The answer is D [Pulmonology, Cardiology].
A. In those with unlikely probability, a D-dimer test should
be performed and, if normal, the disease can be safely
B. Although a normal perfusion scan adequately rules out
pulmonary embolus (PE) and a high-probability perfusion-ventilation scan adequately rules in PE, the major disadvantages are the high proportion of nondiag- nostic test results (∼50%) and therefore the need for additional (costly) testing, usually with pulmonary angiography.
C. The classic gold standard is pulmonary angiography, which is an invasive method requiring expertise. Hence, complementary strategies have evolved to diagnose PE more readily.
D. At present, the most popular method to identify PE is the multislice spiral CT of the chest. This technique accu- rately detects PE and, if normal, has been shown to also safely rule out the presence of an embolus. Another advan- tage is the possibility of detecting an alternative disease in the thorax in those in whom PE is excluded, which may provide an explanation for the presenting symptoms.
The answer is B [Pulmonology, Infectious Disease].
A. It is possible that the patient has viral pneumonia; however,
persistent fever and rales indicates a bacterial etiology.
B. Best practice for community-acquired pneumonia is to start either a macrolide or doxycycline, as it is most likely
streptococcus or mycoplasma.
C. If the patient was at extremes of age, had comorbidities, or
other risk factors, then it might be prudent to obtain a CBC. A sputum culture might be necessary for those at high risk (alcoholics, immunocompromised, recently hos- pitalized patients), as it may be caused by uncommon res- piratory pathogens. Sputum cultures are difficult to obtain and often fail to reveal the microbe responsible; therefore, they are not obtained in uncomplicated cases.
D. The patient is not in respiratory distress. Neither oxygen nor hospitalization is required for a healthy, immunocom- petent patient with community-acquired pneumonia. Outpatient antibiotics with follow-up in 24 to 48 hours is the recommended management in this case.