Exogenous lipid pneumonia is rare in the general population, but occupational accidents may not be uncommon in fire performers. Diagnosis is usually made on the basis of history of exposure to hydrocarbon fuels, symptoms, and radiological findings. The radiological findings are nonspecific, and the disease presents with variable patterns and distribution. For this reason, lipoid pneumonia may mimic many other diseases, and the diagnosis is often delayed.

Chest X-rays taken shortly after the accident may or may not be abnormal, but typically over time show infiltrates in the lower lobes of the lungs. High-resolution CT will frequently demonstrate abnormalities, including opacities, pleural effusion, consolidation, or pulmonary nodules. Histopathology of lung biopsy or bronchoalveolar lavage may indicate lipid-laden macrophages. Laboratory results may show highly elevated inflammatory markers.

Respiratory diseases may be investigated by performing one or more of the following tests

- Biopsy of the lung or pleura

- Blood test

- Bronchoscopy

- Chest x-ray

- Computed tomography scan, including high-resolution computed tomography

- Culture of microorganisms from secretions such as sputum

- Ultrasound scanning can be useful to detect fluid such as pleural effusion

- Pulmonary function test

- Ventilation—perfusion scan

Respiratory disease is a common and significant cause of illness and death around the world. In the US, approximately 1 billion "common colds" occur each year. A study found that in 2010, there were approximately 6.8 million emergency department visits for respiratory disorders in the U.S. for patients under the age of 18. In 2012, respiratory conditions were the most frequent reasons for hospital stays among children.

In the UK, approximately 1 in 7 individuals are affected by some form of chronic lung disease, most commonly chronic obstructive pulmonary disease, which includes asthma, chronic bronchitis and emphysema.

Respiratory diseases (including lung cancer) are responsible for over 10% of hospitalizations and over 16% of deaths in Canada.

In 2011, respiratory disease with ventilator support accounted for 93.3% of ICU utilization in the United States.

The course of treatment of fire breather's pneumonia remains controversial. Administration of bronchodilators, corticosteroids, and prophylactic antibiotics to prevent secondary infection, is a common course of treatment. Some studies suggest that steroids may improve outcomes in severely affected individuals, yet these data are only based on a limited number of patients. The use of gastric decontamination to prevent subsequent pulmonary injury from hydrocarbon ingestion is controversial. It may have potential benefit in large (> 30 cc), intentional ingestion of compounds with systemic toxicity.

Prognosis after peak symptoms is typically good, with most patients making a full recovery in weeks to months.

Chest radiography is usually the first test to detect interstitial lung diseases, but the chest radiograph can be normal in up to 10% of patients, especially early on the disease process.

High resolution CT of the chest is the preferred modality, and differs from routine CT of the chest. Conventional (regular) CT chest examines 7–10 mm slices obtained

at 10 mm intervals; high resolution CT examines 1-1.5 mm slices at 10 mm

intervals using a high spatial frequency reconstruction algorithm. The HRCT therefore provides approximately 10 times more resolution than the conventional CT chest, allowing the HRCT to elicit details that cannot otherwise be visualized.

Radiologic appearance alone however is not adequate and should be interpreted in the clinical context, keeping in mind the temporal profile of the disease process.

Interstitial lung diseases can be classified according to radiologic patterns.

Investigation is tailored towards the symptoms and signs. A proper and detailed history looking for the occupational exposures, and for signs of conditions listed above is the first and probably the most important part of the workup in patients with interstitial lung disease. Pulmonary function tests usually show a restrictive defect with decreased diffusion capacity (DLCO).

A lung biopsy is required if the clinical history and imaging are not clearly suggestive of a specific diagnosis or malignancy cannot otherwise be ruled out. In cases where a lung biopsy is indicated, a trans-bronchial biopsy is usually unhelpful, and a surgical lung biopsy is often required.

Diagnosis is typically based on a person's signs and symptoms. The color of the sputum does not indicate if the infection is viral or bacterial. Determining the underlying organism is typically not needed. Other causes of similar symptoms include asthma, pneumonia, bronchiolitis, bronchiectasis, and COPD. A chest X-ray may be useful to detect pneumonia.

