VERIFIED CONTENTAuthor: lek. Katarzyna Banaszczyk

Mucormycosis belongs to fungal diseases. Although mycoses of most of us seem to be a minor disease, in people with reduced immunity they can even lead to death. How is mucormycosis manifested and what forms of this disease are there? What is the prognosis and treatments for mucormycosis?

Mukormycosis , also known aszygomycosis , is an invasive fungal disease. The fungi responsible for the development of mucormycosis (i.e. mainly the fungi of the genus Mucorales, most often Rhizopus spp., Lichtheimia spp., Mucor spp.) Are mainly found in soil and decaying organic matter. The first described case of this disease concerned a patient with uncontrolled diabetes and dates back to 1885.

Dear infection

Infection can occur through inhalation of fungal spores (this predisposes to the development of the pulmonary form and the sino-cerebral form), but also through ingestion (then the gastrointestinal tract is infected) and transdermally (through injuries and cuts, then it develops the skin form of this disease).

Hospital infection is also possible - typically through medical equipment contaminated with fungal spores. The possibility of spreading infection between people has not been described so far.

Mukormycosis - risk factors

There are certain factors that predispose to the development of mucormycosis. The first group of these factors is associated with conditions that lower the body's immunity. We can include here:

  • improperly treated, decompensated diabetes,
  • presence of neoplastic diseases,
  • hematopoietic cell transplant,
  • neutropenia - a reduced number of neutrocytes belonging to white blood cells, which play a very important role in the proper course of immune processes,
  • monocytopenia - a decrease in the number of monocytes, which also belong to white blood cells,
  • immunosuppressive treatment - i.e. inhibiting the activity of the immune system - immunosuppressive drugs include, among others, steroids, cyclosporine, methotrexate, or some biological drugs,
  • coexistence of opportunistic infections- i.e. those that are typically found in immunocompromised people - for example, HIV patients,
  • cachexia, element and vitamin deficiencies,
  • having COVID-19 disease.

Other risk factors for developing mucormycosis are:

  • taking drugs, injuries, burns - which predisposes to skin mucormycosis,
  • treatment with deferoxamine - a drug typically used in the case of excess iron in the body,
  • eating fermented porridge that contains fungus spores,
  • drinking alcoholic beverages made from corn,
  • use of plants, herbs contaminated with spores,
  • using spore-contaminated tools for examining the oral cavity (infections possible, e.g. in dentistry).

Symptoms of mucormycosis

The symptoms that accompany this fungal disease depend primarily on the form of the disease. It is worth mentioning here that we distinguish mucormycosis:

  • sino-cerebral,
  • pulmonary,
  • skin,
  • digestive tract,
  • spread.

Sino-cerebral mucormycosis

Inhaling the spores, which then enter the paranasal sinuses, lead to the development of this form of the disease. The mycelium formed in the sinuses grows and destroys not only the tissue of the sinuses but also adjacent areas, including the eye socket. The central nervous system (brain) is also involved.

The first symptoms may resemble sinusitis, as there is pain in the sinus projection, fever, and an already disturbing swelling of the orbit. Symptoms that indicate an involvement of the nervous system are:

  • palsy of cranial nerves,
  • drooping eyelid,
  • eyes bulging,
  • disorders of the mobility of the eyeball,
  • blindness.

Pulmonary Mucormycosis

The symptoms that accompany lung involvement by mucormycosis are not very specific and are not very helpful in making a diagnosis. The most common symptoms of this condition are:

  • fever,
  • cough, rather dry,
  • sometimes shortness of breath, hemoptysis,
  • chest pain.

Patients with such symptoms are often treated for aspergillosis, but it does not bring the expected improvement. It is worth mentioning that the bronchi and trachea may also be involved, and the development of atelectasis, i.e. a state of reduced aeration of the lungs, may occur.

The mycelium can grow in a continuous pathway and occupy the chest vessels, the chest walls, the mediastinum, and even the pericardium.

Gastrointestinal mucormycosis

Very often fatal.The mycelium infiltrates, inter alia, the gastrointestinal wall and destroys it, leading to perforation. What's more, blood vessels are also involved and destroyed, leading to intra-abdominal hemorrhages.

