Cerebral Spinal Fluid (CSF) Analysis (2023)

FAQs

How much CSF needed for analysis? ›

When this fluid volume is reduced, there is less fluid available to cushion the brain inside the skull. This loss of CSF causes headache and other neurological signs and symptoms and may result in a range of complications. With upright posture, the loss of CSF volume has a greater effect on the brain.

In general, your CSF analysis results may show that you have an infection, an autoimmune disorder, such as multiple sclerosis (MS), or another disease or injury of the brain or spinal cord. Your provider will likely order more tests to confirm your diagnosis.

A total of 8 to 15 mL of CSF is typically removed during routine LP.

If CSF is flowing: collect into 2-3 numbered sterile tubes. 5-10 drops in each is usually adequate, but more may be required depending on investigations ordered. 20 drops = 1 mL.

What are the symptoms of low pressure headaches? The classic symptom is a headache that becomes severe when the patient is upright and quickly disappears when the patient is lying flat. So, the headaches are typically absent first thing in the morning, and start or worsen shortly after getting out of bed.

Intracranial Hypotension Symptoms

Nausea, with or without vomiting. Neck pain or stiffness. Hearing changes, such as muffled hearing or ringing in the ears. Difficulty concentrating.

Intracranial hypotension (ICH) is defined as a CSF pressure less than 60 mm H2O and generally causes a postural headache in patients with the condition.

CSF is produced at a rate of around 500 ml/day; there are estimates that there is approximately 125 mL to 150 mL of CSF in the body at any given time. Depending on the rate of production and absorption (which varies individually), the supply of CSF can be replaced about every 7.5 hours.

Why is CSF important in diagnosis? ›

Analysis of the CSF provides invaluable diagnostic information because diseases take place either within its bounding membranes (e.g., meningitis) or in the adjoining parameningeal structures of the brain (e.g., brain abscess).

Myelography. This test is considered the gold standard for diagnosing and locating CSF leaks. It uses digital subtraction fluoroscopy, a CT or MRI scan, and a contrast dye to locate CSF leaks. It provides the most precise location of a CSF leak and helps to determine the most appropriate treatment plan.

The CSF is clear and colorless in all patients with MS, and most patients have normal cell counts and total protein levels. Even during an acute exacerbation, total CSF protein and cell counts remain normal, although sometimes a modest mononuclear pleocytosis can be identified.

However, you cannot 100 percent confirm or rule out MS based on a spinal tap, explains Dr. Giesser. “Even if the spinal tap is negative, about 10 percent of people who have MS have normal spinal fluid. And if it's positive, other things [other than MS] can cause a positive result,” she says.

An abnormal protein level in the CSF suggests a problem in the central nervous system. Increased protein level may be a sign of a tumor, bleeding, nerve inflammation, or injury. A blockage in the flow of spinal fluid can cause the rapid buildup of protein in the lower spinal area.

An increase of white blood cells indicates infection, inflammation, or bleeding into the cerebrospinal fluid. Some causes include: Abscess. Encephalitis. Hemorrhage.

A spinal tap is done in the lower lumbar area, below the point where the spinal cord ends. So, the risk of harming the spinal cord is avoided. A spinal tap is not surgery.

CSF taken by lumbar puncture (CSF LP)

Four samples of CSF should be collected into clearly labelled sterile containers, which indicate the sequence order of sampling. Sample 2 (0.5 mL minimum) should be in a fluoride/oxalate tube for glucose. Samples 1, 3 and 4 (each 1.5 mL minimum) should be in plain sterile tubes.

A common excuse for an unsuccessful LP in a large patient is that the standard (3.5-in) needle is too short. Although a number of articles discuss the technique of performing LPs,^1,2 we could find no previous studies that actually measured the distance from the skin to the thecal sac.

What happens if you drain too much CSF from a lumbar drain? ›

Excessive CSF drainage or persistent leakage through the dural puncture site can lead to cerebral hypotension and creation of an intracranial subdural hematoma.

Low CSF pressure without a leak being found, called "spontaneous intracranial hypotension", is rare, with a yearly incidence of about 5/100,000. These may be dectected from dural enhancement or lumbar puncture.

