Pediatric autoimmune neuropsychiatric disorders with associated streptococcal infection investigation of MHC haplotypes

PANDAS is the acronym for pediatric autoimmune neuropsychiatric disorders related to streptococcal infections which is a newly defined disease. Its symptoms occurs in the childhood especially between 4-12 years. This illness occurs with a autoimmune mechanism after a Group A Beta Haemolytic streptococcus infection. Streptococcus bacteries have antigenic M, T, R proteins in their cell wall. M proteins are the most important pyogenes virulans factor for human diseases. In the Patient?s imune system, firstly B lymphocytes susceptible to M group of antigens kills them. After B lymphocyte activaton, some of the susceptible B lymphocytes pass over blood- brain barrier and associates with the cell membrane of neuron cells because of epitope mimicry and the loss of neurons in the part of the brain which is supposed for coordination of moving, care and also active memory cannot be compensate and neuropshychiatric signs are unavioidable. Because of neuropshychiatric disorders like PANDAS, in which immunulogical reactions directly trigger and/or has an important role for the disease, researchs are focused on immunology area. Exogen originated antigens showing molecular structure similarity to tissue antigens with a molecular mimicry mechanism, otoantibody synthesis based on genetic factors or regulation of immune response; particular MHC system (Major Histocompantibility Complex) haplotypes trigger otoimmune reactions in target tissues and organs. As a result, apoptosis mechanism occurs and unavoidable loss of functions are indicated. In our study, MHC haplotypes of PANDAS patients and association between HLA haplotypes are researched.Key words: PANDAS, OKB, İmmune System, HLA, MHC Antigens.