Blastomycosis symptoms can be present or absent, which can make it hard to diagnose.
Blastomycosis is a rare infection that develops when people breathe in a fungus found in wood and soil called blastomyces dermatitidis. Blastomycosis symptoms primarily affect the skin and lungs. According to the Centers for Disease Control and Prevention, 50 percent of people with blastomycosis report flu-like symptoms such as chills, fever, pleuritic chest pain and muscle aches; the other 50 percent are asymptomatic, meaning they do not show signs of the infection. Some patients with blastomycosis may also suffer from chronic pulmonary infection, while others may experience skin, bone and genitourinary tract infections. Another symptom of blastomycosis, while uncommon, affects the central nervous system and may result in meningitis. The time span between exposure and the development of symptoms can be as short as three weeks, but as long several months.
Individuals suffering from blastomycosis may experience mild respiratory symptoms that often start with a dry cough and fever. These early symptoms of blastomycosis may progress to include chest pain, weight loss and a persistent cough. Patients may experience several other symptoms in the early stages of blastomycosis such as shortness of breath, night sweats, coughing up blood and a feeling of tightness in the chest. Other common blastomycosis symptoms include fatigue, joint pain, rash, skin lesions and general discomfort.
Individuals with mild or moderately severe symptoms like those described above may be prescribed antifungal drugs such as intraconazole for treatment. Early treatment is often very effective. According to the University of Maryland Medical Center, patients with mild lung infections and minor lesions typically recover completely.
The more advanced symptoms of blastomycosis often spread beyond the lungs and can include infections of the skin, central nervous system and bones. Symptoms affecting the skin may cause enlarged lesions to develop on exposed parts of the body such as the ankles, feet, face, hands and wrists. These lesions affect up to 80 percent of patients with blastomycosis and may appear in one of the following forms:
Lesions can also look like warts and may range in color from violet to gray. Occasionally, pustule-lesions can become sensitive enough to bleed when rubbed or scratched. They may also appear in the mouth or nose. In some cases, these fungal lesions can travel through the blood and infect other organs like the bladder, kidneys, prostate and testes. If left untreated, these symptoms can result in further complications and possibly death.
Some individuals do not experience any of the symptoms most commonly associated with blastomycosis, which is one of the reasons the infection can be so difficult to diagnose. In these cases, doctors usually find evidence of a blastomycosis infection in their patient's blood tests and chest X-rays. In addition, blastomycosis symptoms may spontaneously improve or disappear entirely without medical treatment. According to the Marshall Clinic, some individuals infected with blastomycosis may become ill immediately, while others may go weeks without knowing they're sick. While there is no vaccine that can prevent blastomycosis, there are several antifungal medicines that can be used to treat symptoms associated with the disease.
In addition to affecting humans, blastomycosis also affects dogs and occasionally cats. Dogs may develop blastomycosis by inhaling spores after churning up infected soil. According to the Minnesota Board of Animal Health, canine blastomycosis is a common disease for dogs and occurs more often in canines than in humans. Also, if left untreated, it can lead to death. The College of Medicine at the University of Minnesota reports that dogs infected with blastomycosis may experience a wide range of symptoms including loss of appetite, weight loss, shortness of breath, cough, skin lesions and eye disease. Other uncommon symptoms experienced by dogs include fever, lack of energy, raspy bark and brain, kidney and bone infections. Symptoms will typically develop within two to three weeks after a dog is exposed to the fungus. Fortunately, blastomycosis cannot be transmitted from animals to people or vice versa. However, individuals can possibly develop the disease by coming in contact with a common environmental source shared with an infected pet, such a patch of infected soil or stagnant air filled with fungal spores.