A man from Mexico brought in by EMS following an MVC....
You are working one evening when EMS brings in a 30-something year old man with a history of Type 2 diabetes who was the driver in an MVC . He reportedly ran off the road and into a tree. He was found outside of the vehicle. He is intoxicated and complaining about his obvious facial trauma. As part of your initial trauma workup, you get the following chest X-ray:
You get more history. Apparently, the patient is an immigrant from Mexico. His only other past medical history is type 2 diabetes.
Interpret the Chest X-ray. What other history do you want to know? What is your differential diagnosis and subsequent diagnostic workup in this trauma patient?
Scroll down for the Case Conclusion
Final diagnosis: Chronic Coccidioidomycosis
Case Conclusion: A cavitary lesion is noted in the left upper lobe. Given his intoxication and mechanism of injury, the patient has a full trauma scan, which demonstrates bilateral nasal bone fractures, an isolated L1 transverse process fracture, and large cavitary lesions in the left upper lobe:
He is put on Tb precautions and admitted. Induced sputum x 3 is negative for AFB. He undergoes bronchoscopy and biopsy which demonstrates infection with Coccidioidomycosis.
Learning Points:
Although the primary intention of imaging in trauma patients is to identify injuries, unanticipated information is often discovered in the course of such testing. Indeed, ~ 30 % of trauma patients undergoing CT will have an incidental finding of some kind, although the clinical significance of these findings is often questionable [1]. Whether or not clinically significant, the emergency medical provider often needs to respond to these findings in some way. In most cases, this involves informing the patient and recommending follow-up. In this patient, the incidental finding of a large cavitary lesion requires a more active response.
Cavities are a manifestation of a wide variety of processes affecting the lung [2]. This includes non-infectious (e.g. malignancy and Wegener’s Granulomatosis) and infectious etiologies. Many different types of infections can lead to cavitary lesions [see Table]. Patients who are chronically immunosuppressed or have pre-existing lung disease are at much higher risk of developing these infections. While most of these are not transmissible from person to person, with the important exception of Tuberculosis. In addition, it is not uncommon for some fungal infections (Aspergillosis, paracoccidiomycosis) to co-exist with Tuberculosis infection. Therefore, patients with new cavitary lesions on imaging should be placed on respiratory isolation pending evaluation for active Tb infection (as this patient was).
Coccidioidomycosis is one of the common endemic mycoses in North America. The endemic mycoses are an often overlooked cause of pulmonary disease. Acquired through environmental exposure, they have have different geographic distributions and extra pulmonary manifestations [3]:
Coccidioidomycosis is also known as valley fever and is the result of inhaling spores in endemic areas such as southern Arizona, central and southern California, southern New Mexico, west Texas and northern Mexico. Most (one half to two thirds) of infections are subclinical [4]. The most common clinical presentation is a self-limited acute or subacute community acquired pneumonia evident 1-3 weeks after initial infection. The minority of infections (5-10%) result in chronic infection or residual pulmonary sequelae, including the development of pulmonary nodules or cavitary lesions. Patients with diabetes (such as this case) are at high risk of developing pulmonary cavities. Disseminated disease is rare, but patients of African American or Filipino descent are at higher risk. However, 30-50% of patients who are chronically immunosuppressed, are at risk for disseminated and occasionally life-threatening disease.
Because most cases of coccidioidomycosis will resolve without anti fungal therapy (including up to 50% with cavitary lesions), decision to initiate anti-fungal therapy in the absence of progressive, disseminated infection is made on a case-by-case basis.
Sometimes even the most dramatic incidental findings are still incidental.
Case Conclusion by Maia Dorsett (@maiadorsett)
- Barrett, T. W., Schierling, M., Zhou, C., Colfax, J. D., Russ, S., Conatser, P., ... & Wrenn, K. (2009). Prevalence of incidental findings in trauma patients detected by computed tomography imaging. The American journal of emergency medicine, 27(4), 428-435.
- Gadkowski, L. B., & Stout, J. E. (2008). Cavitary pulmonary disease. Clinical microbiology reviews, 21(2), 305-333.
- Wheat, L. J. (2009). Approach to the diagnosis of the endemic mycoses. Clinics in chest medicine, 30(2), 379-389.
- Galgiani, J. N., Ampel, N. M., Blair, J. E., Catanzaro, A., Johnson, R. H., Stevens, D. A., & Williams, P. L. (2005). Coccidioidomycosis. Clinical Infectious Diseases, 41(9), 1217-1223.