CHEM PATH Flashcards
Contraindications to Lumbar puncture (4).
- raised ICP
- coagulopathy/thrombopoenia
- local infection
Normal CSF glucose relative to plasma glucose in an adult patient.
N= 60-80%
decrease glucose CSF:plasma ratio (<0.6) is common seen in what cause of meningitis.
Bacterial meningitis (<0.4 typical)
Tuberculosis meningitis
Fungal meningitis
Hypoxia (anaerobic metabolism of glucose = less ATP/glucose)
how to prevent spurous decrease in a CSF chemistry collection for glucose.
Must be collected in NaF tube
Chloride is usually Decreased in patients with ___ due to very high –ve proteins
TB
The two negative charge ion in the CSF?
Cl- and HCO3-
Give three (3) conditions where lactate is increased.
Cerebral hypoxia – infarctions, seizures
Diffuse meningeal conditions esp bacterial meningitis (hypoxia dt inflammation and cerebral oedema)
Markedly elevated with certain IMDs e.g. PDH; mitochondrial myopathies
Plasma concentration of the protein (directly proportional)
Protein↑ with increased permeability - infection or inflammation
Protein is highly elevated in TB menigitis
yes
GLUT-1 in the brain does not need insulin to transport glucose.
yes,
GLUT-1 also occurs in RBC
The protein in the CSF increases as it goes down.
as it travelled down, water leave. leaving the protein.
NaF tubes- inhibit glycolytic enzymes
to colllect for glucose test also use for plasma
CSF glucose:plasma Ratio ______ in viral meningitis
normal
The IgG Index is used to screen for ______.
intrathecal (local) IgG production
NB!! must know the formula
______________is a good indicator of BBB permeability
Albumin
An increased ratio means increased permeability
Glycine nton nton
Spinal fluid is an ultrafiltrate of plasma that lacks which of the following high molecular weight proteins?
a) Beta lipoprotein
b) Alpha-2 macroglobulin
c) IgM
d) All of the above
D
On electrophoresis, CSF (cerebrospinal fluid) shows a prominent peak corresponding to which protein?
a) Albumin
b) Pre-albumin
c) Beta lipoprotein
d) IgM
Pre-albumin
Which transferrin isoform is unique to CSF?
a) A1-transferrin
b) B1-transferrin
c) B2-transferrin
d) C1-transferrin
C
B2-transferrin is formed in CSF by the enzymatic action of which enzyme?
a) Amylase
b) Protease
c) Neuraminidase
d) Lipase
.
The protein concentration of spinal fluid is approximately what percentage of plasma?
a) Less than 0.1%
b) Around 1%
c) Approximately 5%
d) Greater than 10%
B
The protein concentration of spinal fluid varies with age. Which group tends to have higher protein levels?
a) Adolescents
b) Young adults
c) Elderly individuals
d) Infants
D
