Microsporidia are a group of obligate intracellular organisms that were recently reclassified as fungi Fungi A kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including mushrooms; yeasts; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies. Mycology. Microsporidia is made up of around 15 clinically relevant species, with the most common being Enterocytozoon bieneusi. There is much we do not understand about this group of organisms, and knowledge is evolving. Microsporidia species are ubiquitous, with a wide range of reservoirs. Immunocompromised immunocompromised A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation. Gastroenteritis individuals (particularly those with AIDS AIDS Chronic HIV infection and depletion of CD4 cells eventually results in acquired immunodeficiency syndrome (AIDS), which can be diagnosed by the presence of certain opportunistic diseases called AIDS-defining conditions. These conditions include a wide spectrum of bacterial, viral, fungal, and parasitic infections as well as several malignancies and generalized conditions. HIV Infection and AIDS and a CD4 count < 100 cells/µL) most commonly develop symptomatic microsporidiosis. GI diseases range from acute, self-limited watery diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea to chronic diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea causing malabsorption Malabsorption General term for a group of malnutrition syndromes caused by failure of normal intestinal absorption of nutrients. Malabsorption and Maldigestion and wasting. Extraintestinal manifestations and dissemination can also occur, affecting the eyes, respiratory tract, brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification, biliary tract Biliary tract Bile is secreted by hepatocytes into thin channels called canaliculi. These canaliculi lead into slightly larger interlobular bile ductules, which are part of the portal triads at the "corners" of hepatic lobules. The bile leaves the liver via the right and left hepatic ducts, which join together to form the common hepatic duct. Gallbladder and Biliary Tract: Anatomy, urinary tract Urinary tract The urinary tract is located in the abdomen and pelvis and consists of the kidneys, ureters, urinary bladder, and urethra. The structures permit the excretion of urine from the body. Urine flows from the kidneys through the ureters to the urinary bladder and out through the urethra. Urinary Tract: Anatomy, and/or muscles. Diagnosis occurs through identification Identification Defense Mechanisms of spores Spores The reproductive elements of lower organisms, such as bacteria; fungi; and cryptogamic plants. Anthrax on examination of the stool. Antimicrobials, such as albendazole Albendazole A benzimidazole broad-spectrum anthelmintic structurally related to mebendazole that is effective against many diseases. Anthelmintic Drugs and fumagillin, can be used to treat infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease with most microsporidia species.
Last updated: Jun 14, 2022
Microsporidiosis is caused by approximately 15 species, including:
Microsporidia have an extensive range of reservoirs, including (but not limited to):
Though mild or subclinical disease may occur in immunocompetent individuals, most symptomatic infection occurs in those who are immunocompromised immunocompromised A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation. Gastroenteritis:
Transmission of microsporidia is not fully understood, but possibilities include:
The pathophysiology is not completely understood.
The clinical presentation of microsporidiosis depends on:
Sign up now and get free access to Lecturio with concept pages, medical videos, and questions for your medical education.
Lecturio Premium gives you full access to all content & features
Verify your email now to get a free trial.
Lecturio Premium gives you full access to all contents and features—including Lecturio’s Qbank with up-to-date board-style questions.