Originally thought to be a type of fungus, Mycoplasma has been reclassified as a genus of bacteria that lack a cell wall. Over 100 species have been categorized, many of which are parasitic, feeding and proliferating off vertebrate hosts. Others absorb nutrients from decomposing organic matter. Several Mycoplasma human pathogens have been identified, including Mycoplasma pneumonia and Mycoplasma genitalium, which can cause pneumonia and urinary tract infections, respectively.
Characteristics
Categorized as the smallest known organism able to live independently of a host, although many types are parasitic, Mycoplasma is a tiny microorganism. It's about 1/10 the size of E. coli bacteria. Mycoplasma have a unique cell membrane that's highly deformable and contains molecules known as sterols, such as cholesterol. They aren't present in other bacteria or viral cell membranes, according to the Centers for Disease Control and Prevention.
Antibiotic Resistance
Common types of antibiotics such as penicillins, cephalosporins and other members of the beta lactam family exert their antibacterial actions by interfering with the process bacteria use to form cell walls. Mycoplasma does not have a cell wall, and is therefore resistant to these types of antibiotics, according to a July 2005 article published in the Cochrane database of Systemic Reviews Online.
Pathophysiology
Some types of Mycoplasma can cause human infections by binding to types of epithelial cells, predominantly in the respiratory tract and urinary or genital tracts. These pathogens damage the body by excreting toxic chemicals such as hydrogen peroxide, and by stimulating the body to attack itself in a process known as antibody mediated autoimmunity, according to a February 2008 article published in "Clinical Microbiology and Infection."
Mycoplasma Pneumonia
One disease causing species of Mycoplasma is Mycoplasma pneumonia, which is transmitted through inhalation of infested water droplets dispersed by coughs and sneezes from infected people. Onset of symptoms typically occurs two to three weeks after initial exposure to the pathogen and includes muscle pain, sore throat, persistent cough, raised temperature and pneumonia in approximately 10 percent of cases, according to an August 2002 article published in the European Journal of Clinical Microbiology and Infectious Diseases.
Mycoplasma Genitalium
Diseases of the urinary and genital tracts are caused by Mycoplasma genitalium, as well as several other species of Mycoplasma. These pathogen can be transmitted during unprotected sexual intercourse. This leads to urinary tract infection, vaginal itching and pelivic inflammatory disease, according to a March 2006 article published in "Sexually Transmitted Infections."
References
- "Clinical Microbiology and Infection"; Mycoplasma Pneumoniae-an Emerging Extra-Pulmonary Pathogen; F. Sanches-Vargas, G. Gómez-Duarte; February 2008
- "European Journal of Clinical Microbiology and Infectious Diseases"; Emerging Role of Mycoplasma Pneumoniae in Children with Acute Pharyngitis; S. Esposito et al.; August 2002
- "Cochrane database of Systemic Reviews Online"; Antibiotics for Community Acquired Lower Respiratory Tract Infections (LRTI) Secondary to Mycoplasma Pneumoniae in Children; J. Gavranich, A. Chang A; August 2002
- Centers for Disease Control and Prevention: Mycoplasmas: Sophisticated, Reemerging, and Burdened by Their Notoriety
