Eczema is an itchy skin condition, which often occurs on the arms or behind the knees.

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Other autoimmune forms include dermatitis herpetiformis, which causes itchy skin lesions, and gluten ataxia, which affects brain tissue, resulting in unsteady gait and lack of motor control.

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"Symptoms include flu-like symptoms like tiredness, general aches and pains, headaches and fever, as well as loss of appetite, nausea or vomiting, diarrhoea, abdominal pains, jaundice, very dark urine and itchy skin, " he said.

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The lesion on the skin starts out as an itchy pimple, which eventually becomes like a blister.

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Within 24 to 48 hours, an itchy red bump that resembles a bug bite develops, with a characteristic black area in the center where the skin is dying.

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