StudentShare
Contact Us
Sign In / Sign Up for FREE
Search
Go to advanced search...
Free

The Clinical Manifestations of Blastomycosis - Research Paper Example

Cite this document
Summary
The paper "The Clinical Manifestations of Blastomycosis" tells that blastomycosis is a systemic pyogranulomatous fungal infection that primarily affects the lungs. This disease, first described by Gilchrist in 1894, is caused by a fungus called Blastomyces dermatitidis…
Download full paper File format: .doc, available for editing
GRAB THE BEST PAPER92.9% of users find it useful
The Clinical Manifestations of Blastomycosis
Read Text Preview

Extract of sample "The Clinical Manifestations of Blastomycosis"

?American Blastocymosis Background Blastomycosis is a systemic pyrogranulomatous fungal infection which primarily affects the lungs (Longo et al., 2012). This disease, first described by Gilchrist in 1894, is caused by a fungus called Blastomyces dermatitidis (Longo et al., 2012; Varkey and Raugi, 2011). Although the clinical manifestations of blastomycosis is usually pulmonary in nature, the etiologic agent can spread hematogenously to affect other organs of the body such as the bones, gastrointestinal tract, genitourinary system, and skin, among others (Longo et al, 2012). Interestingly, blastomycosis is a disease not unique to humans. In fact, it is commonly found in dogs and has also been documented in other animals such as cats, horses, and cows (Varkey and Raugi, 2011). Etiologic Agent Blastomyces dermatitidis is the vegetative form (asexual stage) of Ajellomyces dermatitidis (Longo et al., 2012). According to Longo et al. (2012), two serotypes of the organism exist based on the presence of the A antigen. However, more recent immunologic studies using Enzyme-Linked Immunosorbent Assay (ELISA) suggests that there are perhaps more than just two serotypes (Varkey and Raugi, 2011). Nonetheless, this organism displays dimorphism, a characteristic where morphology changes based on certain environmental conditions. Specifically, for B. dermatitidis, it exists in the mycelium state at room temperature but reverts back to its yeast form when the temperature hits 37 degree Celsius (Longo et al., 2012). Under the microscope, the yeast cells appear multinucleated, with thick refractile cell walls, usually measuring 8-15 uM in diameter (Longo et al., 2011). These cells reproduce by budding. Epidemiology Most cases of blastomycosis have been documented and reported in the United States. In fact, it is endemic in the southeastern and central portions of the US, which include the Ohio River, the Mississippi River, and the Great Lakes (Varkey and Raugi, 2011). The annual incidence of the disease, based on the previously confirmed cases, is one (1) for every 100,000 people in Kentucky, Mississippi, Wisconsin, and Arkansas ( Varkey and Raugi, 2011). However, within the endemic areas, the annual incidence was reported to be as high as 40 per 100,000 individuals. It is important to note that blastomycosis is not confined in the United States. It is also distributed across Africa, Canada, Middle East, and India (Varkey and Raugi, 2011). In the US alone, a mortality rate of 5 percent among the treated cases and approximately 40 percent in the untreated individuals were recorded for blastomycosis way back in the 1960s (Varkey and Raugi, 2011). These statistics decreased in the 1990s, where the mortality rate among patients who received treatment went down to 0-2 percent (Varkey and Raugi, 2011). However, mortality among the immunocompromised individuals such as AIDS patient remains high. Mortality was documented to be as high as 40 percent. Complications caused by blastomycosis are usually rare among immunocompetent patients. Reports showed that B. dermatitidis grows in warm and moist soil in woody areas (Longo et al., 2012). Hence, exposure to soil is a common denominator among those infected with the organism. In fact, middle-aged men (mean age of 45 years old) who work outdoors were found to be at higher risk in contracting the disease (Longo et al., 2012; Varkey and Raugi, 2011). However, individuals of any age, both sexes, can get infected with the organism (Varkey and Raugi, 2011). In addition, B dermatitidis does not appear to have racial predilection. This means that the fungus can infect any individual, whatever his/ her race is. Pathogenesis B. dermatitidis enters the body by inhaling the conidia of the organism (Longo et al., 2012). Then, the conidia get deposited in the lungs, where it is usually engulfed by macrophages and other polymophonuclear leukocytes (Longo et al., 2012). However, some of the conidia that escape the body's immune defenses are converted back to its yeast state. With its thick walls and capability to produce immune-modulating virulence factor, the yeast form of B. dermatitidis offers survival advantage over its conidia