my son was just born on March 9th, so he is almost 7 weeks old. He seemed to have a birth mark on his elbow. Today, my wife was putting a short sleeved shirt on him and noticed that under the mark there felt like what is a small lump. There is not a lump present on the other arm, under the other elbow. It does not seem to cause him discomfort. What could this be and what should the next course of action be?
Thank you for posting your question.birthmarks in child Chat Doctor.  The mark under the elbow that you mentioned might have evolved to become thicker and hence palpable.However, it is important to know what kind of birthmark (hyperpigmented/pigmented/hairy etc.) that you are talking about, which could help us rule out any other cause. By and large it seems to be a benign occurrence and the only thing that needs to be done is keeping a watch for similar lumps on other parts of body or an increase in size of the existing lump. If so, a medical consultation would be advisable. Also rule out some trivial local injury that may have caused a temporary swelling under the elbow. If you need any more advice regarding this, do write back.