A 2-year-old boy is brought to the clinic due to recurrent infections. Over the last year, the patient has had multiple skin and pulmonary infections requiring antibiotic therapy. Temperature is 37.2 C (99 F), pulse is 120/min, and respirations are 20/min. The patient has silvery hair. Eye examination shows horizontal nystagmus. The oropharynx is clear, and the neck is supple. Cardiopulmonary examination is unremarkable, and the abdomen is soft. The skin appears pale with scarring from previous infections. Peripheral blood smear is shown in the image below: This patient most likely has which of the following disorders?

Question

A 2-year-old boy is brought to the clinic due to recurrent infections.  Over the last year, the patient has had multiple skin and pulmonary infections requiring antibiotic therapy.  Temperature is 37.2 C (99 F), pulse is 120/min, and respirations are 20/min.  The patient has silvery hair.  Eye examination shows horizontal nystagmus.  The oropharynx is clear, and the neck is supple.  Cardiopulmonary examination is unremarkable, and the abdomen is soft.  The skin appears pale with scarring from previous infections.  Peripheral blood smear is shown in the image below:  This patient most likely has which of the following disorders?

Quizplus · Accepted Answer

11ec160b_3a6e_bd75_9249_293aaa24cb44_MD0001_00 This patient's peripheral smear shows giant cytoplasmic granules within neutrophils, a finding pathognomonic for Chédiak-Higashi syndrome (CHS), an autosomal recessive disorder in which lysosomal trafficking is impaired. Characteristic findings include the following: (Choice A) Ataxia telangiectasia is a DNA repair disorder characterized by immunodeficiency (eg, recurrent sinopulmonary infections), neurologic deficits (eg, ataxia, nystagmus), and telangiectasias of the skin and eyes. Giant cytoplasmic granules on peripheral smear would not be present. (Choice C) In patients with chronic granulomatous disease (CGD), neutrophils are unable to kill catalase-producing organisms (eg, Staphylococcus aureus) due to a deficiency of NADPH oxidase. CGD is not associated with oculocutaneous albinism or giant cytoplasmic granules. (Choice D) Gaucher disease is a lysosomal storage disorder that causes bone pain, hepatosplenomegaly, and pancytopenia. Tissue biopsies show macrophages with a crumpled-paper appearance due to glucocerebrosidase accumulation. (Choice E) Neutrophils in leukocyte adhesion deficiency are unable to adhere to vascular endothelium or migrate to sites of infection. Patients have recurrent skin infections and poor wound healing, but silvery hair, nystagmus, and giant granules are not seen. (Choice F) Wiskott-Aldrich syndrome is an X-linked disorder characterized by immunodeficiency (combined B- and T-lymphocyte deficiency), bleeding due to thrombocytopenia, and eczema (not seen in this patient). Small platelets are present on peripheral smear, and oculocutaneous albinism is not seen. Educational objective: Chédiak-Higashi syndrome is an autosomal recessive disorder affecting lysosomal trafficking that results in immunodeficiency, albinism, neurologic abnormalities (eg, nystagmus). Giant granules are seen within neutrophils. __________ References: Chédiak-Higashi syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/29939658)

A 2-Year-Old Boy Is Brought to the Clinic Due to Recurrent