Clinical microbiology examines disease-causing agents in humans. From birth, a bacterial flora begins to develop in various parts of the body within a short period, such as a week. These microorganisms, known as normal flora, serve as a barrier protecting the body against diseases. When examining disease material, efforts are made to detect microorganisms other than those that are part of the normal flora of the area being examined.
In clinical microbiology, samples commonly used include blood, urine, stool, throat swabs, and swabs from infected areas. Additionally, secretions and tissue samples from all body areas showing symptoms, as well as used medical materials, are employed to identify the bacteria causing the infection.
Clinical microbiology involves isolating and identifying the microorganism from patient material, detecting the microorganism through serological methods by identifying its antigens or antibodies, and selecting an appropriate antibiotic based on antibiogram tests to effectively treat the infection.
Disease-causing agents are studied within separate scientific disciplines such as Bacteriology, Virology, Mycology, and Parasitology. Depending on the type of material received in the laboratory, the area from which it was taken, and the suspected infectious agent, laboratory diagnostic methods must be chosen and applied comprehensively. The fact that the host is human necessitates prompt and accurate methods for these processes.
In diagnosing disease agents, clinical microbiology utilizes microscopic examinations, cultures, serological tests, and biochemical analyses. While identifying obligatory pathogens may be achieved with a single culture, opportunistic pathogens commonly found in nature require confirmation from at least two samples from patient material. Serological studies reveal the presence of the disease agent through titre increases or results exceeding certain thresholds. For some pathogens, the presence of specific immunoglobulins and their interactions within the serological profile provide guidance in diagnosing the disease.
