Case 48

Published on 18/02/2015 by admin

Filed under Allergy and Immunology

Last modified 18/02/2015

Print this page

This article have been viewed 1457 times

CASE 48

RG is 45 years old and has recently returned from a trip to China. While there he visited several small local markets, as well as a number of other typical tourist sites, including the Great Wall near Beijing. Two weeks after his return he developed a fever, which seemed only to defervesce intermittently with acetaminophen. During the past 2 days he has complained to his family of feeling more short of breath than usual and has had a crushing headache. Finally, tonight his overall condition worsens and he comes to the emergency department.

This is a worrisome presentation (particularly in view of recent evidence for infection by a number of transmissible emerging viruses, including severe acute respiratory syndrome [SARS], swine flu, avian flu, West Nile virus, and so on). He should be quarantined during workup! What should you do as part of the workup? What are the treatment options?

QUESTIONS FOR GROUP DISCUSSION

1. Although this patient certainly falls within a high risk for SARS, more common disorders are still more common. How would you ensure that this is not a typical viral infection and/or community-acquired pneumonia?

2. Given that his fever of the past 2 days only abates intermittently with acetaminophen how will you treat the fever?

3. This patient is feeling more short of breath than usual. What information would you hope to gain from a chest radiograph? What tests would you perform to determine how poorly the lungs are functioning? If sufficient supplemental oxygen is not possible by mask, how would you proceed?

4. Along with the fever and difficulty breathing, RG has a crushing headache. Explain why you would request computed tomography (CT) of his head and a lumbar puncture.

5. Having ruled out common infections, what emerging infectious agents should be high on the list of possibilities, particularly given his travel history? What tests would you request?

6. Essentially all the tests that you have requested come back without dramatic results (including the CT and lumbar puncture with cultures). The white blood cell count is minimally elevated (12,000/mm³, but still only 55% neutrophils and 40% lymphocytes (normal is ∼60% neutrophils). What does this indicate regarding the type of pathogen with which RG is infected?

7. The chest radiograph shows hazy infiltrates throughout. This is consistent with the white blood cell differential (see question 6). Most importantly, your patient can only maintain an oxygen saturation greater than 92% on 60% oxygen given by re-breather mask. Therefore, it is necessary to continue oxygen therapy and to monitor this patient’s chest carefully. Explain how you would do this. Note that at this point you are still treating symptoms, not disease.

8. Serology comes back positive for West Nile virus and not for any of the other viruses of concern. What are the sequelae of West Nile viral infection? A vaccine is not available.

9. SARS is a coronavirus that has caused significant morbidity and mortality worldwide. Recent data suggest evidence for overexpression of the novel procoagulant fibroleukin in the lungs of SARS patients (a phenomenon seen also in the case of other single stranded RNA viruses, such as fulminant hepatitis C infection). What is fibroleukin? What is its normal role?

10. Discuss possible therapeutic avenues of approach regarding question 9.

RECOMMENDED APPROACH

Implication/Analysis of Family History

We are not provided with any family history; and given the urgency of the clinical presentation, the immediate goal is to treat the symptoms.

Implication/Analysis of Clinical History

RG is short of breath and has had intermittent fever for the past 2 days and a crushing headache. All of these symptoms are typical of viral infections. Despite his travel history, which must be kept in mind, we should consider first those infections that are common. Thus, you need to ensure this is not a typical infection (e.g., community-acquired pneumonia) and/or viral infection. However, he should be quarantined during workup. RG has a fever, which is only resolved intermittently; therefore, to get his temperature under control use simple measures (e.g., acetaminophen or nonsteroidal anti-inflammatory drugs) as well as sponging his body with warm water.

Common Infections

Buy Membership for Allergy and Immunology Category to continue reading. Learn more here

Related

Problem-Based Immunology