately 2 minutes to complete. There is a list of suggested further reading material at the end of the quiz.
Make a diagnosis.
Open and closed comedones due to chloracne. Exposure to agricultural sprays (historical).
What is the patient's likely occupation?
Agricultural worker.
Chloracne is the hallmark of chemical poisoning due to exposure to halogenated hydrocarbons including dioxins. It is characterised by macrocomedones, nodules and cysts in unusual sites such as behind the ear. Chloracne may be associated with hyperhidrosis, porphyria cutanea tarda, type 2 diabetes and neurological symptoms. Chloracne is now rare, but was occasionally seen in factory workers manufacturing agricultural chemicals.