Major histocompability class I deficiency is a rare disease with remarkable clinical and biological heterogeneity. This deficiency consists of a group of autosomal recessive diseases caused by mutations in TAP1, TAP2, tapasin and β2 microglobulin, which are important for intracellular loading of antigens into MHC Class I molecules and stabilizing the complex. The clinical spectrum varies from complete absence of symptoms to life-threatening disease. We aimed to present the clinical, laboratory, genetic and follow-up results of 8 patients who were followed up with MHC Class I deficiency.
Patients' data were evaluated.retrospectively
8 patients from 4 families (F/M:4/4); median age of 16,5years (range 10-30y), median age of onset of symptoms 3,5years (range 1-17y), median follow up 12,5years (2-15y). We observed bronchiectasia in 7, skin lesions in 4, uveitis in and retinitis in 1 of patients. MHC Class I expresion was measured by flow cytometry very low. The mutation analysis performed and validated by next generation sequencing (NGS) and Sanger’s methods. We detected TAP1 mutation in six patients, TAP2 mutation in two patients. While one of two sibling was almost asymptomatic the other died due to sepsis caused by severe skin lesions. Overall survival is 87.5%.
MHC Class 1 deficiency should be consider in patients with skin lesions, sinopulmonary infections and bronchiectasis. The measure of HLA ABC expression by routine lymphocyte subgroup analysis allows the diagnosis. Clinical manifestation changes from patient to patient. The knowledge about bone marrow transplantation in MHC Class I deficiency is insufficient