Another common sign of bronchitis is a cough which lasts ten days to three weeks. If the cough lasts a month or a year it may be chronic bronchitis. In addition to having a cough a fever may be present. Acute bronchitis is normally caused by a viral infection. Typically these infections are rhinovirus, para influenza, or influenza. No specific testing is normally needed to diagnose acute bronchitis.

Individuals with an obstructive pulmonary disorder such as bronchitis may present with a decreased FEV1 and FEV1/FVC ratio on pulmonary function tests. Unlike other common obstructive disorders such as asthma or emphysema, bronchitis rarely causes a high residual volume (the volume of air remaining in the lungs after a maximal exhalation effort).

There are three key elements to the diagnosis of silicosis. First, the patient history should reveal exposure to sufficient silica dust to cause this illness. Second, chest imaging (usually chest x-ray) that reveals findings consistent with silicosis. Third, there are no underlying illnesses that are more likely to be causing the abnormalities. Physical examination is usually unremarkable unless there is complicated disease. Also, the examination findings are not specific for silicosis. Pulmonary function testing may reveal airflow limitation, restrictive defects, reduced diffusion capacity, mixed defects, or may be normal (especially without complicated disease). Most cases of silicosis do not require tissue biopsy for diagnosis, but this may be necessary in some cases, primarily to exclude other conditions.

For uncomplicated silicosis, chest x-ray will confirm the presence of small ( 1 cm) occurs from coalescence of small opacities, particularly in the upper lung zones. With retraction of the lung tissue, there is compensatory emphysema. Enlargement of the hilum is common with chronic and accelerated silicosis. In about 5–10% of cases, the nodes will calcify circumferentially, producing so-called "eggshell" calcification. This finding is not pathognomonic (diagnostic) of silicosis. In some cases, the pulmonary nodules may also become calcified.

A computed tomography or CT scan can also provide a mode detailed analysis of the lungs, and can reveal cavitation due to concomitant mycobacterial infection.

The best way to prevent silicosis is to identify work-place activities that produce respirable crystalline silica dust and then to eliminate or control the dust ("primary prevention"). Water spray is often used where dust emanates. Dust can also be controlled through dry air filtering.

Following observations on industry workers in Lucknow (India), experiments on rats found that jaggery (a traditional sugar) had a preventive action against silicosis.

Health care professionals are at risk of occupational influenza exposure; during a pandemic influenza, anyone in a close environment is at risk, including those in an office environment.

A chest x-ray is useful to confirm or rule out a pneumothorax, pulmonary edema, or pneumonia. Spiral computed tomography with intravenous radiocontrast is the imaging study of choice to evaluate for pulmonary embolism.

Chemical pneumonitis is inflammation of the lung caused by aspirating or inhaling irritants. It is sometimes called a "chemical pneumonia", though it is not infectious. There are two general types of chemical pneumonitis: acute and chronic.

Irritants capable of causing chemical pneumonitis include vomitus, barium used in gastro-intestinal imaging, chlorine gas (among other pulmonary agents), ingested gasoline or other petroleum distillates, ingested or skin absorbed pesticides, gases from electroplating, smoke and others. It may also be caused by the use of inhalants.

Mendelson's syndrome is a type of chemical pneumonitis.

Mineral oil should not be given internally to young children, pets, or anyone with a cough, hiatus hernia, or nocturnal reflux, because it can cause complications such as lipoid pneumonia. Due to its low density, it is easily aspirated into the lungs, where it cannot be removed by the body. In children, if aspirated, the oil can work to prevent normal breathing, resulting in death of brain cells and permanent paralysis and/or retardation

A number of labs may be helpful in determining the cause of shortness of breath. D-dimer while useful to rule out a pulmonary embolism in those who are at low risk is not of much value if it is positive as it may be positive in a number of conditions that lead to shortness of breath. A low level of brain natriuretic peptide is useful in ruling out congestive heart failure; however, a high level while supportive of the diagnosis could also be due to advanced age, renal failure, acute coronary syndrome, or a large pulmonary embolism.

