Ground glass nodules (GGN) are an imaging sign that refers to increased density in the lungs with clear or unclear boundaries shown on CT, but the density of the lesions is not enough to cover the blood vessels and bronchial shadows running in them. In most cases, ground glass nodules are discovered accidentally during routine physical examinations or diagnosis and treatment of other diseases. Most patients may not have obvious symptoms, but in the case of symptoms, common manifestations include dyspnea, chest pain, cough or hemoptysis. The causes of ground glass nodules are diverse and may be caused by infection, inflammation, benign lesions or malignant tumors. Confirmation and differential diagnosis usually rely on detailed medical imaging examinations and clinical evaluation.
Epidemiology
Epidemiology
With the widespread use of high-resolution imaging examinations such as chest CT scans, the detection rate of ground-glass nodules has increased, but there is no exact incidence data.
Infectious
Certain infectious factors, such as ground-glass nodules caused by Mycobacterium tuberculosis infection, are contagious.
Source of infection
The mycobacterium tuberculosis that causes illness in humans mainly comes from infected people and animals (mainly cattle) that are infected with mycobacterium tuberculosis and excrete the bacteria. Among them, the main source of infection is patients with open pulmonary tuberculosis who excrete the bacteria.
Mode of transmission
1. Respiratory transmission
Respiratory transmission is the most important route of transmission of Mycobacterium tuberculosis infection. People infected with Mycobacterium tuberculosis expel the tuberculosis bacilli suspended in droplet nuclei and spread through coughing, sneezing, laughing, etc., which can cause infection if inhaled by healthy people.
2. Transmission through other routes such as the digestive tract and skin
Such as drinking contaminated milk, mother-to-child transmission by sick pregnant women, and skin wound infection, but this type of transmission is now relatively rare.
Incidence
There is no exact incidence data yet.
Prone population
1. People who are exposed to high-risk occupations, such as workers in chemical plants, dust factories, and disinfection workers.
2. Those with fungal or bacterial lung infection and related medical history.
3. Those who smoke or have a history of smoking.
symptom
Classification
1. Classification based on ground glass nodule density
(1) Pure ground glass nodules
Pure ground glass nodules refer to blurred nodular shadows in the lungs. The density of the nodules is slightly higher than that of the surrounding lung parenchyma, but the outlines of the blood vessels and bronchi inside them are still visible.
(2) Partially solid nodules
Partially solid nodules refer to nodules that contain both pure ground glass density and solid soft tissue density, and the density is uneven.
2. Classification of benign and malignant ground glass nodules
It can be divided into benign ground glass nodules and malignant ground glass nodules. Malignant ground glass nodules are relatively hidden in the early stages. If not intervened early, the disease will progress rapidly, be highly malignant, and have a poor prognosis.
Typical manifestations
1. Cough
When ground-glass nodules affect the pulmonary nerves, persistent and recurrent coughing may occur. Ground-glass nodules caused by infection are often accompanied by purulent sputum.
2. Chest pain
When tumors or tuberculosis lesions involve the pleura or chest wall, chest pain may occur, which worsens with respiratory movement and coughing.
3. Difficulty breathing
If the ground glass nodules continue to grow larger and compress the large bronchi, symptoms such as chest tightness, shortness of breath, wheezing, and difficulty breathing may occur.
4. Hemoptysis
When ground-glass nodules invade the pulmonary vessels, patients may experience hemoptysis.
5. Systemic manifestations
For ground-glass nodules caused by malignant tumors or tuberculosis infection, nonspecific manifestations may occur, such as fatigue, low-grade fever, weight loss, and night sweats (sweating during sleep at night, which stops after waking up). If the tuberculosis lesions progress and spread rapidly, high fever may occur.
complication
There are generally no obvious complications.
reason
Overview
There are many causes of ground-glass nodules, which can be divided into benign pulmonary nodules and malignant pulmonary nodules according to their benign or malignant nature. Among malignant pulmonary nodules, most are primary lung cancers, with adenocarcinoma being the most common, followed by squamous cell carcinoma. Benign nodules have many causes, which can be caused by benign tumors, infections, or inflammatory, vascular or congenital lesions.
