The specific criteria for diagnosis of CPA are:

Chest X-rays showing one or more lung cavities. There may be a fungal ball present or not.

Symptoms lasting more than 3 months, usually including weight loss, fatigue, cough, coughing blood (haemoptysis) and breathlessness

A blood test or tissue fluid test positive for Aspergillus species

Aspergilloma

An aspergilloma is a fungal mass caused by a fungal infection with Aspergillus species that grows in either scarred lungs or in a pre-existing lung cavity, which may have been caused by a previous infection. Patients with a previous history of tuberculosis, sarcoidosis, cystic fibrosis or other lung disease are most susceptible to an aspergilloma. Aspergillomas may have no specific symptoms but in many patients there is some coughing up of blood called haemoptysis - this may be infrequent and in small quantity, but can be severe and then it requires urgent medical help.

Tests used to diagnose an aspergilloma may include:

- Chest X-ray

- Chest CT

- Sputum culture

- Bronchoscopy or bronchoscopy with lavage (BAL)

- Serum precipitins for aspergillus (blood test to detect antibodies to aspergillus)

Almost all aspergillomas are caused by "Aspergillus fumigatus". In diabetic patients it may be caused by "Aspergillus niger". It is very rarely caused by "Aspergillus flavus", "Aspergillus oryzae", "Aspergillus terreus" or "Aspergillus nidulans".

Culturing fungi from sputum is a supportive test in the diagnosis of ABPA, but is not 100% specific for ABPA as "A. fumigatus" is ubiquitous and commonly isolated from lung expectorant in other diseases. Nevertheless, between 40–60% of patients do have positive cultures depending on the number of samples taken.

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

New criteria by the ABPA Complicated Asthma ISHAM Working Group suggests a 6-stage criteria for the diagnosis of ABPA, though this is yet to be formalised into official guidelines. This would replace the current gold standard staging protocol devised by Patterson and colleagues. Stage 0 would represent an asymptomatic form of ABPA, with controlled asthma but still fulfilling the fundamental diagnostic requirements of a positive skin test with elevated total IgE (>1000 IU/mL). Stage 6 is an advanced ABPA, with the presence of type II respiratory failure or pulmonary heart disease, with radiological evidence of severe fibrosis consistent with ABPA on a high-resolution CT scan. It must be diagnosed after excluding the other, reversible causes of acute respiratory failure.

Eosinophilic pneumonia is diagnosed in one of three circumstances: when a complete blood count reveals increased eosinophils and a chest x-ray or computed tomography (CT) identifies abnormalities in the lung, when a biopsy identifies increased eosinophils in lung tissue, or when increased eosinophils are found in fluid obtained by a bronchoscopy (bronchoalveolar lavage [BAL] fluid). Association with medication or cancer is usually apparent after review of a person's medical history. Specific parasitic infections are diagnosed after examining a person's exposure to common parasites and performing laboratory tests to look for likely causes. If no underlying cause is found, a diagnosis of AEP or CEP is made based upon the following criteria. AEP is most likely with respiratory failure after an acute febrile illness of usually less than one week, changes in multiple areas and fluid in the area surrounding the lungs on a chest x-ray, and greater than 25% eosinophils on a BAL. Other typical laboratory abnormalities include an elevated white blood cell count, erythrocyte sedimentation rate, and immunoglobulin G level. Pulmonary function testing usually reveals a restrictive process with reduced diffusion capacity for carbon monoxide. CEP is most likely when the symptoms have been present for more than a month. Laboratory tests typical of CEP include increased blood eosinophils, a high erythrocyte sedimentation rate, iron deficiency anemia, and increased platelets. A chest x-ray can show abnormalities anywhere, but the most specific finding is increased shadow in the periphery of the lung, away from the heart.

On chest X-ray and CT, pulmonary aspergillosis classically manifests as a halo sign, and, later, an air crescent sign.

In hematologic patients with invasive aspergillosis, the galactomannan test can make the diagnosis in a noninvasive way. False positive "Aspergillus" galactomannan tests have been found in patients on intravenous treatment with some antibiotics or fluids containing gluconate or citric acid such as some transfusion platelets, parenteral nutrition or PlasmaLyte.

On microscopy, "Aspergillus" species are reliably demonstrated by silver stains, e.g., Gridley stain or Gomori methenamine-silver. These give the fungal walls a gray-black colour. The hyphae of "Aspergillus" species range in diameter from 2.5 to 4.5 µm. They have septate hyphae, but these are not always apparent, and in such cases they may be mistaken for Zygomycota. "Aspergillus" hyphae tend to have dichotomous branching that is progressive and primarily at acute angles of about 45°.

Fungal pneumonia can be diagnosed in a number of ways. The simplest and cheapest method is to culture the fungus from a patient's respiratory fluids. However, such tests are not only insensitive but take time to develop which is a major drawback because studies have shown that slow diagnosis of fungal pneumonia is linked to high mortality. Microscopy is another method but is also slow and imprecise. Supplementing these classical methods is the detection of antigens. This technique is significantly faster but can be less sensitive and specific than the classical methods.

