Protothecosis: Pseudofungal Infection Caused By Algae

It is frightening to think there are tons of fungi that can cause infections, but to make matters worse, there is a class of organisms that cause infections similar to fungi and are not fungi.  In this blog I have presented many fungal infections, but for this post I will present an interesting infection cause by a pseudofungus that is uncommon but important to know nonetheless.  This infection is called protothecosis.


General Description:
Protothecosis is an infection caused by achlorophyllic algae in the genus Prototheca.  These algae normally do not infect humans and people who do get infected usually have a compromised immune system.  This algae is present in all continents in the world and infects dogs and cattle more often than people.  The parasite is acquired by coming in contact with contaminated water or soil and usually enters the body through an injury on the skin.  There are three forms of infection that can be acquired from this parasite: cutaneous infection, olecranon bursitis, and systemic infection.  Antifungal medication is commonly used to treat this condition with success, but there is no definite treatment to this condition as it is rare and uncommon.

Locations:
This infection is present throughout the world and can be on any unsanitary object like soil, water, animals, etc.  Taiwan has higher cases of this infection in the rural areas.

Infection Method:
The transmission of the parasitic algae is uncommon, but can happen through injury with an infected object.  The parasite then spreads and can cause one of the three conditions as mentioned in the general description.  It is difficult to know when the infection was acquired because the incubation period for this parasite is not well documented.  Weeks and months can pass before symptoms show and patients will not remember the injury that introduced the algae into the body.  This infection is not contagious between people.

Symptoms:
There are three types of infections that are associated with protothecosis and these vary depending on the patient.
Cutaneous infection.  This is caused when the parasite just invades the skin.  It is characterized by common skin infections symptoms like nodules, ulcers, papules, lesions, and pustules.  About half of the cases of protothecosis are cutaneous infections. 
Olecranon Bursitis.  This infection is a swelling of the tip of the elbow.  It is believed this occurs when the elbow is grazed on material infected with the Prototheca algae.  The symptoms begin to show weeks after the injury.  This condition is not exclusively caused by protothecosis and is unclear why the parasite can cause this condition.  Symptoms include swelling of the skin and tenderness, followed by production of serosanguinous fluid.
Systemic infection.  This condition occurs when the parasite infects immuno-compromised individuals and can be the more dangerous one.  People who are receiving cancer treatment, received and organ transplant, or have AIDS are at risk of developing this condition.  The parasite can infect subcutaneous tissue, gut, spleen, and blood.  Symptoms include fever, chills, sepsis syndromes, and hepatic inflammatory diseases.

Treatment:
This parasite needs to be diagnosed with microbial tests like tissue samples and stains.  This explains why it is difficult to diagnose it early.  Once diagnosed, there are antifungal medications that have proven to be effective.  This condition is still under research, but more and more medications and treatments are being developed to better prepare for this infection.

Final Thoughts:
When people think of parasites, I do not think most people would think algae can cause infections like parasitic infections.  Algae is present across the globe and just about any damp surface allows for algae to grow.  Also, most algae is microscopic, so we cannot be sure if a surface has them or not.  That fact that the algae that causes protothecosis can be on any surface means people need to be mindful of when they get injured.  I know people that ignore small injuries when they happen, but based on the research I have done, I advise that it would be a great idea to remember when and how you receive lesions.
For people that are traveling or hiking or even just gardening, make sure to cover your skin and if you do get injured in the form of a lesion, remember that it happened.  I am not saying to go to the doctor every time you get a splinter, but reading about many infections like the content of my blog can help you diagnose yourself if you suspect you have an uncommon parasitic infection.
I hope you all enjoyed this post! Leave a comment or recommendation about any interesting parasitic infection.

References:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1865593/
http://www.assh.org/handcare/hand-arm-conditions/olecranon-bursitis