A headache that is worse when you sit up and improves when you lie down. It may be associated with light sensitivity, nausea, and neck stiffness. Drainage of CSF from the ear (rarely).

Although CSF leaks may not be readily apparent on imaging, a suspected CSF leak is important to consider because it is fixable, said Dr. Carroll, Assistant Professor of Anesthesiology and Perioperative and Pain Medicine at Stanford University Medical Center in California and a member of the Stanford CSF leak program.

Clinical suspicion for intracranial hypertension should be raised if a patient presents with the following signs and symptoms: headaches, vomiting, and altered mental status varying from drowsiness to coma.

When the fluid leaks out, the volume and pressure of fluid in your skull drops, leading your brain to slump. "This 'brain sag' can trigger severe, relentless headaches, and can also cause vision and hearing disturbances, seizures and other symptoms such as neck pain and a heightened sense of smell," explains Wouter I.

Intracranial hypertension is classified in four forms based on the etiopathogenesis: parenchymatous intracranial hypertension with an intrinsic cerebral cause, vascular intracranial hypertension, which has its etiology in disorders of the cerebral blood circulation, meningeal intracranial hypertension and idiopathic ...

Historically, dehydration was considered a mechanism for spontaneous CSF hypotension due to reduced blood flow and subsequent reduction CSF secretion [29].

The 95th percentile values were 116 mg/dL for infants 0 to 28 days and 80 mg/dL for infants 29 to 56 days. The 95th percentile values by age category were as follows: ages 0 to 14 days, 117 mg/dL; ages 15 to 28 days, 107 mg/dL; ages 29 to 42 days, 96 mg/dL; and ages 43 to 56 days, 74 mg/dL.

Back pain, limb pain, and limb numbness were inversely associated with CSF leaks (p = 0.042, p = 0.045, and p = 0.006, respectively).

Does drinking water hydrate your spine? ›

When we don't drink enough water, the body suffers. Good spinal health begins with good hydration. The spine is constructed in such a way that dehydration can cause limited mobility, decreased flexibility, and pain. It can cause the spine to age faster than it should which impacts the entire body.

POTS, orthostatic hypotension, cervicogenic headache, vestibular migraine, and prior Chiari decompression surgery are all causes of orthostatic headache that may mimic spinal CSF leak and must be distinguished for patients to receive appropriately directed therapy.

What causes a cerebrospinal fluid leak? Some CSF leaks occur spontaneously and the cause is unknown, while others are a result of trauma such as a head injury, brain or spinal surgery, an epidural, a lumbar puncture (spinal tap) or a skull base tumor.

CSF leaks, hydrocephalus, Chiari malformation and Syringomyelia fall under the umbrella of CSF disorders. This happens when the cerebrospinal fluid (CSF) builds up, putting pressure on the brain and leading to damage.

Surgery is a common method to repair CSF leaks. The surgery can either directly close a leak or help reconstruct a damaged area when the leak is from a significant injury. Some surgeries may go through your skull to access a leak, while others might try to repair a leak through your nose or mouth.

Spinal tap and MS diagnosis

Results indicating MS may include: Presence of oligoclonal bands, a group of proteins (called immunoglobulins) that show inflammation in the central nervous system. High levels of immunoglobulin G (IgG) antibodies. People with low levels of IgG are more prone to infections.

Magnetic resonance imaging (MRI) accurately detects CSF leaks and associated complications such as the encephaloceles and meningoceles.

It is important to note that imaging of patients with spinal CSF leaks may sometimes be normal, and an MRI is not solely adequate in diagnosing a spinal CSF leak. Spinal CSF leaks can exist without any evidence of a leak on imaging. A negative MRI of the brain or spine does not rule out a spinal CSF leak.

In general, your CSF analysis results may show that you have an infection, an autoimmune disorder, such as multiple sclerosis (MS), or another disease or injury of the brain or spinal cord. Your provider will likely order more tests to confirm your diagnosis.

In MS, damage to myelin causes certain types of proteins to be released into the spinal fluid. When these proteins are identified in the spinal fluid, but not in the blood, MS is thought to be one of the possible diagnoses. Spinal fluid is obtained through a lumbar puncture (also known as a spinal tap).

