In endemic regions, primary coccidioidal pneumonia may account for ~25% of all community-acquired pneumonia (1). It occurs 1-3 weeks after exposure to arthroconidia. The presence of erythema nodosum or erythema multiforme is considered a favorable prognostic sign and is due to a robust immune response rather than dissemination (2). Radiographic findings are usually consistent with segmental or lobar consolidations and may have hilar or mediastinal adenopathy (3). Before the advent of advanced imaging, mediastinal adenopathy was thought to be a risk factor for disseminated disease; however, more recent evidence has not demonstrated such an association (4). Pleural effusion has been estimated to occur in 5-15% of primary pulmonary coccidioidomycosis (5, 6). In a recent series, pleural effusions were diagnosed more often in those with primary pulmonary infection than those with disseminated disease (p<0.001) (5). Pleural effusions are exudative, often with a lymphocytic predominance, and may have eosinophilia. Empyema occurred in a quarter of pleural effusions, and resolution required thoracotomy in one series (5). However, in a recent series of pediatric cases, McCarty et al. found that of 13 patients with pleural effusion and 4 with empyema, none required decortication, and only two were in need of chest tube drainage (7).

Whether to treat or to observe acute pneumonia is an unresolved matter due to the lack of prospective randomized trials. Indeed, current guidelines depend heavily on expert opinion and clinical experience. It is estimated that ~95% of symptomatic primary coccidioidomycosis may resolve spontaneously (8, 9). While many clinicians may elect to treat diagnosed primary coccidioidomycosis, the use of empiric antifungals for community-acquired pneumonia in endemic regions is unproven, and in fact, very early administration may abrogate the development of IgG antibodies (although the clinical significance of this is unclear) (10). Factors that influence the decision to treat are prolonged infection, radiographic findings, complement fixation titers, immunosuppression, and comorbidities. If antifungal therapy is determined necessary, fluconazole or itraconazole are recommended for 3-6 months and possibly longer depending on the clinical response. Pregnant patients have a significant risk for dissemination and can be treated with amphotericin B (AmB) or immediately postpartum with fluconazole (8). Some experts suggest the use of azoles during the 2nd to 3rd trimester and an AmB-based regimen during the 1st trimester (11).

References

  1. Valdivia L, Nix D, Wright M, et al. Coccidioidomycosis as a common cause of community-acquired pneumonia. Emerging infectious diseases 2006; 12(6): 958-62.
  2. Eldridge ML, Chambers CJ, Sharon VR, Thompson GR, 3rd. Fungal infections of the skin and nail: new treatment options. Expert review of anti-infective therapy 2014; 12(11): 1389-405.
  3. Thompson GR, 3rd. Pulmonary coccidioidomycosis. Seminars in respiratory and critical care medicine 2011; 32(6): 754-63.
  4. Mayer AP, Morris MF, Panse PM, et al. Does the presence of mediastinal adenopathy confer a risk for disseminated infection in immunocompetent persons with pulmonary coccidioidomycosis? Mycoses 2013; 56(2): 145-9.
  5. Merchant M, Romero AO, Libke RD, Joseph J. Pleural effusion in hospitalized patients with Coccidioidomycosis. Respir Med 2008; 102(4): 537-40.
  6. Thompson GR, Sharma S, Bays DJ, et al. Coccidioidomycosis: adenosine deaminase levels, serologic parameters, culture results, and polymerase chain reaction testing in pleural fluid. Chest 2013; 143(3): 776-81.
  7. McCarty JM, Demetral LC, Dabrowski L, Kahal AK, Bowser AM, Hahn JE. Pediatric coccidioidomycosis in central California: a retrospective case series. Clin Infect Dis 2013; 56(11): 1579-85.
  8. Galgiani JN, Ampel NM, Blair JE, et al. Coccidioidomycosis. Clinical infectious diseases: an official publication of the Infectious Diseases Society of America 2005; 41(9): 1217-23.
  9. Thompson GR, 3rd, Stevens DA, Clemons KV, et al. Call for a California coccidioidomycosis consortium to face the top ten challenges posed by a recalcitrant regional disease. Mycopathologia 2015; 179(1-2): 1-9.
  10. Thompson GR, 3rd, Lunetta JM, Johnson SM, et al. Early treatment with fluconazole may abrogate the development of IgG antibodies in coccidioidomycosis. Clin Infect Dis 2011; 53(6): e20-4.
  11. Bercovitch RS, Catanzaro A, Schwartz BS, Pappagianis D, Watts DH, Ampel NM. Coccidioidomycosis during pregnancy: a review and recommendations for management. Clin Infect Dis 2011; 53(4): 363-8.