The combur-10 (Roche Diagnostics)urinary reagent strip was used as index test to detect CSF leucocytes by leucocyte esterase estimation, glucose by glucose oxidase-peroxidase method, protein levels by pyrogallol red method and erythrocytes by peroxidase method. The technicians, who performed the index test, were blinded to the results of definitive tests. Undiluted CSF was mixed with the micropipette and 2–3 drops of CSF was then added to patches of leucocytes, proteins, sugar and erythrocytes and reaction was noted after 60–120 s. Then, reaction colors of the test area were compared with the color chart on the label as shown in Fig. 1 . Reference standard for all the parameters as shown on the label of strip are shown in Table 1 .Fig. 1 ![]()
Table 1
Showing color chart scale as shown on the label of combur-10urinary reagent strip.
Reference standard for all the parameters as shown in strip label of combur-10urinary reagent strip.
| Parameter | Normal value in CSF | Principle of strip test | No color | 1+ | 2+ | 3+ | 4+ |
|---|---|---|---|---|---|---|---|
| CSF Leucocyte (cells/mm3) | <5 | Leucocyte esterase estimation | <10 | 10–75 | 75–499 | >500 | – |
| CSF Protein (mg/dl) | 15–45 | Protein error of pH indicator | <29 | 30–99 | 100–499 | >500 | – |
| CSF Glucose (mg/dl) | 40–70 | glucose oxidase-peroxidase method | <50 | 50–99 | 100–299 | 300–999 | 1000 |
| CSF Eythrocyte (cells/cumm) | Absent | Peroxidase method | <5 | 5–10 | 25 | 50 | 250 |