Cause of symptoms
1. Basic cause
(1) Malignant lesions
①Primary lung cancer: mainly includes lung adenocarcinoma, lung squamous cell carcinoma, lung large cell carcinoma, and lung small cell carcinoma.
② Metastatic malignant tumors: such as head and neck malignant tumors, melanoma, colon cancer, etc.
(2) Benign lesions
① Benign tumors: such as pulmonary hamartoma, pulmonary fibroma, pulmonary lipoma, etc.
② Infection: Mycobacterium tuberculosis infection, pulmonary fungal infection (such as Candida, Aspergillus, Mucor), etc.
③Inflammatory lesions: such as granulomatosis, sarcoidosis, etc.
④ Pulmonary vascular abnormalities: such as pulmonary arteriovenous malformations, pulmonary capillary dilatation, etc.
⑤ Congenital lung diseases: such as bronchial cysts, pulmonary sequestration, etc.
2. High-risk factors
(1) Smoking or having a history of smoking.
(2) Presence of fungal or bacterial lung infection.
(3) Patients with a history of malignant tumors or a family history of lung cancer.
(4) Have a history of environmental or high-risk occupational exposure, such as frequent contact with asbestos, beryllium, uranium, radon, etc.
(5) Combined with chronic obstructive pulmonary disease and diffuse pulmonary fibrosis.
Common diseases
Lung adenocarcinoma, squamous cell carcinoma, large cell carcinoma, small cell carcinoma, melanoma, colon cancer, pulmonary hamartoma, pulmonary fibrosis, pulmonary lipoma, Mycobacterium tuberculosis infection, pulmonary fungal infection, granulomatous disease, sarcoidosis, pulmonary arteriovenous malformation, pulmonary telangiectasia, bronchial cyst, pulmonary sequestration
Medical treatment
Emergency (120) Indications
1. Severe breathing difficulties occur and persist.
2. Sudden high fever.
3. Other critical symptoms occur.
All of the above require prompt emergency treatment and call the emergency number if necessary.
Outpatient Indications
1. Chest CT shows increased density in the lungs with clear or unclear boundaries, but the density of the lesions is not enough to cover the blood vessels and bronchial shadows running through them.
2. Accompanied by repeated chest tightness, shortness of breath, and wheezing.
3. Accompanied by persistent and recurrent cough and sputum.
4. Accompanied by coughing up a small amount of blood.
5. Accompanied by unexplained chest pain, which worsens with respiratory movement and coughing.
6. Accompanied by rapid weight loss, low fever, and night sweats.
7. Other severe, persistent or progressive symptoms and signs occur.
All of the above require prompt medical consultation.
Department
1. If the situation is critical or the symptoms are severe, please go to the emergency department immediately.
2. For patients whose condition is stable but who experience respiratory symptoms such as wheezing and coughing, they should see a respiratory physician.
3. Depending on the cause and specific treatment, you may also need to visit the oncology department or thoracic surgery department.
Medical preparation
1. Make an appointment in advance and bring your ID card, medical insurance card, medical card, etc.
2. Most patients need to undergo imaging examinations and should wear loose clothing without metal accessories.
3. The patient may need to be hospitalized for observation, and family members can make relevant preparations in advance.
4. If you have had medical treatment recently, please bring relevant medical records, examination reports, test results, etc.
