Clinical Analysis Of A Case With Primary Immunodeficiency Disease Caused By Mutation Of STAT1 Gene And Literature Review

Objective: To analyze the clinical features of children with primary immunodeficiency disease caused by STAT1 gene mutations and to improve understanding,diagnosis and treatment level of primary immunodeficiency disease caused by gene mutations in clinical work.Method: A detailed analysis of medical history,clinical manifestations,auxiliary examination,diagnosis and treatment of a child with primary immunodeficiency caused by mutations in the STAT1 gene in our hospital,and related literature review.Result: The child 6-year-old male,main complaint“abnormal blood routine was found more than 3 month and fever for 6 days”.Combined with auxiliary examination and past history that he had multiple infections before,consindering the presence of “ pneumonia,leukopenia,thrombocytopenia,and anemia,liver insufficiency,type 1 diabetes,oral candidiasis,myocardial injury,hypoalbuminemia,etc.”.The main treatment methods included the anti-infection,the anti-viral and the anti-fungus,comprehensive treatment such as nutritional organs,increasing white blood cells and regulating blood glucose.But the child still had repeated high fever,liver and spleen significantly enlarged compared to the time of admission,hydrothorax and ascites appears and the index of infection increased progressively,so antibiotic was upgraded.At the same time,we were searching for the cause of the infections,such as bone marrow aspiration,rheumatic immunity and the virus series were normal,but the blood metagenomic second-generation sequence result showed "Mycobacterium tuberculosis infection,sequence number 13",basis on monitoring liver function isoniazid,pyra-zinamide and rifampicin were given as anti-tuberculosis treatment,the tem-perature gradually returned to normal,liver and spleen become smaller gra-dually and hydrothorax and ascites disappeared.The child has long-term repeated infection,thrombocytopenia and leukopenie,liver insufficiency,diabetes and so on,considering the possibility of primary immunodeficiency disease,at this time genetic result reported that“the STAT1 gene has one heterozygous mutation,which is a spontaneous mutation,”.Combing the(blood)tuberculosis infection,we recommended tuberculosis examinations(such as bronchoalveolar lavage)to the parents,they choosed discharge from hospital.Later the child was followed up by phone calls in a hospital in Shanghai.After treatment with anti-tuberculosis,anti-fungal,and antibiotics his condition improved.Now his condition is stable and he is taking intravenous human immunoglobulin every month as immune reconstitution therapy.Conclusion:1.When children had repeated long-term refractory infections,leucopenia and thrombocytopenia were the prominent manifestations with multiple pathogens and multiple organs involved at this time possibility of primary immunodeficiency should be considered and genetic testing should be performed as soon as possible to confirm the diagnosis.2.In clinical work when there is repeated infections and treatment is ineffective,pathogen should be detected.If pathogen detection is difficult by conventional methods then can consider metagenomic next-generation sequencing(m NGS)of blood or body fluid histo-cytopathology as an effective detection method.An effective detection method can guide the application of anti-pathogenic drugs and improve the therapeutic effect.3.Primary immunodeficiency disease caused by STAT1 gene mutation is a relatively rare disease,which is easy to be missed and misdiagnosed.We should raise our awareness and clinical attention to this disease.