Which result on an automated differential suggests that a peripheral smear should be manually reviewed?

A result showing 15% monocytes on an automated differential indicates a significant increase in monocytic cells, which may warrant further investigation. In normal circumstances, monocyte counts typically range between 2% and 10% of total white blood cells. The elevated percentage could suggest a number of underlying conditions, including infections, inflammatory processes, or hematological disorders such as monocytic leukemia or chronic inflammation.

Thus, if a lab report shows a disproportionately high number of monocytes, it is prudent for a technician or physician to manually review the peripheral smear. This allows for verification of the automated counts, evaluation of the morphology of the monocytes, and assessment for any other atypical cells that may not be accurately reflected in the automated differential. Manual review helps ensure the right clinical decisions are made based on accurate and comprehensive data.

In this context, although the other values listed might also raise questions if they were significantly abnormal, the 15% monocyte result stands out as most likely to deviate from expected values and suggests a potential clinical significance requiring further analysis.