BACKGROUND Primary immunodeficiency diseases (PIDs) are considered rare but are generally assumed to be more common in Middle Eastern countries. The prevalence and characteristics of PIDs are unknown in Oman. METHODS Sultan Qaboos University Hospital is the national referral center for PID in Oman during the study period. Patients were diagnosed and classified according to the clinical and la...

objective: common variable immunodeficiency (cvid) is one of the most frequent cases of primary immunodeficiency. it is likely that this heterogeneous disease is caused by several distinct genetic disorders. the activation-induced cytidine deaminase (aid) enzyme is involved in class switching, somatic hypermutation (shm) and processes associated with gene conversion in the germinal center. in o...

major histocompatibility complex (mhc) class ii deficiency is a primary immunodeficiency disease characterized by abnormality of mhc class ii molecules surface expression on peripheral blood lymphocytes and monocytes. clinical manifestations include extreme susceptibility to viral, bacterial, and fungal infections but the immunodeficiency is not as severe as scid (severe combined immunodeficien...

Autoinflammatory diseases are characterized by more or less spontaneous inflammation without inciting infection or autoimmunity. These can be either acquired or genetically determined. The latter –hereditary– autoinflammatory syndromes have been classified by some as primary immunodeficiencies: defects affecting the control of the innate arm of the immune system. Immunodeficiency syndromes, how...

One in 2,000 children younger than 18 years is thought to have a primary immunodeficiency disease. Antibody, combined B-cell and T-cell, phagocytic, and complement disorders are the most common types. Children with these diseases tend to have bacterial or fungal infections with unusual organisms, or unusually severe and recurrent infections with common organisms. A family history of primary imm...

Primary immunodeficiency disorders can predispose to certain malignancies but hitherto no such relation has been established for X-linked agammaglobulinaemia (XLA). We have diagnosed rapidly progressive colorectal cancer in 3 unrelated young adults with XLA. We could find no explanation for the tumours. Since the calculated incidence of rectosigmoid cancer is increased 30-fold in patients with ...

Background Chronic mucocutaneous candidiasis (CMC) is a heterogeneous group of primary immunodeficiency diseases (PID) characterized by chronic and recurrent infections of the skin, nails, and oropharynx, mostly caused by Candida sp. CMC is often associated with autoimmune and endocrine disorders. However, CMC may be the only or the main phenotype in patients with AD IL-17F and AR IL-17RA defic...