[The immunological and molecular diagnostics of respiratory tract infections].

Diagnostic strategies in upper and lower respiratory tract infections include conventional procedures and the new molecular tools. Serology plays a role in certain viral and atypical infections of lower respiratory track but is not reliable in small children and in immunocompromised subjects. Antigen detection can be also carried out. If a potential pathogen is non detectable by simply assay or in severe or complicated lower respiratory tract infections, the use of molecular tools is highly indicated.