Pinta is an infectious bacterial disease with a predominant lesion of the skin and mucous membranes. Pathognomonic symptoms are the stages of skin lesions from pinto chancre to vitiligination of the site of penetration of the pathogen. Lymphadenitis, lymphangitis, fever are characteristic. The diagnosis of pinta is based on the data of the bacterioscopic method of examination of chancre and rash, negative results of screening analysis for syphilis. Treatment includes etiotropic drugs (antibiotics) and symptomatic agents (antipyretic, desensitizing).
A67 Pinta [Karate]
Pinta is a treponematosis endemic to Latin America. The first written mention of the disease dates back to the XVI century, were left by the Aztecs and Spanish conquistadors. In the last century, it was believed that pinta was caused by a fungus, only in 1927 the Spanish scientist Harreyon isolated spirochetes, which differed in their morphological properties from the pathogens of syphilis. The regions of greatest prevalence are Mexico, Brazil, Venezuela, Bolivia, Peru, Ecuador and Honduras, cases of pinta registration have been reported in Asia and Africa. The disease does not have a clear seasonality and gender characteristics.
The causative agent of treponematosis is the spirochete bacterium Treponema carateum herrejoni. The microorganism lives on the surface of fruits, vegetables and plants, in the soil. Transmission of infection is possible through contact with an infected person and with skin injuries. The transmissible mechanism of infection has been proven – with the bites of bedbugs, mosquitoes and midges. The sexual route of pinta transmission is described, but has no significant significance for the spread of the disease. Risk groups for the disease are children, adolescents, agricultural workers, residents of tropical zones and slums. Risk factors are considered to be a decrease in immunity, hyperhidrosis, a change in the pH of the skin towards an alkaline reaction. Studies of treponematoses have shown that due to the similarity of the pathogens of pinta and syphilis in people with HIV infection, a generalized course of pinta and brain damage is possible, a combination of two treponemal infections is often found.
After penetration through the damaged skin and mucous membranes, the spirochetes begin to actively multiply at the site of introduction. The inflammatory focus is formed from neutrophils, lymphocytes and plasma cells, waste products and decay of bacteria. The elements of the rash (pintids) may differ pathohistologically: psoriasis-like rashes are characterized by parakeratosis, acanthosis; late lesions combine hypochromic foci due to atrophy and lack of melanin in the epidermis and hyperchromic, characterized by excessive accumulation of melanophages in the dermis. Also, numerous lymphocytic perivascular infiltrates are characteristic of the late stages of the disease.
The incubation period of an infectious disease is 6-8 weeks. In the zone of introduction of bacteria into the body, a pinto-like chancre is formed, similar to a tubercle, pain and burning are subjectively felt. Numerous daughter (smaller) chancres form around the primary affect, which look like spots and nodes prone to fusion. The skin is usually hyperemic. After 3-6 weeks, a pink spot with pronounced peeling appears on the site of the chancre. Usually the chancres are located on open areas of the skin – wrists, elbows and ankles, contain a lot of treponemes.
The secondary period of the pinta occurs six months or more from the moment of infection. At first, the disappearance of the primary affect and the appearance of pintides – a secondary widespread rash is noted. Pintids are highly contagious, since spirochetes are located inside them. Externally, the rash looks like polymorphic with a combination of spots, bumps and bubbles forming extensive draining wet areas on the skin. Due to severe itching, patients comb the affected areas, which increases the likelihood of complications. Fever, enlargement of lymph nodes, inflammation of lymphatic vessels is possible.
Especially often the skin and mucous membranes of the genitals, the perianal area are affected. Over time, the spots become less pronounced, skin areas with elements turn pale. Slight itching persists. The skin on the body and nails are thinning, in the area of the soles and palms, on the contrary, there are areas of thickening, excessive keratinization, cracks. The latent period of the pinta lasts three or more years, after which the tertiary stage of the disease occurs. Again, there is an increase in itching and pronounced peeling of the skin. There is a paling of spots on the affected areas up to the formation of extensive areas of vitiligo.
