A Study of Bedside Diagnosis of Bacterial Meningitis Using Urinary Strip Reagent for Semiquantitative Analysis of Cerebrospinal Fluid.

Abstract

Background: Meningitis is an inflammatory disease of the leptomeninges and is defined by the abnormal number of white blood cells (WBCs) in the cerebrospinal fluid (CSF). Meningitis-related mortality and morbidity can be decreased with early diagnosis and antibiotic administration. The most reliable method of diagnosis is still CSF analysis. Yet, a straightforward bedside test would be helpful for early identification due to the absence of experienced staff, laboratory, and transport services at the primary health care level in developing countries.

Materials and methods: Patients fitting the inclusion criteria were admitted to Gandhi Hospital, and a lumbar puncture was performed under aseptic conditions. Using the SEIMENS Multistix 10 SG reagent strip as the index test and CSF microscopy and biochemistry as the gold standard diagnostic test, CSF was examined for proteins, sugars, and leukocytes.

Results: Among 100 CSF specimens evaluated, 52 (52%) were normal and 48 (48%) were considered as having pleocytosis. The overall performance of the urine leukocyte strip when compared to CSF leukocytes had a sensitivity of 95.8%, specificity of 67.3%, negative predictive value (NPV) of 94.6%, and positive predictive value (PPV) of 73.1%. The protein portion of the urine strip was compared to quantitative CSF proteins and showed a sensitivity of 90%, specificity of 70%, PPV of 66.7%, NPV of 91.3%, and diagnostic accuracy of 78%. The glucose portion of the reagent strip also performed better than the standard test, with a sensitivity of 100%, specificity of 93.8%, PPV of 90%, NPV of 100%, and diagnostic accuracy of 96%. For the diagnosis of bacterial meningitis, the strip glucose showed a sensitivity of 100%, specificity of 69.7%, PPV of 35%, NPV of 100%, and diagnostic accuracy of 74%. The significance of the reagent strip test for leukocytes, proteins, and sugars, when compared to the standard test, was established at a 95% confidence interval (CI) using the Pearson Chi-squared test.

Conclusion: The urinary reagent strip is a simple test for a semiquantitative assessment of CSF, which may help with the diagnosis of meningitis at the point of care. It can also assist in deciding whether to begin antimicrobial therapy in settings with limited resources.