Given the constant threat of bioterrorist related events, there is an urgent need to develop pulmonary protective and reparative agents that can be used by first responders in a mass casualty setting. Use in such a setting would require administration via a convenient route for e.g. intramuscular via epipens. Other feasible routes of administration could be inhalation and perhaps to a lesser extent oral – swallowing can be difficult in many forms of injury especially if accompanied by secretions or if victim is nauseous. A number of in vitro and in vivo models lend themselves to preclinical evaluation of novel pulmonary therapies.

Pulmonary aspiration resulting in pneumonia, in some patients, particularly those with physical limitations, can be fatal.

Tuberculosis is a lung disease endemic in many parts of the world. Health care professionals and prison guards are at high risk for occupational exposure to tuberculosis, since they work with populations with high rates of the disease.

Acute:

- Cough

- Difficulty Breathing

- Abnormal lung sounds (wet, gurgling sounding breaths)

- Chest pain, tightness or burning

Chronic:

- Persistent cough

- Shortness of breath

- Increased susceptibility to respiratory illness

Symptoms of chronic chemical pneumonitis may or may not be present, and can take months or years to develop to the point of noticeability.

There is ongoing research on the treatment of ARDS by interferon (IFN) beta-1a to aid in preventing leakage of vascular beds. Traumakine (FP-1201-lyo), is a recombinant human IFN beta-1a drug developed by Faron pharmaceuticals, is undergoing international phase-III clinical trials after an open-label, early-phase trial showed a 81% reduction-in-odds of 28-day mortality in ICU patients with ARDS. The drug is known to function by enhancing lung CD73 expression and increasing production of anti-inflammatory adenosine, such that vascular leaking and escalation of inflammation are reduced.

Specific pretreatments, drugs to prevent chemically induced lung injuries due to respiratory airway toxins, are not available. Analgesic medications, oxygen, humidification, and ventilator support currently constitute standard therapy. In fact, mechanical ventilation remains the therapeutic mainstay for acute inhalation injury. The cornerstone of treatment is to keep the PaO2 > 60 mmHg (8.0 kPa), without causing injury to the lungs with excessive O2 or volutrauma. Pressure control ventilation is more versatile than volume control, although breaths should be volume limited, to prevent stretch injury to the alveoli. Positive end-expiratory pressure (PEEP) is used in mechanically ventilated patients with ARDS to improve oxygenation. Hemorrhaging, signifying substantial damage to the lining of the airways and lungs, can occur with exposure to highly corrosive chemicals and may require additional medical interventions. Corticosteroids are sometimes administered, and bronchodilators to treat bronchospasms. Drugs that reduce the inflammatory response, promote healing of tissues, and prevent the onset of pulmonary edema or secondary inflammation may be used following severe injury to prevent chronic scarring and airway narrowing.

Although current treatments can be administered in a controlled hospital setting, many hospitals are ill-suited for a situation involving mass casualties among civilians. Inexpensive positive-pressure devices that can be used easily in a mass casualty situation, and drugs to prevent inflammation and pulmonary edema are needed. Several drugs that have been approved by the FDA for other indications hold promise for treating chemically induced pulmonary edema. These include β2-agonists, dopamine, insulin, allopurinol, and non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen. Ibuprofen is particularly appealing because it has an established safety record and can be easily administered as an initial intervention. Inhaled and systemic forms of β2-agonists used in the treatment of asthma and other commonly used medications, such as insulin, dopamine, and allopurinol have also been effective in reducing pulmonary edema in animal models but require further study. A recent study documented in the "AANA Journal" discussed the use of volatile anesthetic agents, such as sevoflurane, to be used as a bronchodilator that lowered peak airway pressures and improved oxygenation. Other promising drugs in earlier stages of development act at various steps in the complex molecular pathways underlying pulmonary edema. Some of these potential drugs target the inflammatory response or the specific site(s) of injury. Others modulate the activity of ion channels that control fluid transport across lung membranes or target surfactant, a substance that lines the air sacs in the lungs and prevents them from collapsing. Mechanistic information based on toxicology, biochemistry, and physiology may be instrumental in determining new targets for therapy. Mechanistic studies may also aid in the development of new diagnostic approaches. Some chemicals generate metabolic byproducts that could be used for diagnosis, but detection of these byproducts may not be possible until many hours after initial exposure. Additional research must be directed at developing sensitive and specific tests to identify individuals quickly after they have been exposed to varying levels of chemicals toxic to the respiratory tract.

