Interstitial lung disease in children



OVERVIEW

Interstitial lung disease in children is a chronic lung disease occurring in children characterized by imaging diffuse exudates and impaired gas exchange.

The various levels of bronchioles and alveoli within the lungs are called the lung parenchyma, and the connective tissue, lymphatics, nerve cells, and blood vessels outside the lung parenchyma are collectively referred to as the interstitium.

Interstitial lung diseases are diffuse parenchymal lung diseases that occur within the interstitium and may also involve the alveolar and bronchiolar cavities.

Epidemiology

Some studies suggest that there are approximately 1.32 new cases of interstitial lung disease per million children.

One estimate suggests that there are approximately 3.6 cases of the disease per million children aged 0-16 years.

Classification

Classification of interstitial lung disease in children developed by the American Thoracic Society (2013)

Lung disease occurring in infants: also categorized as diffuse lung developmental disorders, surface-active substance dysfunction, growth abnormalities, and specific types of disease of unknown cause.

Diseases not specific to infants: includes diseases occurring in previously healthy children, diseases occurring in children with immunodeficiencies, diseases associated with systemic illnesses, and diseases similar to interstitial lung disease.

Interstitial lung diseases that cannot be categorized: e.g., end stage of lung disease.

Classification according to etiology

Allergic pneumonia: caused by inhalation of allergic substances.

Eosinophilic pneumonia: also known as pulmonary infiltrates with eosinophilia syndrome.

Lipoid pneumonia: caused by inhalation of lipids in the lungs.

Idiopathic interstitial pneumonitis: the etiology is still unclear, according to the clinical manifestations, imaging manifestations and pathological changes can be divided into the following seven types.

Idiopathic pulmonary fibrosis: also known as fibrogenic alveolitis, with histologic manifestations of common interstitial fibrosis.

Nonspecific interstitial pneumonia: histology also shows nonspecific interstitial pneumonia.

Cryptogenic opportunistic pneumonia: histology shows opportunistic pneumonia.

Acute interstitial pneumonia: histology shows diffuse lung damage.

Respiratory bronchiolitis with interstitial pneumonia: histologic manifestation of respiratory bronchiolitis.

Desquamative interstitial pneumonia: histologic manifestation of desquamative interstitial pneumonia.

Lymphocytic interstitial pneumonia: histologic manifestation of lymphocytic interstitial pneumonia.

Causes

Causes

Environmental factors

Inhalation of organic dust: such as plant, animal and man-made organic dust, common cotton, tobacco, wood chips, feathers, fur, animal excreta and man-made fibers.

Inhalation of inorganic dust: such as lead, manganese, cement, glass fiber, etc.

Inhalation of harmful gases: nitrogen oxides, sulfur dioxide, metal oxides, hydrocarbon compounds and diisocyanotoluene, etc.

Disease factors

Congenital diseases: such as pulmonary alveolar dysplasia, congenital alveolar dysplasia, congenital alveolar dysplasia, alveolar capillary dysplasia with pulmonary vein misalignment, congenital alveolar proteinosis, congenital heart disease, etc.

Acquired immunodeficiency diseases: acquired immunodeficiency syndrome (AIDS), etc.

Infectious diseases: such as viral pneumonia, mycoplasma pneumonia, chlamydia pneumonia, etc.

Other diseases: such as leukemia, tuberculosis, etc.

Treatment factors

e.g. chemotherapy, pulmonary intervention, chest radiotherapy, etc.

Pathogenesis

Inflammatory and immune responses due to a variety of known or unknown etiologic factors lead to damage to the alveolar walls, vessel walls, and airways, followed by irreversible lung scarring (fibrosis), which ultimately leads to impaired alveolar gas exchange.

Risk factors

Infections: Pneumocystis carinii, bacterial, viral, parasitic infections, etc.

Gastroesophageal reflux: gastroesophageal reflux causing microinhalation may increase the risk of developing the disease.

Genetic factors: a family history of interstitial lung disease may increase the risk.

Symptoms

Typical symptoms

Shortness of breath

This is characterized by shortness of breath.

Shortness of breath can occur when quiet.

