Buruli's ulcer – the infectious dermatological disease caused by defeat of integuments one of types of mikobakteriya. It is generally widespread in the tropical tropical countries with a humid climate. Symptoms of this state are the ulcers with necrotic contents at the bottom arising mainly on skin of razgibatelny surfaces of knee and elbow joints. Diagnosis of an ulcer of Buruli is performed by means of dermatological survey, studying of the anamnesis of the sick, bacteriological research separated from the ulcer centers. Therapy of a disease is made by antibiotics, however their efficiency can be insufficient for full recovery. Also use local treatment by solutions of anti-septic tanks, in hard cases surgical removal of the pathological centers is shown.
Buruli's ulcer – the endemic dermatological disease, the skin relating to group of mikobakterioz which was earlier observed only in certain regions of Africa, but now extended more than in 25 countries. The first descriptions of ulcers, characteristic of this pathology, are dated still 1898, but its more serious studying began only in 1948 when the Australian doctor P. Mac-Kallem managed to allocate and cultivate the causative agent of a disease. Buruli's ulcer received the name in the sixties when in the region of Uganda of the same name there was real epidemic of this dermatological state. Today this disease meets in a number of the countries of the Equatorial Africa, there are data on the outbreaks of pathology in Southeast Asia and Australia, separate cases are described in China. Spread of an ulcer of Buruli is promoted by a warm and humid climate and a large number of reservoirs with stagnant water in the region. Infection occurs in the contact way, mikobakteriya can be transmitted from the person to the person through touches, use of the general objects, and also at contact with the infected water or the soil.
Reasons of an ulcer of Buruli
Buruli's ulcer is caused by Mycobacterium ulcerans mikobakteriya, this activator has both similarity, and essential differences to other microorganisms from the group. As well as other kinds of mikobakteriya (for example, causative agents of tuberculosis and leprosy), Mycobacterium ulcerans is an acid resisting microorganism with very slow development. Growth of noticeable colonies at crops on nutrient mediums takes 7-12 weeks. At the same time the causative agent of an ulcer of Buruli is incapable to parasitize in macrophages and other cages as it other mikobakteriya, and unlike them allocates active () which possesses cytolytic action (especially concerning adipocytes – the fatty cages which are available in hypodermic fatty cellulose). There are instructions that the toxin produced by Mycobacterium ulcerans has immunosupressivny properties that facilitates infection and considerably complicates the course of a disease at the multiple ulcer centers.
Tanks of mikobakteriya in the wild nature are not defined today. It is supposed that it can be water from stagnant reservoirs, water plants and some animals – in particular, the causative agent of an ulcer of Buruli was found on hair of koalas and kangaroo in Australia. This uncertainty complicates to epidemiologists development of prevention and antiepidemiological actions in endemic regions. Also explosive growth of incidence of Buruli's ulcer in the second half of the 20th century when this pathology from several small centers in Africa extended to the huge territory from Uganda to Australia is inexplicable at the moment – it is considered that it turned out to be consequence of strengthening of migration flows and commodity turnover between the countries.
Infection with the causative agent of an ulcer of Buruli occurs through "entrance gate" – on skin grazes, cuts, stings of insects and other damages can be those. The deep injuries reaching hypodermic fatty cellulose as Mycobacterium ulcerans has affinity to fabrics rich with lipids are especially dangerous. Long-term studying of an ulcer of Buruli elicited the fact that development of this disease requires often existence of the previous weakening of an organism because of these or those factors. Can act as those chronic shortage of proteins in a diet (starvation), hypovitaminoses, infection with parasites (helminthoses), wearisome diseases (for example, malaria). It explains why Buruli's ulcer is generally widespread in poor developing countries with the low level of health care and social security of the population.
Symptoms of an ulcer of Buruli
In most cases development of an ulcer of Buruli happens on the place of the previous injury of skin, and – rather deep. At the same time on the place of the beginning to live cut or a graze painless infiltrate, firm to the touch and located in deep layers of skin is formed. Between the moment of infection and development of infiltrate there is an asymptomatic incubatory period duration from several days to 7-10 weeks. Skin over pathological education at Buruli's ulcer at first becomes hyper pigmented, then cyanotic because of venous stagnation. No subjective or general symptoms at this stage of a disease are defined.
In 6-15 days after formation of infiltrate its central part is softened, ulcer defeat with dense edges and nekrotizirovanny masses at the bottom is formed. At Buruli's ulcer this masses quickly enough dries up, forming a scab of black color. The extent of ulcer defect can vary from several millimeters to 3-4 centimeters, but the defeat zone also remains painless at a palpation. As a rule, defeat at Buruli's ulcer first single, can sometimes arise several ulcer surfaces separated from each other – it is caused by infection of several sites of skin at once. An important diagnostic symptom of an ulcer of Buruli is lack of any general reactions including regionarny lymphadenitis – lymph nodes are not increased and painless at a palpation.
