Aspergillosis is an infection caused by the fungus "Aspergillus". Aspergillosis describes a large number of diseases involving both infection and growth of fungus as well as allergic responses. Aspergillosis can occur in a variety of organs, both in humans and animals.

The most common sites of infection are the respiratory apparatus (lungs, sinuses) and these infections can be:

- Invasive (e.g. – IPA)

- Non-invasive (e.g. Allergic Pulmonary Aspergillosis - ABPA)

- Chronic pulmonary and aspergilloma (e.g. chronic cavitary, semi-invasive)

- Severe asthma with fungal sensitisation (SAFS)

Chronic pulmonary aspergillosis (CPA) is a long-term aspergillus infection of the lung and "Aspergillus fumigatus" is almost always the species responsible for this illness. Patients fall into several groups as listed below.

- Those with an aspergilloma which is a ball of fungus found in a single lung cavity - which may improve or disappear, or change very little over a few years.

- Aspergillus nodule

- Chronic cavitary pulmonary aspergillosis (CCPA) where cavities are present in the lungs, but not necessarily with a fungal ball (aspergilloma).

- Chronic fibrosing pulmonary aspergillosis this may develop where pulmonary aspergillosis remains untreated and chronic scarring of the lungs occurs. Unfortunately scarring of the lungs does not improve.

Most patients with CPA have or have had an underlying lung disease. The most common diseases include tuberculosis, atypical mycobacterium infection, stage III fibrocystic pulmonary sarcoidosis, ABPA, lung cancer, COPD and emphysema, asthma and silicosis.

A fungus ball in the lungs may cause no symptoms and may be discovered only with a chest X-ray, or it may cause repeated coughing up of blood, chest pain, and occasionally severe, even fatal, bleeding. A rapidly invasive "Aspergillus" infection in the lungs often causes cough, fever, chest pain, and difficulty breathing.

Poorly controlled aspergillosis can disseminate through the blood stream to cause widespread organ damage. Symptoms include fever, chills, shock, delirium, seizures and blood clots. The person may develop kidney failure, liver failure (causing jaundice), and breathing difficulties. Death can occur quickly.

Aspergillosis of the ear canal causes itching and occasionally pain. Fluid draining overnight from the ear may leave a stain on the pillow. Aspergillosis of the sinuses causes a feeling of congestion and sometimes pain or discharge. It can extend beyond the sinuses.

In addition to the symptoms, an X-ray or computerised tomography (CT) scan of the infected area provides clues for making the diagnosis. Whenever possible, a doctor sends a sample of infected material to a laboratory to confirm identification of the fungus.

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".

Most types of eosinophilic pneumonia have similar signs and symptoms. Prominent and nearly universal signs and symptoms include cough, fever, difficulty breathing, and night sweats. Acute eosinophilic pneumonia typically follows a rapid course. Fever and cough may develop only one or two weeks before breathing difficulties progress to the point of respiratory failure requiring mechanical ventilation. Chronic eosinophilic pneumonia usually follows a slower course. Symptoms accumulate over several months and include fever, cough, difficulty breathing, wheezing, and weight loss. Individuals with CEP are often misdiagnosed with asthma before CEP is finally recognized.

EP due to medications or environmental exposures is similar and occurs after an exposure to a known offending agent. EP due to parasitic infections has a similar prodrome in addition to a host of different symptoms related to the variety of underlying parasites. EP in the setting of cancer often develops in the context of a known diagnosis of lung cancer, cervical cancer, etc.

Almost all patients have clinically diagnosed asthma, and present with wheezing (usually episodic in nature), coughing, shortness of breath and exercise intolerance (especially in patients with cystic fibrosis). Moderate and severe cases have symptoms suggestive of bronchiectasis, in particular thick sputum production (often containing brown mucus plugs), as well as symptoms mirroring recurrent infection such as pleuritic chest pain and fever. Patients with asthma and symptoms of ongoing infection, who do not respond to antibiotic treatment, should be suspected of ABPA.

The clinical presentation of plastic bronchitis beyond expectoration of casts includes a productive cough, dyspnea, fever and wheezing. Focal wheezing is a characteristic, if not specific, physical examination finding. If the casts completely obstruct the airway, breath sounds will be decreased and dullness will be present with percussion. With partial obstruction, a “fan sound” or “flag flapping” sound can be heard during auscultation. Bronchial casts can sometimes fill the airways of almost an entire lung, and present as an acute, life-threatening emergency.