Cough, asthma

May be a dry cough or may be accompanied by coughing up sputum.

Blood may be present in the sputum, but this is rare.

Cough may be accompanied by shortness of breath with a distinct breath sound (asthma).

Dyspnea

Difficulty in breathing may be characterized by shortness of breath, shallow amplitude and rapid rate.

The degree of dyspnea may worsen as the disease gets worse.

Other symptoms

Symptoms such as chest pain, fatigue, weight loss, muscle aches and pains, and swollen joints may occur.

Pestle-like fingers (toes): manifested as hyperplasia and hypertrophy of the ends of the fingers or toes, and the fingers or toes are like drumsticks.

Cyanosis: manifested as cyanosis of lips, fingers (toes) and nail beds.

Complications

Pulmonary encephalopathy: mainly manifested as indifference, muscle tremor or fluttering tremor, intermittent convulsions, lethargy or even coma.

Respiratory failure: mainly manifested as dyspnea, cyanosis, unconsciousness, etc. It may involve all systems of the body and cause multi-organ dysfunction.

Consultation

Situations that require medical attention

Children with shortness of breath, cough, dyspnea, etc. should consult a doctor promptly.

Suggested departments

Pediatrics, Pediatric Internal Medicine.

If symptoms such as shortness of breath occur, immediately call “120” for help and go to the emergency department.

Preparation

If there are no special circumstances, you need to register through the hospital’s official website, official app, 114 and other regular channels, prepare your social security card (medical insurance card) and other medical documents, bring your previous medical documents, and apply for a record for those who are traveling to a different place for medical treatment.

Emergency department visits can be registered directly, without the need to register through the above channels. The social security card and previous medical documents can be replenished at any time during the visit. Those who seek medical treatment from other places do not need to file a record.

What questions the doctor may ask

What’s wrong with the child? How long has the discomfort lasted?

Is there a fever? What is the highest degree of fever?

Is there a cough? Is there phlegm when coughing? Is the amount of sputum large or small? Is the phlegm sticky?

Is there frequent exposure to dust, harmful gases?

Are there any congenital diseases, autoimmune diseases? What are they?

Are there any other chronic diseases?

Have tests been performed? What are the test results?

Are there any asthma, congenital heart diseases?

Are there any pollen, food, or drug allergies? If so, to which substances are they allergic?

Was born at full term?

Questions you can ask your doctor

Why do I get interstitial lung disease in children?

How is interstitial lung disease in children different from other types of pneumonia?

Is it contagious to others?

What tests are needed?

How is it treated?

What do I need to be aware of in my daily life?

Diagnosis

Disease Diagnosis

Medical history

Frequent exposure to dust, harmful gases, etc.

Suffering from congenital diseases, immunodeficiency diseases, infectious diseases, leukemia, etc.

Undergoes chemotherapy, interventional therapy of the lungs, chest radiotherapy, etc.

Clinical manifestations

Symptoms

Symptoms such as shortness of breath, cough, dyspnea, chest pain, chest tightness and cyanosis.

Physical signs

Systemic examination: hyperplasia and hypertrophy of the ends of the fingers or toes with pestle-like enlargement can be seen. If there is right heart failure, there may be jugular vein rage, edema and other manifestations.

Chest auscultation: Bursting rales can be heard at the bases of the lungs bilaterally, and wheezing and wet rales may be present or may be completely normal.

Laboratory tests

Routine blood tests: white blood cells and neutrophils may be elevated in the presence of infection.

Urinalysis: In the presence of kidney damage, there may be increased red blood cells in the urine and urinary protein.

Arterial blood gas analysis: can understand the respiratory function of the child.

Erythrocyte sedimentation rate: there is often an increase.

C-reactive protein: often elevated.

Immunologic tests: may be abnormal if autoimmune disease is present.

Imaging tests

Chest X-ray: can detect lesions of lung structures and certain signs may suggest a specific diagnosis. It is common to see “ground glass” changes in the lungs, reticular changes, honeycomb lungs, and enlarged mediastinal and hilar lymph nodes.

