Aspergillosis: causes, symptoms and treatment
Fungi do not always behave as pathogens. What’s more, of the 600,000 potential species of fungi in the world, most are completely harmless, and some are even beneficial. to us, like edible mushrooms or microscopic fungi used in the food industry to make beer or cheese.
But it is true that although viruses, bacteria, and parasites are the most well-known pathogens due to their clinical relevance, fungi can also be infectious agents. Most of these pathogenic fungi infect external tissues and organs, the skin being the most susceptible, when they develop disorders known as athlete’s foot, dermatophytosis, or onychomycosis, which are not dangerous diseases beyond discomfort.
However, especially in people with weakened immune systems and/or pre-existing pathologies, fungi can infect internal tissues and organs, leading to fungal diseases, although these are rarely life-threatening and require an immediate clinical approach.
And one of these fungal pathologies is aspergillosis, an infection in the lungs caused by Aspergillus fumigatus that colonizes these respiratory organs and causes pneumonia that can be fatal without treatment. Let’s see its causes, symptoms, complications, and treatment.
What is aspergillosis?
Aspergillosis is a rare fungal disease that affects immunocompromised people and/or those with previous respiratory pathologies that involve the fungus Aspergillus fumigatus. The fungus takes advantage of this weakening of the immune system to, after entering the lungs by inhaling spores, colonize and grow in these respiratory organs, resulting in life-threatening pneumonia without immediate treatment.
Infection with this fungal pathogen causes the characteristic symptoms of pneumonia: shortness of breath, bloody sputum (due to all the physical injuries the fungus causes as it grows), weight loss, high fever, cough, and difficulty breathing. breathe. If not under powerful antifungal drug therapy, it can lead to the death of the patient.
However, it should be noted that it is a very rare disease in the general, healthy population. As previously stated, Aspergillus fumigatus lung infection occurs only in people with compromised immune systems and/or a history of respiratory disease.In fact, it is a fungus that occurs naturally in the environment (even inside homes) and with which we often come into contact with spores, but a healthy immune system prevents them from colonizing.
Therefore, it is an invasive mycosis, and although it is rare, its frequency is increasing worldwide. In the 1990s, an epidemiological study increased the incidence of aspergillosis by 1 case per 100,000 inhabitants, although this figure is believed to increase by 3% each year. The reasons for this are not very clear, but it is clear that, depending on the country and the hospital resources that can be offered, its mortality is between 30% and 95%.
reasons
The cause of the development of aspergillosis is a combination of two factors: the inhalation of Aspergillus fumigatus spores and previous immunodeficiency and/or respiratory disease such as cystic fibrosis or asthma. and this is very important. Because even if we are exposed to the fungus, if our immune system is fine, there will be no problem.
Aspergillus is a genus of filamentous fungi (composed of cell chains called hyphae) that, according to the latest calculations, includes 339 different species of molds. One of them, of course, is Aspergillus fumigatus, a fungus that is non-pathogenic despite its appearance. at least not at first.
Aspergillus fumigatus, like the rest of the species in its genus, is a saprophytic fungus, which means that it grows on the decomposition of organic matter and is found in soils where it eats on bodies, dead leaves, or excretions, doing extracellular digestion.
This is done by Aspergillus fumigatus, a fungus with a wide and homogeneous distribution of great importance in the nitrogen and carbon cycles. With a size between 2 and 3 microns, it is found naturally in many environments, including indoors.
And, like a fungus, it reproduces by releasing spores into the air. And here, what can happen? Single. We inhale them, and through the respiratory system, they reach the lungs. Unless we have a previous respiratory disease such as asthma or cystic fibrosis and a weakened immune system, nothing will happen. Immune cells neutralize the spores before developing a lung infection.
Also, most varieties are not capable of developing an infectious process. However, if the conditions of inhalation of pathogenic spores are aggravated and the person suffers from previous immunodeficiency and/or respiratory pathology, there is a risk of developing said aspergillosis.
Therefore, the most important risk factors are a weakened immune system (due to disease or from taking immunosuppressive drugs after transplant), air spaces (pulmonary cavities) in the lungs, having asthma or cystic fibrosis, and long-term suffering. treatment with corticosteroids, low levels of white blood cells, suffering from chronic granulomatous disease, receiving aggressive hospital treatments (such as chemotherapy), and, in general, being at risk of opportunistic infections.
Remind us, yes, that it is a rare disease; although it is difficult to assess all cases, there could be an occurrence of 1 case per 100,000 people. It is estimated that each year, between 1 and 4 million cases occur worldwide.
signs
The clinical signs depend on many factors, since, as we have seen, the person’s state of health is undoubtedly the most relevant in the development of this opportunistic pulmonary infection. In fact, we can divide aspergillosis into three versions according to its characteristics:
It is the most serious form (and also the least frequent), and, as seen in cases of high immunity as a consequence of chemotherapy, immunological diseases, or bone marrow transplantation, it is the one with the highest mortality rate.
Coughing, shortness of breath, fatigue, weight loss, wheezing, and passing bloody sputum are just the first respiratory symptoms to come to light when Aspergillus fumigatus is growing in the lungs.
The problem is that it can be transferred to other regions of the body. spread a fungal infection to the skin, kidneys, heart, and even the brainpread a fungal infection to the skin, kidneys, heart, and even the brain. At that time, headaches, eye symptoms, severe shortness of breath, joint pain, a very high fever, chills, a runny nose, etc. begin.
Technically known as allergic bronchopulmonary aspergillosis, it is a type of aspergillosis whose symptoms are not visible due to colonization and lung damage. aspergillus fumigatus, but due to an allergic reaction to its presencetype of aspergillosis whose symptoms are not visible due to colonization and lung damage. aspergillus fumigatus, but due to an allergic reaction to its presence. It does not require an immune state, so it is usually milder.
In general, people with asthma (2.5% allergic aspergillosis) or cystic fibrosis (1–15%)) are more likely to have allergic reactions to the presence of the fungus. Fever, cough with blood, mucus plugs, and worsening asthma are some of the symptoms.
It is a variant of aspergillosis. aspergillosis that affects people with chronic lung diseases (tuberculosis, sarcoidosis, or emphysema) by forming a cavity or air spaces in the lungs. Aspergillus fumigatus can take advantage of this and form fungal growths (masses of entangled hyphae within these lung cavities), also known as aspergillomas.
What this aspergilloma does is make the chronic respiratory disease worse, so while symptoms may be mild at first, over time (if untreated), they may include shortness of breath, fatigue, coughing up blood, wheezing, and a leaden breath. unintentional weight loss.