What is Cutaneous Leishmaniasis?
Cutaneous leishmaniasis is a disease endemic to regions where air temperature is not lower than 20 ° C for 50 days, but isolated cases occur as excusive in any region of the country. Synonyms of cutaneous leishmaniasis are: Old World leishmaniasis, Pendinsky ulcer, Ashkhabad, godovik, desert-rural leishmaniasis, etc. It is found in Central Asia (Turkmenistan, Uzbekistan), Afghanistan.
Causes of Cutaneous Leishmaniasis
Cutaneous leishmaniasis is caused by a pathogen of the genus protozoa, having several varieties. The common name of the pathogen Leischmania tropica, since it was first discovered by Leishman (1872), and in 1898, was described by the Russian scientist P.F. Borovsky. The causative agent of leishmaniasis Leischmania tropica belongs to the simplest (Protozoa). To detect it, the tubercle or regional infiltration of Leishmaniomas is squeezed with two fingers for anemization, and a small and shallow skin incision is made with a scalpel. From the edges of the incision, the tissue pieces and tissue fluid are scraped off with a scalpel. From the resulting material is prepared smear, painted by Romanovsky-Giemsa. The causative agent (Borovsky’s calf) is an ovoid, ovate formation 2-5 µm long, 1.5 to 4 µm wide, in the protoplasm of which two cores are found — a large oval and an additional rod-shaped (blepharoblast). In smears, the protoplasm of Leishmania is painted in a light blue color, the large nucleus is red or red-violet, the additional core is dark violet. The parasite is found in large numbers in macrophages and free groups in the blood flow, as well as in the lesions of the skin.
The presence of two clinical types of the disease has been established: acutely necrotic (rural, or zoonotic, type) and late-ulcerating (urban anthroponotic type). The causative agent of the first species is Leischmania tropica major, the second is Leischmania tropica minor. Both pathogens differ in their biological characteristics and the epidemiology of the process. So, L. Tropica major, which causes the acutely necrotic (rural) type of disease, lives and parasitizes rodents in sandy fields (ground squirrels, gerbils, hedgehogs, rats), as well as dogs. The vectors are mosquitoes of the genus Phlebotomus. L. tropica minor parasitizes only on humans, but the carriers are the same mosquitoes of the genus Phlebotomus.
For the rural type is characterized by seasonality associated with the presence of mosquitoes in the warm season. The incidence begins to be noted in the spring, increases in the summer and decreases by the winter. The urban type is characterized by a lack of seasonality and a long course. It can show up at any time of the year. It was found out (P.V. Kozhevnikov, N.F. Rodyakin) that animal carriage is often possible in animals and humans without marked clinical manifestations, which complicates epidemiological and prophylactic aspects of health measures.
Symptoms of Cutaneous Leishmaniasis
For the rural (zoonotic) type, a relatively short incubation period (from 1–2 to 3–5 weeks) and a not very long (3–6 months) course are characteristic. Usually in open areas of the skin appear conical tubercles with a broad base, red-bluish color with brownish or yellowish tinge, testovaty consistency. Subsequently, the hillocks increase in size and after 1-3 months. open with the formation of round or irregular-shaped ulcers with an uneven bottom and abundant sero-purulent exudate, shrinking into dense layered crusts. The edges of the ulcer are as if eaten away. In the circle, a testovat infiltrate of a pinkish-bluish color is formed, behind which weights of inflamed lymphatic vessels and the so-called rosary of secondary leishmania can be felt. Children have a more acute course with furunculoid, fluctuating pustular nidus formation, rapidly abstaining and necrotizing. Often in adults and children the process is complicated by purulent infection with the development of cellulitis, erysipelas. The inflammatory process ends in 3-8 months. with the formation of scar and stable immunity to this tinn pathogen.
The urban (anthroponotic) type is found in cities and large population centers. It is characterized by a lengthening of the incubation period (on average, 5–8 months, and sometimes 1–2 years) and a slow course of the process, hence the name — yearling. The disease is transmitted from a sick person or carrier through a mosquito carrier. On the open areas of the skin, small tubercles of pinkish or reddish-brown color with a yellowish tinge appear. Elements of a rounded shape, testovaty consistency. Infiltrate unsharply expressed, splits late. Surface ulcers with uneven roller-like edges and a granulating bottom covered with a grayish-yellow serous-purulent discharge. A border of inflammatory infiltration is usually formed in the circumference of ulcers. As in the zoonotic form, nodular lymphangitis (“rosary”) can form along the periphery. They sometimes ulcerate, turning into small, secondary (daughter) leishmaniomas.
