Blastomycosis – causes, symptoms, diagnosis, treatment

Last Updated on March 14, 2023 by Dr. Saqib Mueed

An infection which is caused by a Blastomyces fungus is known as blastomycosis. It is a fungal disease and also a fatal disease which mostly occurs in animals like dogs (which mostly live in the United States, Canada, Africa), humans, and cats. These all animals are caused by the organism Blastomyces dermatitidis.

This disease was firstly studied by a scientist T.C Gilchrist. So, the reason is that this disease we also called Gilchrist disease. We thirdly called this disease Histoplasmosis. Histoplasmosis is harmful for the lungs, so this disease also causes serious infection in lungs. Bird feces which are full of soil contaminated inhaling spore of a fungus lives in the soil near the riverbeds such as Ohio River valley.

It is a spinal disease in young and old aged people. This disease also affects their hosts and has a broad range in phylum mammals. This pulmonary disease is mainly caused by fungus. Blastomycosis results in a blood disease like pneumonia and other many skins, bones, CNS (Brain and spinal cord), joint diseases.

The fungal disease blastomycosis mainly causes disease in dogs and other people. Blastomycosis fungus are present in the environment specially in moist areas or moist soil and wood, leaves which are decomposing matter. People can get this disease after inhaling microscopic fungal spores.

These microscopic fungal spores are present in air in large quantities. This disease is not transmittable so humans can be saved from sick dogs, it also can be seen that this disease does not transmit from dog to dog. The area where the dog is walking may release many spores in this area. These spores affect humans. The people whose immune system is very slow may want to avoid it.

Types Of Blastomycosis

There are four following types of blastomycosis.

Cutaneous blastomycosis

This is the first stage of infection and during this phase of infection patients get about 70% of this infection. This flu like symptoms also show Pox like symptoms that mean you can see bristles in the skin and there will be rashes maculopapular rashes. So, this is the first basic stage of blastomycosis.

Osteoarticular blastomycosis

This is the second stage of infection almost 10% of the individual get on this particular disease. If it is not treated earlier, it then comes to the bone level.

Now to the bone level it actually attacks several other parts of the bone like spine, femur which is the longer bone of the body and so many other bones of your body and not only affect the bone infections it also affects the soft bone and connective tissue associated with the bone. So as a result of this soft tissue attack.

So, necrosis is a disease which is seen in soft bone. The sign of necrosis is joint pain and swelling this term is known as mycotic arthritis.

Pulmonary blastomycosis

They attack the lungs and lung tissue. It causes difficulty in breathing and as a result lung can fail. There symptoms are also flu-like and also tuberculosis-like, so people many times confuse symptoms with tuberculosis. T.B like symptoms are also observed. If it remains untreated it can cause chronic lung disease RDS and COPD.

Mixed Blastomycosis

They actually can cause infection in different tissues like testes, urinary tract at the end it also causes brain abscess.

 Symptoms of Blastomycosis

The symptoms of blastomycosis are often similar to the symptoms of flu. There are following symptoms which may appear between 3 and 15 weeks after exposure.

1-      Night sweats.

2-      Weight loss.

3-      Extreme tiredness.

4-      Muscle aches.

5-      Non – reproductive Cough which determinations within days

6-      Pleuritic Chest pain.

7-      Fever.

8-      Eye discharge.

9-      Skin lesions filled with pus.

10- Eye inflammations, especially iris.

Causes Of Blastomycosis

A Fungus which has phylum Ascomycota and family ajellomycetaceae that’s name is Blastomyces dermatitidis cause blastomycosis.

This fungus lives near the river beach and lakes around the rotten woody and moist area.

This fungus is not directly observed from nature, it can be detected from their shape like cottony white mold. This fungus mostly harbors in moist and acidic soil.


Blastomycosis can be diagnosed as the adapted characteristics of tissue of budding organisms by potassium hydroxide preparation, histology, cytology. Biopsy of the tissue can be made from diagnosis. These are spherical round in shape. Blastospores are measured in 8-25 micrometers.

Granulomatous nodules are histologically connected with blastomycosis. The blastomycosis can also be diagnosis by the commercially available urine antigen test. Diagnosis can be done by taken the sample of blood or urine and then sending it in laboratory. Doctors also imagine these tests such as chest x-ray or lungs CT scans.

If the treatment process is slow then it gets numerous months (at least in most cases four to six months). However, in some cases tissues and blood cells cannot distinguish it. In certain cases, a combination of medications may be used.


Itraconazole and amphotericin B are the main drugs for the disease blastomycosis treatment. Most fungus diseases can be treated by a medicine Itraconazole.  Another medicine can also be used which is Ketoconazole.

These both medicines are given to the patient of blastomycosis disease. Treatment can get a lot of time, so preserve the medication rates high. If the patient is critically ill and has central nervous system disease, then use a medicine Amphotericin B which is highly toxic but has respectable effects.[1][2]Blastomycosis ([3]blastomycosis.pdf ([4]

Caution: All types of treatments should be after consultation of your health care or your doctor


Reviewed by:

Dr. Akhtar Nawaz Lak

MBBS, FCPS (Internal Medicine)

Ex. Medical Specialist, Services hospital, Lahore

Ex. Medical Specialist, Allied hospital, Faisalabad

Our reviewers’ details, Click Here


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3blastomycosis.pdf (

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