Chronic pulmonary aspergillosis

Definition

Chronic pulmonary aspergillosis is a disease of fungal etiology, which affects all parts of the respiratory system, runs in acute or chronic form, and is characterized by various clinical symptoms and signs of allergy. The clinical picture of the disease includes cough, hemoptysis, fever, and dyspnea. Diagnosis is established based on radiography and CT of the chest organs, bronchoscopy, serologic diagnostics, and laboratory examination of pathologic material. Conservative treatment with fungicides is prescribed, if necessary, in combination with antibiotics and corticosteroids. Aspergillomas are removed surgically.

General information

Aspergillosis of the lung ranks first among pulmonary mycoses in terms of prevalence. 75% of all cases of fungal lesions of the respiratory tract are caused by Aspergillus. The mold fungi that provoke the development of the disease are widespread. The highest content of Aspergillus spores in the environment is found in Arab countries. Their concentration is higher in closed rooms.

People who are forced to come into contact with material contaminated with fungal spores due to their professional activities and patients with immunosuppression of any genesis become ill. Twenty percent of recipients of organs and tissues fall ill with aspergillosis in the postoperative period, and half of them die from the disease.

Causes

The causative agents of the disease are mold fungi of the genus Aspergillus. Their spores are found in air, soil, and water, and their mycelium grows actively in high-humidity conditions. Aspergillus spores are resistant to drying and persist long in dust particles. Flies, cockroaches, and other insects facilitate the spread. People regularly encounter pathogens, and many daily inhale fungal spores, but pulmonary aspergillosis develops in a relatively small part of the population. Risk factors for the occurrence of pathology are:

• Immunodeficiency state. Patients with impaired immune function are susceptible to the disease. Fungal lesions are often detected in persons with primary immunodeficiency, patients with AIDS, cancer, and diabetes mellitus. Mycosis complicates lung transplantation in every fifth patient; somewhat less often, aspergillosis develops in recipients of bone marrow, pancreas, and kidneys. The emergence of pathological conditions is promoted by long-term intake of antibacterial drugs, corticosteroids, and cytostatics.
• Chronic lung pathology. Favorite places of localization of aspergillomas are cavity formations of lung tissue and bronchiectasis. The disease is often diagnosed in patients with chronic forms of tuberculosis, oncopathology of the respiratory system, patients with cystic fibrosis, and COPD.
• Massive aspergillus infestation. People with a normally functioning immune system but working in conditions of massive contamination of the external environment with spores of mold fungi become ill. The risk group includes workers in mills, poultry farms, breweries, farmers, and representatives of other professions. Aspergillus spores in large quantities may be contained in spinning raw materials, ventilation and air conditioning systems, and sanitary equipment.

Classification

There are several classifications of the pulmonary form of the disease. According to the mechanism of infection, exogenous and endogenous aspergillosis of the bronchopulmonary system are distinguished. The process can proceed acutely and chronically. Some specialists in pulmonology separately distinguish the lesion of the lungs and respiratory tract. The working classification reflects the degree of invasion of pathogens, their toxic properties, localization of the process, body sensitization, and the peculiarities of the course of the disease. It includes:

• Non-invasive pulmonary aspergillosis. Single and multiple pulmonary aspergillomas with a relatively benign course occur.
• Invasive aspergillosis of the respiratory tract. Invasive pulmonary forms are isolated necrotizing bronchial aspergillosis, pneumonia, pleuritis, and chronic pulmonary dissemination of fungal etiology.
• Allergic bronchopulmonary aspergillosis. Hypersensitivity to fungal allergens leads to the development of allergic bronchopulmonary aspergillosis – mycogenic bronchial asthma and exogenous allergic alveolitis.

Symptoms of pulmonary aspergillosis

Non-invasive aspergillosis.

The clinical picture in mycotic lesions of the respiratory organs depends on the form of the pathological process. Non-invasive aspergillomas are characterized by an asymptomatic course. It is not possible to determine the duration of the incubation period. The disease is detected accidentally when undergoing a preventive radiologic examination of the lungs. The appearance of blood in the sputum indicates the sprouting of blood vessels with the mycelium of fungi and the beginning of the invasive process.

Invasive aspergillosis

Aspergillus tracheobronchitis or interstitial pneumonia develops if large amounts of pathogens are inhaled. Clinical manifestations are preceded by an incubation period of 1-3 hours to 3 days. There is a persistent, unremitting sensation of bitterness in the mouth and persistence in the throat. There is an increase in temperature to high digits, accompanied by bone pain and chills. Aspergillus pneumonia is characterized by fever of the wrong type. The temperature rises in the morning, decreasing to average or subfebrile values in the evening.

The disease proceeds rapidly. The cough at the beginning is excruciating and attack-like, but it later becomes productive. The bronchi’s gray-green or bloody contents separate. The patient is tormented by shortness of breath, even with a small load. There is intense pain in the chest, intensified by breathing and changing the body’s position.

