Chédiak–Higashi syndrome

A 4-month-old boy presented with lymphadenitis and a history of recurrent ear and chest infections. His mother complained that he could not tolerate bright light; however, his developmental milestones had been met. He is the third child of Caucasian, non-consanguineous parents. Examination revealed that he was pale, with silvery white hair (top). There was no hepatosplenomegaly. A full blood count showed haemoglobin 11Æ4 g/dl, white blood cell 23Æ1 · 10/l (neutrophil count 12Æ3 · 10/l) and platelet count 406 · 10/l. The blood film showed abnormal granulation and vacuolation in neutrophils (bottom left), eosinophils and lymphocytes with cells containing giant granules. On resolution of the acute illness, he was mildly neutropenic (neutrophil count 1Æ1 · 10/l). Bone marrow examination demonstrated granulocyte precursors containing giant granules (bottom right), which stained positively with myeloperoxidase. Ophthalmic examination confirmed ocular albinism. The combination of oculocutaneous albinism and large abnormal granules in leucocytes is characteristic of Chédiak–Higashi syndrome (CHS). The patient remains well on prophylactic antibiotics and an unrelated donor search is underway in anticipation of stem cell transplantation. Of interest, his eldest brother has recently completed chemotherapy for acute lymphoblastic leukaemia but his general appearance and leucocyte morphology show no features of CHS.