A 4 month old male is brought to your office by his parents for a wellness check. They are concerned about his repeated bouts of eczema and recurrent infections. He has a complicated medical history significant for bloody diarrhea and hard to control epistaxis during the second month of his life. Your physical examination found a feeble baby with eczema, dry blood in the perinatal region and splenomegaly. You ordered some routine labs for this patient. Later that evening a technician from the laboratory called you to inform you of some ‘red flag’ lab results, which are a platelet count of 60000/ platelets/µL with reduced sized platelets in clumps. Concerned about the possibility of Wiskott Aldrich syndrome (WAS), you ordered a genetic test and it revealed a genetic defect on the short arm of the X-chromosome. In WAS patients, what is the most common finding at the time of diagnosis?
