Chapter 13 Cerebrospinal Fluid Flashcards
Clear, colorless liquid formed in the 4 ventricles of the brain by secretion from the choroid plexus and a smaller contribution from the ependymal cells that line the brain and spinal cord
Cerebrospinal fluid (CSF)
What does CSF do
- Supplies nutments to nervous tissue
- removes metabolic waste
- Produces a mechanical barrier to protect and cushion the brain and spinal cord
Central nervous system consists of
Brain and spinal cord
What 3 membranes line the central nervous system and what layer are they?
- Dura mater (outer layer)
- Arachnoid mater (middle layer)
- Pia mater (inner layer)
CSF flows between which layers
Arachnoid mater and pia mater
How is CSF produced?
By choroid plexus cells and ependymal lining cells (blood-brain barrier)
Where does CSF circulate
Through the ventricular system: cerebrum, brain stem, completely covers surface of brain and spinal cord
Name the 6 structures
From superior to inferior: Skull Dura mater Subdural space Arachnoid Subarachnoid space Pia mater
Total volume of CSF in adults and neonates
Adults: 85-150ml
Neonates: 10-60ml
Pathologic alterations of CSF are caused in
Infections (meningitis), cerebral hemorrhage, tumors, leukemia, syphilis, demyelinating diseases (multiple sclerosis), and other blood-brain barrier conditions
Blockage of drainage of CSF can be caused by
Tumor, inflammation, developmental malformation, meningitis, hemorrhage or injury
Continued production of CSF causing an increase in pressure
Hydrocephalus
How many tubes are used for collection of CSF and where are they sent?
3 tubes (additional sometimes submitted):
- tube 1 for chemistry and immunology (can be frozen)
- tube 2 for microbiology (keep at room temp)
- tube 3 for hematology and cytology (can be refrigerated)
If there is only a small volume of CSF what testing is priority?
Micro and cellular
What do you do if you receive a sample that is not labeled
Run the test and then contact nurse. Sample can go bad and diagnosis could be contagious
If blood distribution in CSF sample is even
Hemorrhage
If blood in CSF sample is uneven
Traumatic tap
Cause, and significance if sample is crystal clear
Cause: normal
Significance: normal
Cause, and significance if sample is hazy, turbid, cloudy, milky, viscous
Cause: WBCs, Microorganisms, protein
Significance: meningitis, brain-blood barrier disorders, IgG production within CNS, mucin adenocarcinomas
Cause, and significance of bloody sample
Cause: RBCs
Significance: hemorrhage, traumatic tap
Cause, and significance of xanthochromic sample
Cause: hemoglobin, bilirubin, carotene, melanin
Significance: Old hemorrhage, RBC degradation, bilirubin
Cause, and significance of clotted sample
Cause: protein, fibrinogen
Significance: brain-blood barrier disorders, traumatic tap
Cause, and significance of pellicle sample
Cause: protein, clotting factors
Significance: tubercular meningitis
Normal amount of WBCs and RBCs
WBC: 0-5 per microliter (specifically lymphocytes and monocytes)
RBC: not present
Cell counts are performed with
Hemacytometer
Normal ratio of lymphocytes to monocytes in adults and children
Adults: 70:30
Children: 30:70
Increased amount of normal cells
Pleocytosis
Pleocytosis of normal cells is valuable in determining the cause of what
Meningitis
Increased amounts of neutrophils =
Bacterial
Increased amount of lymphocytes =
Viral, tubercular, fungal, parasitic, syphilis
Major clinical significance if reactive lymphocytes are found
Viral, tubercular, and fungal meningitis
Multiple sclerosis
Major clinical significance in neutrophils with granules less prominent than blood are found
Bacterial meningitis
Major clinical significance if neutrophils with lens that disintegrate rapidly are found
Early cases of viral, tubercular, and fungal meningitis
Cerebral hemorrhage
Major clinical significance if monocytes by themselves are found
Viral, tubercular, and fungal meningitis
Multiple sclerosis
Clinical significance if macrophages that may contain phagocytized RBCs appearing as empty vacuoles or ghost cells, hemosiderin granules, and hematoidin crystals are found
RBCs in spinal fluid from hemorrhage
Contrast media
Clinical significance if lymphoblasts, myeloblasts, or monoblasts are found
Acute leukemia
Clinical significance if lymphoma cells with cleft nuclei are found
Disseminated lymphomas
Clinical significance if traditional or classic plasma cells are found
Multiple sclerosis
Clinical significance if eosinophils are found
Parasites
Allergic
Clinical significance if ependymal, choroidal, and spindle-shaped cells with distinct nuclei and cell walls are found
Diagnostic procedures
Clinical significance if malignant cells seen in clusters with fusing of cell borders and nuclei are found
Metatastic carcinomas
Primary central nervous system carcinoma
Neutrophils
What is present?