counterpart, causing the infection (Varkey and Raugi, 2011. In the lungs, the yeast causes an acute pulmonary infection. However, as it multiplies and increases in number, it gets carried by the blood and lymphatics to infect other organs of the body. Signs and Symptoms Pulmonary involvement is almost always present in most cases, which manifests as abrupt onset of cough, fever, chills, myalgias, and joint pains (Longo et al.,2012; Varkey and Raugi, 2011). The cough, which is usually non- productive at the onset, eventually becomes purulent later on. The average time before pulmonary symptoms become apparent from the time the organism was inhaled is usually within 45 days (Varkey and Raugi, 2011). However, pulmonary infection may be asymptomatic in approximately 50 percent of the documented cases. In immunocompromised individuals, the body's immune system may no longer be strong enough to confine the disease within the lungs. Hence, the organism disseminates throughout the body and cause an extrapulmonary infection (Longo et al., 2012 ). Among the extrapulmonary organs affected by B. dermatitidis, the skin is the most common site of involvement (Longo et al., 2012). In fact, skin involvement occurs in as much as 20 percent of all cases (Varkey and Raugi, 2011). In few cases, the eyes, ears, nose, and trachea become affected as well (Varkey and Raugi, 2011). Diagnosis Work-up for the diagnosis of blastomycosis range from blood analysis to imaging studies (Varkey and Raugi, 2011). Complete blood count of patients with blastomycosis often present with leukocytosis with a leftward shift (Varkey and Raugi, 2011). However, this test is neither specific nor sensitive for this disease. Meanwhile, sputum microscopy offers a higher diagnostic sensitivity, which aims to visualize yeast cells in the expectorated sputum of the patient (Varkey and Raugi, 2011). The test is done by examining a sample of sputum admixed with 10 percent potassium chloride in order to visualize the organism (Varkey and Raugi, 2011). Serologic testing, where the presence of B. dermatitidis antigen and other molecular markers are identified, can also be used to diagnose blastomycosis (Longo et al, 2012). However, its utility is considered by some to be controversial because of the possibility of cross-reactivity with other fungal antigens (Longo et al., 2012). The gold standard for the diagnosis of this disease though, is made by culturing the organism from sputum or blood samples using an appropriate culture medium (Longo et al., 2012). However, this method may take some time since growth of the organism is slow. In fact, growth may be observed as early as 5 days to as late as 30 days in some cases (Varkey and Raugi, 2011). Treatment The treatment for blastomycosis, regardless of its type, is entirely medical (Longo et al., 2012). For blastomycosis, anti-fungal agents are given to patients but the choice of which anti- fungal to use is based on the clinical form of the disease, immune status of the patient, and severity of the infection (Longo et al., 2012). In general, agents such as Ketoconazole, Itraconazole, Amphotericin B, and Fluconazole can be used for the treatment of Blastomycosis. However, Itraconazole, given for 6 months, is the drug of choice for immunocompetent patients with mild to moderate pulmonary blastomycosis. For extrapulmonary cases such as bone involvement, treatment with Itraconazole is extended for a period of 12 months. Itraconazole has better bioavailability, efficacy, and less toxicity compared to other azoles (Varkey and Raugi, 2011). It must be noted, however, that any type of azole is contraindicated in pregnancy due to its teratogenic effects. Meanwhile, Amphotericin B is the first line of treatment for immunocompromised patients with blastomycosis and immunocompetent CNS blastomycosis (Longo et al., 2012). After Amphotericin B administration, Itraconazole treatment may still be needed in some cases. References Longo, D., Kasper, D., Jameson, L., Fauci, A., Hauser, S., and Loscalzo, J. 2012. Harrison' s Principles of Internal Medicine. 18th Ed. The McGraw- Hill Companies, Inc. U.S. pp 1646-1647. Varkey, B. and Raugi, G. 2011. Blastomycosis. Medscape Reference. Retrieved at: http://accessmedicine.com/content.aspx?aid=6432990. Date retrieved: April 30, 2013. Read More
Cite this document
  • APA
  • MLA
  • CHICAGO
(“Medical Microbiology American Blastomycosis Research Paper”, n.d.)
Retrieved from https://studentshare.org/health-sciences-medicine/1475534-medical-microbiology-american-blastomycosis
(Medical Microbiology American Blastomycosis Research Paper)
https://studentshare.org/health-sciences-medicine/1475534-medical-microbiology-american-blastomycosis.
“Medical Microbiology American Blastomycosis Research Paper”, n.d. https://studentshare.org/health-sciences-medicine/1475534-medical-microbiology-american-blastomycosis.
  • Cited: 0 times

