... blood test is most often used to diagnose lactic acidosis and find out how severe it is. It can also help evaluate and ... any of the many conditions that can cause lactic acidosis. If you have been diagnosed with high levels of lactate, you may need to have repeated tests to monitor your condition. If you have symptoms of meningitis, you may need to have your lactate levels measured in your blood and your cerebrospinal fluid. Symptoms of meningitis include: Severe headache Fever Stiff neck Sensitivity to light What ...