The most common complications of pinta are the consequences of skin and mucous lesions: hair loss and graying, focal atrophy, hyperkeratosis (thickening and coarsening of the skin, the appearance of cracks on the palms and soles). Purulent inflammatory processes often develop – staphylococcal impetigo and streptococcal ectima. Due to prolonged inflammation, especially when the chancre is located on the lower extremities, lymphatic and venous insufficiency, elephantiasis, recurrent erysipelas may form. Cardiovascular complications of pinta are described: aortitis, aortic aneurysm, heart valve lesions.
The diagnosis of a pinta is carried out by an infectious disease specialist. Examinations by other specialists may be indicated taking into account clinical symptoms. Most often, dermatovenerologists, pediatricians (in case of a child’s illness) and therapists are involved in the diagnosis process. The examination program includes the following instrumental and clinical laboratory methods:
- Physical examination. On the part of internal organs and systems, gross pathology is usually not detected. On the skin and mucous membranes, depending on the stage of the disease, a chancre or a pink dense spot with peeling and daughter chancres is found; vesicles and papules with wetness, lichenization and scratching due to pronounced itching. Often there is onychodystrophy, dyschromia of the skin to areas of vitiligo, hyperkeratosis of the palms and soles. Possible lymphangiitis, inflammation of regional lymph nodes, pyoderma.
- Laboratory tests. There are no changes in the general blood test, after the addition of secondary infections, leukocytosis, neutrophilosis, acceleration of ESR is determined. Biochemical parameters are usually normal, there is rarely an increase in the activity of ALT, AST and CRP, a decrease in total protein. General clinical urine analysis is unchanged, with complications and fever, minor (trace) proteinuria, erythrocyturia, and an increase in urine density are possible.
- Identification of infectious agents. The main method of detecting spirochetes is dark-field microscopy of a fresh preparation (separated chancre, scrapings from pintids). A significant role is played by serological diagnostics with pinta and pale treponema antigens. The PCR technique is currently used only in research. Immunochromatographic rapid tests with capillary blood have been developed.
- Visualization methods. Chest x-ray, CT and MRI of the brain are prescribed if there are indications and for differential diagnosis. ECG and echocardiography are used to exclude heart and vascular lesions. Ultrasound examination of lymph nodes and soft tissues is indicated for patients with suspected infectious and vascular complications. Abdominal ultrasound, retroperitoneal space is necessary to exclude similar pathologies.
Differential diagnosis is carried out with infectious diseases (leprosy, tuberculosis, infectious), non-venereal trepanematoses (yaws), contagious (trichophytia, syphilis, pink lichen) and non-contagious (psoriasis, eczema, allergic dermatitis) skin and venereal diseases. A distinction is required with therapeutic (systemic lupus erythematosus, pellagra, chloasma) and surgical (purulent lymphadenitis, furuncle, cellulite) pathologies having a similar clinical picture.
Therapy is carried out on an outpatient basis, hospitalization is indicated in the presence of complications. Bed rest is not required, it is recommended to exclude potential allergens from food (cocoa-containing products, citrus fruits). Etiotropic therapy involves the use of penicillin and cephalosporin antibiotics, macrolides, usually in tablet forms. The appointment of tetracyclines is possible. Local treatment and surgical treatment of the wound are necessary in the presence of purulent processes, include treatment with antiseptic agents, regular dressings. Symptomatic treatment is carried out with the use of antipyretic and desensitizing drugs.
Prognosis and prevention
The prognosis for uncomplicated course, timely diagnosis and unburdened premorbid background is favorable. The complication rate does not exceed 1-3%, no fatal cases of pinta have been registered. Lesions of the skin disappear within 6-12 months after healing, foci of depigmentation can persist for life. Cases of repeated pinta disease in convalescents have been described, but the infection was abortive in nature. Specific prevention has not been developed. Contact persons are shown prophylactic administration of antibiotics. Preventive measures are non-specific, including improving housing conditions, personal hygiene, improving public access to medical care in endemic areas, and the destruction of blood-sucking insects. Early detection and treatment of patients is considered an effective measure to combat the spread of pint.