5. If you have taken some medicine to relieve symptoms recently, you can carry the medicine box.
6. Arrange for family members to accompany the patient to seek medical treatment whenever possible.
7. Patients can prepare a list of questions they want to ask in advance.
Questions your doctor may ask you
1. Do you have symptoms of coughing, expectoration, or chest pain? When did they occur?
2. Have your symptoms worsened recently?
3. Have you lost weight recently? Do you have a fever?
4. Do you have any other symptoms?
5. Have you ever had tuberculosis?
6. Have you ever had a malignant tumor? What treatment did you receive?
7. Do you have a family history of lung cancer?
8. What do you do for a living?
9. Do you smoke? How many cigarettes do you smoke a day?
Questions patients can ask their doctors
1. Why do I have these symptoms? Is there a clear diagnosis now?
2. What tests do I need to take? Are these tests covered by medical insurance?
3. Is my condition serious? Do I need to be hospitalized?
4. What treatment do I need? Are there any risks during the treatment?
5. How long does it take to treat? Can it be cured? Will it recur after being cured?
6. What should I pay attention to in my daily life?
7. Do I need follow-up examinations? How often?
examine
Estimated inspection
The doctor will perform a physical examination on the patient to understand the basic condition of the lungs and the whole body. After that, imaging examinations such as high-resolution computed tomography and positron emission tomography will be performed to clarify the characteristics of the lung nodules. When a malignant tumor is suspected, a surgical or non-surgical pathological biopsy may be required, and sometimes a tumor marker test is required to assist in the diagnosis.
Physical examination
Doctors mainly perform lung percussion, auscultation and superficial lymph node examination on patients to help make a preliminary diagnosis of the condition.
Laboratory tests
1. Tumor marker detection
Patients with ground glass nodules can undergo tumor marker testing when necessary, which can provide a certain reference for the diagnosis and differential diagnosis of ground glass nodules.
2. Tuberculin skin test
Doctors inject tuberculin antigen into the patient’s skin and observe local reactions. If the injection site is red or swollen, it indicates that the ground-glass nodules may be caused by pulmonary tuberculosis.
Imaging tests
1. High-resolution computed tomography (HRCT)
HRCT can clearly show the size, shape, boundary and presence of solid components of ground glass nodules. In addition, HRCT can also help evaluate the changes of nodules over time, such as increase or decrease in size and structural changes.
2. Positron emission tomography (PET-CT)
PET-CT is of certain value in determining active lesions in the patient’s body, helping to judge the benign or malignant nature of nodules, and can also provide important basis for selecting puncture biopsy sites.
Pathological examination
In order to more accurately determine the nature of the nodule, the doctor may use bronchoscopy, thoracoscopy, mediastinoscopy or transthoracic lung puncture to obtain tissue samples for pathological examination.
diagnosis
Diagnostic principles
Doctors can make a preliminary diagnosis based on the patient’s clinical manifestations and imaging examination results. Combined with medical history (such as occupational exposure history, smoking history, chronic lung disease history, personal and family history of tumors, etc.), biopsy, and related laboratory tests, the nature of the nodules can be evaluated and the cause can be determined. During the diagnosis process, it is necessary to identify common diseases that cause ground-glass nodules, such as lung cancer, pulmonary hamartoma, pulmonary sarcoidosis, and pulmonary tuberculosis.
Diagnosis
1. Benign nodules
During follow-up, pulmonary nodules with the following changes are generally considered to be benign:
(1) The external features of the lesion change significantly in a short period of time, with no lobulation or extremely deep lobulation, and the edges becoming smooth or blurred;
(2) The density is uniform or becomes lighter;
(3) The lesion shrinks or disappears without increasing in density;
(4) The lesions grow rapidly, with a doubling time of <15 days;
(5) Solid nodular lesions remain stable for more than 2 years. However, this feature does not apply to ground-glass nodules, because ground-glass nodules in the adenocarcinoma in situ and microinvasive adenocarcinoma stages can be stable for a long time. The long term here refers to more than 2 years or longer, but how long the stability indicates benignity still needs further study.
2. Malignant nodules
When a pulmonary nodule shows the following changes during follow-up, it is often considered to be malignant:
(1) The diameter increase and doubling time are consistent with the growth law of tumor;
(2) The lesion is stable or enlarged, and physical components appear;
(3) The lesion is reduced in size, but the solid component appears or increases in size;
(4) Angiogenesis conforms to the law of lung cancer;
(5) The presence of lobulation, spiculation, and/or pleural indentation signs.
