Akantamebiaz - the protozoan damage of eyes, integuments and TsNS caused by free living amoebas. The disease proceeds in the form of akantamebny conjunctivitis and a keratit, dermatitis or granulematozny encephalitis. Perforation of a cornea, formation of abscesses of internals can serve as complications of an akantamebiaz. The diagnosis of an akantamebiaz is established by detection of amoebas and their tsist in plaintive liquid, scrapes from a cornea, bioptata of skin, cerebrospinal fluid. Local and system treatment of an akantamebiaz is carried out by antibiotics of group of aminoglycosides (in the form of eye drops, ointments, injections).
Akantamebiaz – , caused by pathogenic amoebas of the sort Acanthamoeba. In most cases proceeds in the form of an akantamyobny keratit and akantamebny damage of skin. Sporadic cases of akantamebny dermatitis are registered in the countries with subtropical and tropical climate more often. Akantamebny keratit usually arises at the people using contact correction of sight. Akantamebny granulematozny encephalitis is less often diagnosed. In the world about 400 cases of the akantamebiaz proceeding with defeat of TsNS are registered; survival at this form makes only 2-3%. Thus, is the urgent cross-disciplinary problem solved by experts in the field of ophthalmology, dermatology and neurology.
Reasons of an akantamebiaz
Among free living pathogenic amoebas of the sort Acanthamoeba danger to the person is constituted by 6 types: A. hatchetti (cause damage of eyes), A. palestinensis and A. astronyxis (cause damage to TsNS), A. polyphaga, A. Culbertsoni, A. castellanii (cause various damages, including skin). In the course of life cycle of an amoeba of the sort Acanthamoeba pass a vegetative stage (trofozoit) also a stage tsist.
Akantameba - the aerobic organisms living in the soil, still fresh-water water of the natural and artificial reservoirs which are especially polluted by dumpings of sewage. Besides, monocelled protozoa safely live in tap water, the sewerage, water from heating pipes. Increase in population is promoted by the water temperature above 28 °C and presence at it of various organic substances. In case of decrease in surrounding temperature or drying of a reservoir of an akantameba intsistirutsya. The being able tsist parasites well transfer fluctuations of temperature and , influence of anti-septic tanks and disinfectants.
At hit in a human body activators of an akantamebiaz pass into a vegetative state again and become capable to parasitism. As a source of an invasion kontaminirovanny akantamebam the soil and water act. Infection of the person is carried out contact and household, food and water in the ways. Akantamebiaz of eyes usually arises at the patients who are not following hygienic rules of carrying and care of soft contact lenses: not removing them during bathing and the reception of a shower which are neglecting measures of disinfection, not processing a hand before putting on of lenses etc. Quite often are found in healthy people of an akantameba in nasopharyngeal slime and excrements, however, mainly, persons with an immunodeficiency (especially HIV infection), diabetes, malignant new growths, alimentary insufficiency are subject to development of an akantamebiaz of TsNS.
Symptoms of an akantamebiaz
Akantamebiaz most often proceeds in the form of an akantamebny keratit. Initial symptoms of an eye infection include reddening of eyes, the cutting eye pain, a photophobia, dacryagogue, a sight zatumanennost, feeling of a foreign matter in an eye. In the late period there is noticeable a ring-shaped or diskovidny turbidity of a cornea. Alternation of aggravations and remissions at an akantamebiaza of eyes quite often leads to a uveit, a sklerit, an iridotsiklit, formation of a hypopeony. Without adequate therapy to an akantamebiaza quickly progresses, causing perforation of a cornea.
Akantamebiaz of skin can arise initially (independently) or again, owing to initial damage of the central nervous system. Primary akantamebny damage of skin happens at hit of the water polluted by tsist of amoebas on open wounds of an integument. At the same time on face skin, a breast, backs, extremities are formed the single or multiple small knots, papules or spots of gray-black color having a diameter of 0,5-3 cm. Further these elements are transformed to the skin ulcers covered with a scab. At a long current formation of akantamebny abscesses of muscles, lymph nodes, a liver, lungs and other internals is possible. Secondary skin it is caused by a dissemination from primary center.
Damage to TsNS at an akantamebiaza is caused by development of granulematozny akantamebny encephalitis. This rare pathology usually arises at a hematogenic drift in a brain from primary centers. Amoebic defeat can affect brain substance, a vascular or web cover, basal gangliya. At normal resistance of an organism the granulematozny inflammation develops; at lowered – necrotic process. The incubatory period at akantamebny damage of a brain lasts from several weeks to one month and more. The initial stage of an akantamebiaz is characterized by a changeable subfebrilitet, drowsiness, headaches, spasms, convergence violations. Progressing of an akantamebiaz of TsNS leads to development of a coma and a lethal outcome.
Diagnostics and treatment of an akantamebiaz
Depending on a form of an akantamebiaz its diagnostics and treatment is carried out by experts ophthalmologists, dermatologists, neurologists. The diagnosis of akantamebny damage of eyes, skin, a brain is confirmed by detection of vegetative and tsistny forms in the studied material. At an akantamebny keratit - it is plaintive liquid, washouts and scrapes of a cornea; at akantamebny dermatitis - separated infiltrates, a skin bioptata; at granulematozny encephalitis - cerebrospinal fluid. Except a microscopic research of medicines, the cultural method, serological tests, biological test is applied to verification of the diagnosis of an akantamebiaz. At suspicion on it is necessary to exclude at the patient of a keratita, encephalitis and a dermatosis of other etiology.
Treatment of an akantamebny keratit demands refusal of carrying contact lenses. Local therapy includes hourly instillation in a conjunctival cavity of antibacterial medicines (gentamycin, Neomycinum, a polimiksin In, etc.), corticosteroids; applications of antifungal means (an amfoteritsin In, a ketokonazola). In a combination with eye drops mazevy applications for an eyelid of the same means are used. At the progressing changes of a cornea carrying out a keratoplasty can be shown.
At an akantamebiaza of skin system antibiotic treatment by medicines from group of aminoglycosides, local putting ointments with Neomycinum, polimiksiny, etc. is carried out. The most complex challenge is represented by therapy of akantamebny encephalitis. At this clinical form of an akantamebiaz intravenous administration of an amfoteritsin In, purpose of a combination of a trimetoprim and sulfametoksazol, aminoglycosides is shown. Treatment of an akantamebiaz of TsNS is effective only in isolated cases.
Forecast and prevention of an akantamebiaz
At akantamebny damage of skin and an eye the forecast for life favorable, however a brain in most cases comes to an end letalno. Prevention of an akantamebny keratit consists in observance of rules of use and care of contact lenses, their storage only in special sterile solutions, processing of containers for lenses, periodic instillation in eyes of bactericidal means (a sulfatsil of sodium, etc.), need of extraction of contact lenses for the period of bathing, visit of a bath and a sauna, washing under a shower. TsNS allows to warn skin and observance of rules of personal hygiene, restriction of contact with the polluted reservoirs which are habitats .