1. B IOCHEMISTRY P RACTICAL By: Dr. Beenish Zaki

2. CSF A NALYSIS

3. C EREBROSPINAL FLUID The surface of the central nervous system is covered by the meninges: Duramater Arachnoid Piamater. The space between arachnoid and piamater is called sub-arachnoid space. CSF is secreted by the choroid plexuses. In normal healthy adults rate of CSF formation is 100-250ml/24hrs.

4. CSF FORMATION AND CIRCULATION

5. SITE OF WITHDRAWL CSF is withdrawn by a procedure called lumbar puncture. Spinal cord ends near the first lumbar vertebra. CSF is obtained by passing Lumbar Puncture (L.P) needle between L4-L5. Second preferred site is L3-L4 into the sub- arachnoid space.

6. SITE OF LUMBAR PUNCTURE

7. NORMAL COMPOSITION: Colour : Clear colorless; no coagulum or deposit PH : 7.3 Pressure:60-150 mm of Hg Specific gravity: 1.006-1.002 Cells : 0-4 mononuclear cells/mm 3 Protein content: 10-45mg/dl Globulins: absent Glucose: 45-100mg/dl Chlorides: 120-130meq/l

8. M EASURING OPENING PRESSURE

9. ABNORMALITIES In appearance Blood stained a)Due to traumatic tap RBC under microscope have normal shape b) In pathological conditions like sub-arachnoid haemorrhage in this blood is homogeneously mixed with CSF under microscope RBC have a crenated appearence.

10. ABNORMALITIES C ONT ’ In appearance Xanthochromia:-Yellow colorization of CSF due to either: bilirubin Carotenoids Turbidity :- is due to presence polymorphs/mm 3 Coagulum:- In tuberculosis meningitis cob-web like coagulum is seen if the fluid is allowed to stand overnight from the web tubercle bacilli can be examined easily under microscope.

11. ABNORMALITIES C ONT ’ In Glucose CSF glucose is increased in :- Diabetes Encephalitis Cerebral abscess CSF glucose is decreased in :- Meningitis due to bacteria. The glucose reduces from the fluid because the organisms are glycolytic and thus use up the glucose.

12. A CASE A 19 year old student presents with fever, headache, nausea, vomiting. On examination there is neck stiffness.

13. INDICATION FOR CSF COLLECTION CSF infection Hemorrhage Malignancy Demyelinating Diseases

14. CSF PROTEINS ESTIMATION

15. M ETHOD AND P RINCIPLE Method: Turbidity Method Principle: Proteins are precipitated with Trichloro acetic acid which gives a turbidity.

16. P ROCEDURE ProcedureBlank(ml)Test(ml) Sample-1.00 Reagent TCA 4.003.00 Mix well and take reading immediately using green filter

17. O BSERVATION AND C ALCULATION O.D of Test= O.D of Standard=0.16 Concentration of sample = O.D Test X concentration of standard (mg/dl) O.D Standard O.D Test x 100 0.16 O.D-Optical Density

18. R EFERENCE RANGE A ND C LINICAL C ONDITIONS Adult: 10-45 mg/dl CSF Protein Increased in: Meningitis Meningoma Acoustic Neuroma Multiple Sclerosis CSF Protein Decreased in: Malnutrition

19. CSF C HLORIDE ESTIMATION

20. M ETHOD AND P RINCIPLE Method: Titration Method Principle: Chlorides present in CSF reacts with Silver nitrate to form silver chloride this reacts with the indicator to form a colored complex

21. P ROCEDURE Pipette 1ml of CSF and 2ml of distilled water into a conical flask. Add 3 drops of potassium chromate as the indicator. Titrate against silver nitrate in the burette to a faint brick red color which is the end point.

22. O BSERVATION AND C ALCULATION Initial Reading= Final Reading= Concentration of sample: mEq. Chloride per liter of CSF= ml of silver nitrate solution required x 30 mEq/L= Milliequivalent/L

23. R EFERENCE RANGE A ND C LINICAL C ONDITIONS Adult: 90-120 mEq/L CSF Chloride Increased in: Hypertension Renal disease CSF Chloride Decreased in: Meningitis

25. T HANK YOU !