Correct!
2. CBC, UA, lumbar Puncture, CXR, inflammatory markers, metabolic panel
The patient has presented with a constellation of symptoms. The basic investigations would be one which would try to rule in/out broader categories of the pathological processes which might be going on.
The CBC can be revealing with regards to anemia and possible infectious processes. Lumbar puncture is important to r/o meningitis given pt.’s initial presentation symptoms. UA and metabolic panel can help in identifying infectious process plus identifying any chemical abnormality which would give a clue to underlying pathological process which might be going on. The patient was hypoxic and it would be worthwhile to get a CXR as a scanning modality to identify a possible pulmonary disease process. Venous blood gases (VBG) will not be able to assess the oxygen status and CT chest will not be an appropriate initial investigation. ECHO can be a reasonable investigation since the patient was complaining of lower extremity swelling, however, it did not necessarily need to be done on initial presentation as overt signs of heart failure were not appreciated during physical examination. Inflammatory markers can help us in assessing if the process is acute or chronic. CT of the head is not warranted in this patient as he does not have papilledema on physical examination. Bronchoscopy is not an appropriate initial investigation.
Our patient had a lumbar puncture which was unremarkable for an infectious process. His creatinine was grossly elevated along with pro-BNP, CRP and ESR. Troponins were negative and UA showed microscopic hematuria. Potassium was slightly elevated at 5.2. A chest x-ray (CXR) was performed (Figure 1).
Figure 1. Portable CXR done in the Emergency Department shows the patient to have basilar predominant confluent hazy opacities.
What is the probable differential based on CXR, history and presenting labs? (Click on the correct answer to proceed to the 3rd of 6 panels)