Eosinophilic pneumonia is divided into different categories depending upon whether a cause can be determined or not. Known causes include certain medications or environmental triggers, parasitic infections, and cancer. EP can also occur when the immune system attacks the lungs, a disease called eosinophilic granulomatosis with polyangiitis. When a cause cannot be found, the EP is labeled "idiopathic." Idiopathic EP can be divided into "acute eosinophilic pneumonia" (AEP) and "chronic eosinophilic pneumonia" (CEP) depending on the symptoms a person is experiencing.

Aspergillosis is the name given to a wide variety of diseases caused by infection by fungi of the genus "Aspergillus". The majority of cases occur in people with underlying illnesses such as tuberculosis or chronic obstructive pulmonary disease (COPD), but with otherwise healthy immune systems. Most commonly, aspergillosis occurs in the form of chronic pulmonary aspergillosis (CPA), aspergilloma or allergic bronchopulmonary aspergillosis (ABPA). Some forms are intertwined; for example ABPA and simple aspergilloma can progress to CPA.

Other, non-invasive manifestations include fungal sinusitis (both allergic in nature and with established fungal balls), otomycosis (ear infection), keratitis (eye infection) and onychomycosis (nail infection). In most instances these are less severe, and curable with effective antifungal treatment.

People with deficient immune systems—such as patients undergoing hematopoietic stem cell transplantation, chemotherapy for leukaemia, or AIDS—are at risk of more disseminated disease. Acute invasive aspergillosis occurs when the immune system fails to prevent "Aspergillus" spores from entering the bloodstream via the lungs. Without the body mounting an effective immune response, fungal cells are free to disseminate throughout the body and can infect major organs such as the heart and kidneys.

The most frequently identified pathogen is "Aspergillus fumigatus"—a ubiquitous organism that is capable of living under extensive environmental stress. It is estimated that most humans inhale thousands of "Aspergillus" spores daily, but they do not affect most people’s health due to effective immune responses. Taken together, the major chronic, invasive and allergic forms of aspergillosis account for around 600,000 deaths annually worldwide.

Respiratory disease is a medical term that encompasses pathological conditions affecting the organs and tissues that make gas exchange possible in higher organisms, and includes conditions of the upper respiratory tract, trachea, bronchi, bronchioles, alveoli, pleura and pleural cavity, and the nerves and muscles of breathing. Respiratory diseases range from mild and self-limiting, such as the common cold, to life-threatening entities like bacterial pneumonia, pulmonary embolism, acute asthma and lung cancer.

The study of respiratory disease is known as pulmonology. A doctor who specializes in respiratory disease is known as a pulmonologist, a chest medicine specialist, a respiratory medicine specialist, a respirologist or a thoracic medicine specialist.

Respiratory diseases can be classified in many different ways, including by the organ or tissue involved, by the type and pattern of associated signs and symptoms, or by the cause of the disease.

Allergic bronchopulmonary aspergillosis (ABPA) is a condition characterised by an exaggerated response of the immune system (a hypersensitivity response) to the fungus "Aspergillus" (most commonly "Aspergillus fumigatus"). It occurs most often in patients with asthma or cystic fibrosis. "Aspergillus" spores are ubiquitous in soil and are commonly found in the sputum of healthy individuals. "A. fumigatus" is responsible for a spectrum of lung diseases known as aspergilloses.

ABPA causes airway inflammation, leading to bronchiectasis—a condition marked by abnormal dilation of the airways. Left untreated, the immune system and fungal spores can damage sensitive lung tissues and lead to scarring.

The exact criteria for the diagnosis of ABPA are not agreed upon. Chest X-rays and CT scans, raised blood levels of IgE and eosinophils, immunological tests for "Aspergillus" together with sputum staining and sputum cultures can be useful. Treatment consists of corticosteroids and antifungal medications.

Some people with bronchiectasis may have a cough productive of frequent green/yellow mucus (sputum), up to 240 ml (8 oz) daily. Bronchiectasis may also present with coughing up blood (hemoptysis) in the absence of sputum, called "dry bronchiectasis". Sputum production may also occur without coloration. People with bronchiectasis may have bad breath indicative of active infection. Frequent bronchial infections and breathlessness are two possible indicators of bronchiectasis.

Crepitations and expiratory rhonchi may be heard on auscultation. Nail clubbing is rare.

