Buruli ulcer is a chronic, contagious tropical disease caused by the bacteria Mycobacterium ulcerans. It is an endemic disease, that is, it is found among the population living in a specific area. The disease affects the skin, subcutaneous tissue, muscles and bones, and can cause severe, often lifelong disability.

Buruli ulcerationis a tropical and subtropical climate disease that occurs mainly in Africa, Southeast Asia, South America and Australia. After tuberculosis and leprosy, it is the third most common mycobacteriosis in the world, so it can be seen that this problem is not uncommon. Moreover, in 2015 WHO recorded several thousand cases in over a dozen new countries, but nevertheless, it was announced that the total number of cases had decreased in recent years. It should be mentioned that Burula ulcer in most cases is diagnosed in children under the age of 15. However, no gender predisposition to developing the disease was revealed.

Buruli's ulcer: causes

Mycobacterium ulceranscauses infection by a hitherto unknown mechanism. There are reports that the disease occurs as a result of superinfection of skin wounds. Some people believe that bacteria can be spread by bed bugs to animals. However, these are only hypotheses, as research is ongoing to explain the detailed pathogenesis.

Burula ulceration - symptoms and clinical course

The course of the disease may differ for each of the endemic areas, but the clinical picture of the Burula ulcer has several distinctive features that can be seen in each of them. The disease initially manifests as a painless lump, plaque or induration appearing on the extremities (slightly more often on the lower limbs than on the upper limbs), sliding against the skin and possibly with a slight swelling. Over time, the lesion becomes deeper and deeper ulceration, which gradually causes necrosis of the skin, subcutaneous tissue and soft tissues. The ulcer is bounded by a flat, raised edge.

According to WHO, Burula's ulcer has been divided into 3 categories. We talk about the first when only a small change is visible on the skin, which does not damage the coating. If not treated properly from the beginning, it takes about 4 weeksthe second stage develops, which includes ulcerated and non-ulcerated nodules, which may be accompanied by swelling. The third and most dangerous category includes inflammation of the bones, muscles, joints and all destructive changes within them.

In over 70% of cases, the disease is diagnosed at the stage of ulceration.

Wounds take many months to heal, and the process often involves the formation of keloids. Most often, the disease has permanent consequences in the form of muscle contractures, deformation of joints or even entire limbs. It would seem that such serious tissue destruction causes the organism's systemic response. However, the bacteria responsible for its formation produces a substance called a mycolactone. This toxin causes local immunosuppression, which means that the cells that are to protect the human body against pathogens are inactivated, and therefore cannot participate in the processes responsible for the formation of pain or fever.

How to recognize a Burula ulcer?

In the vast majority of cases, an experienced physician in an endemic area is able to diagnose a Burula ulcer on the basis of the clinical picture. There are four laboratory methods available to diagnose the disease. The most frequently used test is the PCR test, which enables the detection of bacterial DNA in the test sample. In addition, Burula ulceration can be identified by cell culture, histopathological examination, or direct analysis of biological material under a microscope. Currently, work is underway to introduce a modern method helpful in the diagnosis of the disease. It is to rely on tests detecting the aforementioned mycolactone in the material taken from the patient. This examination is more sensitive than microscopic examination, and due to its simplicity, it could be widely used in areas where more complicated diagnostics is not available.

Buruli ulcer: what should it be differentiated from?

Depending on the patient's age, the extent of the lesion, latitude and accompanying ailments, it is necessary to gradually exclude various disease entities that may resemble Burula's ulceration. Initial nodular lesions may resemble, but are not limited to, a boil, lipoma, fungal lesions, or other skin or subcutaneous infections.

In Australia, papillary lesions may indicate bites by various insects typical of the area.

The swelling that appears in a Burula ulcer may resemble cellulitis, a bacterial infection of the skin and subcutaneous tissue in which- in contrast to the discussed disease - the patient complains of pain and high fever.

In older patients with a history of leg ulceration, lower limb ulceration should be differentiated from, inter alia, changes in the course of chronic venous insufficiency or, for example, with ischemic changes caused by atherosclerosis or diabetes.

In tropical climates, one should remember about skin lesions appearing in the course of cutaneous leishmaniasis, onchocercosis or soft ulcer caused byHaemophilus ducreyi .

Correctly collected medical history plays a very important role in the diagnosis of Burula ulcers. Even if we are in an area that is not endemic to this disease entity, we must remember that nowadays many people decide to travel to the most distant corners of the world, where it is possible to "catch" many diseases that are not found in our homeland.

Burula's ulcer: treatment and prognosis

In the treatment of Buruli ulcer, the most important role is to diagnose the disease as soon as possible and implement appropriate therapy. The disease progresses gradually, and you should do everything you can to avoid its most serious complications that can lead to permanent disability.

Current recommendations are based on eight weeks of combined antibiotic therapy with rifampicin and streptomycin. This treatment should precede any surgical treatment. The duration of treatment and the type of antibiotic are the same for all patients, regardless of the stage of their disease. Only for pregnant women it is recommended to replace streptomycin with clarithromycin.

Surgical treatment is sometimes necessary, which mainly involves removing dead tissue and healing all wounds. Some patients sometimes require appropriate rehabilitation, which is unfortunately impossible in some parts of the world.

Disease, apart from the fact that it can sometimes lead to permanent damage to the body, is rarely life threatening. In HIV-infected patients, Burula ulcers may be more aggressive and the treatment effect may not be as satisfactory as in immunocompetent individuals.

Worth knowing

Is there any prophylaxis against Burula ulceration?Until the precise route of transmission of bacteria that causes Burula ulceration is known, it is impossible to implement appropriate prophylaxis. There are reports that the BCG vaccine gives short-term immunity to pathogenic mycobacteria, but the routine use of this vaccination has not been proven to be effective inprevention of Buruli ulcers. The only way is to actively observe and educate the inhabitants of areas endemic forMycobacterium ulcerans , as well as to quickly diagnose and verify all suspicious changes appearing on the skin.

Category:

Infectious diseases