Differential Diagnosis
1. Lung cancer
Cough is an early symptom, often an irritating dry cough with little or no sputum. Coughing may worsen when the tumor causes bronchial stenosis. Lung cancer patients may also experience symptoms such as blood in sputum or hemoptysis, shortness of breath or wheezing, chest pain, fever, and weight loss. Chest X-ray is one of the most commonly used methods for detecting lung cancer, but it has low resolution and is not easy to detect tiny lung nodules and lesions in hidden parts, which has certain limitations in the detection of early lung cancer. Chest computed tomography (CT) has a higher resolution and can detect tiny lung lesions and areas that are difficult to display on ordinary chest X-rays (such as those behind the heart, beside the spine, at the apex of the lungs, at the costophrenic angle, and at the rib heads). Enhanced CT can sensitively detect enlarged hilar and mediastinal lymph nodes, which helps in the clinical staging of lung cancer.
2. Pulmonary Hamartoma
Most patients have no symptoms, while those with symptoms often present with cough, sputum, shortness of breath, chest pain, fever, etc. Chest X-rays show that the tumor tissue is round or oval, with complete and smooth edges, and often with calcification points.
3. Pulmonary sarcoidosis
Symptoms include fever, fatigue, weight loss, joint pain, chest pain, cough, dyspnea, hemoptysis, etc. Chest X-ray is a sensitive tool for diagnosis, and bilateral hilar lymphadenopathy is the most common sign. High-resolution CT (HRCT) of the chest typically shows tiny nodules distributed along the bronchovascular bundles, which can fuse into balls. Other abnormalities include ground-glass opacity, cord-band shadows, honeycomb lungs, tractional bronchiectasis, and distortion or deformation of blood vessels or bronchi.
4. Tuberculosis
Coughing and expectoration for more than two weeks or blood in the sputum are common suspicious symptoms of pulmonary tuberculosis. About 1/3 of patients have hemoptysis, most patients have small amounts of hemoptysis, and a few have large hemoptysis. When tuberculosis lesions involve the pleura, chest pain may occur, which worsens with respiratory movement and coughing. Fever is the most common systemic toxic symptom, which is mostly long-term afternoon hot flashes, that is, it starts to rise in the afternoon or evening and returns to normal in the early morning of the next day. Some patients have fatigue, night sweats, loss of appetite and weight loss. Female patients of childbearing age may have irregular menstruation. Chest X-ray and CT examinations can reveal lesions of various shapes in the lungs, with uneven density, clear edges, and slow changes in lesions.
treat
Expected treatment
Doctors will give individualized treatment plans based on the cause of ground-glass nodules. If ground-glass nodules are diagnosed as malignant tumors, surgical resection can be considered; for those caused by Mycobacterium tuberculosis infection or fungal infection, anti-tuberculosis and anti-fungal treatments are given respectively. If the ground-glass nodules cannot be qualitatively identified, doctors will formulate appropriate follow-up plans based on the probability of malignancy of the nodules to observe changes in the nodules.
Drug treatment
1. Anti-tuberculosis drugs
It is mainly used for ground glass nodules caused by pulmonary tuberculosis. Commonly used drugs include isoniazid and rifampicin, which can kill tuberculosis bacteria and achieve the purpose of controlling the disease.
2. Antibiotics
Commonly used drugs include ofloxacin, norfloxacin, moxifloxacin, erythromycin, etc. It is mainly used for patients with infection symptoms and can prevent secondary infection.
3. Antifungal drugs
It is mainly used for patients with fungal infections. Commonly used drugs include itraconazole, fluconazole, terbinafine hydrochloride, etc.
Related drugs
Isoniazid, rifampicin, ofloxacin, norfloxacin, moxifloxacin, erythromycin, itraconazole, fluconazole, terbinafine hydrochloride
Surgery
1. Surgical method
(1) Video-assisted thoracoscopic surgery (VATS)
The doctor will make a tiny incision in the patient’s chest and insert a tube with a camera and light source for surgery. It has the characteristics of wide field of view, small trauma, light pain, and fast postoperative recovery. At the same time, it can clear more mediastinal lymph nodes and reduce the incidence of residual lymph nodes. It is currently the main surgical method.
