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Updated: Jan 20, 2026
The Hydrogen Atom: Bohr Model and Balmer Series - Concept
Chediak-Higashi syndrome: Lessons from a single-centre case series
I Marques Carneiro1, A Rodrigues2, L Pinho3
1Department of Pediatrics Hospital Santa Maria (CHULN), Lisbon Academic Medical Centre, Av. Professor Egas Moniz, 1649-035, Lisbon, Portugal.
Background:
Chediak-Higashi syndrome (CHS) is a rare and potentially fatal autosomal recessive disease characterized by frequent bacterial infections, bleeding tendency, oculocutaneous albinism, photosensitivity and progressive neurologic dysfunction. Owing to the rarity of this condition, the objective of this study was to describe patients with CHS.
Methods:
Retrospective evaluation of patients followed in a paediatric tertiary centre of Allergy and Immunology of São Paulo, Brazil, between 1986 and 2018 with a confirmed diagnosis of CHS. Data were obtained from medical records. Demographic aspects, family history, clinical findings, laboratory data, diagnosis, treatment and outcome were described.
Results:
A total of 14 patients (five male) were included. Clinical manifestations were first recognized at a median age of two months (at birth-20 months). Median age at diagnosis was 1.7 years (0-5 years). All patients had recurrent infections. Albinism was present in 13 patients and silvery or light hair was present in 14. Seven patients developed hemophagocytic lymphohistiocytosis (HLH); the median age at the diagnosis of HLH was 5.7 years (2.6-6.7 years) and the median interval between the diagnosis of CHS and HLH was 3.3 years (0-5 years). Four of the most recently diagnosed patients underwent bone marrow transplantation (BMT). Nine patients are deceased, and one was lost to follow-up. The median age of death was 6.7 years (3.8-22 years). Five patients died of HLH, one of lymphoma, and three of infection. All the patients who had HLH before the year of 2000 died of HLH. The two most recently diagnosed patients with HLH were able to cure the HLH, although they died of other causes. Four patients are alive, three of them after successful BMT.
Conclusion:
Thirty years of follow up showed an improvement in the prognosis in patients with CHS. The better understanding of the underlying biological mechanisms of HLH allowed the standardization of management protocols, resulting in survival improvement. BMT is the only treatment that can change CHS prognosis, which emphasizes the need for early identification of the disease.
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