Idiopathic pulmonary hemosiderosis

　　How is idiopathic pulmonary hemosiderosis caused? The following is a brief description:

　　1. Abnormal development and function of alveolar epithelial cells

　　It disrupts the stability of the alveolar capillaries, causing recurrent hemorrhage, but the etiology of the abnormal epithelial cells is not yet clear.

　　2. Abnormal lung elastic fibers

　　Abnormal acidic mucopolysaccharides in elastic fibers weaken and dilate the vascular wall.

　　3. Milk allergy

　　Some children may have a positive skin test to milk, and precipitins to milk antigens are found in the serum. After discontinuing milk, the clinical symptoms disappear.

　　4. Related to exposure to organophosphorus pesticides

　　Pesticides may trigger this disease in some children, but more precise evidence requires further investigation and confirmation.

　　5. Genetic Factors

　　The patients with this disease may have a genetic factor related to consanguineous marriage of their parents, or the onset of the disease in siblings or twins, but there is no genetic confirmation.

　　6. Immune factors

　　The serum IgG, IgA, and IgM levels in patients are elevated, with IgA being more prominent. Some patients have an increased eosinophil count and pulmonary mast cell aggregation. There may be positive antinuclear antibodies and cold globulin antibodies. Some cases respond effectively to adrenal cortical hormones, immunosuppressants, or plasma exchange. All these suggest that the disease is related to immune dysfunction.

　　What diseases can idiopathic pulmonary hemosiderosis trigger? Briefly described as follows:

　　1. It may cause pulmonary hypertension due to extensive pulmonary interstitial fibrosis, followed by the occurrence of pulmonary heart disease and heart failure. A few patients may develop myocarditis, which can be fatal.

　　2. Complications with enlargement of the liver and spleen are also relatively common.

　　3. Complications with ischemic anemia. Due to recurrent spontaneous pulmonary bleeding, iron-containing hemosiderin is deposited in pulmonary macrophages, and most of the iron is lost from sputum, so the anemia of this disease is essentially iron deficiency anemia caused by chronic bleeding. It may be complicated with massive pulmonary hemorrhage and respiratory failure.

　　Idiopathic pulmonary hemosiderosis is more common in children, mainly seen in 1 to 7 years old, with a male-to-female ratio of 2:1 in adults, and no obvious familial history. Symptoms depend on the degree of pulmonary bleeding. Mild persistent chronic bleeding can cause dry cough, fatigue, pallor of the skin, weight loss, and even clubbing. During the acute bleeding period, hemoptysis, coughing up blood, low fever, chest pain, and other symptoms may occur; in the later stage, dyspnea and even heart failure may occur; in the acute phase and secondary infection, obvious moist rales may be heard. Fecal occult blood test is positive.

　　How to prevent idiopathic pulmonary hemosiderosis? Briefly described as follows:

　　1. Diet attentionA few patients may develop the disease due to the intake of milk or certain foods, and these foods should be avoided. Other patients should have a normal diet, which is very important for children to maintain normal growth and development during long-term treatment.

　　2. LifestyleKeep the residence well-ventilated and the air fresh, avoid going to crowded places with polluted air, and do not come into close contact with patients with infectious diseases.

　　What examinations should be done for idiopathic pulmonary hemosiderosis? Briefly described as follows:

　　1. Laboratory examination

　　1. Hemogram. It shows microcytic hypochromic anemia with increased reticulocyte count. Due to iron deposition in alveolar macrophages, it cannot be transported for the synthesis of hemoglobin, resulting in significantly low serum iron and iron saturation, and normal erythrocyte saline fragility test. The peripheral blood eosinophil count may be elevated, and the erythrocyte sedimentation rate may increase. Since hemoglobin is destroyed in the alveoli, the serum bilirubin level can increase, and the serum IgA level can increase. Direct test, cold agglutination test, and heterophile agglutination test may be positive. The serum lactate dehydrogenase level may increase, and the electrocardiogram may be abnormal in patients with cardiac involvement. The presence of typical hemosiderin-laden macrophages in sputum, gastric juice, bronchoalveolar lavage fluid, or lung biopsy tissue is of great significance for diagnosis.

　　2. Lung biopsy and fiberoptic bronchoscopy. When there is a lot of alveolar bleeding, blood can be seen in the bronchus through fiberoptic bronchoscopy. Pathological observations can be made by methods such as fiberoptic bronchoscopy lung biopsy or open chest lung biopsy to clarify the cause of alveolar bleeding.

　　3. Blood gas analysis.

　　4. Pulmonary function test.

　　Secondly, other auxiliary examinations

　　1. X-ray examination.

　　2. Chest CT scan. Chest CT scan can detect early bilateral middle and lower lung diffuse small nodular shadows.

　　What should be paid attention to in the diet of patients with idiopathic hemosiderosis? Briefly described as follows:

　　1. Recommend

　　It is recommended to eat more potassium-rich foods such as oranges, jujubes, celery, etc.; eat more nutritious and easily digestible foods, and appropriately limit salt intake.

　　2. Avoid

　　It is not advisable to consume milk and other heterologous proteins.

　　Currently, there is no effective treatment for idiopathic pulmonary hemosiderosis, and early control of acute attacks is the key to preventing pulmonary interstitial fibrosis.

　　1. During the acute attack, patients should rest in bed, breathe oxygen, stop consuming milk, take hemostatic agents, and anemic patients should be supplemented with iron. Blood transfusion may be required if necessary.

　　2. Adrenal cortical hormones are effective in controlling acute symptoms.

　　3. For patients who are ineffective with adrenal cortical hormone treatment, immunosuppressive azathioprine can be added.

　　4. Plasma exchange can remove the persistent immune injury caused by immune complexes, improving the patient's clinical symptoms, chest X-ray, and pulmonary function.

　　5. Iron removal method. To prevent excessive iron deposition in the lungs from causing lung tissue damage, iron chelating agents can be used to remove the iron deposited in the lungs and prevent the progression of pulmonary fibrosis. Deferoxamine can be used for treatment, which can significantly increase the amount of iron excreted in urine. Due to the certain toxic effects of iron chelating agents, they have not been widely used.

　　6. For patients with concurrent pulmonary infection, pulmonary hypertension, pulmonary heart disease, and respiratory failure, appropriate treatment should be given.