mycosis of the lungs



OVERVIEW

Definition.

Lung lesions caused by different types of fungal infections, the most common deep fungal disease.

Clinical manifestations are nonspecific, with respiratory symptoms predominating.

Classification

There are more ways of classification, such as according to the type of fungus and the main conditions of immune impairment. Clinically common are pulmonary candidiasis, pulmonary aspergillosis, pulmonary cryptococcosis, pulmonary sporotrichosis pneumonia and so on.

By fungal species

Including pulmonary candidiasis and non-candidiasis (e.g., pulmonary cryptococcosis, etc.).

Including pulmonary aspergillosis and non-aspergillosis (e.g., pulmonary trichothecosis, pulmonary penicillinosis of Malnifield, etc.).

Including pulmonary coccidioidomycosis, pulmonary paracoccidioidomycosis, etc.

Including pulmonary sporotrichosis, pulmonary actinomycosis, etc.

According to the main conditions of immune function impairment

e.g. pulmonary histoplasmosis, pulmonary yeast disease, pulmonary coccidioidomycosis, pulmonary paracoccidioidomycosis, pulmonary cryptococcosis, pulmonary sporotrichosis pneumonia, etc.

e.g. pulmonary aspergillosis, pulmonary trichothecosis, pulmonary candidiasis, pulmonary pseudomycosis-like fungal disease, etc.

Morbidity

There is no specific correlation between the incidence of pulmonary candidiasis and gender, season and location; the incidence rate has increased significantly in the past 20 years, and the production of drug-resistant strains has increased.

Pulmonary aspergillosis has no specific prevalence, is worldwide, and the incidence rate has increased in recent years.ABPA accounts for about 1.0%~3.5% in asthma.

Pulmonary cryptococcosis has a worldwide distribution and is highly disseminated; it is most common in young adults; there is no obvious occupational or racial distinction; the incidence rate is often less than 15%.

Pneumocystis carinii pneumonia has no obvious seasonal or gender differences and is distributed worldwide. The incidence rate of Pneumocystis carinii pneumonia can reach 70%~80% in the AIDS population; the incidence rate of non-HIV-infected patients has also increased significantly in recent years. The incidence of Pneumocystis carinii pneumonia can reach 70%~80% in the AIDS population; the incidence of non-HIV-infected patients has also increased significantly in recent years.

Causes

Causes

It is currently believed that pulmonary mycosis is caused by various fungal infections in the lungs.

Fungi attached to the surface of soil, environment, bird droppings, food, etc. multiply and produce spores, which can enter the lungs through breathing and cause disease.

Fungi hosted in parts of the body other than the lungs circulate through the lungs in the blood or lymphatic fluid and cause disease.

Fungi that colonize the lungs can multiply and cause disease when the body’s immunity is reduced by various factors.

Risk factors

Long-term use of medication

Widespread use of medications such as glucocorticoids, antibiotics (broad-spectrum), and immunosuppressants affects or suppresses the body’s immunity, which gives the fungus a chance to develop.

Organ transplantation

After organ transplantation, the body is affected by the rejection reaction and the application of a large number of immunosuppressive drugs, which doubly affects the normal immune function and gives the fungus a chance to multiply and cause disease.

Immunodeficiency

The direct destruction of the immune system function gives the fungus a chance to reproduce and cause disease, as in the case of AIDS.

For example, chronic obstructive pulmonary disease, tuberculosis, bronchiectasis and other chronic structural lung diseases cause the normal physiological function of the lungs to be impaired, the immunity is reduced, so that the fungus has the opportunity to reproduce in large quantities.

Such as uncontrolled or poorly controlled diabetes mellitus, malignant tumors, long-term hospitalization (especially in the intensive care unit), extensive burns, etc., long-term chronic wear and tear leading to metabolic disorders, low immunity or severe infections, etc., the lung fungi can reproduce in large quantities and cause disease.

Pathogenesis

The pathogenesis is not well understood. At present, it is believed that its pathogenesis is related to host factors, pathogen factors and other factors.

