Medical Mycology Module (3130) Essay: Coccidioides immitis Introduction Coccidioides spp is a dimorphic fungus endemic in parts of the Western hemisphere causing a range of disease from asymptomatic infection to fatal disseminated disease. This review focuses upon its taxonomy, species identification, pathophysiology, investigation, treatment and prevention. Taxonomy Coccidioides is classified into two species, C. immitis and C. posadasii, which are distinct genetically and in geographic range but are otherwise identical. (1). It is closely related to the non-pathogenic soil fungus Uncinocarpus reesii. (2) Currently Coccidioides is classified in the division Ascomycota, class Dikaryomycota, order Onygenales and family Onygenaceae. (3) Ecology C. immitis is found preferentially in alkaline sandy clay soils in warm dry climates with a high salt content between 10-30cm below the surface.(4, 5) It’s distribution through the soil is patchy, concentrated around animal burrows or soils rich in nitrogen containing animal excreta, persisting for extended periods in the environment.(5) Species identification C. immitis is non-fastidious growing on a variety of culture media including brain-heart infusion agar, potato-dextrose agar, Sabourand-dextrose agar and blood agar. (3) Culture to induce mycelial growth is best at 28-30oC typically taking 2-3 weeks with growth detectable within 5 days. (3, 6, 7) The colony is initially white and glabrous, quickly becoming floccose resembling angel hair (see picture 1) and turning brown as it ages. (3, 6) Microscopically the culture shows single celled barrel-shaped alternate arthroconidia (see picture 2) separated from each other by a disjunctor cell.(6, 8) Conversion to the yeast / spherule form re... ... middle of paper ... ...unity against Coccidioides. (3) This is no longer performed in the USA. (3) Coccidioides infection can be demonstrated by an antigen based ELISA using Coccidioides galactomannan. When performed upon urine a sensitivity of 71% and specificity of 99% was demonstrated. (26)The test performed best in patients with severe forms of the disease. Cross reactions with other endemic mycoses occurred in 10% of patients. (26) Real time polymerase chain reaction (PCR) targeting the Coccidioides internal transcribed spacer 2 (ITS2) and Antigen 2/proline rich antigen gene (Ag2/PRA) have been developed. When applied to respiratory tract and cerebrospinal fluid samples, they offer a sensitivity of up to 100% and a specificity of up to 98% and a short time to diagnosis. (30) Current PCR assays are predominantly in house or reference laboratory tests and not commercialised. Treatment
Sordaria fimicola belongs to the kingdom of fungi and is part of the phylum Ascosmycota. This fungus habitat is in the feces of herbivores. As many fungi Sordaria have one life cycles which is haploid/ diploid. It is commonly exits as a haploid organism, but when the mycelium from two individuals meets, the result is a diploid zygote. This diploid zygote which undergoes meiosis forms eight haploid ascospores . The ability of Sordaria to make 8 haploid ascospores is what makes it unique and important for the laboratory exercise done in lab.
After 5 days of growth each slant was tested using the gram staining technique to confirm the complete isolation of the bacteria. Both isolations were completely successful. Then each sample of bacteria was subjected to a series of tests for identification.
Puechmaille, S.J. 2010. "White-Nose Syndrome Fungus in Bat, France". Emerging Infectious Diseases. 16 (2): 290-293.
Catlin (1992) reports that many different media have been used to isolate G. vaginalis from clinical specimens. The most successful media pos...