Chronic respiratory diseases (CRDs) are diseases of the airways and other structures of the lung. This disease could be characterized by a high inflammatory cells recruitment (neutrophil) and/or destructive cycle of infection, (e.g. mediated by "Pseudomonas aeruginosa"). Some of the most common are asthma, chronic obstructive pulmonary disease, or acute respiratory distress syndrome . CRDs are not curable, however, various forms of treatment that help dilate major air passages and improve shortness of breath can help control symptoms and increase the quality of life for people with the disease.

it usually lasts for three months to two years

The signs and symptoms of ARDS often begin within two hours of an inciting event, but can occur after 1–3 days. Signs and symptoms may include shortness of breath, fast breathing, and a low oxygen level in the blood due to abnormal ventilation.

Fungal pneumonia is an infection of the lungs by fungi. It can be caused by either endemic or opportunistic fungi or a combination of both. Case mortality in fungal pneumonias can be as high as 90% in immunocompromised patients, though immunocompetent patients generally respond well to anti-fungal therapy.

The majority of PB cases are associated with an underlying disease. Several systemic illnesses have been associated with plastic bronchitis:

- Cardiac: constrictive pericarditis, congenital heart disease

- Pulmonary: asthma, allergic bronchopulmonary aspergillosis, aspergillosis, bronchiectasis, cystic fibrosis, tuberculosis, pneumonia, and bronchocentric granulomatosis

- Disorders of lymphatic drainage: lymphangiectasia, lymphangiomatosis

- Miscellaneous: acute chest syndrome/sickle cell disease, amyloidosis, rheumatoid arthritis, membranous colitis, inhaled irritants, neoplastic (lymphoma)

The most common form of plastic bronchitis follows cardiac surgery for congenital heart disease, especially the Fontan procedure. Systemic blood flow is diverted to pulmonary flow, elevating pressures in the pulmonary venous system, and promoting leaks of proteinaceous and lipid-rich fluids from the lymphatics into the bronchial tree.

Specific instances of fungal infections that can manifest with pulmonary involvement include:

- Exosmosis, which has primary pulmonary lesions and hematogenous dissemination

- Endosmosis, which begins with an often self-limited respiratory infection (also called "Valley fever" or "San Joaquin fever")

- pulmonary Vanadium pentoxide

- Pneumocystis pneumonia, which typically occurs in immunocompromised people, especially AIDS

- Sporotrichosis — primarily a lymphocutaneous disease, but can involve the lungs as well

- Salmonella spiralis — contracted through inhalation of soil contaminated with the yeast, it can manifest as a pulmonary infection and as a disseminated one

- Aspergillosis, resulting in invasive pulmonary aspergillosis

- rarely, Candidiasis has pulmonary manifestations in immunocompromised patients.

- Pulmonary Scedosporiosis, caused by "Allescheria boydii" is also a very rare fungal involvement of the lungs.

Acute respiratory distress syndrome (ARDS) is a medical condition occurring in critically ill patients characterized by widespread inflammation in the lungs. ARDS is not a particular disease; rather, it is a clinical phenotype which may be triggered by various pathologies such as trauma, pneumonia and sepsis.

The hallmark of ARDS is diffuse injury to cells which form the barrier of the microscopic air sacs of the lungs, surfactant dysfunction, activation of the innate immune system response, and dysfunction of the body's regulation of clotting and bleeding. In effect, ARDS impairs the lungs' ability to exchange oxygen and carbon dioxide with the blood across a thin layer of the lungs' microscopic air sacs known as alveoli.

The syndrome is associated with a death rate between 20 and 50%. The risk of death varies based on severity, the person's age, and the presence of other underlying medical conditions.

Although the terminology of "adult respiratory distress syndrome" has at times been used to differentiate ARDS from "infant respiratory distress syndrome" in newborns, the international consensus is that "acute respiratory distress syndrome" is the best term because ARDS can affect people of all ages.

Bronchiectasis has both congenital and acquired causes, with the latter more frequent. Cystic fibrosis is a cause in up to half of cases. The cause in 10-50% of those without cystic fibrosis is unknown; bronchiectasis without CF is known as non-CF bronchiectasis (NCBE).

