Dipstick spot urine pH does not accurately represent 24 hour urine PH measured by an electrode
Int. braz. j. urol
;
42(3): 546-549, graf
Artigo
em Inglês
| LILACS
| ID: lil-785718
ABSTRACT
ABSTRACT Objectives To determine whether spot urine pH measured by dipstick is an accurate representation of 24 hours urine pH measured by an electrode. Materials and Methods We retrospectively reviewed urine pH results of patients who presented to the urology stone clinic. For each patient we recorded the most recent pH result measured by dipstick from a spot urine sample that preceded the result of a 24-hour urine pH measured by the use of a pH electrode. Patients were excluded if there was a change in medications or dietary recommendations or if the two samples were more than 4 months apart. A difference of more than 0.5 pH was considered an inaccurate result. Results A total 600 patients were retrospectively reviewed for the pH results. The mean difference in pH between spot urine value and the 24 hours collection values was 0.52±0.45 pH. Higher pH was associated with lower accuracy (p<0.001). The accuracy of spot urine samples to predict 24-hour pH values of <5.5 was 68.9%, 68.2% for 5.5 to 6.5 and 35% for >6.5. Samples taken more than 75 days apart had only 49% the accuracy of more recent samples (p<0.002). The overall accuracy is lower than 80% (p<0.001). Influence of diurnal variation was not significant (p=0.588). Conclusions Spot urine pH by dipstick is not an accurate method for evaluation of the patients with urolithiasis. Patients with alkaline urine are more prone to error with reliance on spot urine pH.
Texto completo:
DisponíveL
Índice:
LILACS (Américas)
Assunto principal:
Urina
/
Urinálise
/
Urolitíase
/
Concentração de Íons de Hidrogênio
Tipo de estudo:
Guia de Prática Clínica
/
Estudo observacional
/
Estudo prognóstico
Limite:
Humanos
Idioma:
Inglês
Revista:
Int. braz. j. urol
Assunto da revista:
Urologia
Ano de publicação:
2016
Tipo de documento:
Artigo
País de afiliação:
Estados Unidos
Instituição/País de afiliação:
Cleveland Clinic Foundation/US
Similares
MEDLINE
...
LILACS
LIS