I read with interest the article by McLean et al, regarding the investigation of sepsis with biomarkers. However, I was interested to see the description of the urinary dipstick "showing the presence of leucocyte and nitrate".
The use of the term "nitrate positive" is widespread but incorrect. Many Gram negative bacteria convert nitrate to nitrite within urine and it is the nitrite that is detected by the reagents on the urine dipstick forming a red azo-dye giving the characteristic colour.
Yours sincerely
Andrew Chetwood
ST6 Urology
Competing interests:
No competing interests
06 February 2015
Andrew Chetwood
ST6 Urology
Basingstoke and North Hampshire Hospitals NHS Trust
Rapid Response:
Dear Sirs,
I read with interest the article by McLean et al, regarding the investigation of sepsis with biomarkers. However, I was interested to see the description of the urinary dipstick "showing the presence of leucocyte and nitrate".
The use of the term "nitrate positive" is widespread but incorrect. Many Gram negative bacteria convert nitrate to nitrite within urine and it is the nitrite that is detected by the reagents on the urine dipstick forming a red azo-dye giving the characteristic colour.
Yours sincerely
Andrew Chetwood
ST6 Urology
Competing interests: No competing interests