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Diagnosis of exogenous allergic alveolitis
Last reviewed: 23.04.2024
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Clinical examination
Symptoms of exogenous allergic alveolitis do not depend on the type of allergen. In case of acute onset, symptoms resembling flu (chills, fever, headache, myalgia) appear a few hours after a massive contact with the allergen. Appear dry cough, shortness of breath, scattered small- and medium bubble wet rales; there are no signs of obstruction. The picture of asthma is observed in children with atopy. When the allergen is eliminated after a few days or weeks, the symptoms disappear / subside.
Laboratory diagnostics
In the hemogram for this phase of the disease is not characteristic of eosinophilia, sometimes there is a slight leukocytosis with neutrophilia.
Instrumental methods
On the roentgenogram of chest organs, changes are noted in the form of small (miliary) focal shadows located mainly in the middle of the lungs. Sometimes describe a picture of a decrease in the transparency of the lung tissue - a symptom of "frosted glass." Multiple infiltrative cloud-like or more dense shadows, characterized by reverse development during weeks and months, can also be noted. In some cases, pronounced radiographic changes are not observed. Exogenous allergic alveolitis is characterized by the disappearance of radiological changes after the termination of contact with the allergen (especially against the background of glucocorticoid therapy).
When the FVD is studied, there is a decrease in the vital capacity of the lungs (up to 30% of the required value), sometimes signs of obstruction (decreased patency of small bronchi, hyperinflation of the lungs). These indicators are normalized when contact with the allergen is discontinued.
Repeated exposure to an allergen provokes relapses of the disease, which are longer and more severe. Often the exacerbation is subacute and remains unrecognized, which leads unexpectedly for the patient and the doctor to the transition of the disease to a chronic form.
Clinical examination
For the chronic form of the disease, constant dyspnoea, cough with separation of mucous sputum are typical. With exercise, dyspnea increases, cyanosis develops. At auscultation constant crepitating wheezing is heard. Gradually worsens the state of health, there is weakness, fatigue, decreased appetite and weight loss, decreased motor activity. The deformity of the chest in the form of its flattening is visually determined, changes like "drum sticks" and "watch glasses" develop.
Laboratory diagnostics
In the biochemical analysis of blood, no specific changes are observed. The parameters of humoral and cellular immunity are within the normal range. Characteristic is an increase in the level of circulating immune complexes.
Instrumental methods
In the study of HPD, a restrictive type of ventilation disorders is noted. The parameters of the vital and general lung capacity decrease, the lung dilatability decreases, according to the data of bodipletizmography, the specific bronchial conductivity increases. Diffusive ability of the lungs is reduced due to thickening of the alveolar-capillary membrane and violation of ventilation-perfusion relations. Hypoxemia is expressed at normal values of p a 0 2.
X-ray changes are significant: diffuse amplification and deformation of the pulmonary pattern due to fibrous thickening of the pulmonary interstitium. In the future, cystic enlightenment can be detected.
Bronchoscopic picture is not changed.
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