4.4 M) I) Meningitis

Front 1

Which of the following is incorrect regarding CSF analysis?
1. > 20% of cases with bacterial infection will have an initial lymphocyte.
predominance
2. Viral meningitis may initially be dominated by neutrophils on CSF.
3. Culture is the Gold standard for determining the causative organism in meningitis.
4. PCR gives a faster result than culture- and can be more sensitive.
5.Latex agglutination can have a role in partially treated meningitis.

Back 1

1. > 10%

Front 2

In regards to CSF opening pressure-which is incorrect?
1. The patient must be lateral decubitus positioning.
2. hyperventilation lowers the opening pressure.
3. Straining increases the opening pressure.
4. Normal opening pressure is < 25cm in obese patients.
5. Elevated opening pressure > 25cm is seen only in meningitis.

Back 2

5. Elevated opening pressure > 25cm = intracranial hypertension

Seen in :
1. meningitis
2. intracranial haemorrhage
3. tumours
4. Idiopathic intracranial hypertension

Front 3

In regards to Supernatant colour in CSF analysis, which is incorrect?
1. turbidity occurs after WCC > 200 WCC or RCC > 400.
2. Xanthochromia = yellow/orange /pink colour.
3. Hb breaks down to oxyhaemoglobin + methaemoglobin + bilirubin
4. xanthochromia is seen after 6 hours, and lasts 2-4 weeks
5. Within 12 hours of SAH - > 90% patients will have xanthochromia.

Back 3

4. Xanthochromia is seen after 2 hours, and lasts 2-4 weeks.

Front 4

What situational states can xanthochromia be seen in CSF?

Back 4

1. SAH
2. infectious conditions
3. Inflammatory conditions
4. Traumatic tap.{> 100,000 RBC}
5. Newborns

Front 5

In regards to CSF cell counts, which is incorrect?
1. Normal CSF WBC <= 5
2. 99% patients with bacterial meningitis will have > 100 WCC {per mm cubed}
3. 60% patients with bacterial meningitis will have WCC > 1000.
4. Elevated WCC can occur with seizures.
5. Elevated WCC can occur with intracranial malignancy AND haemorrhage.

Back 5

3. 87%

Front 6

Which is incorrect regarding The CSF cell Differential?
1. The WCC in normal adult CSF = 80% lymphocytes + 20% monocytes.
2. A solitary eosinophil or PMN in the CSF can be normal
3. The cell differential alone cannot differentiate between bacterial and non bacterial meningitis.
4. Lymphocytosis can be seen in the CSF in Viral or Fungal or Tuberculous CNS infections.
5. The CSF in Bacterial meningitis is TYPICALLY dominated by polymorphonucleocytes {PMN}

Back 6

1. 70% lymphocytes + 30% monocytes

Front 7

In regards to eosinophils in the CSF, which is incorrect?
1. Their presence can be normal
2. eosinophilic meningitis = > 10 eosinopils
3. Eosinophilic meningitis usually due to fungal infections
4. Eosinophilia of CSF can be due to viral or fungal or rickettsial or parasitic infection.
5. Adverse drug reactions and malignancy can also cause eosinophilic meningitis.

Back 7

3. Parasitic

Front 8

Which is incorrect regarding Microscopic examination of CSF in meningitis?
1. Gram stain is + 60-80% cases of meningitis.
2. Gram stain is + in 25% partially treated cases of meningitis.
3. Up to 10% of initial gram stains are misread by Laboratory Personnel.
4. Only 35% of INITIAL CSF smears will be positive for Acid fast Bacilli in Tuberculosis.
5. AFB staining can have an increased yield of 87% positivity by performing 4 smears.

Back 8

2. 40-60% cases of partially treated meningitis will have + gram stain

Front 9

Which is incorrect in linking the CSF stain and the organism?
1. Indian Ink = Cryptococcus
2. Giemsa Stain = Toxoplasmosis
3. Simple wet preparation = Protozoan
4. Wright Stain = Toxoplasmosis
5. Wright Stain = Helminth infection

Back 9

5. Helminth infection = simple wet preparation

Front 10

Causes of raised CSF Protein {7}

Back 10

1. Infection
2. Intracranial haemorrhage
3. Malignancy
4. Guillain Barre Syndrome
5. Multiple Sclerosis {MS}
6. Endocrine abdnormalities
7. Traumatic tap

Front 11

Causes of increased opening pressure on LP {5}

Back 11

1. Meningitis
2. Cerebral tumour
3. brain abscess
4. Intracranial haemorrhage
5. Benign intracranial hypertension

Front 12

Causes of reduced opening pressure on LP {5}

Back 12

1. Hyperventilation
2. CSF Leak
3. Dehydration
4. Diabetic coma
5. Chronic CNS degenerative disease

Front 13

Bacterial antigen studies on CSF{5}

Back 13

1. Neisseria [ 50-90% sensitivity]
2. S pneumoniae [ 50-100%]
3. H influenzae [ 80%]
4. Cryptococcus [ 90%]
5. GB Strep.

Front 14

CSF PCR testing - Infections tested for?

Back 14

1. Herpes
sens 95%
spec 100%
2. TB
sens 80%
spec 95%

Front 15

Which is incorrect regarding Bacterial Antigen studies in CSF?
1. It is via ELISA technique
2. sensitivity for Neisseria = 50-90%
3. S pneumoniae sensitivity can be as high as 100%
4. Sensitivity is improved when CSF + blood + urine are tested simultaneously.
5. It can test for Cryptococcus.

Back 15

1. It is via Latex Agglutination technique.

Front 16

List for Elevated Protein in CSF? {10}

Back 16

1. Alcoholism
2. Abscess
3. Diabetes
4. Disc herniation
5. Haemorrhage
6. Tumour
7. epilepsy
8. MS
9. Uraemia
10. Trauma

Front 17

3 causes of marked elevation in CSF protein?

Back 17

1. Meningitis
2. Tumour
- brain
- spinal cord
3. Polyneuritis

Front 18

In regards to CSF Glucose, which is incorrect?
1. CSF glucose is proportional to blood glucose { CSF 60-80% of venous sample}
2. Decreased CSF glucose usually indicates bacterial meningitis {diffuse meningeal inflammation}
3. Glucose can be low in Herpes simplex meningitis.
4. An increase in CSF glucose is of no diagnostic value.
5. Glucose is always normal in viral meningitis

Back 18

5. Mumps and herpes simplex meningitis can have low CSF glucose.

Front 19

Which is incorrect regarding CSF glucose?
1. low CSF glucose = hypoglycorrhachia
2. 10% patients with bacterial meningitis can have normal CSF glucose
3. CSF glucose levels do not normally get higher than 17mmol/L.
4. low CSF glucose can be seen in chemical meningitis
5. SAH can give low CSF glucose.

Back 19

2. 50%

Front 20

Which organisms can be tested for via PCR on CSF samples?

Back 20

1. HSV
2. TB
3. EBV
4. Enterovirus***
5. CMV
6. Acute Neurosyphilis

Front 21

Which is incorrect regarding PCR on CSF?
1. PCR is expensive
2. PCR has been a great advance in the diagnosis of meningitis
3. PCR has high sensitivity and specificity
4. PCR is actually less sensitive than culture for Enterovirus meningitis.
5. PCR can be performed with small volumes of CSF.

Back 21

4. PCR is more sensitive and faster than culture for Dx of enterovirus meningitis.