Berylliosis

Acute and chronic berylliosis is caused by the inhalation of dust or vapors of beryllium compounds and products. Acute berylliosis is currently rare; Chronic berylliosis is characterized by the formation of granulomas throughout the body, especially in the lungs, intrathoracic lymph nodes and skin. Chronic berylliosis causes progressive dyspnea, cough and malaise. The diagnosis is established by comparing the anamnesis, beryllium test of lymphocyte proliferation and biopsy. Treatment of berylliosis is carried out by glucocorticoids.

[1], [2]

Causes of berylliosis

The effect of beryllium is a frequent but unrecognized cause of the disease in many industries, including beryllium mining exploration and production, alloy production, processing of metal alloys, electronics, telecommunications, nuclear weapons, protective equipment, aviation, automotive, space and electronics and computer processing.

Acute berylliosis is a chemical pneumonitis that causes diffuse parenchymal inflammatory infiltrates and nonspecific intralaveolar edema. Other tissues (eg, skin and conjunctiva) can also be affected. Acute berylliosis is currently rare, as most industries have reduced levels of exposure, but in 1940-1970 cases were frequent, and many progressed from acute berylliosis to chronic.

Chronic berylliosis remains a frequent disease in the industries that use beryllium and beryllium alloy. The disease differs from most pneumoconiosis, since it is a cellular reaction of hypersensitivity. Beryllium is represented by CD4 + T-lymphocytes by antigen-presenting cells, mainly in the context of HLA-DP molecules. T-lymphocytes in the blood, lung or other organs, in turn, recognize beryllium, proliferate and form clones of T-lymphocytes. These clones then produce pro-inflammatory cytokines such as TNF-a, IL-2, and interferon gamma. They enhance the immune response, leading to the formation of mononuclear infiltrates and noncaseating granulomas in target organs, where beryllium settles. On average, 2-6% of people exposed to beryllium develop beryllium sensitization (defined as positive proliferation of blood lymphocytes on beryllium salt in vitro), most leading to the development of the disease. Certain high-risk groups, for example those working with beryllium metals and alloys, have a prevalence of chronic berylliosis of more than 17%. Workers who have indirect contacts, such as secretaries and guards, are also prone to developing sensitization and disease, but more rarely. Typical pathological changes are the diffuse granulomatous reaction of the lymph nodes of the lungs, roots and mediastinum, histologically indistinguishable from sarcoidosis. Early formation of granulomas with mononuclear and giant cells can also occur. If the cells are washed out of the lungs during bronchoscopy, a large number of lymphocytes are found (bronchoalveolar lavage [BAL]). These T-lymphocytes proliferate if they are exposed to beryllium in vitro, to a greater extent than blood cells (beryllium lymphocyte proliferation test [BTLC]).

[3]

Symptoms of berylliosis

Patients with chronic berylliosis often have shortness of breath, cough, weight loss and a very volatile chest X-ray picture, usually characterized by diffuse interstitial consolidation. Patients complain of sudden and progressive dyspnoea with physical exertion, cough, chest pain, weight loss, night sweats and fatigue. Symptoms of berylliosis can develop within months after the first contact or more than 40 years after the cessation of exposure. In some people, the disease remains asymptomatic. Chest X-ray can be normal or reveal scattered infiltrates, which can be focal, reticular or have the appearance of frosted glass, often with root adenopathy, recalling the changes characteristic of sarcoidosis. Also there is a miliary structure. Chest X-ray with high resolution is more sensitive than conventional radiography, although cases of biopsy-proven disease are found even in patients with a normal picture obtained by imaging techniques.

Diagnosis of berylliosis

The diagnosis depends on the anamnesis of the contact, adequate clinical manifestations and pathological blood tests and / or BALF BTPL. BAL BTPL is very sensitive and specific, helping to distinguish chronic berylliosis from sarcoidosis and other forms of diffuse lung diseases.

[4], [5], [6], [7], [8]

Treatment of berylliosis

Some patients with chronic berylliosis never require treatment because of the relatively slow progression of the disease. Treatment is carried out by glucocorticoids, which lead to symptomatic recovery and improvement of oxygenation. Treatment of berylliosis usually begins only in those patients who have significant symptoms and signs of abnormal gas exchange or a rapid decrease in lung function or oxygenation. Symptomatic patients with impaired pulmonary function are prescribed prednisone at a dose of 40 to 60 mg orally 1 time per day or every other day for 3-6 months, after which the lung physiology and gas exchange parameters are re-examined to document the response to therapy. After that, the dose gradually decreases to the lowest, which is able to maintain a symptomatic and objective recovery (usually about 10-15 mg once a day or every other day). Usually requires life-long therapy with glucocorticoids. There is an astonishing indication that the additional appointment of methotrexate (10-25 mg orally once a week) can reduce the dose of glucocorticoids in chronic berylliosis, similar to that observed in sarcoidosis.

In acute berylliosis, edema and hemorrhages in the lungs often develop. In severe cases, artificial ventilation is required.

Unlike many cases of sarcoidosis, spontaneous recovery in chronic berylliosis occurs rarely. In patients with chronic berylliosis in the terminal stage, lung transplantation can be a means of saving lives. Other supportive measures, such as supplemental oxygen therapy, pulmonary rehabilitation and drugs for treating right ventricular failure, are used as needed.

How to prevent berylliosis?

Reducing the amount of industrial dust is the main means of preventing beryllium exposure. Effects should be reduced to levels that should be as low as possible, preferably more than 10 times lower than existing OSHA standards - to reduce the risk of sensitization and chronic berylliosis. Medical observation using a BTFT study of blood and chest X-ray is recommended to all exposed workers, including those with direct or indirect contact. Berylliosis (both acute and chronic) should be quickly recognized, and sensitized workers are removed from further contact with beryllium.

What is the prognosis of berylliosis?

Acute berylliosis can be fatal, but the prognosis is usually good if patients do not progress to chronic berylliosis. Chronic berylliosis often leads to a progressive loss of respiratory function. Early disorders include an obstructive type of breathing disorder and reduced oxygenation when examining the gas composition of the blood at rest and under load. Reduced diffusion capacity of carbon monoxide (DL ^) and restriction appear later. Pulmonary hypertension and right ventricular failure develop in approximately 10% of cases, leading to death from the pulmonary heart. Beryllium sensitization progresses to chronic berylliosis in approximately 8% of sensitized patients diagnosed during medical examinations per year. Subcutaneous granulomatous nodules caused by the encapsulation of beryllium dust or splinters are usually preserved until excision.