(2) Thoracotomy
For deeper nodules, open-chest surgery may be necessary.
2. Surgical resection range
Doctors will perform sublobar or lobectomy, wedge resection, segmental or subsegmental resection, and regional lymph node dissection depending on the size and nature of the nodule.
Other treatments
For ground-glass nodules with a high probability of malignancy that cannot tolerate surgery, ablation therapy can be considered after PET evaluation.
Treatment cycle
The treatment cycle is affected by factors such as the severity of the disease, treatment plan, timing of treatment, age and physical condition, and may vary from individual to individual.
Estimated cost of treatment
There may be significant individual differences in treatment costs, and the specific costs are related to the selected hospital, treatment plan, medical insurance policy, etc.
Prognosis
General Prognosis
Most benign ground-glass nodules and infectious ground-glass nodules have a good prognosis after timely, reasonable and standardized treatment; however, if the treatment is not timely, it is easy to cause lung function damage. If malignant ground-glass nodules (such as lung cancer) are diagnosed and treated in time, they can improve the quality of life, prolong the survival period, and even achieve clinical cure to a certain extent.
Hazards
1. If ground glass nodules are not effectively controlled, they may cause damage to lung function.
2. Ground glass nodules may be malignant and may be life-threatening if not effectively treated.
3. Ground glass nodules caused by infection, pathogens can reach all parts of the body through the blood, leading to the formation of local or systemic abscesses.
4. Malignant ground glass nodules may metastasize. Metastasis to the central nervous system may cause symptoms of weakness in one side of the limbs or even hemiplegia.
Self-healing
It usually does not heal on its own.
Curative
1. Ground glass nodules caused by infection can be cured in most patients through active anti-infection treatment; for some tuberculosis patients, ground glass nodules cannot be completely absorbed after regular treatment, and eventually calcification foci are formed.
2. Nodules caused by benign lung tumors can be cured through surgical resection.
3. Ground glass nodules with a higher degree of malignancy can be clinically cured through early surgical treatment and, if necessary, postoperative radiotherapy and chemotherapy.
Recurrent
There is also a certain risk of recurrence after surgery.
daily
Nursing principles
Patients with ground glass nodules may have respiratory symptoms, so in order to maintain a good condition, stabilize the condition, and promote recovery, it is particularly important to adjust daily lifestyle and environmental management.
Psychological care
1. Psychological characteristics
(1) After being diagnosed with ground glass nodules, some patients may experience panic, anxiety, and other symptoms.
(2) Some patients with ground-glass nodules have more obvious symptoms, which are mainly concentrated in the respiratory system. Coughing and wheezing can cause great discomfort to patients. In addition, the long course of the disease may bring a greater psychological burden to patients.
2. Nursing points
(1) Patients can take the initiative to learn relevant medical knowledge about ground glass nodules, maintain a good attitude, actively communicate with relatives and friends, enhance their confidence in overcoming the disease, and actively cooperate with treatment.
(2) In daily life, family members should take the initiative to communicate with patients, understand their true feelings, provide them with sufficient encouragement and support, give them more respect, understanding and love, and let them feel the warmth of family affection.
(3) Patients can develop a wide range of hobbies, such as practicing calligraphy, listening to music, and painting watercolors, to divert their attention. At the same time, they can communicate and exchange with other patients with the same disease and encourage each other.
Medication care
After discovering ground glass nodules, do not blindly take medication on your own, but take medication under the guidance of a doctor. During medication, pay attention to whether nausea, vomiting, allergies and other adverse reactions occur, and seek medical treatment if necessary.
Postoperative Care
1. After the patient is pushed into the ward, family members should help the patient to tilt his head to one side, and after waking up, lie on the healthy side.