A molecular test based on quantitative PCR is also available from Myconostica. Relying on DNA detection, this is the most sensitive and specific test available for fungi but it is limited to detecting only pneumocystis jirovecii and aspergillus.

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.

Patients with single aspergillomas generally do well with surgery to remove the aspergilloma, and are best given pre-and post-operative antifungal drugs. Often, no treatment is necessary. However, if a patient coughs up blood (haemoptysis), treatment may be required (usually angiography and embolisation, surgery or taking tranexamic acid). Angiography (injection of dye into the blood vessels) may be used to find the site of bleeding which may be stopped by shooting tiny pellets into the bleeding vessel.

For chronic cavitary pulmonary aspergillosis and chronic fibrosing pulmonary aspergillosis, lifelong use of antifungal drugs is usual. Itraconazole and voriconazole are first and second-line anti fungal agents respectively. Posaconazole can be used as third-line agent, for patients who are intolerant of or developed resistance to the first and second-line agents. Regular chest X-rays, serological and mycological parameters as well as quality of life questionnaires are used to monitor treatment progress. It is important to monitor the blood levels of antifungals to ensure optimal dosing as individuals vary in their absorption levels of these drugs.

Eosinophilic pneumonia due to cancer or parasitic infection carries a prognosis related to the underlying illness. AEP and CEP, however, have very little associated mortality as long as intensive care is available and treatment with corticosteroids is given. CEP often relapses when prednisone is discontinued; therefore, some people with CEP require lifelong therapy. Chronic prednisone is associated with many side effects, including increased infections, weakened bones, stomach ulcers, and changes in appearance.

The diagnosis of plastic bronchitis is confirmed by recovery of casts that have been coughed up or visualized during a bronchoscopy. There is no specific cytologic, pathologic or laboratory test that is diagnostic for casts due to lymphatic PB.

Simple chest roentenograms may reveal collapse due to airway obstruction. The contralateral lung may be hyperinflated. Casts can be visualized within the major airways using computerized axial tomography scans.

Heavy T2-weighted MRI, and, as appropriate, intranodal lymphangiogram and/or dynamic contrast-enhanced MR lymphangiography may be useful for identifying pathological lymphatic tissue and/or lymphatic flow.

Bronchiectasis may be diagnosed clinically or on review of imaging. The British Thoracic Society recommends all non-cystic-fibrosis-related bronchiectasis be confirmed by CT. CT may reveal tree-in-bud abnormalities, dilated bronchi, and cysts with defined borders.

Other investigations typically performed at diagnosis include blood tests, sputum cultures, and sometimes tests for specific genetic disorders.

Fungal pneumonia can be treated with antifungal drugs and sometimes by surgical debridement.

Pulmonary ultrasound, performed at the bedside or on the accident scene, is being explored as a diagnosis for pulmonary contusion. Its use is still not widespread, being limited to facilities which are comfortable with its use for other applications, like pneumothorax, airway management, and hemothorax. Accuracy has been found to be comparable to CT scanning.

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.

The current medical treatments for aggressive invasive aspergillosis include voriconazole and liposomal amphotericin B in combination with surgical debridement.

For the less aggressive allergic bronchopulmonary aspergillosis findings suggest the use of oral steroids for a prolonged period of time, preferably for 6–9 months in allergic aspergillosis of the lungs. Itraconazole is given with the steroids, as it is considered to have a "steroid sparing" effect, causing the steroids to be more effective, allowing a lower dose.,

Other drugs used, such as amphotericin B, caspofungin (in combination therapy only), flucytosine (in combination therapy only), or itraconazole,

are used to treat this fungal infection. However, a growing proportion of infections are resistant to the triazoles. "A. fumigatus", the most commonly infecting species, is intrinsically resistant to fluconazole.

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)

Computed tomography (CT scanning) is a more sensitive test for pulmonary contusion, and it can identify abdominal, chest, or other injuries that accompany the contusion. In one study, chest X-ray detected pulmonary contusions in 16.3% of people with serious blunt trauma, while CT detected them in 31.2% of the same people. Unlike X-ray, CT scanning can detect the contusion almost immediately after the injury. However, in both X-ray and CT a contusion may become more visible over the first 24–48 hours after trauma as bleeding and edema into lung tissues progress. CT scanning also helps determine the size of a contusion, which is useful in determining whether a patient needs mechanical ventilation; a larger volume of contused lung on CT scan is associated with an increased likelihood that ventilation will be needed. CT scans also help differentiate between contusion and pulmonary hematoma, which may be difficult to tell apart otherwise. However, pulmonary contusions that are visible on CT but not chest X-ray are usually not severe enough to affect outcome or treatment.

