Algaemia is a secondary term that refers to the emerging condition in which green algae enter the bloodstream. Members of the genus Prototheca are the most common algae that leads to algaemia. Prototheca and Chlorella , which is extremely rare, are the only two known algae genera capable of inflicting disease on mammals, including humans, through invasion of host tissue. [1] The majority of cases are observed in dairy cattle as a cause of bovine mastitis as well as other domesticated animals. Cases of algaemia have been observed in dogs and cats as well. [2] Few cases have been observed in humans. Human cases of protothecosis are examined on a case-by-case basis due to the particularity of each case. Protothecosis infection is classified based on the symptoms: (i) cutaneous lesions, (ii) olecranon bursitis, and (iii) disseminated or systemic type infections. [3]
Protothecosis can affect anyone but is most commonly seen with more severe symptoms in those who have preexisting conditions. Individuals with a weak immune system have been shown to experience the worst symptoms. Many symptoms are not specific to this infection and can be hard to differentiate. Prototheca is not included as a typical infection that is screened for and is usually not identified without examination by microscope. Polymerase chain reaction tests have shown to assists in the identification of Prototheca. Symptoms include but are not limited to: numbness in the extremities, olecranon bursitis or general inflammation, cutaneous infections in the hair, skin or fingernails, skin lesions, difficulty breathing, respiratory failure, multiple organ failure, and can result in death if not treated in the early stages of infection. [4]
The algal cells are commonly found in the soil and water of many regions. Prototheca, especially P. wickerhamii and P. zopfii, can colonize the skin, fingernails, respiratory and digestive tracts. Prototheca algae cells can enter the bloodstream through open wounds, mucous membrane pathways, or the ingestion or inhalation of the cells. Individuals who are immunocompromised begin to see more concerning symptoms as the cells build up within the bloodstream. [3]
This section is empty. You can help by adding to it. (April 2022) |
Treatments for human protothecosis can range from pharmaceutical to surgical efforts. Anti-fungal medications such as ketoconazole, itraconazole, and amphotericin B are commonly given drugs for treatment. Amphotericin B has proven to be the most effective but failure to treat or cure is not uncommon. Surgery is an option in some cases but is only when the infection remains localized in an area that can be excised. [3]
Prototheca is a genus of algae first identified by Wilhelm Krüger in 1894. Krüger first classified Prototheca as fungi. It was later reclassified as algae. It is believed that this genus of algae began with photosynthetic ability but over time transitioned to a parasitic form. Unlike most algae, prototheca cells lack chlorophyll and instead rely on a host for nutrients. [3] Two groups within Prototheca have been identified: those typically associated with cattle (P. ciferrii and P. bovis), and those considered human-associated (P. wickerhamii, P. zopfii, and P. miyajii). P. wickerhamii and P. zopfii are the predominant algae associated with algaemia. [5] Prototheca can exist in a variety of environments but have been found frequently in warm and humid regions. This specific algae is more prevalent in the southern and southeastern portions of the United States as well as regions of northeastern Australia, southern portions of Europe, and Japan. The algal cells have been identified in samples from sewage, fresh and saltwater, animal feces, and some foods. [2]
Coccidioidomycosis, is a mammalian fungal disease caused by Coccidioides immitis or Coccidioides posadasii. It is commonly known as cocci, Valley fever, as well as California fever, desert rheumatism, or San Joaquin Valley fever. Coccidioidomycosis is endemic in certain parts of the United States in Arizona, California, Nevada, New Mexico, Texas, Utah, and northern Mexico.
Histoplasmosis is a fungal infection caused by Histoplasma capsulatum. Symptoms of this infection vary greatly, but the disease affects primarily the lungs. Occasionally, other organs are affected; called disseminated histoplasmosis, it can be fatal if left untreated.
Cryptococcosis is a potentially fatal fungal infection of mainly the lungs, presenting as a pneumonia, and in the brain, where it appears as a meningitis. Coughing, difficulty breathing, chest pain and fever are seen when the lungs are infected. When the brain is infected, symptoms include headache, fever, neck pain, nausea and vomiting, light sensitivity and confusion or changes in behavior. It can also affect other parts of the body including skin, where it may appear as several fluid-filled nodules with dead tissue.
Microalgae or microphytes are microscopic algae invisible to the naked eye. They are phytoplankton typically found in freshwater and marine systems, living in both the water column and sediment. They are unicellular species which exist individually, or in chains or groups. Depending on the species, their sizes can range from a few micrometers (μm) to a few hundred micrometers. Unlike higher plants, microalgae do not have roots, stems, or leaves. They are specially adapted to an environment dominated by viscous forces.
Chromoblastomycosis is a long-term fungal infection of the skin and subcutaneous tissue.
Protothecosis, otherwise known as Algaemia, is a disease found in dogs, cats, cattle, and humans caused by a type of green alga known as Prototheca that lacks chlorophyll and enters the human or animal bloodstream. It and its close relative Helicosporidium are unusual in that they are actually green algae that have become parasites. The two most common species are Prototheca wickerhamii and Prototheca zopfii. Both are known to cause disease in dogs, while most human cases are caused by P. wickerhami. Prototheca is found worldwide in sewage and soil. Infection is rare despite high exposure, and can be related to a defective immune system. In dogs, females and Collies are most commonly affected.
