 Welcome back to our USMLE Question of the Week. As always, we begin with the last sentence of the question to find out what this question is looking for. This patient most likely has which of the following types of immune deficiencies. A 10 year old female is brought to the pediatrician by her parents because of a low grade fever. The physician notes that the girl has pale skin and bright blue eyes, which the mother states has been present since birth. The physician diagnoses the girl with a Staphylococcal infection and prescribes her a course of antibiotics. Three months later, the child returns to the pediatrician with fever and a sore throat, which was diagnosed as a streptococcal infection. A review of the patient's medical records indicate that she has had repeated episodes of Staphylococcal and Streptococcal infections for her entire life. The patient most likely has which of the following types of immune deficiencies. So the key thing that we're looking for here is repetitive or increased susceptibility to Staph and Strap microbes. Looking at these answer choices, I would probably rule out E first and foremost because severe combined immune deficiency will increase our risk for more than just Staph and Strap microbes. I would also rule out Hyper IgM syndrome and I would rule out Chronic Granulomatous disease. I do remember Chronic Granulomatous disease does increase our risk for Staph infections, but it does not increase our risk for Strap infections because the problem is with microbes that create their own catalase. Therefore I am down between A and D. Pulling more information in from the question, the patient has pale skin and bright blue eyes, which is indicative of albinism. Chedicogashi is associated with lysosomes which are also associated with melanin, therefore my answer would be A, Chedicogashi syndrome. A is the correct answer as Chedicogashi disease is an inherited autosomal recessive disease. This is caused by a deficiency in lysosomes emptying phagocytic cells due to Defrex and the microtubular function. So patients with Chedicogashi disease often present with recurrent Streptococcal and Staphylococcal infections and the association here with albinism can be present because melanosomes are derivatives of lysosomes. As I said earlier, B, Chronic Granulomatous disease does increase susceptibility to Staph, but it's also to organisms like Candida due to the catalase organisms that they produce their own catalase. Furthermore D, selective IGA deficiency would increase our risk of sinus and lung infections, but that does not necessarily limit us to Staph and Strep. Finally, as I said earlier as well, our severe combined immunodeficiency increases our risk for bacterial, viral, protozoal and fungal infections.