Host factors

At the initial stage of fungal colonization in the lungs, the host defense system is normal, which can phagocytose and kill the pathogenic bacteria. With the decline and loss of host immune defense function, the pathogenic bacteria can not be eliminated in time and cause disease.

Pathogen factors

After the pathogenic bacteria colonize the lungs, they produce virulence factors that inhibit the body’s immune defense function and weaken the T-cell immune response, resulting in the onset of the disease.

Symptoms

Main Symptoms

Clinical manifestations are not specific, and most often present with unexplained persistent fever and respiratory symptoms.

Pulmonary candidiasis

Paroxysmal irritating cough, white foamy sputum or glue-like mucous sputum in the form of “pulling silk”, with or without blood, wheezing, shortness of breath, especially at night, which is more serious, and may be accompanied by fatigue, night sweats, mostly without fever.

Manifestation of chills, high fever, cough white foamy sputum, yeast smell, sputum or jelly-like, sometimes hemoptysis, clinical resemblance to acute bacterial pneumonia.

Pulmonary Aspergillosis

Symptoms include dry cough, chest pain, hemoptysis in some patients, and shortness of breath and dyspnea or even respiratory failure when the disease is extensive.

Common symptoms are frequent cough, chest pain, fever and hemoptysis.

Long-term respiratory symptoms as the main manifestation, such as cough, cough sputum.

There may be irritating cough, often repeated hemoptysis, and even life-threatening hemoptysis.

Asthma attacks as its prominent clinical manifestations, the general antispasmodic and asthma drugs are difficult to work. There are also chills, fever, fatigue, irritating cough, cough brownish-yellow pus sputum, etc., occasionally with blood.

Pulmonary cryptococcosis

The onset of the disease is insidious, there may be fever, cough, cough a small amount of white sputum or with shortness of breath, chest pain, sputum blood, weight loss, night sweats, etc., can also be asymptomatic.

Pneumocystis carinii pneumonia (PCP)

PCP is mainly seen in preterm infants and malnourished infants, mostly aged between 2 and 6 months, with insidious onset and slow progression.

Initially, most of them have refusal to sleep, loss of appetite, diarrhea, low fever, weight loss, and gradually dry cough, shortness of breath, and progressive aggravation, dyspnea, nasal flaring and cyanosis occur.

Initial manifestations include lack of appetite and weight loss. This is followed by a dry cough, fever, cyanosis, and dyspnea, which quickly leads to life-threatening respiratory distress.

Consultation

Department of Medicine

Respiratory Medicine

When symptoms such as coughing, sputum and hemoptysis appear, it is recommended to consult a doctor promptly.

Emergency Department

When hemoptysis, respiratory distress or even shock occurs, it is recommended to call 120 or the nearest emergency department immediately.

Preparation

Preparation for medical treatment: registration, preparation of documents, common problems.

Tips for seeking medical treatment

If you have sputum, you can keep it or take a picture of it and bring it with you to the doctor’s office.

If fever occurs, it is recommended to record the temperature change and try not to use fever-reducing drugs by yourself, so as not to affect the judgment of the condition.

Preparation checklist for medical consultation

Especially need to pay attention to the time of symptom onset, special performance, etc.

Are there symptoms such as cough, sputum, hemoptysis, chest pain, dyspnea, chest congestion, shortness of breath?

Is the cough dry, irritating or persistent?

Are there any symptoms such as fever, chills, night sweats, etc.?

(Infants and young children) Are there any signs of weight loss, lack of appetite, or refusal to sleep?

How long have these symptoms been occurring?

Are there any relieving or exacerbating factors?

Is there a history of chronic medical conditions, such as AIDS, diabetes, etc.?

Any chronic lung disease (e.g., COPD, tuberculosis, etc.)?

Is there a history of organ transplantation?

Any long-term or heavy use of medications such as glucocorticoids, antibiotics, immunosuppressants, etc.?

Test results in the last six months, which can be brought to the doctor’s office

Laboratory tests: blood routine, blood biochemistry.

Pathologic examination: G test (serum β-1,3-D-glucan test), GM test (galactomannan test), secretion microscopy or culture results, T lymphocyte test.

