Body Fluids - FFB

CSF is the result of ___ of blood/plasma that provides essential support to the brain + spinal cord

Ultrafiltration

CSF - produced in choroid plexuses of the spinal cord + brain where the ____ prevents the passage of most molecules from plasma

Blood Brain Barrier

CSF is continuously flowing through the _____

Arachnoid space

CSF Functions:

Supply nutrients

Remove wastes

Temperature regulation

Physical / mechanical barrier

CSF Tubes - Department + Storage Temp

Tube 1 - Chemistry + Serology - Frozen

Tube 2 - Microbiology - Room Temp

Tube 3 - Hematology - Refrigeration

Tube 4 - Back up + some Microbiology - Room Temp

Traumatic Tap vs Intracranial Hemorrhage

CSF Chemistry - Protein, Glucose, Lactate, Glutamine

Protein - 15-45 mg/dL - Increased in meningitis, hemorrhage, MS - Decreased in CSF leakage

Glucose - 60-70% of blood levels - Decreased in Bacterial, tubercular, or fungal meningitis

Lactate - 10-24 mg/dL - Increased in Meningitis (>35 mg/dL = bacterial, 25-34 mg/dL = fungal or tubercular)

Glutamine - 8-18 mg/dL - Increased in >35 mg/dL = coma, Reye syndrome

Meningitis - Bacterial, Viral, Tubercular, Fungal

CSF Protein - CSF / Serum Albumin Index

CSF albumin (mg/dL) / Serum albumin (g/dL)

>9 represents a compromised BBB

<9 represents an intact BBB

CSF Protein - IgG Index

(CSF IgG / Serum IgG) / (CSF albumin / Serum albumin)

<0.70 - no IgG made within the CNS so it must be coming from elsewhere

>0.70 - indicates IgG is being made from within the CNS ex: multiple sclerosis

Synovial Fluid Crystals

Monosodium urate (MSU) - Gout - Needle-shaped - Birefringence negative → when compensator is parallel to the crystal (slow), the crystal is yellow, when compensator is perpendicular to the crystal (fast) the crystal is blue

Calcium pyrophosphate (CPPD) - Pseudogout - Rhomboid or rods/needles - Birefringence positive → when compensator is parallel to the crystal (slow), the crystal is blue, when compensator is perpendicular to the crystal (fast) the crystal is yellow

Serous Fluid - Two Membrane Linings

Parietal membrane is the outmost membrane that lines the cavity wall

Visceral membrane is the innermost membrane that directly covers the organs within the cavity

Serous fluid is a plasma ultrafiltrate regulated by ______, _____, + ______

Colloidal pressure (capillary permeability), hydrostatic pressure, oncotic pressure

Effusion - Transudate vs Exudate

Pleural Fluid (lung) - Cells + Disorders

Amniotic Fluid Functions:

Provide protection + cushion to the fetus

Allow for fetal movement

Relegate temperatures

Allow for fetal lung maturity/development

Durine the first trimester, amniotic fluid is similar to _____ + during development, amniotic fluid becomes more like ____

Maternal Plasma

Urine

Amniotic fluid volume ____ due to ____

Increases

Fetal urine

Creatinine usage for amniotic fluid

May be used to determine gestational age of fetus (<36 weeks = 1.5-2.0 mg/dL, >36 weeks = >2.0 mg/dL)

May be used to differentiate maternal fluid from amniotic fluid (amniotic fluid = <3.5 mg/dL + UREA <30 mg/dL, Urine = 10 mg/dL + UREA up to 300 mg/dL)

Amniotic Fluid Testing

Triple Marker Screening (Amniotic Fluid)

Liley Graph (Amniotic Fluid)

Zone I - slight bilirubin increase w/ mild effect on fetus; no intervention

Zone II - moderate hemolysis + careful monitoring for worsening conditions, but no intervention; higher probability of early/induced labor + exchange transfusion upon delivery

Zone III - severe hemolysis + high bilirubin levels are affecting fetal health; Reflex to FLM testing, intervention is required through induction of labor or intra-uterine exchange transfusions

