Determining the degree of accuracy of Combar-10 reagent strip in diagnosing bacterial meningitis

Rajkumar D., Ilangumaran L., Umashankar A.


Background: The gold standard for diagnosis of meningitis depends on cerebrospinal fluid (CSF) examination by microscopy, biochemistry, and culture, which require experienced personnel and laboratory support. We conducted this study to determine if urinary reagent strip is useful to make a semi-quantitative assessment of protein, glucose, and presence of leukocyte esterase in CSF.

Methods: All consecutive CSF samples were evaluated in a blinded fashion. CSF was tested using Combur-10 urinary reagent strip as an index test, and CSF microscopy and biochemistry as reference standards. Combur-10 (Boehringer Mannheim) is an urinary reagent strip used to estimate ten parameters including protein, glucose, and leukocytes. We estimated diagnostic accuracy of each index test using corresponding cut-off levels (glucose <1 + vs. CSF glucose <50 mg/dL; protein 2 + and 3 + vs. CSF protein >30 mg/dL and >100 mg/dL; leukocyte esterase positivity vs. >10 granulocytes in CSF sample). We constructed receiver operating curves (ROC) to evaluate overall performance of index tests and estimated area under the curve (AUC).

Results: CSF samples of 150 patients were included in the study. Of the three tests, diagnostic accuracy of protein estimation (2+ or more on reagent strip) was best for detection of CSF proteins greater than 50 mg/dL [sensitivity 93.2% (95% CI 86.63-96.67); specificity 91.49% (95% CI 80.07, 96.64)], with AUC of 0.97. Leukocyte esterase positivity by test strip had a sensitivity of 90% (95% CI 82.08, 94.65) and specificity of 91.6% (95% CI 81.93, 96.39) for detection of CSF granulocytes of more than 10/mm3.

Conclusions: The degree of accuracy of Combar-10 reagent strip in diagnosing bacterial meningitis is very high similar to CSF microscopy and biochemistry.


Cerebrospinal fluid, Meningitis, Urinary reagent strip

Full Text:



Tunkel AR, Scheld WM. Acute meningitis. In: Mandell GL, Bennett JE, Dolin R. Principles and Practice of Infectious Diseases. 5th ed. Philadelphia: Churchill Livingstone; 2000:959-996.

Ministry of Health, National Health Foundation, Technical Group on Meningitis. 2000. Available at

Feigin RD, Pearlmon E. Bacterial meningitis beyond the neonatal period. In: Feigin RD, Cherry JD. Textbook of Pediatric Infectious Diseases. 4th ed. Philadelphia: WB Saunders; 1998:400-429.

Quagliarello VJ, Scheld WM. Treatment of bacterial meningitis. N Engl J Med. 1997;336(10):708-16.

Tesoro LJ, Selbst SM. Factors affecting outcome in meningococcal infections. Am J Dis Child. 1991;145:218-20.

Beck PD, Rainier-Pope CR. The assessment of the value of a reagent strip in testing cerebrospinal fluid. S Afr Med J. 1966;40:882-4.

Bonev V, Gledhill RF. Use of reagent strips to diagnose bacterial meningitis. Lancet. 1997;349:287-8

Romanelli RM, Thome EE, Duarte FM, Gomes RS, Camargos PA, Freire HB. Diagnosis of meningitis with reagent strips. J Pediatr (Rio J). 2001;77:203-8.

Moosa AA, Quortum HA, Ibrahim MD. Rapid diagnosis of bacterial meningitis with reagent strips. Lancet. 1995;345:1290-1

Salvador OJM, Cortes ZL, Garcia CJJ. Usefulness of reactive strips in the diagnosis of suppurative meningitis, at the patient’s bedside. An Esp Pediatr. 1988;29:105-8.