- Primarily in bacterial meningitis
- often contain phagocytized bacteria
- increased early viral, fungal, tubercular, parasitic
- vacuoles may be present
Neutrophils
Monocytes (bean-shaped) and lymphocytes (one big nucleus)
What is present?
- viral, fungal, tubercular
- Reactive ________ with viral
- multiple sclerosis has 50 or fewer ______ per microliter, both normal and reactive
- seen in HIV and AIDS
Lymphocytes and monocytes
Blanks = lymphocytes
Eosinophils
What is present?
- parasitic and fungal infections (primarily Coccidioides immitis)
- medications and shunts into the central nervous system
Eosinophils
Pink to orange fluid supernatant - breakdown of Hb
Xanthrochromia
18 hours for histiocytes to mobilize and phagocytose RBCs
Erythrophagocytosis
Product of Hb metabolism
Intracellular or extracellular
Hematoidin crystals
Examples of true CSF hemorrhage
Xanthrochromia, erythrophagocytosis, Hematoidin crystals
Erythrophagocytosis
Hematoidin crystals
Reason for a traumatic tap
Clipped blood vessel and doctor error
How to determine if it was a traumatic tap
- total RBC count significantly higher in 1st tube than last
- WBC and RBC counts reflect same ratio as PB
- 1 to 2 WBCs for every 1000 RBCs
Bacterial meningitis shows an increase in
Neutrophils
Viral, tubercular or fungal meningitis shows an increase in
Lymphocytes
Viral, tubercular or fungal shows an increase in
Monocytes
Parasitic, allergic, drug reaction shows an increase in
Eosinophils
What is found if a spinal tap needle penetrates vertebral bone and draws back bone marrow or an infant or adult has osteoarthritis
Hematopoietic precursors
Arachnoid, ependymal and choroid plexus cells can be mistaken for
Malignant cells
Choroid plexus cells in CSF
- no borders/open borders between cells
Arachnoid cell
Reactive lymphocytes
- mononucleosis/some hepatitis
- larger than normal lymphocytes, larger cytoplasm
Artifactual change in neutrophils
What is the most common yeast organism and what stain is used
Cryptococcus and you use India ink
What Microbio exam do you use for bacteria and fungi
Gram stain
What Microbio exam do you use for Cryptococcus neoformans
India ink
What Microbio exam do you use for tuberculosis meningitis
Acid-fast stain
What Microbio exam do you use for ameba Naegleria fowleri
Wright stain
What Microbio exam do you use to detect bacterial cause
Culture
Which species?
Candida albicans
Which species?
Cryptococcus neoformans
Describe malignant cells
- similar to what 3 fluids
- ______ cells: less ____; looks like ___ ____
- No _____ cells in CSF: presence of large _____ cells
- Plural, pericardial, peritoneal
- carcinoma: cohesive; hematopoietic malignancies
- mesothelial: tissue
Maliquant cell must be differentiated from what 3 cells
Choroid plexus cells, ependymal cells, arachnoid cells
What CNS diagnoses involve hematopoietic malignancies
- Leukemia: ALL, ANLL
- high grade lymphomas: lymphoblastic, immunoblastic, Burkitt lymphomas
Adenocarcinoma (cancer cells)
Small cell carcinoma
Acute lymphocytic leukemia
Normal amount of protein
15-45 mg/dL
Damage to the brain-blood barrier such as meningitis and hemorrhage, elevated immunoglobulins such as multiple sclerosis, and degenerate neurological tissues are indications of
Increased protein
How to defect oligoclonal bands
Protein electrophoresis
Monitors multiple sclerosis
Myelin Basic Protein
Used to assess permeability of blood-brain barrier
CSF/Serum albumin index
Normal and abnormal ranges of CSF/Serum albumin index
Normal: less than 9
Minimal impairment: 9 to 14
Moderate to severe: 15 to 100
Complete breakdown of barrier: exceeding 100
What four bands predominate CSF in protein electrophoresis
Transthyretin, albumin, two transferrin (one known as “tau protein”)
Identifies oligocional bands that are present CSF but absent in serum in multiple sclerosis
Protein electrophoresis
Used as a marker for identifying a CSF leakage from the nose, ear, eyes or head/neck wound after injury
Tau protein (asialo-tranferrin)
Oligoclonal bands are seen in
Multiple sclerosis, neurological disorders including Guillain Barre, encephalitis, neurosyphilis, and in neoplastic disorders
Normal value of glucose in plasma
60-70%
Glucose test results seen in bacterial meningitis
Decreased glucose and increased WBCs and neutrophils
What cause a decreased glucose result
Alterations of active transport of glucose across blood-brain barrier
Lactate results and effect in bacterial, fungal or tuberculous infections
Lactate increased and oxygen decrease of flow to brain tissue
Lactate results in viral meningitis
Decreased
Abnormal glutamine results and symptoms/cause
Increased glutamine when ammonia level increases
Associated with loss of consciousness or coma and liver disorders
Immunologic test for neurosyphilis
VDRL
Immunologic test for bacterial and fungal organizations
Assays
