Modifier 25 should be appended to the office or other. outpatient service code to indicate that a significant, separately. identifiable E/M service was provided by the same physician. on the same day as the preventive medicine service.
The level of homocysteine in the blood can be measured with a simple blood test that is often, but not always, done after fasting. Homocysteine levels of 12 mmol/L are considered normal and levels below 10 mmol/L are considered desirable.
Many studies have investigated the health effects of high homocysteine levels and/or having two C677T MTHFR gene mutations. Some studies suggest that an elevated level of homocysteine in the blood is associated with an increased risk for heart disease, including coronary heart disease and stroke.