Utility of urine reagent strips in cerebrospinal fluid analysis: An aid to bedside diagnosis of meningitis

Context: The provision of initial treatment to a patient with suspected meningitis depends greatly on early recognition and rapid diagnostic evaluation of cerebrospinal fluid (CSF) leukocytes, proteins, and glucose. The diagnosis is time critical and timely intervention has an implication on the prognosis and outcome. Reasonably, sound laboratorial setups are not available in our country in the primary health-care level and, even in the settings where they are available, long waiting periods precede the availability of results. Aims: We conducted this study to emphasize the role of urine reagent strip test as a rapid diagnostic tool in CSF analysis. Settings and Design: This is a prospective single-blinded study on 100 consecutive CSF samples received with in 1h of tap. Subjects and Methods: All the 100 samples were subjected to definitive test being CSF microscopy and biochemical analysis of proteins and sugar and index test being a semi quantitative analysis of CSF leukocytes, proteins, and sugar by urinary reagent strips. Statistical Analysis Used: The diagnostic accuracy of the reagent strip for different cutoff levels was estimated and tabulated in the form of sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio. Results: 77% of cases were in the pediatric age group and 23% cases were adults. The sensitivity and specificity for leukocytes by the strip method for ≥15 cells/cumm were 89.28% and 98.61%, respectively, which increased to 100% with an increase in the counts. The reagent strip test had a sensitivity of 85.71% and a specificity of 95.65% for the protein levels >30 mg/dl which increased to 100% with an increase in protein levels. The reagent strip test for glucose was highly specific (100%) but less sensitive. Conclusions: The results indicate that urine reagent strip is instrumental in bedside CSF analysis and has a future stand in the diagnosis of meningitis.