Chest CT: It can detect interstitial lung lesions that are not easily detected by conventional chest X-ray, and can clarify the location and severity of the lesions.

Echocardiography: It helps to check the structure and function of the heart and clarify whether the child has congenital heart disease.

Other tests

Lung function test: It can detect the type of lung dysfunction and its severity.

Histopathological examination: Samples can be obtained through fiberoptic bronchoscopy, bronchoalveolar lavage, open chest surgery, etc., depending on the condition, for histopathological examination, which helps in the diagnosis of the disease.

Differential Diagnosis

Tuberculosis

Similarities: Fever, cough, etc.

Differences: Tuberculosis is a disease caused by Mycobacterium tuberculosis infection, and is mostly transmitted by inhaling droplets from patients with tuberculosis. Fever is usually low and may be accompanied by emaciation. It can be differentiated by the tuberculin test.

Lobar pneumonia (alveolar pneumonia)

Similarities: Fever, cough, chest pain, etc.

Differences: Lobar pneumonia is an inflammatory disease caused mainly by Streptococcus pneumoniae, with diffuse fibrinous exudation in the alveoli as the main pathological change, and the lesion usually involves all or most of the lobes of the lungs. It can be differentiated, for example, by imaging.

Lobular pneumonia (bronchopneumonia)

Similarities: Fever, cough, dyspnea, etc.

Differences: Lobular pneumonia is an inflammation of the bronchial walls and alveoli caused by bacterial, viral or other infections. Chest auscultation can be heard medium and fine wet rales, combined with imaging, laboratory tests, etc. can be distinguished.

Treatment

Aims of treatment: to slow down the progression of the disease, to improve the quality of life, and to ensure growth and development.

Treatment methods: general treatment, drug treatment, etc.

General treatment

Health management

For interstitial lung disease clearly caused by environmental factors, it is important to get out of the bad living environment as soon as possible and stay away from allergens.

Parents and other family members should quit smoking to avoid second-hand smoke.

Actively treat the primary disease.

In severe cases, respiration, heart rate, blood pressure, and oxygen saturation should be closely monitored in order to understand the condition of the child and the effect of treatment.

Oxygen therapy

Nasal catheter oxygen may be used for mild to moderate hypoxemia.

Mask oxygenation is generally suitable for children who need higher oxygen concentration.

If necessary, long-term home oxygen therapy can be performed under the supervision of a doctor.

Do not adjust the oxygen flow rate when administering oxygen therapy.

Nutritional support

Ensure adequate nutrition.

Breastfeeding children should be ensured the amount of breastfeeding.

For children who cannot eat by mouth, a nasogastric tube or nasojejunal tube can be placed.

Rest

Ensure adequate sleep, avoid exertion and stay up late.

For those who have been lying down for a long time, they should be turned over and patted on the back regularly to keep the airway open.

Medication

There are many types of interstitial lung diseases, and the following medications should be used to slow down the progression of the disease and reduce the symptoms. They should be used under the guidance of a doctor. Do not believe in unidentified treatments such as local remedies, secret remedies and biased remedies.

Anti-inflammatory treatment

Glucocorticoid

Prednisone and methylprednisolone can be used.

If the disease is serious, high-dose glucocorticoid shock therapy can be applied as appropriate.

If the clinical symptoms are relieved and stabilized, the dosage can be reduced or stopped according to the doctor’s opinion.

Long-term application of glucocorticosteroids should pay attention to infection, osteoporosis, gastrointestinal bleeding, hypokalemia and other adverse reactions.

Immunosuppressant

Immunosuppressants combined with glucocorticoids can enhance the therapeutic effect.

Cyclophosphamide, methotrexate and azathioprine are commonly used.

In the treatment, attention should be paid to check the blood and urine routine and liver function and renal function to monitor the occurrence of adverse reactions.

Anti-infection treatment

Under the condition of smooth drainage of respiratory secretions, effective anti-infective drugs should be selected with reference to the results of sputum bacterial culture and drug sensitivity test.

β-lactams (e.g. cephalosporins, penicillins) combined with macrolides (e.g. erythromycin, azithromycin) may be used for drug treatment. quinolones are contraindicated under 18 years of age.

