Infectious Disease & Sepsis Labs

Score community-acquired pneumonia severity from five bedside criteria, and see what the score deliberately leaves out.

Convert HBV DNA between IU/mL and copies/mL using an assay-specific factor, and see the log value guidelines are written against.

Turn HBsAg, anti-HBs and anti-HBc results into a plain-English pattern — one of the most confusing readings in laboratory medicine.

Calculate percentage parasitaemia from a thin film count, and see why every level — not just a high one — is abnormal.

Aggregate seven routine observations into the standard ward early-warning score, and the single-parameter rule that overrides the total.

Read a procalcitonin result against the bacterial-infection thresholds used in antibiotic stewardship, and see where it misleads.

Flag suspected infection at higher risk of death or prolonged critical care using three bedside observations and no laboratory tests.

Divide heart rate by systolic blood pressure to catch compensated shock earlier than either number does alone.

Screen for the systemic inflammatory response — four bedside-and-lab criteria that once defined sepsis and are now a screening prompt, not a diagnosis.

Score organ dysfunction across six systems — the score whose 2-point rise, with suspected infection, is the Sepsis-3 definition of sepsis.

Apply the correct induration threshold for the patient’s risk group, from 5 mm in the highest-risk groups to 15 mm with no risk factors.

Turn two viral load results into a log₁₀ change, and see how much of that change is real rather than assay noise.

Convert an absolute viral load in copies/mL or IU/mL to its base-10 logarithm, and see what a log change actually means for treatment response.