Noticed some kind of infection or allergy around my 3 week old son buttocks area. doesn't look like diaper rash. we would like to know if that needs pediatrician attention immediately ?

Treat: Please see your pediatrician. Avoid harsh soaps and detergent. Use a baby diaper cream and change wet diapers promptly. Your Pediatric specialist may suggest other treatment.

Diaper rash: He should be seen by his pediatrician, but it isn't likely an emergency. Keep the diaper area clean and dry. A Yeast rash may show small bumps in the front of the diaper area. An Irritant rash looks like a sunburn particularly where the urine or stool caused irritation. They are treated differently, so your son should see his doctor.