Guide to Rashes
Tiny red, brown or purple spots, about the size of a pin-prick, that appear under the skin are petechiae (also called purpura). These spots are flat and don't itch or blanch (turn pale) when you press gently on them. A child may have just a few spots or clusters of them, often appearing on the face, chest, stomach or feet.
Petechiae are caused when tiny blood vessels burst underneath the skin. Kids can develop them after a bout of coughing or vomiting, usually on the face. But widespread petechiae can be associated with serious disorders as well. These include idiopathic thrombocytopenia purpura (ITP), a blood-clotting disorder that may follow a viral illness, or meningococcal disease, which can cause meningitis, a bacterial infection of the lining between the brain and the skull, or meningococcemia, a widespread bacterial infection of the bloodstream.
It's important to see a doctor when your child has petechiae, especially if he hasn't been vomiting (which would indicate a less-scary virus), and the spots are below the chest. Blood tests can be performed to diagnose ITP or meningococcal disease.
The Hib vaccine will protect your child from meningitis, but there's not much you can do to avoid most other sources of petechiae.
Petechiae will fade on their own, but it's important to treat what's causing the spots. Ask your doctor about medications or therapies for vomiting, or a chronic or heavy cough. More serious underlying conditions may need to be treated in the hospital.