Aspergillus niger - what is it? Morphology, treatment

Aspergillus niger is the most common pathogenic fungus, familiar to us by the frightening name "black mold". You can find whole colonies of this amazing adaptive organism right at home - in the basement, in a dark damp corner, in an old book.

Morphology and physiology of Aspergillus niger

What kind of mushrooms are Aspergillus niger? They are able to settle down and grow into a colony even at temperatures above ⁺ 40 ⁰ С. The maturation rate of mushrooms during capture of significant areas is simply unique - within three days. Darken, acquiring a characteristic dark gray or black color, fungi as the conidia ripen - microscopic formations on the apex of the thickened conidial head of the parasitic organism.

The morphology of Aspergillus niger implies several strains of black mold, which selects the place of its habitat for rooms, foodstuffs or even the human body.

A favorable environment for black mold

Mold spores are present everywhere, they are not present only in conditions of complete sterility or vacuum. Particles that have separated from the mycelium, are floating in the air and begin to multiply actively wherever the dispute can catch on and go unnoticed.

The mold itself is formed from two filamentary bodies, one of which creates a vegetative formation, while the other stretches upward and matures, giving life to new disputes.

Favorable factors contributing to good survival of Aspergillus niger:

• Absence of inflow and outflow of fresh air; This creates a stuffy, saturated with evaporation atmosphere, which is ideal for the emergence of multiple mold colonies;
• Humidity, close to 100%, is one of the most common conditions in which it is possible to detect Aspergillus niger;
• Sharp temperature jumps, which tend to form steam and condensate;

In addition, one of the factors is the insufficient tightness of packages with products.

Strains of Aspergillus niger

No type of mold is similar to the other, if we consider the structure of the fungi under a microscope. The expressive and frightening appearance of black mold markedly distinguishes it from the light fluffy Aspergillus pellets of another species that seem less dangerous, but this is misleading. Black can be a mycelium of several strains at once, depending on the periods of ripening of the fungus, the type of the enclosed surface and the speed of distribution of the colony.

There are such strains of Aspergillus niger:

• The color of the mycelium is light, only the ripening spores are black. Such a fungus lives in the dark damp corners of residential and non-residential premises and is the cause of aspergillosis disease.
• Phoma - refers to the 4th group of pathogenicity. They, on the contrary, have a vegetative body as a black blot with a white edge of ripening spores.
• The next kind always has a deep dark color. Separated spores readily settle in the human digestive tract and cause intoxication and a marked allergic reaction.
• There is a kind of awesome dark color and with rare vitality, but at the same time almost not dangerous for human health.
• Among the varieties of black mold - and penicillin-type fungi, often grown in complex adaptive conditions to obtain a valuable substance on the basis of which antibiotics are made.
• The mycelium of the following species resembles spots of a slimy plaque, arising on long-lying vegetables, fruits, nuts.

So Aspergillus nigeria is not only a substance of deep mourning color familiar to us. Hiding an ominous fungus can also be quite harmless white fluff.

Infection with Aspergillus niger fungi

Aspergillosis is a consequence of inhalation by a person of a freely dispersed spore of black mold. Most often, fungus attacks are exposed to people whose professional activities are related to conditions in which mold feels most comfortable. These are grain processing, bakery production, shops for aging ready-made cheeses, weaving and spinning mills.

A healthy person can breathe spared air without danger to himself, but weakened immune defense, transferred or actual diseases of the bronchi, lungs, and nasopharyngeal sinuses make the body vulnerable. Based on the initial strain of the fungus, which has settled in the humid environment of the body, a specific type of aspergillosis develops.

Infection with Aspergillus niger fungus can occur in other ways:

• Through food;
• Through wounds, microcracks on the epidermis or mucous membranes.

Sometimes successful penetration of the fungus into the human body is facilitated by the transferred radiation therapy and prolonged therapy with antibiotics.

Symptoms

Despite the fact that the fungus spores are able to gain a foothold on any organ, the most frequent zone of their lesions is oxygenated lung tissue. An infected person experiences all the symptoms of acute bronchitis:

• A strong cough with spitting expectoration of dirty white, sometimes - with the presence of bloody clots;
• Constant fatigue, weakness, a general decrease in activity;
• Loss of body weight.

Treatment, which does not correspond to the elimination of the cause of the disease, leads to the development of pulmonary mycosis. This stage of lung damage is characterized by worsening of the patient's condition. Appear:

• A severe wet cough with a stable mucous compartment;
• chills;
• chest pain;
• dyspnea;

If the biological material (sputum) is examined at this stage of the disease, Aspergillus spores are found in the secretions.

