Amino Acid Sequence ; Base Sequence ; Child ; Flow Cytometry ; methods ; Genes, X-Linked ; Hematopoietic Stem Cell Transplantation ; Humans ; Lymphocytes ; metabolism ; Lymphohistiocytosis, Hemophagocytic ; diagnosis ; genetics ; therapy ; Lymphoproliferative Disorders ; diagnosis ; genetics ; therapy ; Mutation ; Transplantation, Homologous ; X-Linked Inhibitor of Apoptosis Protein ; deficiency ; genetics ; metabolism

A clinical clerkship in medical informatics was introduced in the 5th year of medical school. One goal is computer literacy, which means comprehension of the hospital information system including security policy and privacy preservation. The other is information literacy; The students make presentations concerning the medical information system and information technology within approximately ten minutes. All participants were enthusiastic about preparing the presentation. Seventy percent of them acknowledged the significance of explaining persuasively to others what they studied and the usefulness of these skills developed in this clerkship in their future. This result implies the importance of the shift to information literacy.

OBJECTIVEX-linked lymphoproliferative disease (XLP), a genetic disorder characterized by immunodeficiency to Epstein-Barr virus (EBV) infection, has been linked to mutations in the SH2D1A gene. XLP patient displays EBV associated fulminant infectious mononucleosis or hemophagocytic lymphohistocytosis, hypogammaglobulinemia or malignant lymphoma. Here we report the clinical features, gene mutation and SAP expression on PBMCs of a Chinese patient with XLP and potential carriers.

METHODA 6 years old male patient and his maternal relatives were enrolled in this study. The patient was found to have with a renal Burkitt lymphoma on the right waist at 5 years of age by accident. His elder brother and a maternally related cousin both died of multiple systemic organ dysfunction syndrome (MODS) due to fulminant infectious mononucleosis (FIM) at the age of one year. The patient and his maternal relatives were subjected to detection of SAP expression on the PBMCs by flow cytometry and gene mutation analysis of SH2D1A by using PCR based on genomic DNA.

RESULTThe patient exhibited 536.9 copy/ml level of circulating EBV-DNA during remission. Sequence analysis showed that the patient harbored a nonsense mutation in exon 2 (C462T), resulting in a premature stop codon (Arg55X). His mother and some of the maternal relatives were proved to be carriers of this mutation. SAP expression from the patient was significantly reduced as compared to normal individual and the carriers.

CONCLUSIONWe identified a Chinese XLP case genetically. Assessment of SAP expression on PBMCs by flow cytometry seemed to be an effective rapid diagnostic method for this disease. Absence of EBV infection does not diminish the possibility of XLP.

Carrier Proteins ; genetics ; Child ; DNA, Viral ; blood ; Epstein-Barr Virus Infections ; complications ; Exons ; Herpesvirus 4, Human ; isolation & purification ; Humans ; Intracellular Signaling Peptides and Proteins ; genetics ; Lymphoproliferative Disorders ; complications ; genetics ; virology ; Male ; Mutation ; Pedigree ; Signaling Lymphocytic Activation Molecule Associated Protein

OBJECTIVEX-linked agammaglobulinemia (XLA) is the most common disorder among primary immunodeficiency diseases, which is caused by mutations in the cytoplasmic Bruton's tyrosine kinase (BTK) gene, characterized by lack of mature, circulating B lymphocytes, hypogammaglobulinemia, and recurrent bacterial infections. Mutations in BTK are highly diverse. In this study, genetic analysis was performed on BTK to realize the feature of gene mutation of XLA in Mainland of China.

METHODSSeven patients from 7 different families were enrolled in the analysis. RT-PCR was employed to reverse transcript total RNA and 8 couples of primers were designed for PCR. PCR products were sequenced and the mutation sites were identified.

RESULTSSeven completely different mutations were identified in the 7 patients. All the 7 mutations located at BTK coding region. Three of the 7 mutations were located in pleckstrin homology functional area, 2 mutations located in BTK area, and in other 2 cases at Src homology 2 and Src homology 3 regions, respectively. The mutations in 2 of 7 cases were in exon 18, and the others were in exon 2, 5, 6, 8 and 10, respectively. The types of mutation included 3 missense (L11P, I590F and Y591S), two nonsense (W281X, and Q234X) mutations resulting in premature stop codons. A 10-base pair nucleotides duplicated insertion located between the nucleotide 596 and 597 resulting in frameshift, and a 8 base pair deletion at the nucleotide position 472 resulting in frameshift. Four of the 7 mutations are novel mutation types and have not been reported. Four of 7 mothers were analyzed, 3 of them were carrier and 1 was normal.

CONCLUSIONThe patients enrolled in this study had classical clinical features of XLA. All the 7 identified mutations located at BTK coding region and 4 of them were novel mutations. Genetic analysis can be used for diagnosis of XLA and distinguish it from other hypogammaglobulinemia.

Adolescent ; Agammaglobulinemia ; diagnosis ; genetics ; Base Sequence ; Child ; China ; Codon, Nonsense ; DNA, Complementary ; Genetic Diseases, X-Linked ; diagnosis ; genetics ; Genotype ; Humans ; Male ; Mutation ; Mutation, Missense ; Protein-Tyrosine Kinases ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Young Adult