Punchama PacharnBoonchai BoonyawatNiramol TantemsapyaNualanong VisitsunthornOrathai JirapongsananurukMahidol UniversityPhramongkutklao College of Medicine2018-12-212019-03-142018-12-212019-03-142017-09-01Asian Pacific Journal of Allergy and Immunology. Vol.35, No.3 (2017), 166-170222886940125877X2-s2.0-85034586338https://repository.li.mahidol.ac.th/handle/123456789/42766© 2017, Allergy and Immunology Society of Thailand. All rights reserved. Wiskott-Aldrich syndrome (WAS) is a primary immunodeficiency disorder caused by mutations of the gene encoding WAS protein (WASp). A scoring system has been used to grade severity of the disease. However, the phenotype of the disease may progress over time, especially in children younger than 2 years of age. Here, we report a male child who presented with X-linked thrombocytopenia (XLT). Mutation analysis revealed a novel hemizygous 13-bp deletion (c.181_193delGCTGAGCACTGGA) on exon 2 of the WAS gene. This frameshift mutation resulted in a premature terminating codon at position 71 (p.A61fsX10). Molecular analysis of maternal DNA revealed a heterozygosity of the same mutation. The disease progressed to classic WAS within 8 months. Later, gastric varices as a consequence of Mycobacterium bovis infection in the spleen was detected. The rapid worsening of the disease may be due to the severe genotype of this patientMahidol UniversityImmunology and MicrobiologyArticleSCOPUS10.12932/AP0792