Skip to main content

28-02-2011 | Diabetes | Article

Hand washing may reduce false hyperglycemia test results


Free abstract

MedWire News: Researchers recommend that diabetic patients wash their hands with tap water before fingertip blood glucose sampling in order to prevent a false hyperglycemia test result.

The suggestion is based on the findings of a study carried out by Takahisa Hirose (Juntendo University School of Medicine, Tokyo, Japan) and colleagues that demonstrated abnormally high blood glucose test results after fingertip sampling in volunteers who had recently peeled fruit, without subsequently washing their hands.

Interestingly, the researchers found that swabbing the fingertip to be tested with an alcohol swab was not a sufficient alternative to hand washing.

Hirose and co-authors recruited 10 healthy volunteers to test whether preparation of fruit, which is high in fructose and glucose, could lead to false blood glucose readings.

Eight healthy participants were asked to peel an orange, grape, or a kiwi fruit and then undergo blood glucose testing with no hand washing or alcohol swabbing (n=2), after hand washing using tap water (n=2), after use of one alcohol swab (n=2), or after use of five alcohol swabs (n=2). Two volunteers acted as controls and did not peel fruit but swabbed their fingertip with alcohol on the day of testing.

Median blood glucose levels after testing were similar in controls and in those who washed their hands before testing, at 93.5 versus 89.5 mg/dl. However, median levels in the group that peeled fruit with no hand washing or swabbing before testing, and who swabbed once or five times with alcohol prior to testing, were significantly higher at 238.0, 178.5, and 118.5 mg/dl, respectively.

Patients with diabetes are encouraged to self monitor their blood glucose using fingertip capillary testing as it has been found to provide them with strong motivation for improved self care.

But it is important to ensure that the results of these tests are as accurate as possible so that antihyperglycemic medication is not used incorrectly, say Hirose and team.

The authors highlight the fact that none of the instruction booklets for the blood glucose monitors available in Japan suggest hand washing before testing, and say that their results show that this should be changed.

The results of this study are published in the journal Diabetes Care.

MedWire ( is an independent clinical news service provided by Current Medicine Group, a trading division of Springer Healthcare Limited. © Springer Healthcare Ltd; 2011

By Helen Albert