Screening for Acanthamoeba is mainly performed for the investigation of keratitis (corneal inflammation).
Acanthamoeba is an amoebian genus that includes both free-living and parasitic species. Free-living species are "bacteriophages", that is, they obtain the nutrients and energy they need from the consumption of bacteria while parasitic species infect animal organisms, sometimes causing disease. Species of the genus Acanthamoeba are single-celled organisms ranging from 15 to 35 µm in length, with a flexible cell wall that allows them to change shape from round or oval to triangular. There are two stages in the life cycle of Acanthamoeba: the cyst stage and the trophozoite stage which are infectious to animal organisms and can cause skin infections, encephalitis or keratitis.
Damage to the skin provides Acanthamoeba species access to the host's body, where they can either cause local infection or spread through the blood to other organs and the central nervous system. Infection causes an immune response that can damage nerve cells and can be fatal. The cysts can also enter the body by inhalation and after reaching the airways they progress to the next stage in their life cycle. The cyst cell wall disappears, the nucleus divides twice, and the protozoan enters the infectious stage of the trophozoite. Trophozoites reproduce by mitosis and later develop into a new cyst with a glycogen vacuole and an outer cell wall that are capable of infecting new hosts. Infections of the skin and other organs with Acanthamoeba are generally rare and are observed in people with weakened immune systems.
Granulomatous encephalitis can present with symptoms such as headaches, fever, convulsions and a disturbed mental state and can result in coma and death several months after infection.
Ocular infections are seen in people with a fully functioning immune system and most often in people wearing contact lenses. The infection induces keratitis which can cause permanent blindness. Symptoms of the infection include eye pain, blurred vision and light sensitivity. Infection occurs mainly in contact lens users due to the contamination of lenses, cleaning solutions or storage pouches.
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. Correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.