(P) Lec 5: Body Fluid Analysis (Others) Flashcards
- An ultrafiltrate of plasma
- Flows between 2 membranes (parietal and visceral)
- Can be pleural, peritoneal, or pericardial in nature
Serous Fluid
Serous Fluid
Refers to the accumulation of serous fluids
Effusion
Serous Fluid
Causes of Effusion:
1. Increased ____ pressure
2. Decreased ____ pressure
3. Increased capillary ____
4. ____ obstruction
- Hydrostatic
- Oncotic
- Permeability
- Lymphatic obstruction
Serous Fluid
Give the 3 methods of serous fluid collection
- Paracentesis (peritoneal)
- Pericardiocentesis (pericardial)
- Thoracentesis (pleural)
Serous Fluid
Transudate vs. Exudate?
- There is disruption of fluid filtration and reabsorption
- No direct involvement of the membranes
- Caused by CHF, liver cirrhosis, hyperproteinemia, and nephrotic syndrome
Transudate
Serous Fluid
Transudate vs. Exudate?
- Inflammatory processes that result in damage to blood vessel walls
- Body cavity membrane damage
- Decreased reabsorption by the lymphatic system
- There is direct involvement and injury to the membranes
- Caused by infections, inflammation, malignancy, infarction, and hemorrhages
Exudate
Serous Fluid
Give the appropriate preservatives for the ff. tests:
1. Cell count and differential count
2. Chemical serology, microbial, and cytologic analysis
3. For pH determination
- EDTA
- Heparin
- Ice
Serous (Pleural) Fluid
This criteria helps differentiate pleural exudates from transudates:
- Pleural fluid/serum protein ratio > 0.5
- Pleural fluid/serum LDG ratio > 0.6
- Pleural fluid LDH should be > 2/3 the normal upper limit for serum (> 200 IU/L)
Light’s Criteria
Serous (Pleural) Fluid
Give the ff. chemical examination analytes:
1. Decreased in infection or inflammation
2. Increased in infection and inflammation
3. Increased in pancreatitis
4. Increased in thoracic duct damage
- Glucose
- Lactate
- Amylase
- Triglycerides
Serous (Pleural) Fluid
What pH levels correspond to:
- Infection
- Esophageal rupture
- < 7.2
- < 6.0
Serous Fluid
Refers to excess peritoneal fluid (>50mL)
Ascites (Ascitic fluid)
Serous (Peritoneal) Fluid
- A method for differentiating T and E
- You subtract the fluid albumin from the serum albumin
Serum–Ascites Albumin Gradient (SAAG)
Serous (Peritoneal) Fluid
Transudate or Exudate?
1. SAAG of 1.1 g/dL or greater
2. SAAG of less than 1.1 g/dL
- Transudate
- Exudate
Serous (Peritoneal) Fluid
What 2 markers indicate malignancy?
CEA and CA125
Serous (Peritoneal) Fluid
Transudate or Exudate?
- Portal hypertension
- Obstructions to hepatic flow (cirrhosis)
- Congestive heart failure
- Hypoalbuminemia
Transudate
Serous (Peritoneal) Fluid
Transudate or Exudate?
- Metastatic ovarian, prostate, and colon cancer
- Infective peritonitis
Exudate
What is the other name for Hemolytic Disease of the Fetus and Newborn (HDFN)?
Erythroblastosis Fetalis
HDFN
This test provides a measure of the severity of red cell destruction caused by the incompatibility of the maternal & fetal blood
Bilirubin Test
HDFN
Bilirubin Test:
1. Specimen must be protected from ____
2. Perfomed through ____ analysis
3. Absorbance is measured from ____ to ____ nm
4. The absorbance peak is seen at ____ nm
5. The bilirubin concentration is the change at ____ nm
- Light
- Spectrophotometric
- 550nm to 350nm
- 450nm
- 450nm
HDFN
What are the 2 methods used for the spectrophotometric determination of bilirubin?