In addition, the mycelium can occupy the pancreas, liver and spleen.

Mucormycosis results in peritonitis, sepsis and a sharp abdomen, which is a very serious clinical condition.

Mucormycosis of the skin

The cutaneous form of mucormycosis is manifested primarily by the presence of hardened necrosis with a crust surrounded by erythema. Not only the skin may be involved, but also the subcutaneous tissue.

Infection can spread to tendons, muscles, and bones and lead to the development of disseminated disease.

Disseminated Mucormycosis

The disseminated form of this fungal infection is associated with the spread of mycelium through the blood vessels to many organs of the body. Unfortunately, this form of mucormycosis is associated with 100% mortality.

It is worth noting that the clinical picture of this disease resembles another invasive fungal infection - called aspergillosis.

Diagnostics of mucormycosis

With regard to blood tests - peripheral blood counts show leukocytosis, i.e. an increase in the number of white blood cells, but it is not a specific symptom, as it typically accompanies infectious diseases.

If sino-cerebral mucormycosis is suspected, imaging tests such as computed tomography with contrast or magnetic resonance imaging (MRI) are performed. These studies allow to assess the advancement of destructive processes in tissues. Monitoring the effectiveness of the treatment applied is also possible thanks to imaging tests.

With regard to pulmonary mucormycosis, imaging tests can reveal changes such as:

  • infiltration, thickening,
  • nodules, presence of cavities, atelectasis,
  • pleural effusion,
  • enlargement of the lymph nodes,
  • thickening of the tracheal wall.

In some situations, however, the X-ray image of the lungs is normal, which does not exclude mucormycosis.

In order to confirm the disease, it is necessary to take material for histological examination (under a microscope). This test looks for the presence of a thick fungus hypha, characterized by the fact that its branches extend at right angles. The material for the study is usually collected by biopsy.

Treatment of mucormycosis

If this condition is suspected and confirmed, it is important to start treatment as soon as possible. Typically used:

  • amphotericin B - intravenously, use the full dose of the drug immediately (5-10mg / kg / day). This substance has an antifungal effect, it works by changing the permeability of the fungal cell membrane, which causes the outflow of the cell contents and its subsequent death,
  • posaconazole, isavuconazole - these are substances used as alternative drugs when amphotericin B cannot be used,
  • isavuconazole - this antifungal substance is used when the disease progresses.

Mucormycosis causes tissue necrosis, which is why in many cases surgical treatment and excision of necrotic fragments are necessary. Treatment of this fungal disease is certainly not easy, it requires time and a lot of medical experience.

Initially, it takes place in a hospital setting. The duration of treatment is individual, depending on the state of the patient's immune system, and in some situations the therapy may last even several years.

It should be emphasized that it is also extremely important to treat the underlying disease (diabetes, cancer, immunodeficiency), as this condition predisposed to the development of mucormycosis.

It is worth mentioning that some immunocompromised patients (e.g. neutropenic patients) are given prophylactic drugs (e.g. posaconazole) to prevent the development of mucormycosis. Unfortunately, there is no immunization that would protect against the disease and the effects of mucormycosis.

Mukormycosis - year-round

Unfortunately, this disease is characterized by a rapid course and quite high mortality. As already mentioned, in the disseminated form it is 100% of the cases. In turn, the sino-cerebral form has a mortality rate of 50-70%, the pulmonary form about 75%, and the cutaneous - 15%.

The course of the disease depends primarily on the functioning of the immune system of the patient and the accompanying comorbidities.

To sum up, this disease is rare, but people with decreased immunity, after transplantation or during oncological treatment are exposed to it. Mucormycosis is a disease of which infectious diseases physicians and oncologists who treat patients in a state of immunosuppression (with reduced immunity) know the most.

If people with risk factors for the development of this mycosis want to prevent the disease, they should first of all avoid contact with decomposing biological matter (plant and animal matter), because it is a typical place of living for fungi that cause mucormycosis. It should be emphasized that the prompt initiation of appropriate treatment increases the chances of survival from about 40% to 80%.

Category:

Infectious diseases