Synovial Fluid Analysis

Synovial fluid functions

- Lubrication

- Friction reduction

- Transportation

What is synovial fluid composed of?

Glucose, electrolytes, uric acid

The levels of protein and immunoglobulins in synovial fluid are ______ that of blood plasma.

1/4-1/2

Arthritis is damage to the articular ______ and synovial ______ that produces pain and stiffness.

cartilage, membrane

Synovial fluid is collected via ______.

arthrocentesis

Normal synovial fluid does not ______.

clot

During arthrocentesis, a ______ moistened syringe is inserted into the joint and fluid is extracted

sterile

The needle is moistened with ______.

sodium heparin (or EDTA)

______ and ______ can't be used to moisten the needle for arthrocentesis. Why?

Oxalate, lithium heparin

These can cause structures that look like crystals

______ tubes of synovial fluid are collected each time.

3 (5-10mL each)

What departments do the different tubes of synovial fluid go to?

1 - Hematology

2 - Microbiology

3 - Miscellaneous

Hematology will perform ______ and ______ on synovial fluid.

cell count, microscopic examination

Microbiology will perform ______ and ______ on the sterile tube of synovial fluid.

culture, gram stain

The miscellaneous tube of synovial fluid is ______ to remove cells that can alter the chemical composition.

centrifuged

What are the 5 classifications of joint disorders?

- Non-inflammatory

- Inflammatory

- Septic

- Crystal induced

- Hemorrhage

What diseases fall under the category of degenerative, non-inflammatory joint disorders?

- Osteoarthritis

- Traumatic arthritis

- Early rheumatoid arthritis

- Rheumatic fever

- Sickle cell disease

What diseases fall under the category of immunological, inflammatory joint disorders?

- Rheumatoid arthritis

- Ulcerative colitis

- SLE

- Scleroderma

- Ankylosing spondylitis

- Lyme disease

- Reiter's syndrome

Inflammation will cause synovial fluid to be ______ in color.

deep yellow

Reiter's syndrome results for a preceding ______, causing pain and arthritis accompanied with ______.

infection, swelling

What microbial infections fall under the category of septic joint disorders?

- Pyogenic bacterial infections

- Mycobacteria

- Fungal

- Viral

- Spirochetal

Infection will cause synovial fluid to be ______ in color.

green

What diseases fall under the category of crystal-induced joint disorders?

- Gout

- Pseudogout

Crystals will cause synovial fluid to be ______ in color.

milky/white

What underlying bleeding disorders fall under the category of hemorrhagic joint disorders?

- Traumatic joint injuries

- Hemophiliac arthropathy

- Coagulopathies

- Tumors

True hemorrhage will show ______ red color distribution.

even

Cloudy synovial fluid indicates the presence of ...

Cells, cellular debris, clots

_______ is what causes the high viscosity of synovial fluid.

Hyaluronic acid

Viscosity can be lowered by adding ______.

hyaluronidase

Hyaluronidase is secreted by ______ present during inflammation and by some ______.

neutrophils, bacteria

Viscosity can be measured manually by ______.

string length

In order to count WBCs, ______ saline is added to lyse the RBCs present.

hypotonic

In order to count RBCs, ______ saline is added to avoid their lysis.

isotonic

What is the normal range of WBCs in synovial fluid?

0-200ul, <25% PMNs

RBCs can be present with ...

- Infection

- Hemorrhage

- Traumatic tap

A differential on synovial fluid requires an initial ______.

cytospin

Normal values of PMNs, lymphocytes, and macrophages in synovial fluid

PMNs: <25%

Lymphocytes: <15%

Macrophages: <70%

PMNs are increased in synovial fluid with ...

- Bacterial sepsis

- Crystal induced inflammation

Lymphocytes are increased in synovial fluid with _______.

nonseptic inflammation

Macrophages are increased in synovial fluid with ______ conditions.

viral

What are some abnormal cells that can be seen in synovial fluid?

- Eosinophils

- LE cells

- Reiter cells

- Chondrocytes

- RA cells (ragocytes)

RA cells (ragocytes)

Neutrophils with small dark cytoplasmic granules of Ig

RA cells are present in ______ and with ______ complexes.

rheumatoid arthritis, immune

Reiter cells

Macrophage with ingested PMNs

Reiter cells are present in Reiter's syndrome and ______.

nonspecific inflammation

Chondrocyte

Large and multinucleated

Chondrocytes are seen with ______.

osteoarthritis

LE cell

PMN with ingested nucleus

LE cells are seen with ______.

Lupus erythematous

Degradation of RBC products

RBC --> hemoglobin --> hemosiderin --> hematin crystal

Hemosiderin

Hematin crystal

Orange

Monosodium Urate (MSU) crystals

Needle shaped; intracellular or free

MSU crystals are indicative of ______.

gout

Gout is a type of arthritis that exhibits ______.

hyperuricemia

Hyperuricemia results from a buildup of too much ______, forming MSU crystals and inflammation.

uric acid

Episodes of gout are caused by increased ______ production.

urate

Gout affects middle aged men and ______ women.

post-menopausal

Calcium pyrophosphate crystals

Rhomboid, intracellular or free

Calcium pyrophosphate crystals are indicative of ______.

pseudogout

Pseudogout is a degenerative arthritis that involves attack less painful and longer than ______.

gout

Cholesterol crystals

Cholesterol crystals are seen extracellularly with ______.

Rheumatoid arthritis

Hydroxyapatite crystals are seen with ______ deposits in the joints.

calcified

Corticosteroid crystals

Intracellular

Normal synovial fluid should have the same ______ level as serum.

glucose

Normally and with non-inflammatory conditions cause a serum/synovial fluid glucose difference of ______.

<10mg/dL

A decrease in glucose is indicative of ______ conditions.

inflammatory

Glucose collection should involve ______ to prevent glycolysis.

NaF

Normal lactate synovial fluid level

<25mg/dL

Lactate is elevated in ______.

septic arthritis (up to 1000mg/dL)

Normal synovial fluid contains less than ______ or 1/3 serum protein.

3g/dL

Protein increases with ______ and ______ disorders.

inflammatory, hemorrhagic

LD is increased in ...

RA, infectious arthritis, gout

Uric acid in synovial fluid is significantly lower than serum with ______ disease.

inflammatory

High uric acid supports a diagnosis of ______.

gout

What bacteria are normally responsible for causing an infection of synovial fluid?

- Staphylococcus

- Steptococcus

- Haemophilus

- Neisseria