Cristian León

Validation of the salivary urea test as a method to diagnose chronic kidney disease.

BACKGROUND Serum urea correlates very well to salivary urea, which can be used as a low-cost, easily accessible and noninvasive diagnostic method for screening patients in early stages of kidney disease, especially in developing countries where resources are limited, giving the possibility of establishing secondary prevention programs later. METHODS One hundred and one people were enrolled: 11 with creatinine clearance (CrCl) less than 10 ml/min per 1.73 m(2); 10 with CrCl of 11-20 ml/min per 1.73 m(2); 12 with CrCl of 21-50 ml/min per 1.73 m(2); 26 with CrCl of 51-80 ml/min per 1.73 m(2) and 42 with CrCl of 81-170 ml/min per 1.73 m(2), to analyze salivary urea test accuracy through construction of a receiver operating characteristic curve. RESULTS Salivary urea cutoff point of 20 mg/dL and a CrCl of 80 ml/min per 1.73 m(2) showed sensitivity (S) of 0.98, specificity (SP) of 0.29, pretest probability (PPT) of 0.58, positive predictive value (PPV) of 0.66, negative predictive value (NPV) of 0.92, posttest positive probability (PTPP) of 0.66 and posttest negative probability (PTNP) of 0.09. A cutoff point of 40 mg/dL and a CrCl of 80 ml/min per 1.73 m(2) showed S=0.80, SP=0.71, PPT=0.58, PPV=0.80, NPV=0.71, PTPP=0.79 and PTNP=0.28. A cutoff point of 100 mg/dL and a CrCl of 80 ml/min per 1.73 m(2) showed S=0.22, SP=1, PPT=0.58, PPV=1, NPV=0.48, PTPP=1 and PTNP=0.52. Receiver operating characteristic curve analysis showed that the best cutoff point for salivary urea was 40 mg/dL. CONCLUSION The salivary urea test has a great capacity to discriminate patients with chronic kidney disease from healthy people, and it was shown that the best cutoff point is 40 mg/dL.

Sodium chloride 0.9% versus Lactated Ringer in the management of severely dehydrated patients with choleriform diarrhoea

INTRODUCTION Although experience within Peru suggests clinical and physiological benefits of treating dehydration caused by diarrhoea with Lactated Ringers solution (LR) over sodium chloride 0.9%, (NaCl) there is little documented scientific evidence supporting this view. It is important to clarify this issue and determine the best solution for use during epidemics. METHODOLOGY Forty patients suffering from dehydration due to choleriform diarrhoea were enrolled in the study. Twenty patients were treated using NaCl (Group A) and the other twenty with LR (Group B). After diuresis recovery was achieved, the patients were continued on a course of oral rehydration salts. Serum electrolytes, arterial pH, HCO3-, and pCO2 were measured at three stages: at admission, after diuresis recovery, and after 12 hours. RESULTS Acidosis was corrected more quickly with LR that NaCl. The hyperosmolality and hypernatremic states were corrected with both solutions. CONCLUSION LR use resulted in a better clinical response than NaCl, illustrated by more rapid physiological correction, showing that mixed metabolic acidosis was corrected more quickly and more appropriately with this treatment.