2. After waking up from anesthesia, family members can help the patient move his arms, shoulders, and lower limbs.
3. Get out of bed and move around early after surgery, and gradually start exercise to promote recovery of cardiopulmonary function.
4. After the operation, you should eat a light diet and supplement with protein-rich foods appropriately.
Life Management
1. When you have difficulty breathing, you can adopt a semi-sitting position or a lying position with a high pillow to avoid airway compression and aggravating breathing difficulties.
2. Patients with sputum should cough it out in time to avoid swallowing sputum which may worsen the infection.
3. Do proper exercise to enhance physical fitness and promote recovery from illness.
4. The indoor air should be kept fresh and ventilated, but avoid direct wind that may cause colds.
5. Ensure adequate sleep and a regular schedule.
Follow-up consultation instructions
If the cause of ground glass nodules is unknown and surgery is not needed temporarily, patients can go to the hospital for a follow-up visit every 3 months, mainly for lung X-ray, CT and other imaging examinations; for patients who undergo surgery, they need to follow the doctor’s instructions for regular follow-up after surgery so that the doctor can determine whether the nodules have disappeared or reappeared. The Chinese Expert Consensus on the Diagnosis and Treatment of Pulmonary Nodules (2018 Edition) recommends that patients follow the doctor’s instructions and follow up on time so that the doctor can observe the condition of the lung nodules. The specific contents are as follows:
1. Solitary pure ground glass nodule
(1) If a single pure ground glass nodule is ≤5 mm, a follow-up chest CT is recommended within 6 months, followed by annual follow-up chest CT.
(2) If a single pure ground glass nodule is larger than 5 mm, a follow-up chest CT scan is recommended every 3 months. If there is no change, routine annual follow-up is recommended.
2. Solitary partially solid nodules
(1) If a single partially solid nodule is ≤8 mm, CT follow-up is recommended at 3, 6, 12, and 24 months. If there is no change, routine annual examination is then recommended.
(2) If a single partially solid nodule is larger than 8 mm, a chest CT scan is recommended every 3 months. If the nodule persists, PET, nonsurgical biopsy, and/or surgical resection are recommended for further evaluation.
diet
Diet
Patients with ground glass nodules should develop healthy eating habits. Their daily diet should be light, nutritious and easy to digest. This is of great significance for the stability and recovery of the patient’s condition.
Dietary advice
1. It is advisable to eat light and easily digestible food.
2. Eat more fresh vegetables and fruits, such as watermelon, citrus, pears, etc.
3. You can eat high-protein foods appropriately, such as eggs, milk, chicken, fish, shrimp, etc.
Dietary taboos
1. Avoid eating greasy and spicy foods.
2. Avoid eating seafood and river food, such as crabs, shrimps, hairtail, yellow croaker, etc.
3. Avoid smoking, drinking, coffee, cold drinks, etc.
prevention
Precautions
There is no definite and effective way to prevent ground glass nodules. However, measures such as quitting smoking, avoiding exposure to harmful substances, keeping indoor air fresh, and regular checkups can help reduce the risk of ground glass nodules.
1. Quit smoking
Harmful chemicals in tobacco smoke can cause lung inflammation and tissue damage, increasing the risk of ground-glass nodules. Therefore, quitting smoking is an important measure to prevent ground-glass nodules and other lung diseases.
2. Avoid contact with harmful substances
Chemicals, asbestos, radioactive materials, and other hazardous substances may increase the risk of ground glass nodules and lung cancer. Avoiding exposure to these substances in the work and living environment is the key to reducing the risk. If you are unavoidably exposed to these substances at work, you should use appropriate protective equipment.
3. Keep the indoor air fresh
Air pollutants, including indoor air pollution, may also increase the risk of ground-glass nodules. Maintaining good indoor ventilation, using air purifiers, and reducing the accumulation of smoke and dust indoors can help reduce this risk.
4. Regular inspection
Regular lung imaging tests, especially for people with risk factors for ground-glass nodules, such as long-term smokers, can help detect problems early.