Coccidioidomycosis Valley Fever - Research Paper Example

Coccidioidomycosis (Valley Fever) Introduction Coccidioidomycosis, or valley fever, is a disease that normally affects one’s lungs. Coccidioides cause the illness, which is a fungus. A hardy strain of this fungus has the ability to live for long under harsh conditions like drought and extreme heat and cold (Williams 41). It is spread through the air when its spores are disturbed by wind. It is estimated that 150,000 infections take place annually in the US, although roughly half of this do not present any symptoms. The fungus is found in South America, Central America, Mexico, and South Western US since these areas weather conditions and dust that allows for the growth of Coccidioides. People get this illness when they inhale dust that contains the spores of this fungus. This spores spread into the air when dust containing the fungus undergoes disturbance through construction work, digging, or strong winds (Williams 41). The illness is hard to prevent, and no vaccine exists at present, although efforts towards its development are continuing. This research paper seeks to use journal articles and boos to discuss the epidemiology, pathogenesis, types, diagnosis, treatment, complications, and use in biological warfare of Coccidioidomycosis. Region of Primary Location The map provided below shows areas in the Americas where mass testing has revealed valley fever as an endemic illness. Taking note of the fact that two thirds of cases in the United States are found in Arizona with Tucson and Phoenix being the most affected is essential. In California, the endemic area is Kern County (Tabor 27). There are also areas of high endemic occurrences in Northwestern Mexico, South America, and Central America. In addition, it has been known for environmental conditions to spread spores across hundreds of miles and cause infection. The mass testing that identified the primary areas has not been done again for more than 50 years. Valley fever is restricted to America with an approximated 150,000 infections every year with the infection rates in the rest of the Americas currently unknown (Tabor 27). Approximately 25,000 new cases annually in the US lead to ~75 deaths annually. There are occasional epidemics with case numbers rising in Arizona, which may be related to people immigrating there. Outside of the United States, the most affected nations are Argentina, Paraguay, Brazil, Guatemala, and Mexico. (Williams 18) Epidemiology Valley fever is confined to areas that lie between 400N and 400S. The organism is particularly supported by dry and dusty soils in the lower sonaran life zone. Incidences of the organism’s occurrence increases significantly in periods where there is heavy rain followed by dry periods (Einstein & Catanzaro 23). The fungus is known to infect majority of the mammals, especially cats, dogs, and humans. Species such as marine mammals like the sea otter, llamas, and livestock have been found to be especially vulnerable to the valley fever fungus. Pathogenesis The valley fever fungus exists in the form of filaments in lab environments and soil. Cells that are found within the hyphae, over time, degenerate and form arthroconidia that are barrel shaped cells (Stevens 1079). These cells are light in weight and are transported by wind where they are easily inhalable sans knowledge of the individual. Once these cells arrive in the individual’s alveoli, they become larger, developing internal septations, whose structure is referred to as spherule and develop into endospores. Once these spherules rupture, the endosperms are released with the cycle being repeated, spreading a local infection. The nodules that at times form around the spherules could rupture, and their contents released, into the bronchus, to form cavities with thin walls. These cavities led to persistent coughs, haemoptysis, and chest pain (Stevens 1079). In people whose immunity is compromised, this infection could spread through the vascular system. Presentation Valley fever tends to mimic atypical pneumonia, influenza, or cold. Approximately 60% of those with valley fever are asymptomatic and, for those who get sick, 65% develop a mild fever with temperatures of around 390C-40.50. For about five days, the patient feels; chest pains with severe pain to mild constrictions, dry coughs that are not productive, arthralgiain of peripheral or back joints, and severe postorbital or mild frontal headaches like those in malaria (Ioachim & Medeiros 34). Symptomatic cases normally present as influenza with coughs, rash, headaches, and myalgia. In this case, the rash presented is maculopapular. Necklace like erythema multiforme and lower extremity erythema nodosum predominates in women. There are those patients who do not recover and get widespread disseminated infection that afflicts the bone, joints, soft tissues, and meninges, as well as chronic pulmonary infection (Ioachim & Medeiros 34). Where the victim is immune-compromised, there may be development of severe pulmonary disease. Types of Coccidioidomycosis Pulmonary cutaneous valley fever presents as a skin disease that result from Coccidioides immitis after inoculation history or the finding of colonized splinters in lesions on the skin (Pappagianis 222). It is a clinical condition that is rare and which can be wrongly diagnosed as leprosy or tuberculosis. It presents as subcutaneous abscess, intact granules, verrucous granuloma, and ulcers. Its prevalence stands at 0.5% and, therefore, it requires a high degree of suspicion so as diagnose the disease in its cutaneous form. Primary pulmonary Coccidioidomycosis results from the inhalation of the fungus Coccidioides immitis. When pulmonary symptoms decrease, approximately 15% of men and 30% of women present with manifestations of allergic skin of the erythema nodosum form (Pappagianis 222). Coccidioidoma presents after pulmonary Coccidioidomycosis and is a localized and benign granulomatous scar or lesion that persists in the lung tissue. Finally, disseminated Coccidioidomycosis is the third form of valley fever and is a systemic infection of the fungus where approximately 20% of people present with skin lesions (Galgiani 1219). It is a fungal infection, which is carried through the vascular system with the involvement