Pulmonary candidiasis is an invasive lesion of the lung tissue by yeast–like fungi of the genus Candida, penetrating into the respiratory tract mainly from endogenous foci of mycosis. Fungal infection is manifested by a strong cough with scanty sputum, hemoptysis, subfebrility, shortness of breath, chest pain, weakness, the development of bronchospasm, pleurisy, respiratory failure. To confirm the diagnosis, chest X-ray, sputum microscopy, cultural and serological studies are indicated. Therapy includes antimycotic drugs, adaptogens, vitamins, immunomodulators, bronchodilators and mucolytics, antihistamines.
ICD 10
B37.1 Pulmonary candidiasis
Meaning
Pulmonary candidiasis is a yeast fungal infection that develops in the pulmonary parenchyma against the background of immune insufficiency. In pulmonology, disease occurs in various clinical variants: in the form of candidiasis pneumonia (focal, lobar, chronic); miliary pulmonary candidiasis; post-candidiasis pneumofibrosis; cavernizing types of candidiasis and secondary candida infection of tuberculous caverns; lung mycoma caused by Candida fungi. The isolated form of disease develops less frequently than the manifestation of the generalized form and candidasepsis. Disease occurs in patients of all age groups – from infants to the elderly.
Pulmonary candidiasis causes
The causative agent of pulmonary candidiasis is yeast-like fungi of the genus Candida (more often C. albicans) – conditionally pathogenic microorganisms normally present on the surface of the mucous membranes of the digestive tract, genitals, oral cavity, upper respiratory tract. Candidacy is found in 30-80% of practically healthy people. Exogenous lung damage by candida is possible, but is not etiologically significant. In most cases of pulmonary candidiasis, the dominant role belongs to the endogenous source of infection. Candida fungi penetrate into the lung tissue by aspiration of the secretions of the oral cavity, trachea, bronchi or stomach contents (primarily), as well as due to lymphohematogenic spread from the foci of candidiasis in the gastrointestinal tract, genitals (secondarily).
The acquisition of pathogenicity and colonization of tissues and organs by candida occurs in conditions of weakening of the general and local resistance of the organism. A favorable background for the development of pulmonary candidiasis are immunocompromised conditions (HIV infection, AIDS, neutropenia), endocrine disorders (diabetes mellitus, adrenal insufficiency, hypoparathyroidism), severe somatic or infectious-inflammatory pulmonary pathology (bacterial pneumonia, tuberculosis), oncological processes (lung cancer), blood diseases. Immunosuppression is promoted by prolonged treatment with antibiotics, systemic corticosteroids, immunosuppressants, cytostatics, radiation and chemotherapy, chronic nicotine and alcohol intoxication.
With pulmonary candidiasis, exudative-necrotic (at an early stage) and tuberculoid-granulomatous (at a late stage) tissue reactions develop. Initially, small inflammatory foci with necrosis in the center appear in the lung tissue, surrounded by intraalveolar fibrin effusion and hemorrhages. The largest number of foci of inflammation is organized in the middle and lower parts of the lungs. The lumen of small bronchi may be affected, filaments of fungus and abundant leukocyte exudate appear in them. Easily germinating the walls of the bronchi, candida cause their necrosis. The outcome of acute pulmonary candidiasis may be suppuration of foci with the formation of purulent cavities, ulceration and the formation of cavities; the development of subsequent productive tissue reaction, granulation and fibrosis of the lungs. The peculiarity of candidiasis granuloma consists in the absence of caseosis and the presence of fragments of fungi and cellular detritus in its center and lymphocytes on the periphery.
Pulmonary candidiasis symptoms
Pulmonary candidiasis can occur acutely, with pronounced symptoms (including, in the form of a progressive destructive process or a severe septic condition), but is more often characterized by a sluggish, prolonged course and intermittent exacerbations.
The manifestations of candida pneumonia are similar to the symptoms of bacterial or viral pneumonia and are characterized by a strong cough, dry or with little sputum; often – hemoptysis, subfebrile or febrile temperature, shortness of breath, chest pain. Patients complain of a general serious condition – malaise, weakness, profuse night sweating and loss of appetite. Fungal pneumonia is often complicated by the development of pleurisy with the formation of a large amount of colorless or slightly blood-stained effusion. In the miliary form of pulmonary candidiasis, a painful cough with scanty mucous-bloody sputum is combined with bronchospastic attacks on exhalation. With the development of pulmonary candidiasis against the background of antibacterial treatment of the primary disease (bacterial pneumonia, tuberculosis, etc.), after a short period of clinical improvement, the patient’s condition worsens again due to the activation of the mycotic inflammatory process in the lungs.
Candidiasis mycoma of the lung is asymptomatic. It is possible to develop latent, “mute” forms of pulmonary candidiasis in patients with severe pathology (blood diseases, etc.), as well as those on a ventilator. The erasure of the course of pulmonary candidiasis masks it under other chronic inflammatory pathologies of the respiratory tract. Severe course of this disease is observed in young children – they often develop acute or septic forms with a high degree of lethality. Cases of interstitial pneumonia associated with the invasion of Candida fungi are noted in premature infants.
