In my post about Pneumonitis cause, symptoms and treatment in children, I have mentioned that I will take my little boy to have a PPD skin test or mantoux test because he is thin, been sick lately for consecutive days and weight is not good at his age. PPD (purified protein derivative) skin test is a method used to diagnose tuberculosis (TB) or primary complex. The photo below is the actual forearm of my little boy where PPD extract was injected. I just marked a red circle at the area.
Using the rubbing alcohol my little boy’s forearm was cleansed then the PPD extract was injected under the top layer of his skin, causing a welt to form on the skin. The welt is gone in a few hours. According to the pediatrician, the reaction will takes 48 – 72 hours to develop so we must return to that time to have the area checked. The test determines if there is a significant reaction to the PPD test that is measured in millimeters of firm swelling (induration) at the area. If the wheal is less than 1cm or no reaction at all, then PPD skin test is negative. This is according to our pediatrician but you should carefully consult your pedia about it. After 72 hours we returned to the pediatrician to have it checked and we are glad that PPD skin test is negative.