Systemic Fungal Infection, Systemic Mycosis (Fungal Infection that Affects Various Organs Such as Skin, Nose, Brain, Lungs) in cats
- Occurrence: common
- Location of illness: General/Whole body, Skin/Fur
Systemic fungal infections, also known as systemic mycoses, are infections that can affect various organs and tissues in cats, including the skin, nose, brain, and lungs. These infections are caused by pathogenic fungi that enter and spread throughout the body.
The most important facts at a glance
Systemic fungal infections in cats, also known as systemic mycoses, are caused by fungi that can affect various organs such as the skin, nose, brain, and lungs. These infections are often caused by dimorphic fungi that occur as mold in the environment and change to the yeast form in the cat’s body. The most common pathogens include Cryptococcus neoformans, Histoplasma capsulatum, Coccidioides immitis, and Blastomyces dermatitidis. Susceptibility to infections can be increased by genetic factors or a weakened immune system, such as from diseases like FIV or FeLV. Symptoms include Skin lesions, Fever, weakness, and Respiratory distress. Diagnosis requires a thorough examination by a veterinarian, supplemented by blood tests, imaging procedures, and possibly biopsies. Treatment is usually with antifungals, which must be administered over a long period of time. In severe cases, surgical intervention may be necessary. The prognosis depends on various factors, including the speed of diagnosis and the response to treatment. For prevention, the cat’s environment should be kept clean and dry, and a balanced diet and regular veterinary check-ups are important. Stress should be avoided to strengthen the cat’s immune system.
Causes
Fungi are a diverse group of microorganisms that are widespread in the environment. They consist of cell walls containing chitin and other polysaccharides, which distinguishes them from bacteria and plants. Fungi can occur either as yeast (unicellular form) or as mold (multicellular form), and some species are dimorphic, meaning they can switch between these two forms depending on environmental conditions.
Systemic fungal infections in cats are often caused by dimorphic fungi that grow as mold in the environment and transition to a yeast form when they enter the cat’s body. This can happen when fungal spores are inhaled or have entered the skin through Wounds.
The most common fungi that cause systemic infections in cats are Cryptococcus neoformans, Histoplasma capsulatum, Coccidioides immitis, and Blastomyces dermatitidis. These fungi are more common in certain geographic areas, meaning that the likelihood of infection depends on the environment in which a cat lives or travels.
The causes for the occurrence of systemic fungal infections are diverse. Some cats may be more susceptible to infections due to genetic factors or a weakened immune system, such as from diseases like FIV (Feline Immunodeficiency Virus) or FeLV (Feline Leukemia Virus). Stress and poor nutritional conditions can also weaken the immune system and increase the risk of infection.
Symptoms
The symptoms of a systemic fungal infection in cats can vary depending on the organ affected. Because these infections can affect multiple organs and tissues, the clinical signs are often non-specific and can mimic other diseases.
Cats with a systemic fungal infection of the lungs may show symptoms such as Cough, shortness of breath, or an increased respiratory rate. Nasal infections can lead to nasal discharge, Sneezing, or a stuffy nose. Skin infections can cause Skin lesions, nodules, or ulcers.
If the central nervous system is affected, which can occur with some fungal species such as Cryptococcus neoformans, neurological symptoms may occur. These include Behavioral changes, Convulsions, ataxia (Coordination disorders), and Head shaking.
General symptoms that may indicate a systemic infection include Fever, Weight loss, loss of appetite, lethargy, and lymphadenopathy (swollen lymph nodes). Because these symptoms can have many causes, an accurate diagnosis is essential.
Diagnosis
Diagnosing a systemic fungal infection requires a thorough history and a comprehensive clinical examination by a veterinarian. Due to the non-specific symptoms, additional diagnostic tests are necessary to make an accurate diagnosis.
Blood tests can provide evidence of an infection by showing inflammatory markers and signs of a systemic reaction. Serological tests can detect specific antibodies against certain fungi, which can be helpful in identifying the pathogen.
Imaging techniques such as X-rays or ultrasound examinations can visualize changes in the affected organs, e.g. lung changes in a pulmonary infection. Computed tomography (CT) or magnetic resonance imaging (MRI) may be necessary to assess the extent of an infection in the brain or other deep structures.
A definitive diagnosis often requires the detection of fungi in affected tissues. This can be done through biopsies or fine needle aspirations, in which a tissue sample is taken and examined microscopically. In some cases, cultivation of the fungus from body fluids or tissue samples may also be necessary.
Therapy
Treatment of systemic fungal infections in cats typically involves administering antifungals, which can be given orally or, in severe cases, intravenously. Commonly used antifungals include itraconazole, fluconazole, and amphotericin B, with the choice of medication depending on the type of fungus and the organ affected.
Treatment can take several months, as fungal infections are often persistent and require long treatment times to ensure complete killing of the fungi. It is important that treatment is not stopped prematurely, even if symptoms have disappeared, as this can lead to a relapse.
In some cases, supportive treatment may be necessary to relieve symptoms and promote the cat’s recovery. This may include administering anti-inflammatory drugs, pain relievers, or other supportive therapies, depending on the individual needs of the cat.
In severe infections, surgical intervention may be required to remove infected tissue or drain Abscesses. However, this is usually only necessary if other treatment methods are insufficient.
Prognosis and follow-up care
The prognosis for cats with systemic fungal infections varies greatly and depends on several factors, including the type of fungus, the organ affected, the extent of the infection, and the cat’s general health.
Early diagnosis and treatment are crucial for a better prognosis. Cats that respond quickly to treatment and have not suffered severe organ damage usually have a good to satisfactory prognosis.
In severe cases, or if the infection affects the central nervous system or other vital organs, the prognosis may be unfavorable. Some cats require long-term therapy, and in rare cases, the infection can be fatal.
Continuous monitoring and follow-up by the veterinarian are important to assess treatment progress and detect possible relapses early.
Prevention
To prevent systemic fungal infections in cats, it is important to control the environmental conditions in which the cat lives. Keep the environment clean and dry, as moist conditions can promote the growth of fungi. Regular cleaning of cat beds, toys, and feeding areas can significantly reduce the risk of infection.
A balanced diet strengthens your cat’s immune system, making it better equipped to fight off infections. Make sure your cat has access to high-quality food and drinks enough water. Regular veterinary check-ups are also important to detect and treat health problems early.
Avoid letting your cat roam freely in areas known for fungal infections, such as damp forests or areas with lots of foliage and rotting wood. If your cat is an outdoor cat, you should regularly check it for signs of infection and seek veterinary attention immediately if you suspect anything.
Finally, it is important to minimize stress in your cat, as stress can weaken the immune system. Provide a calm and safe environment where your cat feels comfortable to promote its overall well-being.