As infection is characterized a situation in which the organism suffers from a disease caused by an “infectious” factor. These infectious factors may be microorganisms (bacteria, viruses, fungi, parasites) or toxic products of them. The diagnosis of infectious diseases is important for preventing their further transmission and, of course, for their treatment.
The dramatic evolution of Molecular Biology, both in theoretical basis and in laboratory techniques, has led to significant improvements in the diagnosis and clinical management of infectious diseases. Modern molecular methods for the diagnosis of infectious diseases differ from the classical microbiology techniques which are based on the growth of cultures from a patient sample or the detection of specific antibodies in the blood. The basic principle of molecular diagnostic techniques is the detection of the genetic material (DNA or RNA) of the microbe in the testing sample.
This type of diagnosis is particularly useful in cases of pathogenic microorganisms that cannot be cultured (eg HPV, hepatitis B virus) or in cases of slow growth pathogen microbes. The use of sophisticated molecular diagnostic techniques, such as e.g. PCR (Polymerase Chain Reaction) or Real-Time PCR, offers accurate and in time diagnosis. These techniques can detect the viral genetic material at very low levels that are not detectable by other serological tests.
Moreover, except from the higher sensitivity of the molecular techniques, the diagnosis of infections can be performed sooner , comparing to to the antibody detection method. In addition, molecular analysis is recommended, when classical serological methods give ambiguous results.
Molecular diagnostics is a state-of-the-art technology that must always be performed by highly qualified and trained personnel. The clinical significance of the results should always be interpreted by professionals with high scientific expertise, in collaboration with the physician in order to select the best treatment choice for the patient.