CHECK THESE SAMPLES OF The Clinical Manifestations of Blastomycosis

Clinical Manifestations, Causes and Treatments for Lupus

clinical manifestations, Causes and Treatments for Lupus Deidre Jones English 201 2/21/12 Abstract Lupus is an autoimmune disease that exhibits through a wide variety of symptoms, and as a consequence can be very difficult to diagnose.... Many different parts of the body can be affected, including the skin, organs and joints....
7 Pages (1750 words) Research Paper

Islam and Its Manifestations

From the essay "Islam and Its manifestations", it is clear that Muslim people believe in the absolute truth of their faith that is perceived by Qutb as the refusal of science's acceptance.... The all mentioned aspects suggest that Islam in its various manifestations is the somewhat contradictory issue....
4 Pages (1000 words) Essay

Clinical Manifestations and Complications of Benign Prostatic Hyperplasia

This term paper "clinical manifestations and Complications of Benign Prostatic Hyperplasia" focuses on a disease that affects the prostate glands.... It is associated with the overgrowing of the periurethral prostate glands.... One ought to note that this disease is nonmalignant and adenomatous....
6 Pages (1500 words) Term Paper

Hepatic Granulomas

(1997) stated that as much as 50 to 80% of patients who are drying from tuberculosis were observed to have clinical evidence of hepatic granuloma.... 1997) For this study, the researcher will discuss the basic pathophysiology on hepatic granulomas including its etiology, pathogenesis, pathology, diagnosis, treatment, clinical features, imaging studies and the necessary clinical intervention on the said disease.... 2007) As a clinical sign or a manifestation of infection, presence of toxic substances, allergic reaction, reaction of the autoimmune system, including the presence of neoplastic diseases (Williams & Williams, 1983), the formation and development of hepatic granulomas is normally induced by the presence of a foreign body tissue such as the schistosome eggs (Van de Vijver et al....
8 Pages (2000 words) Case Study

Clinical Manifestations of Complicated and Uncomplicated Peptic Ulcer

The author analyzes the article written by Gururataskul, Holloway, Holtman, and Talley entitled "Association between clinical manifestations of complicated and uncomplicated peptic ulcer and visceral sensory dysfunction" which was published in the Journal of Gastroenterology and Hepatology....
2 Pages (500 words) Assignment

General Discussion of Respiratory Tract Infections

.... ... ...
7 Pages (1750 words) Assignment

Clinical Manifestation, Diagnostic Criteria and Psychopathology of Schizophrenia

"clinical Manifestation, Diagnostic Criteria, and Psychopathology of Schizophrenia" paper evaluate a case study of a schizophrenic patient.... Schizophrenia is a serious, complex, and disabling mental illness that is associated with significant impairment in social and vocational functioning....
15 Pages (3750 words) Case Study

Cystic Fibrosis - Pathophysiology and Pathogenesis

The paper 'Cystic Fibrosis – Pathophysiology and Pathogenesis, Prevalence, clinical Manifestation, Diagnosis, and Treatment' is an exciting example of a literature review on health sciences & medicine.... The paper 'Cystic Fibrosis – Pathophysiology and Pathogenesis, Prevalence, clinical Manifestation, Diagnosis, and Treatment' is an exciting example of a literature review on health sciences & medicine.... Therefore, it is necessary to discuss the literature about the disease, through the topics of pathophysiology and pathogenesis, prevalence, clinical manifestation, diagnosis, treatment and making comparisons of the old and new studies....
8 Pages (2000 words) Literature review
sponsored ads
We use cookies to create the best experience for you. Keep on browsing if you are OK with that, or find out how to manage cookies.
Contact Us