Leishmaniasis - Causes, symptoms and treatment. MF.

Leishmaniasis is a group of protozoal diseases of the skin and mucous membranes( including internal organs) with the corresponding specific symptoms depending on the form of leishmaniasis( visceral or cutaneous) caused by protozoans of the genus Leishmania, which are transmitted by mosquitoes of the genus Phlebotomus( Leishmaniasis of the Old World) andLutzomyia( leishmaniasis of the New World).

Leishmaniasis causative agents

Leishmania is an intracellular parasite, at present about 20 species and subspecies of leishmanias are known.

Leishmania under the microscope

They are characterized by a complex life cycle in the body of two hosts, one of which is the vertebral( including humans), and the second is the mosquitoes living in Europe, Africa, Asia and America. It develops intracellularly, in free macrophages and in cells of the CMF( the system of mononuclear phagocytes: connective tissue histiocytes, liver cell Kupfer( stellate reticuloendotheliocytes), alveolar macrophages of the lungs, macrophages of lymph nodes, spleen, bone marrow, pleural and peritoneal macrophages, osteoclasts of bone tissue, microglia of the nervoustissues, synovial synovial membranes, skin cells of Langerhans, unpigmented granular dendritic cells).One cell can detect about 100 or more pathogens. Mosquitoes get infected by swallowing amastigot( an unbuttoned form of existence that lives in the body of vertebrates) with the blood of a sick animal or person. In the intestine of the maskata, amostigoth is transformed into promastigot( flagellate form of existence).

Leishmania cycle

Stability: the causative agent is killed by disinfectants, critical high and low temperatures.

Susceptibility and prevalence: susceptibility is universal, but it is difficult to accurately determine the geographical distribution and frequency of detection, because in many countries this disease is not subject to mandatory registration. It is known that leishmaniasis annually affects not less than 400 thousand people in 80 countries. There are projects for the development of new territories of the Old World and the New World - this is connected with the resettlement of people and as a consequence, emerging epidemics in Iran, Iraq, Israel, the Sudan and other states. The probability of importing an infection into our region is quite high, given that leishmaniasis occurs along the paths of the most active trade and tourist migration of the population.

The wide spread of leishmaniasis, the long incubation period( reaching a period of up to 2 years), the severity of the course and the high incidence of adverse outcomes in untreated cases, the poor awareness of practical doctors all complicate the diagnosis and treatment of leishmaniasis.

The causes of leishmaniasis

The source is a sick person, dogs, wild mammals from the orders of predators and rodents. Transmission routes - transmissible( with bites), blood transfusion. Contact( in the presence of micro-trauma) pathway remains in question, with the exception of infection with visceral forms. The infection reservoir is female mosquitoes.

Symptoms of visceral leishmaniasis

The incubation period varies from a few days to 15 months, and is considered from the moment of penetration of the pathogen to the first clinical symptoms. The period of clinical manifestations begins gradually( but perhaps an acute beginning), in the form of unmotivated increased fatigue, weakness, feelings of heaviness and discomfort in the abdomen, loss of appetite, weight loss, the patient drew attention mainly to the fact that he "somehow"The stomach begins to increase. Periodically, the temperature rises first to subfebrile digits, and then to higher ones. At the initial examination, the doctor may notice:

• pallor of the skin with the subsequent occurrence of hemorrhages on the skin and mucous membranes, as well as the appearance of skin and mucous membranes. Sometimes the primary affect is revealed - small in size, with lentils, a tight pale pink nodule or sore, in the scrapes of which a large number of leishmanias are found.

• Increased regional lymph nodes can rarely be detected, because they are enlarged slightly, painless and the skin over them is not changed.

• With auscultation - muffled heart tones, systolic murmur over the tip, mild tachycardia.

• Detect hepatosplenomegaly( enlargement of the liver and spleen), but with palpation pain is not noted. In the long term, this can lead to inhibition of the functional activity of these organs, and this will be reflected in the violation of the immune response, the disorganization of the coagulating and anticoagulant systems, enzymatic deficiency, etc. - all these emerging factors give visible symptoms of leishmaniasis( icterism, hemorrhages, pallor due to anemia).

• Fever reaches high numbers, but its dynamics can not be predicted.

