Lumber Puncture

Question 1

List 4 reasons that indicate lumbar puncture

Answer 1

primary or metastatic neoplasm, cerebral hemorrhage, meningitis, encephilitis

Question 2

from what space is CSF obtained

Answer 2

subarachnoid

Question 3

What is normal P for CSF

Answer 3

70-200 mm H2O

Question 4

What is a normal WBC count in CSF

Answer 4

0-5 cells/mcL adult (0-20 for kiddos)

Question 5

Which WBC type makes up 40-80% of CSF

Answer 5

lymphocytes

Question 6

What is the normal protein value in CSF

Answer 6

15-45 mg/dL

Question 7

What is the normal glucose value in CSF

Answer 7

50-75 mg/dL (60-70% of serum glucose. serum levels must be taken before LP)

Question 8

What is the normal Cl value in CSF (not normally tested)

Answer 8

700-750 mg/dL

Question 9

serology is performed on CSF to screen for what condition

Answer 9

neurosyphils

Question 10

what 2 conditions present with increased (>40 units/L) CSF lactate dehydrogenase (LDH)

Answer 10

inflammation or bacterial meningitis (produced by neutrophil)

Question 11

4 ways bacterial meningitis (MCC strep pneumoniae) would present in CSF values

Answer 11

200-20,000 PMNs, glucose50 mg/dL

Question 12

4 ways aseptic meningitis would present in CSF values

Answer 12

25-2,000 LYMPHOCYTES, glucose normal to low, proteins>50 mg/dL, slightly increased P

Question 13

4 ways granulomatous meningitis would present in CSF values

Answer 13

100-1,000 LYMPHOCYTES, glucose < 45, slightly increased P, Protein >50 mg/dL

Question 14

why is opening pressure increased for lumbar puncture (4)

Answer 14

tumors, infection, hydrocephalous, intercranial bleeding

Question 15

why is opening pressure decreased for lumbar puncture (3)

Answer 15

hypovolemia (shock or dehydration), chronic leakage of CSF (previous puncture site), nasal sinus fracture

Question 16

2 ways to differentiate between a traumatic tap and a subarachnoid bleed

Answer 16

traumatic tap will show clotting (if no blood thinners) and the redness should decrease in the fluid when it starts flowing

Question 17

what is yellow tinged CSF called? what can it indicate (3)?

Answer 17

xanthochromia= hyperbilirubinemia, hypercarotenemia (normal in kiddos), melanoma

Question 18

cerebral absess and bacterial meningitis both present with these WBCs in CSF

Answer 18

PMNs

Question 19

In what conditions are mononuclearleukocytes elevated in CSF (3)

Answer 19

viral infection, tubercular infection, encephalitis

Question 20

4 examples of noninfectious menigeal irritation

Answer 20

carcinomatosis, sarcoidosis, SLE, chemical menigitis

Question 21

3 ways noninfectious meningitis would present in CSF values

Answer 21

increased WBC count, increased protein, low or normal glucose

Question 22

what form of meningitis is most common in young adults and teens

Answer 22

Neisseria menigitidis

Question 23

4 most common causes viral (aseptic) meningitis

Answer 23

Herpes simplex, Coxsackievirus, Echovirus, Infectious mononucleosis

Question 24

4 most common causes of encephalitis

Answer 24

Herpes simplex, arbovirus, rabies virus, flavivirus (West Nile and Japanese)

Question 25

Conditions tested in CSF protein electrophoresis

Answer 25

multiple sclerosis, neurosyphilis, immunogenic degenerative processes

Question 26

Conditions where lactic acid of CSF is increased

Answer 26

anaerobic metabolism (low blood flow or decreased oxygenation), bacterial infections, fungal infections, low CSF glucose

Question 27

Tumor markers used in CSF

Answer 27

CEA, Alpha-fetoprotein, hCG