Imaging tests: chest X-ray, CT.

Lung function tests.

Medication use in the last 3 months, if available, bring the box or package to the doctor’s appointment

Antifungal drugs: fluconazole, caspofungin, amphotericin B, etc.

Immunosuppressants: cyclosporine, tretinoin, etc.

Glucocorticoid: prednisone, dexamethasone, etc.

Diagnosis

Diagnostic basis

The clinical manifestations of pulmonary mycosis are not specific, and host factors, clinical features, microbiologic examination and histopathologic data must be taken into account in the diagnosis.

Medical history

Generally not used as a basis for diagnosis, but need to ask a detailed medical history and whether there is contact with raw poultry, forests, etc..

There may be a history of chronic lung disease, immunodeficiency diseases.

There may be a history of immunosuppressive drug use, such as immunosuppressants, glucocorticoids, and broad-spectrum antibiotics.

There may be a history of exposure to bird droppings, most often seen in pulmonary cryptococcosis.

Clinical manifestations

As mentioned earlier, most pulmonary mycoses have no specific clinical manifestations.

The presence of more severe clinical symptoms and relatively mild corresponding signs should raise a high level of alertness to the possibility of fungal infection.

The possibility of fungal infection should also be considered in the presence of asthma that is poorly treated with antispasmodic and asthma medications or even ineffective.

Laboratory tests

Microscopic examination and culture of respiratory secretions

Respiratory secretion antigen assay

G test (1, 3-β-D glucan antigen test)

GM test (Galactomannan test)

Latex Agglutination Test

Blood Test

T-lymphocyte test

Determines the type of causative agent and is the gold standard for pulmonary mycoses.

Imaging

It can find out whether there is thickening or loss of lung texture, the presence of nodules or cavities, and the location of the lesion.

X-ray is usually not characteristic, and can be lobar pneumonia, bronchopneumonia, nodular shadow, cavity shadow, mass shadow and other manifestations.

X-ray can be supplemented to understand the lung tissue, blood vessels, morphology, location and so on.

Can be more intuitive, clear understanding of the trachea, bronchial airway wall morphology, blood supply, etc., for some diseases have a role in confirming the diagnosis.

Lung tissue can also be taken under bronchoscopic operation for pathological tissue examination.

Lung function

The total lung volume, diffusion function, tidal volume, etc. can be understood.

Decreased tidal volume, diffusion volume, and total lung volume can be seen in PCP.

Diagnostic criteria

Diagnostic criteria for pulmonary candidiasis

Microscopic examination: competent sputum or bronchial secretion specimen; 2 times both clearly have yeast pseudohyphae or hyphae positive.

Fungal culture: 2 times both have Candida growth and the same species.

G-test: 2 consecutive positive results.

Histopathology: clear Candida infection is the basis for diagnosis.

Diagnostic criteria for pulmonary aspergillosis

Microscopic examination: lung tissue, respiratory tract specimens; there are mycobacterial filaments with acute angle branching separation without pigmentation, about 2~4μm in diameter.

Fungal culture: growth of Aspergillus spp.

GM test: 2 times: consecutively positive.

Histopathology: basis for diagnosis; clear Aspergillus infection.

PCR: suggests the presence of Aspergillus DNA.

Imaging manifestations: lung, brain, sinuses; characteristic manifestations;

Host: immunosuppressed individuals, e.g., use of immunosuppressive drugs, HIV infection, organ transplantation.

Diagnostic criteria for pulmonary cryptococcosis

Microscopic examination: cerebrospinal fluid staining; visible outer ring of translucent, round, thick-walled organisms; basis for definitive diagnosis.

Fungal culture: cryptococcal growth; assists in confirming the diagnosis.

Histopathology: basis for diagnosis; definitive cryptococcal infection. Round posterior walled bodies with translucent outer ring after staining suggests a new type of Cryptococcus.

Latex agglutination test: definitive cryptococcal antigen suggestive of cryptococcal infection.