of numerous organs. Diagnosis Valley fever infection is seen through a microscope that can detect diagnostic cells in biopsy tissue, sputum, exudates, and body fluids through such methods as methenamine Ag staining (Kauffman 34). The stains demonstrate inflammation that surrounds the spherules. Using PCR, the DNA of Coccidioidomycosis immitis can be amplified with nucleotide primers. Morphological identification can also be carried out in culture, as well as the use of molecular probes to hybridize with the fungus’ RNA. The fungus for valley fever can only be distinguished from Coccidioidomycosis immitis in cytology by the use of DNA PCR. Indirect fungal infection demonstrations can also be done, through serologic analysis, to detect antibodies produced in response to the fungus’ intrusion. Tests that are available for detecting the virus include enzyme immunoassays, complement fixation assays and TP assays (Kauffman 35). However, the latter’s antibody is absent in cerebral-spinal fluid and its antibody is specific, making it appropriate for confirmation tests with ELISA used for screening due to its sensitivity. X-rays of the chest normally show nodules of less than 4cm in diameter, in the lungs’ upper lobes that do not calcify in ordinary conditions. CSF presents with extremely low levels of glucose if meninges are affected. Treatment There have been few clinical trails to assess outcomes of the illness in its less severe outcomes since most of the infections resolve sans any particular therapy. Most recommendations for treatment are representative of consensus guidelines, which have their basis on experience of investigators and Mycosis study group trials (Sellon & Long 12). There is general disagreement on those who should be treated, the agents that should be utilized, and the length of the treatment. Before any valley fever case is treated, several questions are asked of the condition. Is it necessary to intervene? If intervention is necessary, which agents would be appropriate? Is it necessary to carry out a surgical procedure for reconstruction and debridement of destructive scars or lesions? In making these decisions, the physician pays increased attention to dissemination risk factors like age, ethnicity, and race, severity of infection, presence of severe co-morbidity like negative skin results, pregnancy, and diabetes, and serum complement fixation (Sellon & Long 13). Mild cases do not need treatment. IV Amphotericin B and Fluconazole are utilized in disseminated or progressive disease and in cases where the immunity of patients is compromised (Sellon & Long 16). Itraconazole can also be used. In the case of coccidioidal meningitis, Fluconazole is preferred because it can enter into the CSF. IV Amphotericin B can be used where there is persistence of the infection following treatment with Fluconazole. Voriconazole can also be utilized, as can Posaconazole. Currently, there is no vaccine for those who are in areas that have a high prevalence of valley fever (Sellon & Long 16). Instead, they are asked to avoid inhalation of dust, for instance, by wearing facemasks. Complications Valley fever has various complications. One of them is severe pneumonia with most individuals recovering from valley fever-related pneumonia sans any complication. However, Asian, Native Americans, blacks, Hispanics, and Filipinos may present with serious illness. Another complication is ruptured lung nodules (Hagan et al 15). Approximately 5% of individuals develop cavities that are thin-walled in their lungs, which normally disappear sans any problems. However, some rupture to cause difficulty in breathing and chest pains. Ruptured lung nodules may need a tube to be placed in the space surrounding the lungs to remove air, or even surgery that seeks to repair the resultant damage. Finally, disseminated disease is another complication, which is the most serious. If the fungus disseminates in the body, various problems like meningitis, UTI problems, and inflammation of the heart, joint pains, bone lesions, abscesses, and skin ulcers may result (Hagan et al 17). Biological Warfare Coccidioides posadasii and Coccidioides immitis are fungi that have the ability to cause diseases that are life threatening in otherwise healthy people (Drutz & Catanzaro 729). Even self-limited disease is associated with a significant morbidity. Inhalation of one spore is enough to lead to lethal infection, and this was responsible, to a degree, for the USSR and the USA developing programs to turn it into a biological weapon. It was hoped that the fungus could be used as an incapacitant, although later medical epidemiology clarified that it would be lethal on specific population segments, which saw it labeled a lethal agent, ensuring it never reached the standardization stage (Drutz & Catanzaro 730). While it went through a number of trials, the fungus was not incorporated as a weapon. Works Cited Drutz, David. & Catanzaro, Adams. "Coccidioidomycosis. Part II." Am Rev Respir Dis (2010): 727-734. Print. Einstein, Hans. & Catanzaro, Antonino. Coccidioidomycosis. Washington : National Foundation for Infectious Diseases, 2009. Print. Galgiani, John. "Coccidioidomycosis." Clinical Infectious Diseases (2009): 1217-1223. Print. Hagan, William. Bruner, Dorsey. & Timoney, John. Hagan and Bruner's microbiology and infectious diseases of domestic animals. Ithaca : Comstock Pub. Associates, 2010. Print. Ioachim, Harry L & Medeiros, Jeffrey L. Ioachim's lymph node pathology. Philadelphia : Lippincott Williams & Wilkins, 2008. Print. Kauffman, Carol. Essentials of clinical mycology. New York: Springer, 2011. Print. Pappagianis, Demosthenes. "Epidemiology of Coccidioidomycosis." Current Topics in Medical Mycology (2009): 199-238. Print. Stevens, David. "Coccidioidomycosis." The New England Journal of Medicine (2010): 1077-1082. Print. Sellon, Debra. & Long, Maureen. Equine infectious diseases. St. Louis : Saunders Elsevier, cop., 2009. Print. Tabor, Joseph. Epidemiological Study of Coccidioidomycosis in Greater Tucson, Arizona. New York: ProQuest, 2009. Print. Williams, Lippincott. Professional guide to diseases. Philadelphia : Wolters Kluwer Health, 2009. Print. Williams, Lippincott. Lippincott's guide to infectious diseases. Philadelphia : Wolters Kluwer Health, 2011. Print. Read More