Idiopathic fibrosing alveolitis in children

Idiopathic fibrosing alveolitis (ICD-10 code: J84.1) is an interstitial lung disease of unknown etiology. Medical literature uses synonyms: Hamman-Rich disease, acute fibrosing pulmonitis, fibrous dysplasia of the lungs. Idiopathic fibrosing alveolitis is rare in children.

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What causes idiopathic fibrosing alveolitis in children?

Family cases of the disease indicate a possible genetic predisposition. The pathogenesis of idiopathic fibrosing alveolitis is caused by fibrosis of the lung tissue, deposition of immune complexes in the alveolar capillaries, and the influence of organ-specific antibodies. The pathological process is localized in the alveolar interstitium, which leads to its diffuse fibrosis.

Symptoms of idiopathic fibrosing alveolitis

The acute onset of the disease is characterized by fever, dyspnea, and dry cough. The onset of the disease is often subacute - complaints of increased fatigue, rare cough, and dyspnea only during physical exertion appear. As the disease progresses, dyspnea increases, the chest flattens, its excursion and circumference decrease, the amplitude of respiratory movements decreases, body weight and height lag behind the norm, deformations of the distal phalanges of the fingers in the form of "watch glasses" and "drumsticks" appear and increase, acrocyanosis and cyanosis of the nasolabial triangle become permanent. Scattered fine-bubble moist or crepitant rales are heard on auscultation.

Idiopathic fibrosing alveolitis has a steadily progressive course. The pressure in the pulmonary artery increases with the formation of chronic pulmonary heart disease and right ventricular failure. Often, with idiopathic fibrosing alveolitis, complications develop in the form of arthritic syndrome, spontaneous pneumothorax, pleural exudates, and rarely - pulmonary embolism.

Diagnosis of idiopathic fibrosing alveolitis

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Laboratory diagnostics of idiopathic fibrosing alveolitis

Characteristic of idiopathic fibrosing alveolitis are changes in the immunogram: increased IgG content (up to 2000-4000 mg/l) and circulating immune complexes (up to 150 IU). An increase in ESR is also noted.

Instrumental diagnostics of idiopathic fibrosing alveolitis

At the early stage of the disease, the X-ray picture of the chest organs may not have any changes. Subsequently, a decrease in the transparency of the lung tissue (the "ground glass" symptom), a reticular-cordial pattern, and small focal shadows are revealed. As fibrosis progresses, ligamentous compactions and cellular enlightenment appear, the pulmonary fields narrow, causing a high position of the diaphragm domes, expansion of the intrathoracic part of the trachea and large bronchi, expansion of the arch and branches of the pulmonary artery, and the formation of a honeycomb lung.

When performing lung scintigraphy, a local decrease in pulmonary blood flow of up to 60-80% is noted. The degree of fibrosis development can be judged by FVD data: restrictive type of ventilation disorders, decreased diffusion capacity of the lungs, decreased elasticity of lung tissue, hypoxemia.

Conducting bronchography is not informative.

During bronchoscopy, neutrophils and lymphocytes predominate in bronchoalveolar fluid cytology. Transbronchial biopsy is informative only in half of cases. Open lung biopsy allows to confirm the diagnosis of "idiopathic fibrosing alveolitis" in 90% of cases.

Treatment of idiopathic fibrosing alveolitis

Treatment of idiopathic fibrosing alveolitis is long-term, complex, with constant correction depending on the course of the disease. Glucocorticoids are combined with immunosuppressants. Hormonal drugs are especially effective in the early stages, when alveolitis prevails over the processes of fibrosis of the lung tissue.

Prednisolone is prescribed at a dose of 1-1.5 mg/kg per day orally for 3-6 weeks. The dose is reduced gradually (by 2.5-5 mg per week). A maintenance dose of 2.5-5 mg/day is taken for 9-12 months. In a rather severe condition and rapid progression of fibrosis, therapy can be started with intravenous glucocorticoids in maximum doses, followed by a transition to oral administration or pulse therapy. In addition to glucocorticoids, D-penicillamine (cuprenil) is prescribed at a dose of 125-250 mg/day for 8-12 months (age-related doses). Courses of basic therapy are periodically repeated.

Treatment of right ventricular failure is carried out according to the traditional scheme in parallel.

It is important to note that exacerbations of the disease are usually provoked by the addition of ARVI, which is difficult to differentiate from bacterial complications, so antibiotics are additionally prescribed. In case of severe respiratory failure (with p _a O ₂ less than 60 mm Hg), a long course of oxygen therapy is prescribed. Light chest massage, special breathing exercises, exercise therapy, plasmapheresis and lymphocytapheresis are indicated. Vitamins and potassium preparations are added.

What is the prognosis for idiopathic fibrosing alveolitis in children?

Idiopathic fibrosing alveolitis in children has an unfavorable prognosis, depending on timely diagnosis and initiation of adequate therapy.