We often see patients with Pyrexia of Unknown Origin (PUO). Ongoing fever without an obvious source of infection is a diagnostic challenge.
Having ruled out the common chest, bowel or urine infections, we have run blood and urine tests to look for tropical diseases (eg Dengue Fever or Malaria depending upon travel history) legionella, borrelia (Lyme disease) viral antibodies and inflammatory markers. We may have found no obvious cause initially but signs of infection ie elevated neutrophil white cell count and ESR/CRP. The next stage is to run blood cultures and carry out imaging including chest, abdomen and pelvis CT scans plus echocardiography.
We have successfully diagnosed in this way subacute bacterial endocarditis (SBE) which can be treated with a prolonged inpatient course of intravenous antibiotics and in one case heart valve replacement was necessary. Our work at samedaydoctor private walk in clinics is often challenging as we endeavour to use all available diagnostic options available to us to make a correct diagnosis and initiate treatment.