Diagnostic criteria for Pneumocystis carinii pneumonia

Blood routine: leukocytes about (15~20)x109/L, eosinophils increase, lymphocytes decrease in absolute value.

Blood biochemistry: lactate dehydrogenase is elevated.

Pulmonary function measurements: decreased total lung volume, tidal volume, diffusion volume.

Blood gas analysis: respiratory alkalosis, hypoxemia (partial pressure of oxygen <60 mmhg).

Imaging: solid, butterfly-shaped shadows and bronchial congestion signs in bilateral hilar.

Histopathology: confirmatory basis for diagnosis; definitive sporadic infection.

Differential diagnosis

Lung malignant tumor

Similarity: both have cough, cough sputum or mass shadow and other manifestations.

Differences: lung malignant tumor is consumptive progression, mostly with blood in sputum or hemoptysis, weight loss. Lung fungal disease has no coughing up blood, weight loss and other manifestations. Pathologic tissue biopsy can confirm the diagnosis.

Tuberculosis

Similarities: both have cough and sputum.

Differences: Tuberculosis is characterized by low-grade fever and hemoptysis. Pulmonary mycoses mostly do not have hemoptysis and low-grade fever. Pathologic tissue biopsy can confirm the diagnosis.

Pneumonia caused by other pathogens

Similarities: both have clinical manifestations such as cough and sputum.

Differences: lung fungal disease is ineffective to general antibiotic treatment, and may even be aggravated. Pathologic tissue biopsy can identify.

Treatment

Aim of treatment: improve lung ventilation function, eradicate fungal infection, improve quality of life, prolong survival.

Treatment principle: according to the results of pathogenic bacteria testing, precise implementation of individualized treatment, including general treatment and pathogenic treatment, often based on antifungal drugs, but also can choose other drugs or surgery.

General treatment

Remove triggers.

Strengthen nutrition and rest.

Strengthen supportive therapy, correct electrolyte balance.

Pathogen treatment

Pulmonary candidiasis

Select drugs according to the results of drug sensitivity test of pathogenic bacteria.

Indications: elimination of the causative agent but with severe disease.

Contraindications: allergy, severe hepatic and renal insufficiency.

Adverse reactions: gastrointestinal reactions, dizziness, headache, rash, chills, fever, electrolyte disorders, hepatic and renal injury, thrombophlebitis.

Commonly used drugs:

Pulmonary Aspergillosis

IPA, ITBA, CNPA may be preferred antifungals.

Hormones are preferred for ABPA, and antifungals or antispasmodics may also be used.

Monodrugs are preferred.

Combination of two drugs may be used in cases of ineffective monotherapy, multiple infections, drug resistance, and intolerance.

Contraindications: allergy, severe hepatic and renal insufficiency.

Adverse reactions: chills, fever, back pain, panic, liver and kidney impairment.

Commonly used:

Contraindications: severe systemic infections, hepatic and renal dysfunction.

Adverse reactions: immunosuppression, induced infection, electrolyte disorders, rebound from drug withdrawal.

Commonly used drugs: cortisone, prednisone, prednisone, dexamethasone and so on.

Such as antispasmodic beta 2 agonists (terbutaline, salmeterol, etc.), inhaled glucocorticoids (budesonide, etc.).

Pulmonary cryptococcosis

Asymptomatic and immunocompetent individuals may be followed up with observation or oral fluconazole.

Antifungal therapy is required for those with combined immunosuppression.

Combination of two antifungals is recommended in severe cases or in combination with cryptococcal meningitis.

Surgical resection followed by antifungal therapy is recommended for extensive lobar solid or massive lesions.

Oral fluconazole is recommended postoperatively for those who have surgically resected the mass without preoperative chemotherapy.

In patients with AIDS, HAART (Highly Active Combination Anti-Retroviral Therapy, also known as cocktail therapy) should be administered as early as possible within 2 weeks of antifungal therapy.

Contraindications: hypersensitivity, severe hepatic or renal insufficiency.

Adverse reactions: gastrointestinal reactions, dizziness, headache, rash, chills, fever, electrolyte disorders, hepatic and renal injury, thrombophlebitis.