Aspergillosis of the hearing and nasopharyngeal organs, can resemble rhinitis, sinusitis, otitis, pharyngitis, tonsillitis according to the flow algorithm. Distinctive features of the defeat of the fungus ENT organs are:

• Peeling of the external auditory canal and itching in this area;
• Hearing impairment;
• hyperemia.

With the progression of the disease, the auditory passage is indicated by the presence of a gray friable substance. The study of the sample will give a positive result for the presence of a parasitic mycelium.

Infection with aspergillosis of the eye is masked under:

• Blepharitis;
• Dacryocystitis;
• conjunctivitis.

The lack of proper treatment leads to complications in the form of partial or complete loss of vision.

So, it is already approximately understandable that for the fungi Aspergillus niger. On their hands (which is manifested primarily by the defeat of the nail plate), they too can settle. The signs of this infection are difficult to confuse with other types of disorders in the body. They are as follows:

• The appearance of dark scales;
• Itching around the nail;
• infiltration;
• A heavy smell coming from the nail.

Over time, if you do not use complex therapy, the nail color changes to yellow-brown or green-brown, the plate thickens and acquires a porous structure.

Diagnostics

Biological materials for research with suspicion of Aspergillus are samples taken from the suspected lesion zone. In skin lesions, these are scrapings from the epithelium or nail, with lung damage - sputum discharge. To determine the fungus, a clinical analysis of blood and urine may also be required.

Sometimes culture can be isolated only through serological tests and culture. It is possible that with severe lesions of the epidermis the doctor insists on carrying out skin-allergic tests.

Only after confirming aspergillosis and establishing its form, the patient is sent to a narrow-profile specialist for treatment.

Traditional treatment of aspergillosis

Local treatment of Aspergillus niger occurs in combination with preparations of antifungal direction: amphotericin B, voriconazole, flucytosine, itraconazole. The method of using drugs - by inhalation, intravenously or orally, is discussed with the doctor based on the nature and extent of damage to the body.

Means for topical application are antiseptics and antifungal agents. Treatment of cutaneous aspergillosis is most favorable, according to forecasts, but only on condition that the patient will undergo a full therapeutic course lasting from a month to three.

Aspergillosis of the lungs in advanced or complex form gives a high percentage of mortality - up to 50%. Factor aggravating the patient's condition and worsening the prognosis is weakened immunity.

A life threatening form of the disease may require the patient to stay in the hospital, but, as a rule, the therapy is carried out at home with periodic delivery of control tests. Treatment of Aspergillus nigeria with folk remedies is unacceptable!

Aspergillosis in children

As in adults, Aspergillus niger in children develops in several forms:

• Allergic bronchopulmonary aspergillosis;
• Aspergillus bronchitis;
• Aspergillosis pneumonia.

The common symptoms with which aspirigellosis is masked for bronchial and acute respiratory diseases are shortness of breath, coughing with sputum, and chest pain. Sometimes symptomatology is accompanied by an increase in temperature.

Recognized Aspergillus by the nature of sputum, which is putrefactive or dirty-gray color, in the advanced stage - with a bloody admixture.

From the bouquet of signs addressed to the doctor as a complaint of health, the pediatrician should make a general picture of the doctor and prescribe a diagnosis, which includes laboratory tests of blood and sputum, as well as skin tests. After confirming the presence of aspergillas in biological material, it may be necessary to make more precise examinations or samples that are designed to determine the degree of damage to the body:

• CT scan;
• Spirometry;
• Bronchoscopy;
• biopsy.

Surveys are conducted quickly to prevent the main complication - sepsis, in which fungi spread to healthy organs.

Treatment of aspergillosis in children

Hospitalize the child immediately after diagnosis. From the first day in the body of the patient antifungal drugs are being introduced, which suppress the spread of aspergillus. Reception of immunomodulators is an important point in the treatment of Aspergillus nigeria in children, since it is the weakening in the protective reaction of the body that led to aspergillosis.

In rare cases, resort to surgical treatment - when the affected area of the lung can not be saved and a decision is made to remove it. Indication for such a cardinal action is the bleeding from the tumor that appeared when the aspergilloma was formed, a particularly complex form of aspergillosis.

Prevention

Black mold is most often found by residents of old houses or corner apartments in high-rise buildings, so in this type of premises, the walls should be inspected as closely as possible. Aspergillus likes to hide behind straggler wallpaper, tile, in hammered ventilation. At least once every three months, it is necessary to perform a general cleaning of the sanitary unit using antibacterial agents and grouts.

Do not allow dampness in the basement of the house, the appearance of deposits of decaying vegetables. Wooden shelves, floors in damp premises are not allowed. If the house has a section of the wall regularly covered with mold, despite all measures, it is necessary to pay attention to the integrity of the wall in this place.