Patients with pulmonary candidiasis often have signs of a disseminated fungal process with lesions of the skin, subcutaneous tissue, abdominal cavity, eyes, kidneys, etc. In the severe course of pulmonary candidiasis, the development of severe respiratory failure is observed. Mortality in candida pneumonia can range from 30 to 70%, depending on the category of patients.
Diagnostics
Diagnosis of pulmonary candidiasis includes radiography and CT of the lungs, bronchoscopy, sputum microscopy, cultural and serological studies of bronchoscopic material and blood. Manifestations of disease are not pathognomonic, but may be accompanied by candidiasis of other organs, anamnestic information about previous candida infection. The auscultative picture is often meager, without clear symptoms, sometimes dry and wet small-bubbly wheezes are heard.
Radiologically, an increase in the pulmonary pattern in the basal zones can be detected at an early stage, later – multiple small infiltrates with indistinct contours in the lower and middle lobes. Reactive changes in the lungs, lymphatic system of the root and mediastinum are determined; pleural effusion, areas of purulent melting (abscesses). It is characterized by a prolonged course and a relatively rapid change in objective data from the lungs and pleura (the appearance and disappearance of thin-walled cavities, effusion), symptoms (from chronic bronchitis and pneumonia to pleurisy and abscess), as well as the results of functional tests.
In acute form, budding cells and pseudomycelia candide filaments are found in bronchial secretions, lung tissue preparations (within the cellular infiltrate, inside the affected alveoli, in the interalveolar septa). There is significant leukocytosis, lymphopenia, eosinophilia, and a sharp increase in ESR in the blood. Inoculations of bronchial secretions on specific nutrient media reveal its abundant contamination with fungi of the genus Candida (more than 1000 colonies in 1 ml). The isolation of candide culture from the blood (fungemia) confirms the candida nature of the disease.
Positive results of serological diagnostics (RNGA, RSC, RNIF, RP) and intradermal tests with candide allergens do not give clear differences between the candida carrier, a patient with pulmonary candidiasis and other variants of candidiasis. An important sign of pulmonary candidiasis is an increase in clinical manifestations (return of persistent fever) when prescribing antibiotic therapy. Differential diagnosis of invasive pulmonary candidiasis is carried out with bronchitis and bronchopneumonia of other etiology, pulmonary tuberculosis, superficial candidiasis of the trachea and bronchi, other fungal lung lesions, sarcoidosis, lymphogranulomatosis and lung cancer.
Treatment for pulmonary candidiasis
With pulmonary candidiasis, etiotropic therapy with antimycotic drugs is prescribed as a basic treatment – systemically and in the form of inhalations. Oral administration and intravenous administration of fluconazole are recommended, with low sensitivity to it, candide can be replaced with caspofungin, itraconazole. In the presence of neutropenia, combination of pulmonary candidiasis with other visceral forms of mycosis, disseminated process or candidasepsis, there is a need for intravenous administration and inhalation of amphotericin B or mycoheptin. Effective inhalation with sodium salt levorin and nystatin, miconazole, natamycin under the guise of bronchodilators and local anesthetics for the prevention of bronchospasm and adverse reactions. The duration of antifungal therapy is at least 2 weeks after the disappearance of symptoms of pulmonary candidiasis. In severe forms of the disease, increased doses and repeated courses of antimycotics are necessary.
In order to avoid relapses of pulmonary candidiasis, the elimination of background primary pathology is shown by correcting the immunodeficiency state, endocrinopathy, hypovitaminosis, etc. Tonic preparations, adaptogens, vitamin and mineral complexes, immunomodulators, expectorants, antihistamines and detoxification agents are used. Additionally, local warming ointments and massage are prescribed. If the mixed nature of candida infection is detected, antibiotics are added to the main therapy.
With rational therapy of isolated mild forms of pulmonary candidiasis, the prognosis is favorable; with generalized, septic forms of mycosis and delayed treatment, a fatal outcome is possible. Severe chronic course of pulmonary candidiasis leads to disability of the patient. Measures to prevent pulmonary candidiasis are: timely treatment of chronic infectious and inflammatory lung diseases, endocrine disorders, taking antimycotics during antibacterial and hormonal therapy, a healthy lifestyle and moderate physical activity.
Literature
- Ventilator-associated pneumonia in intubated children: comparison of different diagnostic methods. Gauvin F, Dassa C, Chaïbou M, Proulx F, Farrell CA, Lacroix J. Pediatr Crit Care Med. link
- Primary Candida pneumonia. Experience at a large cancer center and review of the literature. Haron E, Vartivarian S, Anaissie E, Dekmezian R, Bodey GP. Medicine (Baltimore). link
- Nonbronchoscopic bronchoalveolar lavage for diagnosing ventilator-associated pneumonia in newborns. Köksal N, Hacimustafaoğlul M, Celebi S, Ozakin C. Turk J Pediatr. link
- Pulmonary disease caused by Candida species. Masur H, Rosen PP, Armstrong D. Am J Med. 1977 Dec;63(6):914-25. link
