Introduction:
Hyper-IgM syndrome is an inborn error of immunity that predisposes to recurrent, prolonged, and opportunistic infectious processes. It is caused by different mutations, the most frequent being associated with the CD40 ligand.
Case presentation:
An 8-year-old male, with a history of 7 previous hospitalizations since 1 year of age due to septic shock, neuroinfection, gastroenteritis, community-acquired pneumonia, septic arthritis, and oral candidiasis. History of brother deceased at 3 months due to infection. History of taking immunoglobulin levels in 2018 that reports low IgG and high IgM. Last hospitalization in July 2022, diagnosed with osteomyelitis and oral candidiasis.
Immunology was consulted for family history, as well as a new immunoglobulin profile with low IgG and high IgM levels, hyper IgM syndrome is suspected, support was requested from the National Institute of Pediatrics where low expression of CD40 ligand was reported.
Management was started with intravenous human gammaglobulin at 400 mgkg/month, as well as antibiotic prophylaxis with trimethoprim, sulfamethoxazole and itraconazole. Currently without new infectious and stable pictures.
Discussion:
Hyper IgM syndrome is characterized by the inability to perform immunoglobulin isotype switching . As a consequence, these patients present decreased levels of IgG and IgA and normal or elevated levels of IgM.
The most common clinical manifestations are recurrent bacterial infections. Diagnosis is established based on clinical suspicion, family history, immunoglobulin levels, and genetic sequencing.
The dissemination of the clinical presentation of this immunodeficiency is relevant for the knowledge of these diseases, in order to make an opportune diagnosis of the pathology, as well as to initiate an adequate treatment and prevent complications, which will translate into a favorable prognosis and an improvement in the quality of life of these patients.