There are many different things which can cause a bloody nose or blood-streaked nasal mucous. In a child, a pediatrician
is the best physician to make an initial assessment and determine whether other physicians such as ear, nose, and throat (ENT) doctors
should become involved.
The skin lining the nasal passages is very thin and delicate which is what makes it prone to bleeding
with even minor irritation. Irritating factors can include cold/dry weather; seasonal or environmental allergies; or an infection that causes typical upper respiratory 'cold' symptoms. Some other common causes of bleeding from the nose include trauma or a foreign body (in a child, most often related to nose-picking).
Bleeding from the nose can also be caused by more rare conditions, including anatomical abnormalities; vitamin deficiencies; a connective tissue disorder; side effects from a medication; or a hematological disease.
In the absence of other symptoms, blood-streaked mucous in a child likely represents irritation of the nasal mucosa in the setting of a viral cold. However, because there are other things which can cause these symptoms, it is always best for a pediatrician to evaluate a child's symptoms. In the case of a bloody nose, this evaluation can help ensure that other health conditions are not missed as well as recommend ways to minimize nasal dryness and irritation.