What mimics MS? ›

These include fibromyalgia and vitamin B12 deficiency, muscular dystrophy (MD), amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease), migraine, hypo-thyroidism, hypertension, Beçhets, Arnold-Chiari deformity, and mitochondrial disorders, although your neurologist can usually rule them out quite easily.

There are no specific tests for MS . Instead, a diagnosis of multiple sclerosis often relies on ruling out other conditions that might produce similar signs and symptoms, known as a differential diagnosis. Your doctor is likely to start with a thorough medical history and examination.

Also, these signs can show up in a number of other diseases, too. So a spinal tap by itself can't confirm or rule out a diagnosis of multiple sclerosis.

If a patient does have lesions in the spinal cord, he/she may be said to have Spinal MS. A smaller number of MS patients, approximately 20 percent, may have only spinal lesions and not brain lesions. I am an example of one of those 20 percent of MS patients who only have spinal lesions.

Often, the more convenient MRI scans is performed instead of the lumbar puncture. While MRI has become the most commonly used surrogate marker for MS, it is neither 100 percent sensitive nor 100 percent specific. The lumbar puncture remains a simple examination that yields valuable information.

Normally, there are no RBCs in the cerebrospinal fluid, and there should be no more than five WBCs per cubic millimeter of CSF. If your fluid contains RBCs, this may indicate bleeding. It is also possible that you had a traumatic tap (blood leaked into the fluid sample during collection).

Specimen Requirements:

Collect a minimum of 3 mL of CSF. If flow cytometry for lymphoma/leukemia is required, provide as much specimen as possible (CSF for flow cytometry must be submitted fresh).

In general, 0.5 to 1 mL of CSF is adequate for routine diagnostic tests, including cell counts, protein concentration, and cytological analysis. Larger volumes are necessary for additional diagnostics (cultures, titers, polymerase chain reaction [PCR], flow cytometry, protein electrophoresis, etc.).

Ideally a minimum volume of 1mL is required for microscopy and culture.

How many cells are enough for flow cytometry? ›

Cell Concentration/Cell number:

For each sample, you will need between 10^5 and 10^6 cells. If you are new to flow cytometry, use the higher number of cells -- to give yourself a margin for error (you always lose more cells than you expect during the staining and washing procedures).

The recommended cell concentration is 1 x 106/ sample, but 5 x 105/sample is the minimum required. Cells should be suspended in a volume of 0.25 ml – 1.0 ml. In case of live cells a viability dye should be used to exclude dead cells with higher autofluorescence from the analysis.

In the flow cytometer, particles are carried to the laser intercept in a fluid stream. Any suspended particle or cell from 0.2–150 micrometers in size is suitable for analysis.

Cerebrospinal fluid (CSF) has essential biochemical and mechanical functions. CSF is produced at a rate of around 500 ml/day; there are estimates that there is approximately 125 mL to 150 mL of CSF in the body at any given time.

As with most cytologic specimens, CSF cytology results are commonly reported as either “negative for malignancy,” “atypical,” “suspicious,” or “positive.” Over 90% of CSF specimens are assigned a cytologic diagnosis of “negative for malignant cells.”¹⁷ Many show only a small number of lymphocytes and monocytes, ...

Normal Results

A normal result means no bacteria, viruses, or fungi grew in the laboratory dish. This is called a negative result. However, a normal result doesn't mean that an infection is present. The spinal tap and CSF smear may need to be done again.

In bacterial meningitis, the CSF glucose level (reference range, 40-70 mg/dL) is less than 40 mg/dL in 60% of patients. A simultaneous blood glucose determination should be obtained for the purposes of comparison.

If there is no growth, the test is considered normal, or negative. The test is considered positive if bacteria, viruses, or fungi are detected in your CSF. This means there is an infection.

The CSF is continually produced, and all of it is replaced every six to eight hours.

How accurate is a lumbar puncture? ›

Radiological studies have shown that this clinical landmark is accurate in over 95% of the population,¹⁰ although in females or obese people Tuffier's Line tends to be found at a higher level than L4.

The desired insertion point of the needle is the L3-L4 or L4-L5 interspace; thus, the needle is inserted below the level of the spinal cord. The spinous process of L4 lies along an imaginary line between the top of the posterior superior iliac crests.