In the absence of treatment complications of an ulcer of Buruli develop. Most often the secondary bacterial infection, usually purulent character joins. Emergence of the pulsing pain in a skin ulceration zone, the putrefactive smell and availability of pus can be signs of this complication. There is lymphadenitis, temperature increase is possible. In the absence of such complication of an ulcer of Buruli around primary center affiliated elements can be formed – as a rule, they a little smaller size, but also pass all stages of development from infiltrate to an ulcer. The centers of defeat are separated from each other by the strips of the condensed skin called by dermatologists "skin bridges". In hard cases of an ulcer of Buruli the combination of a secondary infection and multiple defeats can threaten life of the patient and to become a reason for amputation of an extremity.
Diagnosis of an ulcer of Buruli
Diagnosis of an ulcer of Buruli is based on studying of the anamnesis and results of inquiry of the patient, survey by the expert in the sphere of dermatology, a microscopic and bacteriological research separated from skin erosion. Dermatological survey reveals painless infiltrates (at initial stages of a disease) or the ulcers covered with the dried-up black scab, primary localization – hands (brushes, forearms) and legs. Always (except for accession of a secondary infection) there is no reaction from regionarny lymph nodes. At inquiry sick Buruli's ulcer in most cases clear that development of a disease was preceded by a noticeable or deep trauma of integuments. Quite often in the same way it is possible to find also a source of infection – presence of similar pathology at the family or acquaintances, development of symptoms after bathing in a stagnant fresh-water reservoir and so forth.
For carrying out a microscopic research at Buruli's ulcer material is tried to be taken from edge of the center – it forms a niche where there is an accumulation of the become lifeless skin tissues. The most informative method of diagnostics is coloring of dabs according to Tsilyu-Nielsen – at this Mycobacterium ulcerans are painted in red color. Mikobakteriya which are causative agents of an ulcer of Buruli, as a rule, settle down in dab one by one, in pairs or in the form of long chains. Crops are model on nutrient medium (Levenshteyna-Janszen) and its storage at a temperature of 30-32 degrees in 7-12 weeks lead to emergence of small colonies of rozovatovy color. Differentiation of causative agents of an ulcer of Buruli from other mikobakteriya is made on inability of Mycobacterium ulcerans to splitting of urea and hydrogen peroxide and traditional antitubercular medicines resistance – to paraaminosalicylic acid (PASK), an isoniazid. In recent years for definition of this disease began to use technology of polymerase chain reaction that allows to reveal activator DNA – such method is considered the most exact.
Treatment of an ulcer of Buruli
Therapy of an ulcer of Buruli rather difficult because of a weak susceptibility of the activator to the majority of antibacterial means. Medicine of the first line in treatment of this disease is the antibiotic rifampicin, however its efficiency strongly differs in different cases – from bystry and long effect to almost full immunity of mikobakteriya. Antibiotics from other groups have a smaller efficiency at Buruli's ulcer. An important role in therapy of this state is played by increase in resilience of an organism to infections – it is reached by purpose of immunostimulators, vitamin medicines, good nutrition of the patient.
Local treatment of an ulcer of Buruli it can be made only in combination with system antibacterial therapy. Compresses from solutions of various anti-septic tanks are used (for example, a hlorgeksidina), the quite good effect is reached by imposing of bandages with hypertensive solution – it has the good clearing effect. The above-stated actions not only facilitate a condition of the patient, but also are active prevention of such complication of an ulcer of Buruli as a secondary infection. In some cases at a long absence of effect of conservative therapy or crushing multiple damages of skin surgical treatment is recommended. It is made by excision of the sites affected with Buruli's ulcer, removals of infiltrates and the subsequent ushivaniye of wounds or closing of defects by skin plasticity.
Forecast and prevention of an ulcer of Buruli
The forecast of an ulcer of Buruli, as a rule, uncertain as expressiveness of symptoms of pathology depends on a set of factors – sizes of "entrance gate", the resilience of an organism of an infection, age of the patient and so forth. At in due time begun treatment rather bystry healing of an ulcer with formation of a hem sometimes is observed, but in most cases ulcerations of skin remain for many weeks. In especially hard cases (at multiple defeat by Buruli's ulcer and accession of a secondary infection) development of toxic shock, gangrene of extremities, sepsis is possible that threatens the patient's life. Methods of prevention of this disease are only developed, there were attempts to use vaccine BTsZh in endemic areas. It gave temporary immunity against Buruli's ulcer, however its duration made only 4-6 months. Now WHO continues searches of an effective vaccine, and also studying of Mycobacterium ulcerans for decrease in incidence of this pathology.