• At the height of the disease, the skin becomes dry, scaly, and dull brittle hair falls easily, forming small nests of baldness.

• Kidney damage is of an immunocomplex character, with the further development of glomerulonephritis.

There are also atypical forms of visceral leishmaniasis : lymphatic leishmaniasis with generalized lymphadenopathy, leishmaniasis with a predominance of hemorrhagic eruptions, leishmania with predominantly mucous membranes. The visceral form of leishmaniasis has some differences in different regions of the globe, so on this principle they are distinguished: children's feces-azar, Indian kala-azar, African, American.

Antropanous cutaneous leishmaniasis of the Old World( late ulcer form, "yearlong," Ashgabat ")

Places of possible infection: Africa, southern Europe, the Middle East, Central Asia, India, Pakestan. The infection occurs by transmis- sion by a mosquito bite, at the site of the bite the primary element is formed - the papule, which increases in size, then becomes crusted, then ulcerated and later covered with granulations( these are the primary signs of healing).From the moment of the bite to the first manifestations, it can take 3-15 months, and for each stage of the formation of the inflammatory process( from papules to granulations) takes an average of 3-6 months, but by 12 months these ulcers heal. The localization of ulcers is mainly on the face and limbs, and there may be 1-10 of them. After the transferred disease, a stable lifelong immunity is formed.

Skin form of leishmaniasis

Zoanthroponous dermal Leishmaniasis of the Old World( early leishmaniasis)

Places of possible infection: South and Central Asia, sometimes Africa. The entire path of infection occurs almost 3 times faster: the incubation period is 7-45 days, the inflammatory infiltrate appears after 1-2 weeks, around it there are child eruptions, but everything passes in 6 months, and it also ends up scarring. Immunity for life.

Skin-mucous leishmaniasis of the New World( espuda): Mexican, Brazilian, Peruvian

This is a natural focal form. The transports are the masks. From the bite to the first clinical manifestations, it takes from 2 weeks to 3 months. At the site of the bite, deep ulcers are formed, involving mucous, lymph nodes and vessels - this is followed by severe cosmetic complications and a serious prognosis.

Skin and mucous form of leishmaniasis( espuda)

Diagnosis of leishmaniasis

Serological reactions may cause diagnostic errors, since leishmanias have common antigens with mycobacteria and trypanosomes.

In case of diagnosis, the fence of the material depends on the form of the disease: for example, when scabies are examined, scraping, visceral forms - blood, bone marrow punctures, liver biopsy, lymph nodes, scrapings from the nasal mucosa. In the investigated material, colored according to Romanovsky-Giemsa, intracellularly located astigots are found. In case of epidemiological research, skin allergological tests are used, the positive result of which indicates the presence in the past of contact with leishmania - the Montenegro trial.

Treatment of leishmaniasis

Antibiotics: monomycin, solusurumin, acrichine, aminoquinol, pentamidine isothionate. Symptomatic therapy of dominant conditions. Also effective is local treatment, ie, cheating with the above drugs or using lotions. Because for our latitudes this disease is not typical, we have to refer more to the experience of foreign authors who have experience in the treatment of leishmaniasis, namely, not a few of them refer to the choice of monomycin and aminoquinol as the most effective drugs against this pathogen. If these drugs are ineffective, 5-valent antimony is used, if this drug does not help, then pentamidine isothionate is used - but this step scheme is more suitable for visceral form. Laser therapy is effective, especially at the stage of the tubercle. The average duration of treatment is 2 weeks. As you can see, drugs are specific and there can not be any self-medication and self-diagnosis.

Complications of leishmaniasis and prognosis

Depending on the form and choice of treatment tactics, namely how early it is started. So, for example, with the dermal form in place of leishmania, there remains hyper / depigmentation, small scars or, with early diagnosis and treatment, everything can pass without a trace. The most dangerous in the prognostic plan is the dermal-mucous form, because it leaves after itself disabling cosmetic scars on the site of ulceration and increases the risk of secondary bacterial and septic complications.

The prognosis for timely treatment is quite favorable, the lethality is very low and the cause is secondary complications.

Prevention of leishmaniasis

Specific prevention - the introduction of live cultural vaccine no later than 3 months before going to the epidemic area. Nonspecific prevention is the fight against mosquitoes.

Therapist doctor Shabanova I.Е.