Eosinophilic pneumonia associated with parasites should be treated with deworming.

Antifibrotic drugs

In some children, N-acetylcysteine can be used, which has an antioxidant effect and thus an antifibrotic effect, as well as relieving coughing symptoms.

Pirfenidone and nidazanib can slow down the decline of lung function, but the safety of pirfenidone and nidazanib in children under 18 years of age has not been established, and they should be used with caution according to medical advice.

Other treatments

Bronchoalveolar lavage therapy: for alveolar microlithiasis, alveolar sex protein deposition.

Lung transplantation: for hereditary abnormalities of lung surfactant metabolism, abnormalities of the surfactant protein C gene.

Prognosis

Cure

Allergic pneumonitis: some children’s symptoms may disappear on their own and lung function may be restored a few days after they are removed from the adverse environment and away from the allergens.

Interstitial pneumonia associated with connective tissue disease or vasculitis: prognosis depends on the severity of the primary disease.

Idiopathic pulmonary fibrosis: the average survival time after diagnosis is 3 to 5 years, and the most common causes of death are respiratory failure, heart failure, ischemic heart disease, infection, and pulmonary embolism.

Idiopathic nonspecific interstitial pneumonia: the vast majority of children have a good clinical prognosis, and their condition may be stable or improve with treatment, but some of them continue to progress to end-stage fibrosis or even die.

Respiratory bronchiolitis with interstitial lung disease: most children have a good prognosis, and their condition may stabilize or improve after active or forced smoking cessation.

Desquamative interstitial pneumonia: most have a good prognosis.

Cryptogenic opportunistic pneumonia: most children may have remission after treatment, and a few may remit on their own.

Acute interstitial pneumonia: children with sudden onset and rapid progression, respiratory failure can occur in a relatively short period of time, the average survival time is very short, most of them die in 1 to 2 months.

Idiopathic lymphocytic interstitial pneumonia: some children may resolve completely with treatment, and some may remain relatively stable for months or years before progressing to pulmonary fibrosis and pneumogenic heart disease.

Hazards

Coughing, shortness of breath, and dyspnea affect children’s eating, playing, and can even interfere with their lives.

It can cause complications such as respiratory failure and pulmonary encephalopathy, which can be life-threatening in severe cases.

Everyday

Daily life

Ensure adequate and balanced nutrition

Ensure the intake of protein, unsaturated fat, vitamins, minerals and dietary fiber. Older children can choose beans, dairy, meat, fish, fresh fruits, fresh vegetables and nuts.

Breastfeeding children should ensure that they are breastfed or artificially fed and that complementary foods are added in a timely manner.

Avoid fried, pickled and barbecued foods.

Ensure daily water intake, and increase water intake appropriately when fever develops.

Avoid raw, cold, hard and hot food, chew slowly and avoid overeating.

Improve living habits

Stay away from “second-hand smoke” (avoid passive smoking).

Ensure adequate sleep and avoid staying up late.

Exercise in moderation. Avoid excessive exercise.

Soothe your emotions

Avoid stress, anxiety, anger, depression and other negative emotions.

Parents should pay attention to channeling the emotions of the affected children.

Improve the environment

Ventilate the room by opening windows and windows to ensure fresh air.

Observe the weather and increase clothing in cold weather.

Wear warm hats, masks, gloves and socks when going out.

Preventing Infection

Avoid going to places where people gather.

Pay attention to personal hygiene and wash hands frequently.

Get vaccinated against influenza and pneumonia in winter and spring as appropriate.

Regular checkups

Follow your doctor’s instructions for regular checkups.

Seek medical advice if you feel unwell

If your symptoms do not improve or worsen, or if new symptoms appear, you should consult your doctor.

Prevention

Ensure balanced nutrition, strengthen physical exercise and enhance resistance.

Avoid going to crowded public places when influenza and other respiratory infections are prevalent.

Avoid contact with people suffering from acute upper respiratory tract infections.

Actively treat underlying diseases

Get vaccinated with influenza vaccine and pneumonia vaccine in winter and spring as appropriate.