Liley and Freda’s Methods
Study the graphs in the PPT
HDFN
Causes for interference (give the body fluid):
1. An increased absorbance at 410-415nm
2. Produces a broad curve; confirmatory tests include creatinine, urea, and protein
3. A greenish substance producing a flat absorbance curve
- Blood
- Urine
- Meconium
Refers to a phenomenon when the neural tube (what forms the early brain and spine) does not close properly
Neural Tube Defects (NTD’s)
NTD’s
Give the neural tube defects:
1. Absence of a large part of the brain and the skull
2. Fetal spinal column doesn’t close completely during the first month of pregnancy
- Anencephaly
- Spina bifida
NTD’s
Tests for Neural Tube Defects
- This is produced by the fetal yolk sac and liver; a major protein of the fetal liver prior to 18 weeks
- Is detectable for a maximum of 12-15 weeks and then afterwards, it will decline
- An increased level of this is correspondent to multiple pregnancies and neural tube defects
Alpha-feto Protein (AFP)
NTD’s
Alpha-feto Protein (AFP); increased or decreased maternal serum AFP?
- Abdominal hernia
- Cystic hygroma
Increased
NTD’s
Alpha-feto Protein (AFP); increased or decreased maternal serum AFP?
- Down’s syndrome
- Aneuploidies
Decreased
NTD’s
TOF: In neural tube defects, AFP is increased in maternal serum but decreased in the amniotic fluid due to dilution
False (increased in both)
NTD’s
Protocol for AFP Testing (Quadruple Testing):
Maternal serum is tested for AFP along with what 3 other analytes?
HCG, Estriol, and Inhibin
NTD’s
Protocol for AFP Testing (Quadruple Testing):
To diagnose Down’s Syndrome, what should be elevated?
Inhibin and Beta HCG
NTD’s
Protocol for AFP Testing (Quadruple Testing):
To diagnose Down’s Syndrome, what should be decreased?
AFP and Estriol
NTD’s
Protocol for AFP Testing (Quadruple Testing):
If found positive for the preliminary tests, what should be done next?
Repeat and perform diagnostic ultrasound
NTD’s
This procedure is for confirmation during AFP testing
Amniocentesis
NTD’s
This is the confirmatory procedure to detect NTDs
Amniotic Fluid Alpha-Fetoprotein (AFAFP) Testing
NTD’s
- What is the normal AFP value according to gestational age?
- This is the laboratory’s reference level for a given week of gestation
- < 2.0 MoM (Multiples of Median)
- Median
- An enzyme present in nervous tissue, muscles, and RBCs
- The CNS-specific variant of this analyte is more specific but not done on bloody specimen
- Tests to be done include: enzymatic, immunologic, and electrophoretic with inhibition
Acetylcholinesterase (AChE)
Fetal Lung Maturity
- This is a complex substance containing phospholipids
- It is produced by Type II alveolar cells and it lines the alveoli and bronchioles
- Functions to lowers the surface tension/prevent alveolar collapse
Surfactants
Fetal Lung Maturity
Atelectasis is synonymous to?
Lung collapse
Fetal Lung Maturity
A decreased surfactant level causes what syndrome?
Neonatal Respiratory Distress Syndrome (Hyaline Membrane Disease)
Fetal Lung Maturity
Give the 4 phospholipids measured in amniotic fluid (and give what is the most important)?
■ Phosphatidylcholine (PC, lecithin)
■ Phosphatidylglycerol (PG)
■ Phosphatidylinositol
■ Sphingomyelin (SP)
Note: LECITHIN is the most important
Fetal Lung Maturity
Surfactants are made up of how many percent phospholipids and protein?
- 90% phospholipids
- 10% protein
Fetal Lung Maturity
These provide a direct physical measure of amniotic fluid to assess the surfactant’s ability to decrease surface tension
Functional Assays
Fetal Lung Maturity
What are the 2 functional assays?
- “Bubble or Shake” Test
- Foam Stability Index (FSI)
Fetal Lung Maturity
What are the 3 quantitative tests?
- Lecithin-sphingomyelin ratio (L/S ratio)
- Phosphatidylglycerol (PG)
- Lamellar body counts
FLM Testing
Amniotic fluid + 95% ethanol → shake for 15 seconds → stand for 15 minutes
Foam Shake Test (Bubble Test)
FLM Testing
- What is the anti-foaming agent in the Foam Shake Test?