Commonly used drugs:

Pneumocystis pneumonia

Focused treatment is pathogenic.

Symptomatic treatment and treatment of underlying disease should also be carried out.

Prophylactic chemotherapy is feasible for high-risk groups.

Contraindications: allergy, severe hepatic and renal insufficiency.

Adverse reactions: allergy, leukopenia and hematopoiesis, megaloblastic anemia, folic acid deficiency.

Commonly used drugs: compound sulfamethoxazole, ampicillin, primaquine, clindamycin, methotrexate, atovaquone.

Contraindications: allergy, severe hepatic and renal insufficiency.

Adverse reactions: gastrointestinal reactions, dizziness, allergy.

Commonly used drugs: caspofungin.

Contraindications: severe systemic infection, hepatic and renal dysfunction.

Adverse reactions: immunosuppression, induced infection, electrolyte disorders, rebound from drug withdrawal.

Commonly used drugs: cortisone, prednisone, prednisone, dexamethasone, etc.

Surgery

Indications

The lesion is limited and drug treatment is ineffective for 3-6 months.

If the disease progresses to form cavities or lung abscesses.

Formation of chest wall abscess, fistula, pyothorax.

Those whose lung lesions are close to large blood vessels.

Repeated hemoptysis, concomitant bronchial dilatation and the effect of drug treatment is poor.

Contraindication

Severe cardiopulmonary dysfunction, hepatic or renal insufficiency, asthma, pulmonary heart disease, etc. who cannot tolerate the surgery.

Surgical Procedure

Total lung resection of the affected side.

Segmental or lobar resection of the affected side of the lung.

Wedge resection of the affected lung.

Drainage or extended resection: for chest wall involvement.

Expansion resection: for chest wall fistula formation.

Surgical Precautions

Preoperative and postoperative standardized use of antifungal drugs, antibiotics and other pretreatment.

Oral fluconazole is recommended after surgery for those who have surgically resected cryptococcal infected masses without preoperative chemotherapy.

Postoperative complications

Abscessed chest, recurrence, infection, bronchopleural fistula.

Prognosis

Cure

Prognosis is highly variable from disease to disease.

The 1-year survival rate for untreated chronic necrotizing pulmonary aspergillosis is 50%.

Untreated epidemic Pneumocystis carinii pneumonia can result in death from respiratory failure in about 3 to 8 weeks, with a case fatality rate of about 20% to 50%.

Untreated disseminated Pneumocystis pneumonia has a case fatality rate of about 70-100%.

The incidence and mortality rate are higher in those who develop postoperative complications of invasive pulmonary fungal infections.

Most pulmonary fungal infections have a good prognosis with prompt, aggressive and effective drug therapy.

Those with serious underlying diseases such as diabetes mellitus and malignant tumors often have a poor prognosis.

Hazards

Untimely treatment, a variety of complications such as hemoptysis, bronchiectasis, pulmonary fibrosis, etc. can occur, progressing to irreversible pathological changes.

Untimely treatment, comorbidities or more complications can seriously affect daily life, work, and even life and health.

Daily

Daily Management

Dietary management

Eat a balanced diet with more fruits and vegetables, high protein foods (e.g. dairy products, eggs, soy products).

Ensure adequate calorie intake.

Life Management

Stop smoking and drinking.

Regular work and rest, avoid overwork.

Psychological Support

Adjust your mindset appropriately and maintain a positive and persistent attitude towards treatment.

Confide in negative emotions.

Disease monitoring

During the use of drugs, regular monitoring should be carried out, including blood routine, urine routine, liver and kidney function, electrocardiogram.

Those who are ill should undergo regular review, such as chest imaging, lung function, blood routine, and so on.

Prevention

Actively treat the underlying disease.

Reasonable use of antibacterial drugs, strict control of the dose and course of treatment.

Strictly control the dose and course of hormones.

Minimize or avoid medical factors leading to fungal infection, such as timely removal of deep venous indwelling tubes.

Immunocompromised patients should strengthen supportive therapy.