Posts: 3,675,937
Threads: 734,344
Joined:
Sep 2021
Reputation:
5
A 3-year-old boy presents with recurrent bacterial and fungal infections primarily involving his skin and respiratory tract. Physical examination reveals the presence of oculocutaneous albinism. Examination of a peripheral blood smear reveals large granules within neutrophils, lymphocytes, and monocytes. The total neutrophil count is found to be decreased. Further workup reveals ineffective bactericidal capabilities of neutrophils due to defective fusion of phagosomes with lysosomes. Which of the following is the most likely diagnosis?
A.
Ataxia-telangiectasia
B.
Chédiak-Higashi syndrome
C.
Chronic granulomatous disease
D.
Ehlers-Danlos syndrome
E.
Sturge-Weber syndrome
Posts: 3,675,937
Threads: 734,344
Joined:
Sep 2021
Reputation:
5
The answer is: B
Chédiak-Higashi syndrome is an autosomal recessive disorder characterized by the abnormal fusion of phagosomes with lysosomes, which results in ineffective bactericidal capabilities of neutrophils and monocytes. These abnormal leukocytes develop giant intracytoplasmic lysosomes. Abnormal formation of melanosomes in these individuals results in oculocutaneous albinism. Most of these patients eventually develop an œaccelerated phase in which an aggressive lymphoproliferative disease, possibly the result of an Epstein-Barr viral infection, results in pancytopenia and death.
Ataxia-telangiectasia is a chromosome instability syndrome that is characterized by increased sensitivity to x-rays (causing a markedly increased risk of lymphoid malignancies), recurrent infections, oculocutaneous telangiectasias (dilated blood vessels), and cerebellar ataxia. Chronic granulomatous disease is an X-linked recessive disorder characterized by recurrent bacterial infections due to deficient NADPH oxidase. Ehlers-Danlos syndrome results from many different defects in formation of collagen and is generally characterized by fragile skin and hypermobile joints. Sturge-Weber syndrome is characterized by capillary-venous malformation of leptomeninges and superficial cortex of one cerebral hemisphere with ipsilateral port-wine stains (nevus flammeus) in the trigeminal region of the face.
Posts: 3,675,937
Threads: 734,344
Joined:
Sep 2021
Reputation:
5
Sturge-Weber syndrome is characterized by capillary-venous malformation of leptomeninges and superficial cortex of one cerebral hemisphere with ipsilateral port-wine stains (nevus flammeus) in the trigeminal region of the face.
