Abstract
Background : X-linked hyper-immunoglobulin M (XHIGM), a primary
immunodeficiency syndrome caused by mutations in the CD40 ligand gene,
presents with recurrent respiratory infections in pediatric patients. We
aimed to evaluate the spectrum of clinical features and respiratory
pathogens in pediatric patients with XHIGM in China.
Methods: We retrospectively reviewed
seven pediatric patients who were
diagnosed with XHIGM and received follow-up treatment at the
Guangzhou Women and Children’s
Medical Center between January
2010 and January 2021. We determined their clinical characteristics,
causative pathogens, and prognosis by performing peripheral
immunological and genetic tests.
Results: The majority of respiratory infections in four of the
seven patients were caused byTalaromyces marneffei . Two
patients had viral infections caused by cytomegalovirus (CMV) and human
adenovirus. One patient had a mixed infection caused byPneumocystis carinii and CMV. Except for one child who died of
respiratory failure, the other six patients survived with regular
infusions of intravenous immunoglobulin (IVIg) during the follow-up
period. Six patients had reduced antibody levels, especially IgG, IgA,
and IgE levels. Increased serum IgM levels were detected in four cases,
and three cases presented normal IgM levels at onset. All children were
diagnosed with XHIGM with CD40LG variation. Three novel mutations
were identified in the present study.
Conclusions: Our study suggests that fungi and viruses are
important pathogens causing respiratory infections in children with
XHIGM. In endemic areas, children with T. marneffei infections
have abnormal Ig levels in their peripheral blood, suggesting the ease
of early gene detection in these patients.