Currently there are no clinically approved agents that can reduce pulmonary and airway cell dropout and avert the transition to pulmonary and /or airway fibrosis.

The lungs are normally protected against aspiration by a series of "protective reflexes" such as coughing and swallowing. Significant aspiration can only occur if the protective reflexes are absent or severely diminished (in neurological disease, coma, drug overdose, sedation or general anesthesia). In intensive care, sitting patients up reduces the risk of pulmonary aspiration and ventilator-associated pneumonia.

Measures to prevent aspiration depend on the situation and the patient. In patients at imminent risk of aspiration, tracheal intubation by a trained health professional provides the best protection. A simpler intervention that can be implemented is to lay the patient on their side in the recovery position (as taught in first aid and CPR classes), so that any vomitus produced by the patient will drain out their mouth instead of back down their pharynx. Some anesthetists will use sodium citrate to neutralize the stomach's low pH and metoclopramide or domperidone (pro-kinetic agents) to empty the stomach.

People with chronic neurological disorders, for example, after a stroke, are less likely to aspirate thickened fluids.

The location of abscesses caused by aspiration depends on the position one is in. If one is sitting or standing up, the aspirate ends up in the posterior basal segment of the right lower lobe. If one is on one's back, it goes to the superior segment of the right lower lobe. If one is lying on the right side, it goes to the posterior segment of the right upper lobe, or the posterior basal segment of the right upper lobe. If one is lying on the left, it goes to the lingula.

Radiologic imaging has long been a criterion for diagnosis of ARDS. While original definitions of ARDS specified that correlative chest X-ray findings were required for diagnosis, the diagnostic criteria have been expanded over time to accept CT and ultrasound findings as equally contributory. Generally, radiographic findings of fluid accumulation (pulmonary edema) affecting both lungs and unrelated to increased cardiopulmonary vascular pressure (such as in heart failure) may be suggestive of ARDS.

Ultrasound findings suggestive of ARDS include the following:

- Anterior subpleural consolidations

- Absence or reduction of lung sliding

- “Spared areas” of normal parenchyma

- Pleural line abnormalities (irregular thickened fragmented pleural line)

- Nonhomogeneous distribution of B-lines (a characteristic ultrasound finding suggestive of fluid accumulation in the lungs)

Lung symptoms in a patient who is taking a medicinal drug that can cause pulmonary toxicity should not automatically lead to a diagnosis of "pulmonary toxicity due to the medicinal drug", because some patients can have another (i.e., simultaneous) lung disease, e.g. an infection of the lungs "not" related to the medicinal drugs the patient is taking. But if the patient is taking such a medicinal drug, this should not be overlooked. Diagnostic care should be executed. The correct diagnosis is an exclusion diagnosis and can require some tests.

Alveolar disease is visible on chest radiography as small, ill-defined nodules of homogeneous density centered on the acini or bronchioles. The nodules coalesce early in the course of disease, such that the nodules may only be seen as soft fluffy edges in the periphery.

When the nodules are centered on the hilar regions, the chest x-ray may develop what is called the "butterfly," or "batwing" appearance. The nodules may also have a segmental or lobar distribution. Air alveolograms and air bronchograms can also be seen.

These findings appear soon after the onset of symptoms and change rapidly thereafter.

A segmental or lobar pattern may be apparent after aspiration pneumonia, atelectasis, lung contusion, localized pulmonary edema, obstructive pneumonia, pneumonia, pulmonary embolism with infarction, or tuberculosis.

Side effects on the lungs can be very varied, and can include signs and symptoms that are either clinical, or radiological (i.e., seen on chest X-ray or CT), or both. They can include lung inflammation (pneumonitis), secondary (in this context, indirectly caused) lung infection (pneumonia), lung fibrosis, organising pneumonia (bronchiolitis obliterans organising pneumonia, BOOP), ARDS (acute respiratory distress syndrome), solitary pulmonary mass (even including lung cancer in some cases, mainly in cases of asbestos-related lung disease, but today this is very rare, because asbestos is now completely prohibited by law in most countries), or pulmonary nodule. The diagnosis should be made by a specialist, if possible.