Week 10: 10.2 body fluid highlights Flashcards
Describe a Lumbar Puncture (LP)
Needle in subarachnoid space to collect CSF for:
1) Dx
2) Tx (therapeutic)
What are some urgent indication for lumbar puncture (LP)?
Suspected:
1) CNS infection (meningoencephalitis)
-brain abscess is an exception (space-occupying lesion)
2) SAH
What are 3 potential contraindications for LP (lumbar puncture)?
1) Increased ICP [due to space-occupying lesion]
2) Coagulopathies/anticoagulation/thrombocytopenia
3) Infection overlying LP site
Potential LP complications include what?
1) Headaches due to persistent CSF leak
2) Bleeding [of SQ blood vessel from needle]
3) Infection
What amount of CSF pressure is generally abnormal?
>20
[know this]
LP / CSF Analysis:
1) Should it be opaque or clear? What would the opposite indicate?
2) What color should it be?
3) When may CSF also appear grossly bloody (red tinge)?
1) Clear; turbidity can occur w. high WBCs/ RBCs
2) Colorless
3) if significantly increased RBCs
CSF analysis:
1) What is Xanthochromia?
2) What causes it?
3) When may it be seen?
1) Yellow or pink discoloration
2) Breakdown of hemoglobin
3) Subarachnoid hemorrhage (SAH)
-Can also be seen if significantly increased CSF protein or serum bilirubin
CSF analysis: When should Xanthochromia NOT be present?
Acute bleeding from traumatic tap
Normal CSF is _________________, but may have a small number of certain __________ when sampled by LP
acellular (no cells); cells
CSF RBCs:
1) Normal?
1) 0-5 RBCs
2) Blood in CSF
3) Subarachnoid hemorrhage or traumatic puncture
CSF WBCs:
1) Number of WBCs?
2) Number of PMNs?
3) When can WBC elevations (pleocytosis) occur?
1) 0-5 WBCs/microL
2) 0-3
3) Infections, noninfectious inflammatory states, traumatic tap
Acute infectious meningitis: _______________________ usually predominate in bacterial; __________________ usually predominate in viral
Neutrophils (PMNs); lymphocytes
LP / CSF Analysis: Pathogen Testing
List 3 different types
1) Gram stain
2) Culture & Sensitivity (C&S): CSF culture
3) Molecular tests for viruses, bacteria, and fungi
CSF protein:
1) Does normal CSF have a lot of protein?
2) Albumin-to-globulin ratio normally _____________ in CSF than blood .
3) Increased CSF total protein can occur with many CNS diseases, like what?
1) Very little normal total protein
2) higher
3) Infectious and noninfectious conditions and those associated with obstruction of CSF flow; can also be elevated due to bleeding
CSF Protein- Immunoglobulins:
1) Should there be many IGs in CSF?
2) IGs are typically assessed when evaluating for CNS inflammatory disorders, in which what?
1) Very few
2) CSF immunoglobulins may be increased
Describe CNS Immunoglobulins (part of CNS protein)
-Normally very few in CSF, elevated in CNS inflammatory disorders
-Can ID with:
1) Increased IgG index
2) Spikes/bands on CSF protein electrophoresis + immunofixation
> Oligoclonal bands: common in neuroinflammatory disorders like MS
>Monoclonal band (monoclonal gammopathy) suggests B cell/plasma cell disorder (e.g., malignancy)
Oligoclonal bands are common in ____________ disorders like MS, and ____________ bands suggest malignancy
neuroinflammatory; monoclonal
Describe CSF glucose (when is it low, normal, or high?)
1)Low (hypoglycorrhachia) in bacterial/fungal CNS infections (+ certain noninfectious)
2) Normal (typically) during viral CNS infections
3) High if hyperglycemia
CSF Lactate (lactic acid):
1) Elevated CSF levels may occur in __________________ cerebral injury, SAH, infectious meningitis.
2) When is it often elevated? When is it normal?
1) hypoxic-ischemic
2) Often elevated in acute bacterial meningitis (prior to abx) but normal in viral meningitis (good diagnostic accuracy in differentiating)
LP/ CSF analysis: Cytology and Tumor markers may help identify what?
Malignancy/metastasis
For acute bacterial meningitis, ID what the following will be:
1) WBCs
2) Protein
3) Glucose
4) Others
starred; don’t need to know numbers
1) Very high (neutrophilic/ PMN predominance)
2) Very high
3) Low
4) Positive gram stain/ bacterial culture; CSF lactate high
For acute viral meningitis, ID what the following will be:
1) WBCs
2) Protein
3) Glucose
4) Others
starred; don’t need to know numbers
1) Modestly high; lymphocytic prominence
2) High [modestly]
3) Normal
4) CSF lactate is normal
For fungal meningitis, ID what the following will be:
1) WBCs
2) Protein
3) Glucose
4) Others
starred; don’t need to know numbers
Variable findings: WBC count, protein, and glucose may be similar to either bacterial or viral
For SAH, ID what the following will be:
1) RBCs
2) Xanthochromia
3) Others
starred; don’t need to know numbers
1) RBCs very high
2) Xanthochromic color
3) high opening pressure