The anthroponotic form is a rare clinical form of skin leishmaniasis – lupoid or tuberculoid cutaneous leishmaniosis (metascale). This form is difficult to distinguish from lupus erythematosus due to the appearance of bumps on scars formed after regression by the Leishmania or along the periphery. Hillocks are flat, barely towering above the skin, brownish in color, soft consistency, giving a clear brownish color during the diascopy (symptom of apple jelly). The number of hillocks can gradually increase, persist for a long time, and can hardly be treated. Tuberculoid leishmaniasis is most often localized on the skin of the face and is observed in children and adolescents. The development of this form of leishmaniasis is associated with the inadequacy of immunity due to the presence of a chronic infection, hypothermia, trauma, or possible natural superinfection.
The atypical form of the anthroponotic type includes mucocutaneous and diffuse cutaneous leishmaniasis. Characteristic of these varieties is the slow formation of the process. Ulcerations develop late or are absent. Healing occurs within 1-3 years or even longer. The primary elements of the skin-mucous leishmaniasis are similar to the usual type of tubercle with subsequent ulceration. Metastatic spread of the process to the mucous membrane of the mouth, nose and pharynx occurs at an early stage of the disease, but sometimes it may occur several years later. Eroding and ulceration of the tubercles is accompanied by the destruction of soft tissues, cartilage of the oral cavity and nasopharynx. At the same time, swelling of the nasal mucosa, the red border of the lips, develops. Often joins a secondary infection. The process ends with pronounced mutilations.
Diffuse cutaneous leishmaniasis is manifested by the common elements of multiple hillocks on the face and on the open parts of the extremities. Merging, rashes resemble lesions in leprosy. Characterized by the absence of ulcerations and lesions of the mucous membranes. The disease does not spontaneously pass and is prone to relapse after treatment.
Diagnosis of Cutaneous Leishmaniasis
Diagnosis of cutaneous leishmaniasis is based on peculiar efflorescences of a nodular or bumpy type, with the presence of distinct nodular lymphangitis along the periphery of the primary foci. Anamnestic data on the stay of patients in endemic places helps to establish the diagnosis. Differential diagnosis is carried out with lupus tuberculosis, secondary and tertiary syphilides, chronic ulcer pyoderma, malignant neoplasms, sarcoidosis. The main rationale for the diagnosis is the patient’s stay in the endemic zone and the detection of a pathogen L. Tropica (Borovsky body) in the scraping from the edges of the pathogen, which is localized in large numbers, mainly in macrophages. The skin test with leishmanin is used for the diagnosis (Montenofo test).
Treatment of Cutaneous Leishmaniasis
Monomitsin, solysurmin, glucantim, metacycline, doxycycline, antimalarial drugs are shown.
Monomitsin – 250,000 IU intramuscularly 3 times a day every 8 hours, for a course of 7,000,000 9,000,000 IU, glucantim (60 mg / kg intramuscularly No. 15), sechnidazole (500 mg 4 times a day) can also be used for 3 weeks, then 2 times a day for another 3 weeks), as well as solyusurmin, metacycline, doxycycline, anti-malarial drugs (including for the treatment of unopened leishmania); cryodestruction, laser therapy. 2 3% monomitsinovaya ointment.
Prevention of Cutaneous Leishmaniasis
Carrying out a complex of deratization works in places of natural foci. Of great importance is the timely detection and treatment of patients, the use of individual means of protection against mosquitoes. In the autumn-winter period, prophylactic vaccinations are carried out by intradermal administration of 0.1-0.2 ml of a liquid medium containing a live culture of the rural-type Leishmaniasis pathogen (L. Tropica major), which causes the rapid development of Leishmania, providing immunity to both types of Leishmaniasis. The resulting inoculation leishmanioma proceeds without ulceration with rapid disappearance, leaving a barely noticeable atrophic scar.
For the destruction of rodents, they seed their holes in a zone wide, up to 15 km from the village. The seed zone is dictated by the range of mosquitoes. Places of breeding mosquitoes (in particular, accumulations of garbage) are treated with bleach, residential and utility rooms – by spraying insecticide preparations (thiophos, hexachlorane). Disinfection of residential buildings and outbuildings is shown.
Considering that mosquitoes attack people mostly at night, in endemic places of leishmaniasis, bed curtains are made of netting or gauze, which are smeared with Lysol or turpentine, which repel mosquitoes. During the daytime, the skin (mostly of the exposed parts of the body) is smeared with a special cream, clove oil; You can also use strong-smelling cologne, or dimethyl phthalate, which protects you from mosquito bites for several hours.