Valley Fever
Overview
Fungal infection caused by Coccidioides immitis or C. posadasii that occurs primarily as a respiratory tract infection, although generalized dissemination may occur
Also known as Valley fever or San Joaquin Valley fever
Pathophysiology
After spores are inhaled, cell activation and cytokine formation stimulate inflammatory cells and facilitate killing of the organism, initially infecting the lungs.
In the lungs, the spores change from barrel-shaped spores to spheres and enlarge, eventually changing into individual endospores that are released into the tissues and initiate an inflammatory response.
Normal immune response helps control the infection, although immunosuppression may delay resolution of the infection.
Infection can extend into the lung parenchyma and then spread via lymphatic system, draining into the bloodstream and to distant sites.
The incubation period is 1 to 4 weeks after exposure, with an average of 10 to 16 days; disseminated illness may take weeks to months to occur.
Causes
Inhalation of spores from cultures of infected persons
Inhaled spores of C. immitis or C. posadasii found in the soil
Risk Factors
People who work in fields, on ranches, or in areas where they are exposed to dust from soil
Incidence
Disseminated illness is more common in dark-skinned males, pregnant females, and immunosuppressed individuals.
Coccidioidomycosis is endemic to the southwestern United States, especially between the San Joaquin Valley in California, Arizona (highest number of cases), and southwestern Texas; it's also found in Mexico, Guatemala, Honduras, Venezuela, Colombia, Argentina, and Paraguay.
This disease primarily affects Filipino Americans, Hispanic Americans, Native Americans, and blacks because of population distribution and an occupational link (common in migrant farm laborers).
The disease affects all age groups.
The incidence is highest during the late summer and early fall when the crops have already been harvested, leaving the soil dry.
Complications
Synovitis
Hepatosplenomegaly
Pulmonary scarring
Arthritis
Septic shock
Assessment
History
Possibly asymptomatic (up to 65% of patients)
Living or traveling to an endemic area
Dry cough
Pleuritic chest pain
Rash
Sore throat
Malaise
Joint pain
Night sweats
Weight loss
Physical Findings
Itchy maculopapular rash
Local swelling and redness in involved sites (with musculoskeletal involvement)
Decreased breath sounds; dullness on percussion; increased tactile and vocal fremitus
Hepatomegaly and splenomegaly with disseminated disease
Diagnostic Test Results
Laboratory
Complement fixation detects immunoglobulin G antibodies.
Positive serum precipitins (immunoglobulins) may be seen.
C. immitis spores may be detected through immunodiffusion testing of sputum, pus from lesions, and tissue biopsy.
Presence of antibodies in pleural and joint fluid and a rising serum or body fluid antibody titer (indicate dissemination) may be present.
White blood cell count may be increased.
Eosinophil count may be increased.
Erythrocyte sedimentation rate test may be increased.
Imaging
Chest radiography shows bilateral diffuse infiltrates, nodules, mediastinal or hilar adenopathy, or pleural effusion.
Computed tomography scanning (thorax) reveals abnormalities, such as multiple nodules, interlobar septal thickening, and consolidation.
Other
Biopsy of the affected tissue (lung or skin lesion) reveals evidence of a fungus.
Treatment
General
Symptomatic measures
Humidification of environment
Venous thromboembolism (VTE) prophylaxis if hospitalized
Diet
As tolerated
Activity
Activity as tolerated
Medications
IV fluids
Amphotericin B cholesteryl sulfate complex for severe and rapidly progressive disease
Ketoconazole (oral), fluconazole, or itraconazole for nondisseminated disease
Analgesics, such as nonsteroidal anti-inflammatory drugs (NSAIDs) for pleuritic chest pain
Antitussives for cough
Surgery
Reserved for chronic pulmonary coccidioidal infection with complications
Excision or drainage of lesions
Lobectomy for severe pulmonary lesions
Nursing Considerations
Nursing Interventions
Employ standard precautions.
Encourage rest periods as needed.
Apply antiembolism stockings or sequential compression stockings to prevent VTE.
Cluster activities to minimize energy expenditure and oxygen demand.
Encourage the use of energy-conservation measures.
Administer oxygen as ordered based on oxygen saturation levels via pulse oximetry.
Auscultate lung sounds for changes.
Encourage coughing and diaphragmatic breathing exercises, and incentive spirometry to promote lung expansion.
Elevate the head of the bed or encourage the patient to sit up to allow for maximum chest expansion and to ease the work of breathing.
Encourage respiratory hygiene measures.
Maintain a patent airway.
Provide cool mist humidification and other respiratory care measures to relieve cough.
Administer prescribed medications, such as NSAIDs for pain, antitussives for cough, and antifungal agents.
If ketoconazole is ordered, avoid administration of histamine-2 blockers, which decrease the absorption of ketoconazole.
Encourage adequate fluid intake. Offer frequent sips of fluids. Check skin turgor and inspect mucous membranes for moisture.
Obtain specimens for laboratory testing, such as sputum for cultures and blood for complete blood count.
Reposition at least every two hours, and perform skin assessments. Provide skin care measures as indicated.
Monitoring
Fluid balance status
Intake and output
Vital signs
Pain level and effectiveness of interventions
Sputum color, consistency, and amount
Oxygen saturation level
Cardiopulmonary status
Breath sounds
Level of orientation
Associated Nursing Procedures
Alignment and pressure-reducing device application
Antiembolism stocking application, knee-length
Antiembolism stocking application, thigh-length
Coughing and diaphragmatic breathing exercises
IV secondary line drug infusion
Safe medication administration practices, general
Sequential compression therapy
Sputum collection by expectoration
General
Include the patient's family or caregiver in your teaching, when appropriate. Be sure to cover:
disorder, diagnostic testing, underlying cause, and treatment, including medication therapy
prescribed medications, such as antifungal agents, including drugs, dosages, schedule of administration, expected results, and duration of therapy, possibly ranging from 3 to 6 months
possible adverse reactions associated with medication therapy, and signs and symptoms that need to be reported to a practitioner
that most cases are self-limiting and resolve in a few months but that relapse of extrapulmonary or disseminated disease is possible
proper hand hygiene technique and prevention measures to reduce the risk for exposure, especially for patients involved in working with soil (digging, construction)
appropriate skin care measures
that fatigue and lethargy may continue for weeks or months after other symptoms have resolved
importance of continued follow-up care, initially every 2 to 4 weeks and then every 3 to 6 months for up to 2 years to ensure eradication of the infection.
Participate in a multidisciplinary team to coordinate discharge planning efforts. The team may include the bedside nurse, a respiratory therapist, physical therapist, social worker, care manager, infection preventionist, and pulmonologist.
Determine the appropriate post-hospital setting to which the patient should be discharged.
Assess patient and family understanding of the diagnosis, treatment, prognosis, follow-up, and warning signs for which to seek medical attention.
Assess the patient's level of independence prior to admission.
Evaluate how the current illness will impact the patient's independence.
Identify the patient's formal and informal supports.
Identify the patient's and family's goals, preferences, comprehension, and concerns about discharge.
Confirm arrangements for transportation to initial follow-ups.
Assess/confirm the patient's and family's understanding of prescribed medication, including dosage, administration, expected results, duration, and possible adverse effects.
Assess/confirm the patient's ability to obtain medications; identify the party responsible for obtaining medications.
Ensure that the patient and caregivers have been given the proper medical contact information.
Provide information on smoking cessation, if appropriate.
Provide contact information regarding local support groups or services.
Document the discharge planning evaluation in the patient's clinical record, including who was present/involved in discharge planning and teaching.
Document the patient's understanding of the teaching provided and if follow-up teaching is needed.
