What are the less common causes of mouth ulcers?
Infections can cause mouth ulcers. Herpes simplex often leads to widespread mouth ulcers in children and some adults. Other less common viral and bacterial infections may cause mouth ulcers, but this is rare. Mouth ulcers can be caused by anaemia and occasionally by other blood disorders and some skin or gastrointestinal diseases. Sometimes the mouth ulcers are the only sign of an underlying disease.
