Chédiak-Higashi Syndrome
Overview
Plain-Language Overview
Chédiak-Higashi Syndrome is a rare inherited disorder that affects the body's immune system and other cells. It primarily involves problems with white blood cells, which help fight infections, making people more prone to frequent and severe infections. The condition also affects the skin, hair, and nervous system, often causing light-colored hair, pale skin, and nerve problems. A key feature is the presence of unusually large granules inside certain cells, which interfere with their normal function. This disorder impacts the body's ability to respond to infections and heal properly, leading to serious health complications. It is caused by a genetic mutation that affects how cells transport materials inside themselves.
Clinical Definition
Chédiak-Higashi Syndrome is a rare autosomal recessive disorder caused by mutations in the LYST gene, which encodes a protein involved in lysosomal trafficking. The core pathology is defective formation and trafficking of lysosome-related organelles, leading to giant cytoplasmic granules in leukocytes and other cells. This results in impaired phagosome-lysosome fusion, causing defective microbial killing and increased susceptibility to infections, especially with Staphylococcus aureus and Streptococcus species. Clinically, it presents with partial oculocutaneous albinism, recurrent pyogenic infections, and a bleeding tendency due to platelet dysfunction. Neurologic abnormalities such as peripheral neuropathy and progressive neurodegeneration are common. The syndrome often progresses to an accelerated phase characterized by hemophagocytic lymphohistiocytosis, which is life-threatening without treatment.