Which condition shows the least use of blood count?

Infectious mononucleosis generally shows the least use of blood count in the context of diagnosing and monitoring the condition compared to the other options given. While a complete blood count (CBC) can provide some useful information about infectious mononucleosis, such as elevated white blood cells and atypical lymphocytes, the diagnostic confirmation often relies more on specific serological tests—such as the heterophile antibody test (Monospot test)—rather than on blood counts alone.

In contrast, anemia is primarily diagnosed and monitored through blood counts, which reveal levels of hemoglobin, hematocrit, and red blood cell indices. Similarly, leukemia is heavily reliant on CBC results to identify abnormalities in white blood cell counts, which can indicate the presence of malignant cells. Thrombocytopenia, characterized by low platelet counts, also requires regular monitoring through blood tests to assess the severity and guide treatment.

Thus, because infectious mononucleosis can often be diagnosed accurately with specific tests without the necessity of detailed blood counts, it shows the least reliance on blood count results among the listed conditions.