Haematology in Systemic Disease Quiz

See CDC guidance on parasitic disease and eosinophilia. Option E identifies eosinophilia, an increased eosinophil count, as a clue to tissue-invasive helminths. Helminths are parasitic worms, and their larvae can pass through tissues during infection. Eosinophils release substances that contribute to defence against these larger parasites. The association is particularly useful during tissue migration, but a normal count does not exclude infection. Eosinophilia is also seen with allergy and some drug reactions, so it is a clue rather than a diagnosis. This is more precise than the rule that every parasitic infection produces eosinophilia.

Neutrophilia (D) commonly accompanies bacterial infection or stress, rather than specifically suggesting invasive worms. C is lymphocytosis, an increased lymphocyte count that may accompany viral illness. Widespread platelet consumption (A) suggests a process such as DIC; it is not the characteristic white-cell response to migrating helminths. B describes deficient red-cell production, whereas parasitic anaemia can arise through several other mechanisms, including blood loss or haemolysis, depending on the organism.