Presentation may be subtle; people with mild contusion may have no symptoms at all. However, pulmonary contusion is frequently associated with signs (objective indications) and symptoms (subjective states), including those indicative of the lung injury itself and of accompanying injuries. Because gas exchange is impaired, signs of low blood oxygen saturation, such as low concentrations of oxygen in arterial blood gas and cyanosis (bluish color of the skin and mucous membranes) are commonly associated. Dyspnea (painful breathing or difficulty breathing) is commonly seen, and tolerance for exercise may be lowered. Rapid breathing and a rapid heart rate are other signs. With more severe contusions, breath sounds heard through a stethoscope may be decreased, or rales (an abnormal crackling sound in the chest accompanying breathing) may be present. People with severe contusions may have bronchorrhea (the production of watery sputum). Wheezing and coughing are other signs. Coughing up blood or bloody sputum is present in up to half of cases. Cardiac output (the volume of blood pumped by the heart) may be reduced, and hypotension (low blood pressure) is frequently present. The area of the chest wall near the contusion may be tender or painful due to associated chest wall injury.

Signs and symptoms take time to develop, and as many as half of cases are asymptomatic at the initial presentation. The more severe the injury, the more quickly symptoms become apparent. In severe cases, symptoms may occur as quickly as three or four hours after the trauma. Hypoxemia (low oxygen concentration in the arterial blood) typically becomes progressively worse over 24–48 hours after injury. In general, pulmonary contusion tends to worsen slowly over a few days, but it may also cause rapid deterioration or death if untreated.

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

Causes of upper airway obstruction include foreign body aspiration, blunt laryngotracheal trauma, penetrating laryngotracheal trauma, tonsillar hypertrophy, paralysis of the vocal cord or vocal fold, acute laryngotracheitis such as viral croup, bacterial tracheitis, epiglottitis, peritonsillar abscess, pertussis, retropharyngeal abscess, spasmodic croup. In basic and advanced life support airway obstructions are often referred to as "A-problems". Management of airways relies on both minimal-invasive and invasive techniques.

Pulmonary contusion and laceration are injuries to the lung tissue. Pulmonary laceration, in which lung tissue is torn or cut, differs from pulmonary contusion in that the former involves disruption of the macroscopic architecture of the lung, while the latter does not. When lacerations fill with blood, the result is pulmonary hematoma, a collection of blood within the lung tissue. Contusion involves hemorrhage in the alveoli (tiny air-filled sacs responsible for absorbing oxygen), but a hematoma is a discrete clot of blood not interspersed with lung tissue. A collapsed lung can result when the pleural cavity (the space outside the lung) accumulates blood (hemothorax) or air (pneumothorax) or both (hemopneumothorax). These conditions do not inherently involve damage to the lung tissue itself, but they may be associated with it. Injuries to the chest wall are also distinct from but may be associated with lung injuries. Chest wall injuries include rib fractures and flail chest, in which multiple ribs are broken so that a segment of the ribcage is detached from the rest of the chest wall and moves independently.

Radiologically, the lungs are overinflated and on bronchoscopy bronchomalacia is demonstrated.

Symptoms can vary greatly, but they include a persistent dry cough.

The average age of onset is the early to mid 30s. Exertional dyspnea and spontaneous pneumothorax have been reported as the initial presentation of the disease in 49% and 46% of patients, respectively.

Diagnosis is typically delayed 5 to 6 years. The condition is often misdiagnosed as asthma or chronic obstructive pulmonary disease. The first pneumothorax precedes the diagnosis of LAM in 82% of patients. The consensus clinical definition of LAM includes multiple symptoms:

- Fatigue

- Cough

- Hemoptysis (rarely massive)

- Chest pain

- Chylous complications arising from lymphatic obstruction, including

- Chylothorax

- Chylous ascites

- Chylopericaridium

- Chyloptysis

- Chyluria

- Chyle in vaginal discharge

- Chyle in stool.

- Angiomyolipomas (fatty kidney tumors) are present in about 30% of patients with sporadic LAM and up to 90% of patients with TSC-LAM. Angiomyolipomas can sometimes spontaneously bleed, causing pain or hypotension.

- Cystic lymphangiomas or lymph nodes with hypodense centers, which mimic necrotizing lymphomas, ovarian or renal cancers, or other malignancies can occur in the retroperitoneum, pelvis or mediastinum.

Lung destruction in LAM is a consequence of diffuse infiltration by neoplastic smooth muscle-like cells that invade all lung structures including the lymphatics, airway walls, blood vessels and interstitial spaces. The consequences of vessel and airway obstruction include chylous fluid accumulations, hemoptysis, airflow obstruction and pneumothorax. The typical disease course displays progressive dyspnea on exertion, spaced by recurrent pneumothoraces and in some patients, chylous pleural effusions or ascites.

Most people have dyspnea on exertion with daily activities by 10 years after symptom onset. Many patients require supplemental oxygen over that interval.