For medical care, no treatment is needed for those who are asymptomatic, just monitoring for mild symptoms (2). For those who cannot fight the disease as easily as the majority, there are an array of treatments available. To start, blood cultures should be performed in all patients, and sputum cultures should be taken for those with chronic histoplasmosis (2). Chest radiology would be preferred for individuals with acute pulmonary histoplasmosis, steroids and possible laser treatment for ocular histoplasmosis, and CT scans for those with cerebral histoplasmosis (2). With prolonged symptoms of more than 4 weeks, medical therapy via itraconazole is recommended for 6-12 weeks, followed by chest imaging (2). Bronchiectasis caused by the microbe is treated with either a bronchoscopy or surgical removal (3). Phrenological treatments to histoplasmosis include amphorcetericin B, ketoconazole, itraconazole, and fluconazole (3). Currently, antifungal agents are being developed to offer alternative treatment (3). To successfully survive as a pathogen, the virus must change itself on a micro level to survive changing conditions, macrophages, and other threats to the fungi’s reproduction (4). Being able to go from an environmental mold to an intercellular yeast is extremely useful for a microbe in an ecosystem that fights for control of those it infects (4). These advantages present within histoplasmosis are what keeps it as a cause of respiratory and systemic disease in mammals (4). There are plenty of treatments available to accommodate all forms of histoplasmosis, making it a microbe that is very simple to cure, despite how hard it tries to
The pancreas can be divided into two sections when studying the histology. The pancreas has exocrine and endocrine functions, each with unique cell types. The exocrine pancreas serves to secrete digestive enzymes into the duodenum. Some of the specific enzymes and secreted substances are Proteases, lipase, amylase, bicarbonate, and water (Bowen, “Exocrine Secretions”). These enzymes are used to break down protein, fat, and carbohydrates respectively. The bicarbonate simply act as an acid buffer to prevent damage of the small intestine as the stomach acid must be neutralized. The enzymes are created in acinar cells and the bicarbonate is synthesized in epithelial cells surrounding pancreatic ducts (Bowen “Exocrine
Also known as Coccidioidomycosis, Valley fever infections have been on the rise in recent years. Endemic to the desert Southwest, valley fever is caused by the soil-dwelling fungus Coccidioides. The cocci get stirred up by building, drilling, tilling, and clearing land, and disperse due to dry, hot, windy conditions. The spores may be inhaled and are capable of embedding deep into the lungs.
Valley fever is a fungal pathogen. Coccidioidomycosis is valley fever’s scientific name. The pathogen’s structure is a spore. Valley fever is caused by Coccidioides immitis. Coccidioides immitis is a fungus that grows in soil. Valley fever is most commonly found in areas with little precipitation. This pathogen is most commonly found in the southern United States, Central America, and South America. However, scientists are worried that increased temperatures may cause valley fever to spread and affect new areas.
"Bloodborne Pathogens : MedlinePlus Medical Encyclopedia." U.S National Library of Medicine. U.S. National Library of Medicine, n.d. Web. 09 Feb. 2014.
Coccidioides is a pathogen that is part of the fungal kingdom (Taxonomy Browser). The separation of the species immitis and posadasii has been a relatively new discovery. The separation has allowed the study of these species in different locations in the United States and Central and South America, as well as the migration of these species throughout the North and South American continents (Lewis et al, 2). The entire taxonomic
Coccidioides immitis is a fungi that normally grows in the soil. This fungi is dimorphic so it exist in two different forms. The form that grows in the soil is called the saprophytic form. It can also exist in a parasitic form if it enters a host. C. immiti can cause a disease called valley fever in humans if it is inhaled (Coccidioides, 2010).
Microbe-specific diagnosis, based on culture of blood, fluid or samples obtained directly from the focus of infection in the lungs, is possible only in a small minority of CAP cases. In papers published over the last 15 to 20 years, serological tests based on antigen, antibody and immune complex detection have been used for microbe-specific diagnosis of CAP in children (39, 43).
C. malina has grayish-black mycelium. However, no conidia have been observed in this fungus. Researchers have not observed either asexually reproductive or sexually reproductive structures both in the field and in laboratory conditions. The attempt to induce production of reproductive structures by Tomaso-Peterson et al.in 2016 was not successful (Tomaso-Peterson et al. 2016). Other species in the Curvularia genus do produce reproductive structures. Production of conidia and spores has been observed in Curvularia inaquaelis (Kim et al. 2000).
Microbes are everywhere in the biosphere, and their presence invariably affects the environment in which they grow. The effects
moniliformis is found primarily in rats flora of their upper respiratory tract. In cultures, the organism is found in the nasopharnyx, larynx, upper trachea, and middle ear. The bacteria can be contracted by bite, handling of the rodent or by exposure to its excreta or saliva. S. moniliformis is also found in mice, guinea pigs, gerbils and ferrets.