Karnataka PGET Pathology MCQ Answer 1

The Correct answer is B

(1) defects in adhesion due to genetic deficiency of β2 integrins (LAD-1) or fucosyl transferase (LAD-2)
(2) defects in phagolysosome function (Chediak-Higashi syndrome)
(3) defects in microbicidal activity due to a genetic deficiency of the NADPH oxidase system (chronic granulomatous disease) or genetic deficiency of myeloperoxidase.

Chediak-Higashi syndrome (CHS), is a rare autosomal recessive disorder associated with an immune deficiency leading to increase susceptibility to infection and a life-threatening lymphoma-like syndrome.

A lack of natural killer cell function and a neutropenia may be found, with a prominent defect in formation of neutrophil granules.

The gene for CHS has been cloned, based on its homology to the murine gene responsible for the Beige phenotype that corresponds to the mouse CHS .

The CHS protein has structural features homologous to a yeast vacuolar sorting protein thought to be associated with vesicle transport.

In fact, the CHS abnormalities are not restricted to neutrophils and all cell types show some oversized lysosomes, the disease affecting thus several organ systems.

Category: Karnataka PGET 2007 MCQs