What is Sporotrichosis?
Sporotrichosis (Schenck’s disease, Beurmann’s disease, gardeners’ disease, rhinocladiosis) is a chronic infectious disease of the skin and surface lymph nodes caused by various types of filamentous fungi of sporotrichums (Sporothrix schenckii).
Causes of Sporotrichosis
Sporothrix schenckii lives on plants in many parts of the globe. They grow on the remains of plants, in the soil and on the bark of trees, shrubs, and garden plants. Mold is found on the sharp thorns of roses and hawthorn, on mulch, hay, sphagnum moss, and branches of rotten trees. The causative agents of sporotrichosis are found in domestic and wild mammals. In veterinary medicine, cats and horses are the most common carriers. Cats have especially severe forms of cutaneous sporotrichosis.
Sporotrichosis is manifested in the formation of multiple abscesses and ulcerations, affecting mainly the skin and subcutaneous tissue, lymph nodes, less commonly affects the muscles, lungs, bones and internal organs. Sporotrichosis affects people, animals, and insects. It is found everywhere, with the exception of the polar regions, and is most common in the tropics and subtropics. Men get sick more often than women. This is due to the peculiarities of professional activity and less caution of men, compared with women. In developed countries, infection is usually found in adults. The greatest risk of disease is associated with agriculture, horticulture, gardening, berry picking, horticulture and carpentry. In our professional environment, infection is most common among gardeners who work with roses, other traumatic plants, nursery workers working with mosses, hay and soil. This is a professional disease of farmers, gardeners and flower growers.
The frequency of diseases from 1 to 2 cases per million people in the United States, in the underdeveloped countries can reach 1: 1000. First of all, people with weakened immune systems are susceptible to the disease.
Pathogenesis during Sporotrichosis
Infection occurs when Sporothrix schenckii is injected into the subcutaneous tissue in case of minor injuries. Foresters, gardeners, flower sellers become infected with sporotrichosis when in contact with sphagnum, roses and other plants. Infection can develop only at the site of introduction of the pathogen (sporotrichosis chancre) or spread through lymphatic vessels (lymphatic sporotrichosis). Most often affected limbs, beyond their limits the process rarely spreads. The possibility of hematogenous dissemination of the pathogen from the skin lesion has not been proven. Gates of infection in other forms of sporotrichosis – osteo-articular, pulmonary, and others. not installed. Apparently, they are the lungs.
Without treatment, sporotrichosis acquires a chronic course, only occasionally ending on its own. Granulomatous inflammation with the presence of epithelioid and giant cells is characteristic. Inflammatory infiltrate contains clusters of neutrophils.
Symptoms of Sporotrichosis
Sporotrichosis is most often manifested by skin lesions, bone lesions, joint lesions, and pneumonia. In lymphatic sporotrichosis, the most common form of the disease, an almost painless purple papule or knot appears at the site of pathogen introduction. During the following weeks, such nodes are formed along the course of the draining lymphatic vessel. A small amount of pus is periodically released from them; possibly ulceration. This picture – a dense knotted band along the lymphatic vessel – is very characteristic of sporotrichosis. Nevertheless, Nocardia brasiliensis and Mycobacterium marinum cause a similar defeat, less frequently Leishmania braziliensis and Mycobacterium kansasii.
When sporotrichosis chancre in the place of introduction of the pathogen forms a painless granuloma in the form of a papule or node.
In osteo-articular sporotrichosis, monoarthritis or polyarthritis develops, which slowly progresses over many months and years. Usually, elbow, knee, wrist, ankle joints are affected, less often – small joints of hands and feet. Occurs periarticular osteoporosis, visible on the radiograph. Fistulous passages are sometimes formed in the joints. With polyarthritis, hematogenous dissemination of the pathogen into the skin is possible, but none of the secondary skin lesions provide further lymphogenous spread of the pathogen.
Weakening of immunity, including HIV infection, increases the risk of hematogenous dissemination.
In pulmonary sporotrichosis, the lesion is usually represented by a single cavity in the upper lobe of the lung. Chronically current meningitis is possible, even in the absence of damage to the skin and lungs. It is difficult to isolate from the sporothrix schenckii spinal cord.
Diagnosis of Sporotrichosis
The best method for diagnosing sporotrichosis is seeding of pus, synovial fluid, sputum, and skin biopsy. The number of pathogens in tissues can vary considerably. It is not easy to detect Sporothrix schenckii in histological examination of the skin.
In skin forms of sporotrichosis, a saturated solution of potassium iodide is prescribed by mouth, daily increasing the dose (in adults – up to 4.5-9 ml / day) depending on tolerability. Often there are gastrointestinal disorders and acne-like rashes in the upper part of the body and on the face, nevertheless, the treatment should be continued until the site of infection is completely resorbed and for another 1 month. Itraconazole can be used, 100-200 mg / day inside. The drug is effective and well tolerated. In visceral forms of sporotrichosis, iodides are ineffective. More than half of these cases can be cured with amphotericin B (w / w). Itraconazole is sometimes effective, 200-400 mg / day inside.
Forecast. If there is even a small injury, cut or prick with a sharp plant spike, a rapidly expanding area of redness, pain and heat around the wound occurs, you should immediately contact your doctor, warning him about the possibility of a fungal infection.
Sporotrichosis is a benign disease and, with timely diagnosis and complete treatment, in most cases can be cured within a few weeks. The prognosis is always serious with sporotrichosis of the internal organs, lungs, and bones.
We cannot isolate the entire mold in nature. Moreover, many mold fungi are very useful. Also, you do not throw your favorite cat on the street just because it can potentially give you a disease. The most important step in preventing sporotrichosis is to prevent mold spores from getting under the skin. Wearing gloves, boots and protective clothing when working in a garden, vegetable garden, in a nursery should be the rule.
When working with houseplants, also protect your hands from cuts and generations with sharp thorns. Protect your eyes and respiratory organs when working with plant dust (cleaning hay, plant residues). The use of gloves when handling animals, protecting the skin from lesions also minimizes the risk of zoonotic infections.