Miloš Jeseňák, Zuzana Rennerová, Peter Bánovčin
Primary immunodeficiency disorders (PID) present big heterogeneous group of hereditary disturbances of immune system with estimated incidence of 1 : 2000 in the general population. PIDs are characterized as the cases in which particular or several components of immune system are missing, insufficient or working inappropriately. PIDs are classified according to the deficient part of immunity into immunodeficiency (IDS) of specific and non-specific immunity. PIDs of non-specific immunity can be divided into humoral IDS (complement IDS, approximately 1 % of all PIDs) and cellular – phagocyte IDS (apprx. 10 %). Disturbances of specific (acquired) immunity can be divided into 3 groups: predominantly humoral IDS (apprx. 70 % of all IDS), predominantly cellular and combined IDS (together apprx. 20 % of all IDS). It is important to note, that from this big group only those IDS are important, which are clinically manifested. This small group of clinically-significant IDS has big impact on the quality of life and prognosis of these children. Most of these diseases is clinically presented in the early childhood or during adolescence and therefore it is necessary to stress the education of all paediatricians about this complicated part of paediatric immunology. The most important PIDs are IDS of specific humoral immunity, which are presented since 6th month of life. Typical warning signs of suspected PID are: recurrent infections, especially respiratory (otitis media, sinusitis, tonsillitis, bronchitis, pneumonia), but also gastrointestinal and genitourinary; inappropriate therapeutical response to the conventionally applied antibiotics; infections caused by opportune micro-organisms; recurrent skin or soft tissue infections; organ abscesses; infections caused by unusual pathogens or in unusual localization; failure to thrive persistent or recurrent diarrhoea; chronic extensive oral or cutaneous candidiasis; severe, invasive infections (e.g. osteomyelitis, meningitis, sepsis); complications after vaccination (especially with attenuated vaccines); positive family history on PID or sudden unexplained death in the early childhood. All the children with one or more detected warning signs are indicated to the immunologic consultation. Before immunologic examination, blood cell count with differential leucogram, serum immunoglobulin levels of IgG, IgA, IgM, IgE and detailed documentation of frequency, type and severity of infections should be performed (e.g. diary). Although primary immunodeficiency disorders are rare, paediatrician meets them in its praxis and should not forget them. It is necessary to know basic warning signs of these diseases and simultaneously not postpone indicated immunologic examination.