- What is the normal result of the test?
- Alcohol
- Continuous line of bubbles (indicates sufficient amounts of phospholipids)
FLM Testing
0.5mL of amniotic fluid to 0.42 to 0.55mL in 0.01mL of 95% ethanol
Foam Stability Index
FLM Testing
What is the normal value for the Foam Stability Index?
> 0.47
FLM Testing
This is the gold standard as it is a primary component of surfactants
Lecithin-Sphingomyelin Ratio (L/S Ratio)
FLM Testing (Lecithin-Sphingomyelin Ratio)
- ____ is slowly produced before 35 weeks but then increase after that
- ____ is constantly produced after 26 weeks
- Lecithin
- Sphingomyelin
FLM Testing (Lecithin-Sphingomyelin Ratio)
Give the corresponding ratios:
1. Before 35 weeks
2. After 35 weeks
- < 1.6
- > 2.0
FLM Testing (Lecithin-Sphingomyelin Ratio)
What can be 2 causes of error for this test?
Blood and Meconium
FLM Testing (Lecithin-Sphingomyelin Ratio)
What is the method used for this test?
Thin Layer Chromatography (TLC)
FLM Testing
- Uses the amniostat-FLM method
- It is rapid, uses antisera, and is not affected by blood and meconium
- Diabetic mothers display a delayed development of this analyte
Phosphatidylglycerol (PG)
FLM Testing
- Refers to packets of surfactant released by Type II cells (almost the size of platelets)
- Are counted using the platelet channels of hematology analyzers
Lamellar Body Counts (LBCs)
Sweat Analysis
- Autosomal recessive inherited disease
- Affects exocrine glands
- Causes electrolyte and mucous secretion abnormalities
- Manifests with increased sweat electrolytes, viscous lung secretions, and pancreatic insufficiency
Cystic Fibrosis (mucoviscidosis)
Sweat Analysis Measurement
Testing for this analyte is most useful for the diagnosis of CF in children as there is significantly elevated levels of this analyte
Chloride
Sweat Analysis Measurement
CF in children caused by defective chloride channels (cystic fibrosis transmembrane conductance regulator) manifests with a chloride level of what?
Above 60 mmol/L
Sweat Collection Procedure
- This uses an electric current that causes pilocarpine to migrate into the skin area (inside of forearm)
- A special sweat collection device is attached to the clean skin surface
Pilocarpine Nitrate Iontophoresis Method of Gibson and Cooke
- A viscous fluid found in the cavities of movable joints
- An ultrafiltrate of plasma with hyaluronic acid
- Collection is through arthrocentesis
- Macroscopic apperance: clear, colorless to pale yellow, and viscous
Synovial Fluid
Synovial Fluid
Give the appropriate preservative for collection:
1. For culture
2. For microscopic analysis
3. For glucose analysis
4. The anticoagulant of choice
- Heparin or Sterile tube
- Heparin or Liquid EDTA
- Fluoride
- Heparin
Note: Powdered anticoagulants should not be used
Synovial Fluid Chemical Examination
Give the normal values of the ff. parameters:
1. Total protein level?
2. Glucose level?
3. Uric acid?
4. Lactate?
- 1 to 3 g/dL
- Less than 10 mg/dL lower than serum levels (a 0.9:1 ratio to plasma glucose)
- 6 to 8 mg/dL
- Less than 25 mg/dL
Synovial Fluid Chemical Examination
Increased or Decreased Synovial Fluid?
- Inflammation (gout, RA, and SLE)
- Sepsis (bacterial and viral arthritis)
Decreased
Synovial Fluid Chemical Examination
SF uric acid is (increased/decreased) in gouty arthritis
Increased
Synovial Fluid Chemical Examination
SF lactate is (increased/decreased) in RA, infectious arthritis, and gout
Increased
Synovial Fluid Chemical Examination
This factor is seen in Rheumatoid Arthritis
Rheumatoid Factor (RF)