Vaginal Fluid Used in Clinical Laboratory Testing to Diagnose:

Infections

Pregnancy Complications

Forensic/crime Investigations

Normal Flora of Vaginal Fluid

Lactobacillus + squamous epithelium

Vaginal Fluid Cells - Clue cells, Parabasal, Basal

Clue cells - pathogenic = seen in bacterial infections, squamous cell coated in bacteria

Parabasal - desquamative inflammation vaginitis (DIV)

Basal - not normally seen in vaginal fluid + indicate altered vaginal flora like DIV

Trichomoniasis

STI due to parasitic protozoan

Green to yellow frothy discharge

Candidiasis

Yeast infection

White “curd-like” discharge

KOH prep + gram stain will reveal yeast + possible hyphae elements

Desquamative Inflammatory Vaginitis (DIV)

Beta hemolytic Streptococcus (Group A/B) or Atrophic vaginitis from decreased estrogen

High WBCs, RBCs, parabasla, + basal cells w/ little to no normal flora

Atrophic Vaginitis

Postmenopausal syndrome causing the thinning of vaginal mucosal lining due to decreased estrogen levels

pH >4.5 w/ negative amine test + change normal flora

Vaginal Infections Compared

Seminal Fluid - Physiology

Seminal Fluid - Fractions

Seminal Fluid 2 Portions

First/early portion contains: spermatozoa, low first portion = decreased sperm count

Second/later portion: most of the semen volume is present, low second portion = higher sperm count

Seminal Fluid - Collection

Following sexual abstinence of at least 2 days but no more than 7 days

Two abnormal samples (of 3) is considered significant

Sterile container, kept at room temp, + delivered to lab within 1 hour

Gastric acid is one of the main secretions of the stomach, produced by the ______

Parietal cells

Excess gastric acid (HCL) production is seen in gastrulas like:

Zollinger-Ellison syndrome

Reasons for Performing Gastric Analysis Include:

Detect gastrin secreting tumors (Zollinger-Ellison syndrome)

Detect recurrent peptic ulcer disease

Evaluating hyperacidity

Evaluating effectiveness of surgery to reduce acid output

Diagnosis of achlorhydria

Detect delayed gastric emptying

Diagnosis of upper GI hemorrhage

Sweat Test

Measures amount of salt chemicals (sodium + chloride) in sweat via pilocarpine iontophoresis

Helps diagnose Cystic Fibrosis

>60 = positive

40-60 = borderline

<40 = negative

Cystic Fibrosis

Genetic disorder that affects mucus membranes of the lungs, pancreas, + other organs as a chronic disease

Caused by mutation to CFTR gene, creating dysfunction CFTR protein (CFTRdelta508) + thus a loss of chloride channel functionality

Secretory Diarrhea

Increased secretion of water from external forces/circumstances, overriding the excess water reabsorption of the large intestine

Osmotic Diarrhea

Caused by poor absorption where excess solutes in the intestinal lumen draw water into the intestines due to incomplete food breakdown

Maldigestion - impaired food digestion

Malabsorption - impaired nutrient absorption

Altered Motility Diarrhea - Rapid gastric Emptying (RGE)

Hypermotile stomach + shortened gastric emptying + is associated w/ early dumping syndrome (EDS)

Fecal Fluid Testing - Fecal Leukocyte Testing

For neutrophils, indicative of invasive bacteria

Fecal Fluid Testing - Muscle Fiber Testing

Identifying undigested fibers useful to diagnose pancreatic insufficiency or cystic fibrosis

Undigested fibers have striations running vertically + horizontally

Fecal Fluid Testing - Fat Testing

Stool w/ steatorrhea can be screened for the presence of excess fecal fats

Indicates pancreatic insufficiency or small bowel disease

Associated w/ osmotic diarrhea (maldigestion + malabsorption)

3 day sample collection to quantify

Fecal Fluid Testing - Occult Blood Test

Detect “hidden” blood within fecal matter

Associated w/ colorectal cancer

Fecal Fluid Testing - APT Test

Determine if bloody stool is due to fetal bleed (HbF) or swallowing of maternal blood during birth (HbA)