Chicago disease

Chicago disease - the chronic disease concerning deep mycoses, is characterised by formation of granulomas and purulent processes in lungs, a skin, a hypodermic fat, and at a dissimination - in many internals.

Aetiology. The originator - Blastomyces dermatitidis is among diphasic mushrooms. In tissues it looks like round cells in diameter 8-15 microns, on a nutrient medium white, after the brownish coloration, consisting basically colonys are formed of mycelium strands.

In tissues the yeast phase of a mushroom is observed only. At cultivation on fresh medium at temperature 37 C° the mycelium phase can pass in yeast, and at temperature more low 30 C° it again passes in the mycelium. In natural conditions this kind of a mushroom is found in dogs and horses. From laboratory animals white mice are sensitive to a zymonematosis.

Epidemiology. Sources and pathes of a transmission of infection are studied insufficiently. The originator was found in bedrock, in silt. Epidemic flashes among humans and the animal (dogs), bound to stay on coast of the small rivers in timbered district are described. Authentic cases of a transmission of infection from the human to the human or from an animal to the human it is not described. During epidemic flashes children were ill mainly. There are no data about the raised case rate of persons with immunodeficiencyies. Persons with normal immune system were ill usually. Illness was more often observed in the USA, sporadic cases in Canada, Australia, India, France, Italy, Hungary were registered.

Pathogenesis. Infection atriums, possibly, the respiratory tract to what primary lesions of a respiratory organs testify is. Lesions of a skin which also quite often become perceptible at patients, are secondary as a result of drift of an infection contamination from lungs (localisation mainly on the occluded fields of a skin). At generalisation of an infection contamination the originator from lungs gets to various organs (bones, a liver, a lien, the central excitatory system). As a result of an infection contamination allergic rearrangement educes. The tolerated zymonematosis abandons long and durable immunity. At a part infected (about 50 %) the zymonematosis proceeds asymptomatically.

Symptoms and flow. The incubation interval fluctuates from 1 weeks till 4 months. In a clinical picture of a zymonematosis as the basic implications are considered a lesion of lungs and papillomatous - an ulcerative zymonematosis of a skin. Skin lesions educe usually against pulmonary changes, the last are observed almost at all patients whereas skin changes can be absent. The pulmonary form of a zymonematosis can begin gradually as initially-chronic, without the expressed acute phase of illness. There is a general delicacy, tussis, the body temperature raises, but only at some (about 20 %) it exceeds 38 C°, decreases body mass (at 40 %), stethalgias, a dyspnea are frequent. The blood admixing in a sputum becomes perceptible at 30 % of patients. Dry and wet rhonchuses are auscultated. The pleural rub becomes perceptible only at separate sick (10 %). Some patients can have a generalised lymphadenopathy, liver and lien augmentation. Characteristic lesions of a skin become perceptible at 30-80 % of patients.

Much less often (at 20-25 % of patients) the pulmonary form of a zymonematosis begins acutely, proceeds with the expressed fever at all patients, and at 80-85 % it rises above 38 C°. Almost at all patients strong tussis, stethalgias, are auscultated dry and wet rhonchuses. Quite often admixing of blood in a sputum. For this form are uncharacteristic augmentation baking of a lien, a skin lesion, the pleural rub is not auscultated. Process confines in this stage lungs.

The expressed changes of lymph nodes of a mediastinum, focal infiltrates become perceptible, in some of them caverns with irregular contours educe. At a dissimination process grasps many organs, these forms often come to an end with  destruction of the patient.

The skin lesion begins with appearance of a hypodermic nodule on which place the papule is formed, then a vesicle, a pustule turning to an ulcer. On an ulcerative surface papillomatous growths with fine pustules and crusts are formed. The dimensions of a lesion of a skin are gradually enlarged, reaching 2-3 sm in diameter. Can be localised on any field of a skin (more often on arms, feet, the person, breeches). On a lesion place at healing the thin soft cicatrix is formed.

Complications; arthritises, osteomyelites, a brain lesion (a meningitis, brain abscesses).

The diagnosis and the differential diagnosis. To differentiate it is necessary from others it is long proceeding diseases of lungs (a tuberculosis, pulmonary forms of an aspergillosis, a nocardiosis, a histoplasmosis, abscesses of lungs, neoplasms). The big diagnostic value has a characteristic lesion of a skin. For diagnosis acknowledgement use the laboratory methods, allowing to find the originator or an antibody to it. The originator it is possible to secure from pus of dermal lesions, slices biopsy tissues, sputums. For culture reception do sowings on a blood agar and a nutrient medium. For revealing of antibodies various reactions (a complement-fixation test, a blastogenic response with a specific antigen, etc.) are used.

Treatment. Acute forms of a pulmonary zymonematosis can end with recover and without application antimycosis preparations. Chronic pulmonary forms, and especially disseminated, demand long treatment. In these cases Amphotericinum In is prescribed, as well as at an aspergillosis. Last years it is recommended to use a preparation - Ketoconazole which is prescribed long courses. At use concerning a small dose (400 mg a day) was rarely were observed side reactions, are received good results, but at a part of patients (about 10 %) were observed palindromias. At a dose of 800 mg/days often become perceptible side reactions, but there came full recover. At a lesion of a brain the preparation is ineffective.

The forecast. At disseminated forms without treatment all patients perish almost. At other forms the forecast is more congenial.

Preventive maintenance and actions in the locus. Are not developed.