Pythiosis is a rare and deadly tropical disease caused by the oomycete Pythium insidiosum. Long regarded as being caused by a fungus, the causative agent was not discovered until 1987. It occurs most commonly in horses, dogs, and humans, with isolated cases in other large mammals. The disease is contracted after exposure to stagnant fresh water such as swamps, ponds, lakes, and rice paddies. P. insidiosum is different from other members of the genus in that human and horse hair, skin, and decaying animal and plant tissue are chemoattractants for its zoospores. Additionally, it is the only member in the genus known to infect mammals, while other members are pathogenic to plants and are responsible for some well-known plant diseases.
Nakaseomyces glabratus is a species of haploid yeast of the genus Nakaseomyces, previously known as Candida glabrata. Despite the fact that no sexual life cycle has been documented for this species, N. glabratus strains of both mating types are commonly found. N. glabrata is generally a commensal of human mucosal tissues, but in today's era of wider human immunodeficiency from various causes, N. glabratus is often the second or third most common cause of candidiasis as an opportunistic pathogen. Infections caused by N. glabratus can affect the urogenital tract or even cause systemic infections by entrance of the fungal cells in the bloodstream (Candidemia), especially prevalent in immunocompromised patients.
Prepatellar bursitis is an inflammation of the prepatellar bursa at the front of the knee. It is marked by swelling at the knee, which can be tender to the touch and which generally does not restrict the knee's range of motion. It can be extremely painful and disabling as long as the underlying condition persists.
Olecranon bursitis is a condition characterized by swelling, redness, and pain at the tip of the elbow. If the underlying cause is due to an infection, fever may be present. The condition is relatively common and is one of the most frequent types of bursitis.
Prototheca is a genus of algae in the family Chlorellaceae. While this genus is a member of the green algae, all Prototheca no longer have chloroplasts and therefore their photosynthetic ability. Some species can cause protothecosis in humans and various vertebrates.
Protozoan infections are parasitic diseases caused by organisms formerly classified in the kingdom Protozoa. These organisms are now classified in the supergroups Excavata, Amoebozoa, Harosa, and Archaeplastida. They are usually contracted by either an insect vector or by contact with an infected substance or surface.
Prototheca wickerhamii is a ubiquitous green alga that does not have chlorophyll. It is widely present in the environment but is a rare cause of opportunistic infection in humans (protothecosis).
In biology, a pathogen, in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ.
Apophysomyces variabilis is an emerging fungal pathogen that can cause serious and sometimes fatal infection in humans. This fungus is a soil-dwelling saprobe with tropical to subtropical distribution. It is a zygomycete that causes mucormycosis, an infection in humans brought about by fungi in the order Mucorales. Infectious cases have been reported globally in locations including the Americas, Southeast Asia, India, and Australia. Apophysomyces variabilis infections are not transmissible from person to person.
Prototheca zopfii is an ubiquitous achlorophyllic green alga. It is a known cause of mastitis in cattle.
Histoplasma duboisii is a saprotrophic fungus responsible for the invasive infection known as African histoplasmosis. This species is a close relative of Histoplasma capsulatum, the agent of classical histoplasmosis, and the two occur in similar habitats. Histoplasma duboisii is restricted to continental Africa and Madagascar, although scattered reports have arisen from other places usually in individuals with an African travel history. Like, H. capsulatum, H. duboisii is dimorphic – growing as a filamentous fungus at ambient temperature and a yeast at body temperature. It differs morphologically from H. capsulatum by the typical production of a large-celled yeast form. Both agents cause similar forms of disease, although H. duboisii predominantly causes cutaneous and subcutaneous disease in humans and non-human primates. The agent responds to many antifungal drug therapies used to treat serious fungal diseases.
Phialophora verrucosa is a pathogenic, dematiaceous fungus that is a common cause of chromoblastomycosis. It has also been reported to cause subcutaneous phaeohyphomycosis and mycetoma in very rare cases. In the natural environment, it can be found in rotting wood, soil, wasp nests, and plant debris. P. verrucosa is sometimes referred to as Phialophora americana, a closely related environmental species which, along with P. verrucosa, is also categorized in the P. carrionii clade.
Chlorellosis is a disease caused by the infection of Chlorella, a type of microalgae containing large amount of chloroplasts. It is mainly found in sheep and cattle, while cases in humans, dogs, antelopes, beavers, camels and fish, were also reported. Symptoms of Chlorellosis including focal cutaneous lesions, lymphadenitis, and peritonitis.
Subleukemic leukemia, also known as leukemia subleukemic and aleukemic leukemia cutis, is a rare, cancerous blood disease characterized by the presence of abnormal or atypical white blood cells in the peripheral blood while the total white blood cell count is within the normal range. It can also be characterized by leukemic cells in the skin and subcutaneous tissue which can manifest as visible lesions that are known as cutaneous lesions. Subleukemic leukemia has the same treatment plans as leukemia, including chemotherapy and radiation treatments.