Fusariosis is an infectious disease caused by an opportunistic fungus, Fusarium spp., Which can be found in the environment, mainly in plantations. Fusarium spp. it is more frequent in people who have an impaired immune system, either due to hematological diseases or due to bone marrow transplantation, for example, being more common in these cases the occurrence of disseminated fusariosis, in which the fungus can reach two or more organs, worsening the person's clinical condition.
The main species of Fusarium capable of causing disease in people are Fusarium solani , Fusarium oxysporum , Fusarium verticillioides and Fusarium proliferatum , which can be identified through laboratory tests.
Symptoms of Fusarium spp.
Symptoms of Fusarium spp. they are not very specific, since they are similar to the symptoms of other diseases caused by fungi, it depends on the person's immune system, as it is an opportunistic fungus, and can vary according to the location of the fungus in the body. The main signs and symptoms of fusariosis are:
- Fever; Muscle pain; Skin lesions, which are painful and can develop into ulcers and are most often seen on the trunk and extremities; Decreased levels of consciousness; Corneal inflammation; Alteration of color, thickness and shape of the nail, in addition the presence of pus can be verified in some cases; respiratory, cardiac, hepatic, renal or neurological problems, depending on the location of the fungus.
Fusarium spp. it is more common to happen in people with hematological diseases, neutropenia, who have undergone bone marrow transplantation or chemotherapy, who have used prophylactic antifungals in order to prevent infection by Candida sp., for example, and have a disease that compromises the immune system.
How is contagion
Fusarium spp. it happens mainly through the inhalation of spores present in the environment, since this fungus is found mainly in plants and in the soil. However, the infection can also happen through direct inoculation of the fungus, most of the time as a consequence of a cut caused by a branch, for example, resulting in fungal keratitis.
Fungal keratitis is one of the clinical manifestations of infection by Fusarium spp. and corresponds to inflammation of the cornea that can result in blindness, and it is important that it is identified and treated through corneal transplantation as soon as possible to prevent the spread of the fungus. In addition, Fusarium keratitis can happen due to the use of contact lenses contaminated by this fungus. Learn more about keratitis.
How the diagnosis is made
The diagnosis of fusariosis is made by an infectious disease physician or general practitioner through the evaluation of the signs and symptoms presented, in addition to the results of laboratory tests. The test that confirms the infection with Fusarium spp. it is the isolation of the fungus in the infected places, which can be skin, lung or blood according to the patient.
After isolation and culture, microscopic observation is performed to check the fungus responsible for the infection. Although this is the diagnostic method that confirms fusariosis, these techniques take time, as it takes time for the fungus to grow sufficiently so that it can be observed under the microscope. In addition, isolation and observation do not allow the identification of the species responsible for the infection, requiring the use of molecular techniques to make the identification, which also requires time.
Immunological techniques can also be used to identify Fusarium spp., And aim to identify components of the fungal cell wall, however these techniques are not specific for the identification of Fusarium spp, as the component sought is also part of other fungi, such as Aspergillus sp., for example, which can confuse the diagnosis.
Despite the isolation and identification of the fungus requires more time, tests are still indicated to confirm the infection. In addition, histological examination can be performed, in which tissue biopsy is performed and, if the presence of fungus is identified, prophylactic treatment can be started while waiting for the culture result.
Fusariosis Treatment
Fusariosis is treated with antifungals that should be used according to the doctor's recommendation, with Amphotericin B and Voriconazole being the most indicated. Amphotericin B is the main antifungal indicated in disseminated fusariosis, however this drug is associated with high levels of toxicity and some patients do not respond to treatment, and the use of Voriconazole is recommended.
Fusarium spp. it has intrinsic resistance to Fluconazole and antifungals belonging to the echinocandin class, such as Micafungin and Caspofungin, which makes treatment difficult and may be associated with high rates of morbidity and mortality.
