NUR 502 Module 6 Disease Process Case Study on Valley Fever Example

Dust, Fever and Fatigue: A Disease Process Case Study of Primary Pulmonary Coccidioidomycosis in a Phoenix Road Worker

Student Name

Edson College of Nursing and Health Innovation, Arizona State University

NUR 502: Advanced Health Assessment and Health Promotion

Instructor Name

Month Day, Year

Dust, Fever and Fatigue: A Disease Process Case Study of Primary Pulmonary Coccidioidomycosis in a Phoenix Road Worker

Case Presentation

Mr. R., a 47-year-old road construction worker in Phoenix, came to a community health center with three weeks of dry cough, fever, pleuritic chest pain, night sweats and fatigue so severe he missed work. His symptoms began about two weeks after a windy week of grading a new road. He had been prescribed an antibiotic for presumed bacterial pneumonia at an urgent care clinic, without improvement. He has no chronic illnesses, takes no medications and does not smoke. He has no health insurance through his employer and pays for care on a sliding fee scale. On examination, his temperature was 38.2 C, heart rate 96 and oxygen saturation 95% on room air. He had scattered crackles over the right lower lung and painful red nodules on both shins. Chest radiography showed a right lower lobe infiltrate with enlarged hilar lymph nodes. Coccidioidal serology was positive.

Normal Physiology

Air entering the lungs carries particles, microbes and spores. Normal defenses include the mucociliary escalator in the larger airways, which traps and clears particles, and alveolar macrophages, which engulf organisms that reach the alveoli. When macrophages encounter organisms they cannot easily destroy, they release signals that recruit other immune cells. Cell-mediated immunity, coordinated by T lymphocytes, is the key defense against fungal pathogens: T cells activate macrophages and form granulomas, organized collections of immune cells that wall off organisms the body cannot immediately kill.

Pathophysiology

Coccidioidomycosis is caused by Coccidioides, a fungus that lives in desert soils of the southwestern United States, particularly parts of Arizona and California (Kimes et al., 2020). When soil is disturbed by construction, farming or wind, the fungus's tiny arthroconidia become airborne and are inhaled. In the lung, each arthroconidium transforms into a spherule, a structure that enlarges and fills with endospores, then ruptures and releases them, each capable of forming a new spherule. This cycle provokes an inflammatory response, producing pneumonia, and is controlled mainly by cell-mediated immunity. Many infections cause few or no symptoms. In others, the illness resembles community-acquired pneumonia, with cough, fever, chest pain and profound fatigue. Immune reactions can cause erythema nodosum, the painful shin nodules Mr. R. has, which reflect a strong cellular response and are associated with a lower risk of dissemination. People with impaired cellular immunity, such as those with HIV, organ transplants or immunosuppressive therapy, are at higher risk of severe or disseminated disease affecting skin, bones or the meninges (Kimes et al., 2020).

Physical Assessment and Diagnosis

Assessment focuses on the lungs, skin, joints and signs of dissemination. Findings include crackles or decreased breath sounds over the affected lobe, fever, erythema nodosum or erythema multiforme, joint aches sometimes called desert rheumatism, and fatigue. The nurse should ask about residence and travel in endemic areas, occupation and dust exposure, because the national guideline stresses that residence in or recent travel to endemic regions is critical for recognizing the infection (Galgiani et al., 2016). Signs of dissemination, such as new skin lesions, bone pain, headache or neck stiffness, require urgent evaluation. Diagnosis rests on serologic tests for coccidioidal antibodies, sometimes supported by culture or imaging. A key lesson in Mr. R.'s case is that valley fever is often mistaken for bacterial pneumonia, leading to repeated antibiotic courses that do not help.

Pharmacology

Many primary pulmonary infections resolve without antifungal therapy, and the guideline describes initial pulmonary infection as eventually resolving whether or not antifungal therapy is given, while recommending that patients be followed over time (Galgiani et al., 2016). Antifungal treatment is often considered for patients with debilitating symptoms, extensive disease or risk factors for complications. The most commonly used agent is fluconazole, an azole antifungal that inhibits fungal ergosterol synthesis, weakening the fungal cell membrane. Nurses should know that azoles inhibit CYP450 enzymes and interact with many drugs, that fluconazole is generally avoided in pregnancy, and that therapy may continue for months. Mr. R.'s severe fatigue and inability to work led his clinician to start fluconazole with follow-up visits every few weeks.

Health Promotion and Prevention

There is no vaccine for valley fever, so prevention focuses on reducing exposure and recognizing illness early. For outdoor workers, measures include wetting soil before digging, using equipment with enclosed cabs, and wearing respiratory protection during dusty work, along with employer training. An outbreak investigation among 3,572 workers building two solar farms in California found 44 cases, nine hospitalizations and a median of 22 missed workdays, and only 6 of 25 patients who often did soil-disturbing work reported frequent use of respiratory protection (Wilken et al., 2015). Health promotion also includes teaching workers and clinicians to suspect valley fever when pneumonia does not respond to antibiotics, which can shorten the time to diagnosis and avoid unnecessary antibiotics. For Mr. R., the nurse taught him about expected recovery, which can take weeks to months, signs of worsening that require prompt care, medication adherence and the importance of follow-up blood tests. Because he is uninsured and cannot afford to lose work, the nurse also connected him with the center's medication assistance program and wrote a note supporting modified duties.

Vulnerability and Equity

Outdoor workers in Arizona's construction and agriculture industries are disproportionately exposed, often lack paid sick leave and may work for employers who do not provide respiratory protection. These factors make a common infection more harmful for people already facing economic risk. Nurses can advocate for workplace dust control and for clinician education, and can make sure valley fever is considered early for patients with relevant exposure.

References

Galgiani, J. N., Ampel, N. M., Blair, J. E., Catanzaro, A., Geertsma, F., Hoover, S. E., Johnson, R. H., Kusne, S., Lisse, J., MacDonald, J. D., Meyerson, S. L., Raksin, P. B., Siever, J., Stevens, D. A., Sunenshine, R., & Theodore, N. (2016). 2016 Infectious Diseases Society of America (IDSA) clinical practice guideline for the treatment of coccidioidomycosis. Clinical Infectious Diseases, 63(6), e112-e146. https://doi.org/10.1093/cid/ciw360

Kimes, K. E., Kasule, S. N., & Blair, J. E. (2020). Pulmonary coccidioidomycosis. Seminars in Respiratory and Critical Care Medicine, 41(1), 42-52. https://doi.org/10.1055/s-0039-3400998

Wilken, J. A., Sondermeyer, G., Shusterman, D., McNary, J., Vugia, D. J., McDowell, A., Borenstein, P., Gilliss, D., Ancock, B., Prudhomme, J., Gold, D., Windham, G. C., Lee, L., & Materna, B. L. (2015). Coccidioidomycosis among workers constructing solar power farms, California, USA, 2011-2014. Emerging Infectious Diseases, 21(11), 1997-2005. https://doi.org/10.3201/eid2111.150129