Sunday, June 2, 2013

Buruli ulcer

Buruli ulcer
Buruli ulcer - pathological processes of the skin with the formation of ulcers are a common group of diseases in the tropics and subtropics. The mechanisms of their development and clinical manifestations are diverse, which is not an easy task for dermatologists.

Despite the fact that this group of diverse pathologies, all of them can also select a special kind of diseases caused by mycobacteria and are much more prevalent than all other.

What Causes Buruli ulcer:

 The scientific name of the pathogen that causes this pathology, - Mycobacterium ulcerans. The average size of the pathogen range from 2,1 × 0,28 to 2,8 × 0,33 m. If they are painted with special chemical dyes and viewed under a microscope, you can see that these bacteria are arranged singly or in groups, sometimes in the chain, resembling in appearance rosary.

Pathogens oblong shape, and in groups they are always positioned with respect to each other simultaneously. The number of microbial cells in a group can reach 100 or more. Pathogen under no circumstances is not able to form spores and capsules. Bacterial cells have no mobility. They are very stable in the environment and do not die when subjected to a solution of alcohol and alkalis. At candling ultraviolet rays have the ability to emit light. The most well-growing mycobacteria proliferate at ambient temperature 32 - 34 ° C. There is always only in the presence of oxygen, oxygen-free environment rather die quickly. When sowing colonies of pathogens on any medium they grow slowly and with difficulty, that is a significant problem regarding the diagnosis of the disease.

Pathogenesis (what's going on?) During Buruli ulcer: 

 Big enough problem for a disease Buruli is to identify the sources of human infection, since the latter until now have not been found. Are also unknown, and the mechanism of infection, the penetration of pathogenic bacteria in the body. Currently, the most common is the theory that human infection occurs from infected animals, with the participation of blood-sucking insects, which in this case are the carriers of the infection. The disease can affect people at the most different age groups, but most often occurs in children younger. Also still remains an open question as to the immunity to mycobacteria. The mechanisms of its formation and its resistance is not known. The main countries where outbreaks of infection are Uganda, Nigeria, Zaire, Asia, USA, Australia.

The most common bacterial penetration into the body, presumably occurs through damaged skin. It was at this point in the first place developed necrosis of the skin, subcutaneous fat layer, and sometimes some of the other tissues. As a result, the skin appears quite deep and large area ulcer. Around the area of ​​skin necrosis is always evolving area of ​​inflammation. In the bottom and overhangs the ulcer is a significant expansion of the surface layers of the skin, which is a kind of protective and compensatory response.

There are a number of factors that do not directly lead to the development of the disease, but they can significantly contribute to this. These include: lack of power and, therefore, insufficient intake of proteins (the cause of which can also be a diet deficient in proteins), vitamins A and Group B, metabolism in the body, in particular the exchange of water and some important salts, the presence of in the body of chronic hardly proceeding foci of infection and parasitic diseases of origin (parasitic disease, amebiasis, giardiasis, etc.).

Symptoms of Buruli ulcer:

On questioning the patient, he can point to the preceding parts of traumatization of the skin in the exposed areas of the body, which may be due, for example, to the professional activities of the sick. In children, skin injury occurs frequently, which is another factor responsible for the higher incidence of disease in childhood.

In the course of the disease is always a latent period, but its duration is not yet established. At the very beginning of the disease in the place of the introduction of pathogens into the skin of her seal is formed, a few rise above the level of healthy skin and has a slightly more intense color due to excess deposition of skin pigment melanin.

When the feeling of this seal any symptoms often not observed. The general condition of the patient is not suffering: his state of health is satisfactory, the body temperature - normal, which is not typical for bacterial diseases and is a particular feature of the disease. Ulcer formed only after several days from onset. Its contours sufficiently clear, irregularly shaped.

When probing the edge of the ulcer are much sealed. In the area of ​​the bottom and the edges of the ulcer there is a large amount of mass, which are the remains of the dead skin and subcutaneous fat. In the future, they wither, and at this point formed a scab black. In the course of the disease can join and the other (usually pus) infection. In this case, the bottom of the lesions develop abundant growths which become putrid smell.

Ulcers on the skin of the patient are always placed in isolation. Over time around such a "parent" ulcers may appear "daughter", which have smaller dimensions. Lots of skin, separating these structures originally emerged from ulcers, are very thin, they are sealed and much of dermatologists are called skin bridges. In some places the most frequent location is the skin lesions of the extensor surfaces of the forearms-tion and legs. An important difference from other ulcer disease similar in presentation of diseases is that it does not completely revealed no pathological changes in the subcutaneous lymph nodes: they are not at increased, and when there is no probing of pain.

 Diagnosis of Buruli ulcer:

Diagnosis is based on a detailed survey of the patient, during which time it turns onset obtained before trauma to the skin, as well as during its overhaul. The main diagnostically important feature is the appearance on the skin characteristic ulcers. The diagnosis is finally confirmed after the capture of the material in the patient and the detection of pathogens in it with microscopic and bacteriological studies.

The main places of accumulation of pus are mycobacteria, the mass of dead skin, sometimes niches that are formed due to overhang the edges of the sores on her bottom. Pick up the material for the study recommended a soft cotton swab, and specially designed for this solid devices.

The most reliable and valuable for correct diagnosis is the study of material taken from the ulcer base, as far as possible. The basic methods are the direct examination smears under a microscope, and their crop on a special nutrient medium to obtain colonies of pathogens.

Treatment of Buruli ulcer:

Currently no pharmacological agents that allow a wholly successfully cure the disease does not exist. Antibiotics that are currently used, can in some cases lead to a cure, but it is not always observed. The treatment with these drugs on average from 1 to 12 weeks. Antibacterials used in different groups, they all possess varying degrees of effectiveness, but 100% - no known. At present, in this respect active research and development of new, more effective drugs.

Among other activities important place should be allocated to local treatment of cutaneous lesions, which is a daily treatment of ulcers with a weak solution of salt. The purpose of this procedure - moisturizing the skin. Allows you to get a good effect on the area of ​​application of lotions ulcers with an antiseptic solution, it helps them much faster and more effective cleaning. In more rare cases a necessary measure is a surgical procedure in which all the excised ulcer defects, such as parent and child. It is necessary to resort to this method primarily in severe cases.

Weather. Disease different patients can take place in various ways. More often than not, a rather slow healing of ulcers, which occur within 6-9 months. A very interesting feature is that the ulcer heals always only the one end, while the other continues skin necrosis and decay of dead weight. Some patients in the future may quickly complete healing to occur, during which in ulcer area, a large number of growths - the so-called granulation. It only happens once no longer formed a scab. In other situations, the process of constantly progressing, eventually available on the skin sores significantly expand, there are more children. All this leads to extensive and severe skin lesions. Often the disease process extends to the joints, eventually breaking their mobility in part or in full. In a number of cases on the skin of the patient can be placed only a small sore that has existed for many years without increasing in size without forming subsidiaries and not bothering the patient.

Buruli ulcer prophylaxis:

Prevention of ulcer disease is a big problem, because at the moment not fully understood the reasons for its occurrence, mechanism of infection and pathogens entering the body of the sick. On the properties and origin of disease pathogen itself is very close to the mycobacteria that cause tuberculosis. So many times there were attempts to carry out prevention and the development of immunity by the introduction of the BCG vaccine that is used as a preventive measure in tuberculosis. In particular, such measures Uganda gave good results. Later, however, it became clear that the immunity produced by this is quite unstable, and after a short time again there is a risk of infection. The period of immunity to mycobacteria on the average of 6 months or less.

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