In which condition would you most likely find a Kernig's sign present?

Kernig's sign is a clinical indication that is typically associated with meningeal irritation. It is assessed by flexing the patient's hip and knee at 90 degrees, and then attempting to straighten the knee. If this action causes pain or resistance in the lower back or neck, it is considered a positive Kernig's sign. This finding is particularly relevant in cases of meningitis, as the inflammation of the protective membranes covering the brain and spinal cord can lead to the characteristic symptoms associated with this reflex.

In conditions like stroke, heart attack, or pneumonia, you would not expect to find Kernig's sign. Stroke can present with neurological deficits but does not generally provoke the meningeal signs that Kernig's is indicative of. Heart attack symptoms relate to cardiovascular distress. Pneumonia, primarily a respiratory infection, does not involve the meningeal irritation that would result in a positive Kernig's sign. Thus, the presence of this sign specifically points to meningitis as the most likely condition.