The PESI and sPESI scoring tools can estimate mortality of patients. The Geneva prediction rules and Wells criteria are used to calculate a pre-test probability of patients to predict who has a pulmonary embolism. These scores are tools to be used with clinical judgment in deciding diagnostic testing and types of therapy. The PESI algorithm comprises 11 routinely available clinical variables. It puts the subjects into one of five classes (I-V), with 30-day mortality ranging from 1.1% to 24.5%. Those in classes I and II are low-risk and those in classes III-V are high-risk.

In order to prevent bronchiectasis, children should be immunized against measles, pertussis, pneumonia, and other acute respiratory infections of childhood. While smoking has not been found to be a direct cause of bronchiectasis, it is certainly an irritant that all patients should avoid in order to prevent the development of infections (such as bronchitis) and further complications.

Treatments to slow down the progression of this chronic disease include keeping bronchial airways clear and secretions weakened through various forms of pneumotherapy. Aggressively treating bronchial infections with antibiotics to prevent the destructive cycle of infection, damage to bronchial tubes, and more infection is also standard treatment. Regular vaccination against pneumonia, influenza and pertussis are generally advised. A healthy body mass index and regular doctor visits may have beneficial effects on the prevention of progressing bronchiectasis. The presence of hypoxemia, hypercapnia, dyspnea level and radiographic extent can greatly affect the mortality rate from this disease.

X-rays can be used to examine the lung tissue, however it can not be used to positively diagnose geotrichosis. X-rays may show cavitation that is located the walls of the lungs tissues. The lung tissue resemble the early signs of tuberculosis. The results of an x-ray examination of pulmonary geotrichosis presents smooth, dense patchy infiltrations and some cavities. Bronchial geotrichosis shows peribronchial thickening with fine mottling may be present on middle or basilar pulmonary fields. Bronchial geotrichosis usually present itself as non-specific diffuse peribronchical infiltration.

Airway obstruction may cause obstructive pneumonitis or post-obstructive pneumonitis.

The most commonly used method to predict clinical probability, the Wells score, is a clinical prediction rule, whose use is complicated by multiple versions being available. In 1995, Philip Steven Wells, initially developed a prediction rule (based on a literature search) to predict the likelihood of PE, based on clinical criteria. The prediction rule was revised in 1998 This prediction rule was further revised when simplified during a validation by Wells "et al." in 2000. In the 2000 publication, Wells proposed two different scoring systems using cutoffs of 2 or 4 with the same prediction rule. In 2001, Wells published results using the more conservative cutoff of 2 to create three categories. An additional version, the "modified extended version", using the more recent cutoff of 2 but including findings from Wells's initial studies were proposed. Most recently, a further study reverted to Wells's earlier use of a cutoff of 4 points to create only two categories.

There are additional prediction rules for PE, such as the Geneva rule. More importantly, the use of "any" rule is associated with reduction in recurrent thromboembolism.

"The Wells score":

- clinically suspected DVT — 3.0 points

- alternative diagnosis is less likely than PE — 3.0 points

- tachycardia (heart rate > 100) — 1.5 points

- immobilization (≥ 3d)/surgery in previous four weeks — 1.5 points

- history of DVT or PE — 1.5 points

- hemoptysis — 1.0 points

- malignancy (with treatment within six months) or palliative — 1.0 points

Traditional interpretation

- Score >6.0 — High (probability 59% based on pooled data)

- Score 2.0 to 6.0 — Moderate (probability 29% based on pooled data)

- Score <2.0 — Low (probability 15% based on pooled data)

Alternative interpretation

- Score > 4 — PE likely. Consider diagnostic imaging.

- Score 4 or less — PE unlikely. Consider D-dimer to rule out PE.

Recommendations for a diagnostic algorithm were published by the PIOPED investigators; however, these recommendations do not reflect research using 64 slice MDCT. These investigators recommended:

- Low clinical probability. If negative D-dimer, PE is excluded. If positive D-dimer, obtain MDCT and based treatment on results.

- Moderate clinical probability. If negative D-dimer, PE is excluded. "However", the authors were not concerned that a negative MDCT with negative D-dimer in this setting has a 5% probability of being false. Presumably, the 5% error rate will fall as 64 slice MDCT is more commonly used. If positive D-dimer, obtain MDCT and based treatment on results.

- High clinical probability. Proceed to MDCT. If positive, treat, if negative, more tests are needed to exclude PE. A D-dimer of less than 750 ug/L does not rule out PE in those who are at high risk.

The chest radiograph may appear relatively normal, even late in the disease, or may suggest hyperinflation only. As the disease progresses, the chest radiograph often demonstrates diffuse, bilateral and symmetric reticulonodular opacities, cysts, bullae or a "honeycomb" (i.e., pseudo fibrotic) appearance. Pleural effusion and pneumothorax may be apparent. Preservation of lung volumes in the presence of increased interstitial markings is a radiographic hallmark of LAM that helps distinguish it from most other interstitial lung diseases, in which alveolar septal and interstitial expansion tend to increase the lung’s elastic recoil properties and decreased lung volumes.