Chronic aspergillosis

With endogenous infection, pulmonary aspergillosis takes a primary-chronic course. Its clinical manifestations differ from the picture of interstitial pneumonia with sluggish symptomatology with prolonged fever and minor pain syndrome. Mycosis develops against the background of persistent tuberculosis, sarcoidosis, COPD, and other pulmonary pathology and slightly changes the picture of the underlying disease. Patients usually note increased dyspnea and cough and detect gray-green lumps in sputum.

Allergic aspergillosis

Allergic aspergillosis most often occurs in the form of severe hormone-dependent bronchial asthma. It is manifested by frequent day and night attacks of suffocation, wheezing, and heaviness in the chest, and attacks of dry cough. Patients with allergic alveolitis complain of increasing dyspnea and discharge of small amounts of mucous sputum. The acute form of alveolitis is accompanied by signs of general malaise and arthralgia.

Complications

Timely diagnosis and correctly chosen treatment tactics allow recovery in 25-50% of patients with respiratory aspergillosis. Complications occur in any form of the disease. Their frequency and severity depend directly on the immune system’s state and background pathologies. Aspergillosis aggravates the course of the underlying pathological process. 

Patients with aspergillomas often develop hemoptysis. 25% of such patients die of pulmonary hemorrhage. Acute invasive bronchopulmonary aspergillosis with marked immune decline leads to mycogenic sepsis with high (50%) mortality. 

Diagnosis

Patients with pulmonary manifestations of aspergillosis are examined by a pulmonologist. When collecting anamnesis, the occupation, chronic bronchopulmonary pathology, and primary or secondary immunodeficiency are present. During examination and physical examination, a variety of nonspecific symptoms are detected. In Aspergillus pneumonia, widespread dry and moist fine bubbly rales are heard. In other cases, auscultatory data are usually scanty or reflect the course of the background process. The main diagnostic methods are:

• Radiologic diagnosis. The X-ray picture of the lungs is characterized by diversity. Unstable eosinophilic infiltrates, dense round or globular shadows with decay cavities located mainly in the upper lobes of the lungs, and small focal dissemination are determined. 
• Laboratory studies. The general clinical blood test shows leukocytosis, eosinophilia, and elevated erythrocyte sedimentation rate. Microscopy of sputum and bronchial lavage water reveals fungal hyphae. The culture method allows you to grow colonies of Aspergillus on nutrient media. Serological reactions (ELISA) help detect antibodies to mold fungi. Patients with an allergic form of the disease are characterized by a rise in the level of total IgE. In chronic aspergillosis, IgG increases.
• Bronchoscopy. Bronchial endoscopy reveals deformation of the tracheobronchial tree and signs of catarrhal inflammation of the bronchial mucosa. When a bronchoscope gets into the aspergilloma, a fluffy plaque of gray-yellow or greenish color, hardly separating from the walls of the cavity, is detected. Microscopy and culture of the obtained pathological material are performed.

Pulmonary aspergillosis should be differentiated from diseases of a tumor nature, such as tuberculosis, sarcoidosis, and destructive pneumonia, among other etiology. Recently, mycosis has often aggravated the course of the above pathology, so diagnostic searches often involve pulmonologists and oncologists. 

Treatment of pulmonary aspergillosis

The duration of therapy and the scope of treatment measures depend on the form of the disease and the patient’s immune status. Bronchial aspergillosis and non-severe mycotic pneumonia in immunocompetent persons are cured in 7-10 days in outpatient conditions. Indications for hospitalization are hemoptysis, prolonged episodes of febrile fever, and prolonged onset of bronchial asthma. The main drugs used to treat this pathology are antifungal agents active against Aspergillus.

Aspergilloma accompanied by hemoptysis should be surgically removed. Lung resection or lobectomy is performed. In severe respiratory failure, ligation of the bronchial artery is used temporarily to prevent bleeding.

All these treatment options are available in more than 370 hospitals worldwide (https://doctor.global/results/diseases/chronic-pulmonary-aspergillosis). For example, lobectomy can be done in 31 clinics across India for an approximate price of $4,0K (https://doctor.global/results/asia/india/all-cities/all-specializations/procedures/lobectomy). 

Prognosis and prevention

The prognosis is favorable in mild forms of aspergillosis, and full recovery occurs. Chronization of the process leads to the formation of pulmonary heart disease and disability. Expressed immunodeficiency can contribute to the generalization of mycosis and end with the death of the patient. As a preventive measure, persons from occupational risk groups should use personal protective equipment and undergo regular preventive examinations. Patients with marked immune system dysfunction are subject to rational employment and regular serologic examination for aspergillosis. They should avoid eating food with mold and staying in damp and dusty rooms for a long time.