X-linked lymphoproliferative syndromes (XLP) are a collection of genetic disorders that primarily affect the immune system, specifically the body's ability to control and regulate the proliferation of certain immune cells called lymphocytes. These syndromes are inherited in an X-linked recessive pattern, meaning they predominantly affect males, although there have been rare cases reported in females.
XLP syndromes are caused by mutations in genes involved in immune system regulation, particularly the SH2D1A and XIAP genes. These mutations lead to the abnormal proliferation of lymphocytes and an impaired immune response to certain infections, particularly the Epstein-Barr virus (EBV). As a result, affected individuals are at a higher risk of developing severe or fatal complications from EBV infection, such as hemophagocytic lymphohistiocytosis (HLH) or lymphomas.
The symptoms of XLP syndromes can vary, but often include persistent or recurrent episodes of EBV infection, an increased susceptibility to other viral infections, abnormal blood cell counts, enlarged lymph nodes, liver and spleen enlargement, and various autoimmune disorders. XLP is typically diagnosed through genetic testing to identify specific mutations in the associated genes.
Management of XLP syndromes involves close monitoring of infections, early detection and treatment of complications, and in some cases, stem cell transplantation to replace the faulty immune system with a healthy one. Genetic counseling is also essential for affected families to understand the inheritance pattern and the risk of passing on the condition to future generations.
