COMMON LEARNING
ISSUES
PBL TEST 1 2012
ALPHA FETOPROTEIN
 USED AS A SCREENING MARKER INDICATING INCREASED RISK
FOR BIRTH DEFECTS (NEURAL TUBE, BODY WALL, AND
CHROMOSOMAL)
 PRODUCED BY FETAL LIVER AND YOLK SAC IF THERE IS A BODY
WALL DEFECT THE AFP WILL LEAK INTO AMNIOTIC FLUID AND IS
PICKED UP BY MATERNAL SERUM
 ALSO ASSOCIATED WITH TUMOR MARKERS, HEPATOMA,
TERATOMA, HODGKINS, LYMPHOMA, AND RENAL CELL CARCINOMA
ALPHA-FETOPROTEIN
 NORMAL FINDINGS < 40 ng/mL
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Child < 30 ng/mL
Ranges vary by week of gestation normally detected at 10 weeks
Peak levels at 16-18 weeks
 DECREASED LEVELS:
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TRISOMY 21
FETAL WASTAGE
 INCREASED LEVELS:
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NTD, ABDOMINAL WALL DEFECTS
MULTIPLE FETUSES
THREATENED ABORTION
FETAL DISTRESS OF CONGENITAL ANOMALIES
FETAL DEATH
ANTINUCLEAR ANTIBODY
(ANA)
 Used to diagnose systemic lupus erthematosus (SLE) and other
autoimmune disease
 ANA is a group of protein antibodies that react against cellular
nuclear material
 Normal findings negative at 1:40 dilution
ARTERIAL BLOOD GASES
 Monitor patients on ventilators, monitor critically ill nonventilator
patients, establish preoperative baseline parameters, and regulate
electrolyte therapy
 pH –log[H+]
• Acids normally found in blood: carbonic, dietary, lactic and ketoacids
• Elevated indicates alkalosis
• Decreased indicates acidosis
BLOOD GASES
 PCO2
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Measure of partial pressure of carbon dioxide in the blood
Measure of ventilation
10% free floating in plasma, 90% carried by RBCs
Respiratory component of acid-base determination
Co2 and pH are inversely proportional
BLOOD GASES
 HCO3- or CO2 content
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Measure of the metabolic component of the acid-base equilibrium
Regulated by the kidney
Directly proportional to pH
In alkalosis kidneys excrete more into the urine to lower pH
 PO2
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Pressure of oxygen dissolved in plasma
Indirect measure of O2 content
Determines effectiveness of oxygen therapy
Determines the force of oxygen to diffuse across the pulmonary alveoli
membrane
BLOOD GASES
 Oxygen saturation
• Percentage of hemoglobin saturated with oxygen
• As PO2 decreases so does saturation of hemoglobin
 Oxygen content
• The amount of oxygen in the blood
• Nearly all of it is bound to hemoglobin
 Base excess/deficit
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•
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Amount of
anions in the blood, bicarbonate being the largest
Also hemoglobin, proteins, phosphates
Negative base excess indicates acidosis, positive alkalosis
BLOOD GASES
 Alveolar to arterial oxygen difference
• If gradient is abnormally high there is a problem in diffusing oxygen
across the alveolar membrane (thickened or edematous) or
unoxygenated blood is mixing with oxygenated
• Thick walls due to edema, fibrosis, and RDS
• Mixing occurs with septal defects, shunts or underventilated alveoli
still being perfused
KAROTYPE
 Study an individual’s chromosome makeup to determine chromosomal defects
associated with disease or risk for developing disease
 Congenital or acquired because of duplication, deletion, translocation,
reciprocation, or genetic rearrangement
 Performed by a banding technique, pairing similar chromosomes based on size,
location of centromere, banding patterns
 Congenital anomalies, growth and mental retardation, infertility, delayed puberty,
hypogonadism, amenorrhea, ambiguous genitalia, CML, neoplasm recurrent
miscarriage, turner, klinefelter, downs
CBC
 Measures RBC
 Hemoglobin
 Hematocrit
 RBC Indices
 WBC count
 Blood smear
 Platelet count
 Mean platelet volume
CBC
 Mean corpuscular volume ( MCV)
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Average volume or size of a single RBC
Divide hematocrit by total RBC count
Large: folic acid or B12 deficiency
Small: iron deficient anemia or thalassemia
 RBC
• # circulating RBC
• Normal life span 120 days
• Lysed and extracted from circulation by spleen
CBC
 Mean corpuscular hemoglobin
• Measure of average weight of hemoglobin within RBC
 Mean corpuscular hemoglobin concentration
• Average concentration or % of hemoglobin within RBC
 RBC distribution width
• Indicates variation of size of RBC
• Important in classifying anemias
CBC
 Blood smear
• Information concerning drugs and diseases that affect RBCs and
WBCs
• Examines RBC, platelet, and WBC
 White count
• Neutrophils, basophils, eosinophils, monocytes, lymphocytes
CBC
 Platelet count
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Number of platelets formed in bone marrow of megakaryocytes
Adult/child 150,000-400,000
Newborn/ premature infant: 100,000-300,000
Infant 200,000-475,000
 Mean platelet volume
• Measure volume of large number of platelets to evaluate platelet
disorders especially thrombocytopenia
CREATININE, BLOOD

. Normal Findings:

A. Elderly: Decrease in muscle mass may cause decreased values

B. Adult: Male: 0.6-1.2 mg/dL
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C. Adolescent: 0.5-1.0 mg/dL
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D. Child: 0.3-0.7 mg/dL
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E. Infant: 0.2-0.4 mg/dL
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F. Newborn: 0.3-1.2 mg/dL

---creatinine clearance
Female: 0.5-1.1 mg/dL

1. used to measure the GFR of the kidneys

2. Normal Findings:

A. Adult (<40 yrs): Male: 107-139 mL/min

B. Values decrease 6.5 mL/min/decade of life after age 20 yrs with decline in GFR

C. Newborn: 40-65 mL/min
Female: 87:107 mL/min
CREATININE
 Catabolic product of creatine phsophate used in skeletal muscle
contraction, depends on muscle mass
 Excreted by kidneys and is directely proportional to renal excretory
function; serum levels should be constant
 Used to diagnose impaired renal function
 Unlike BUN it is minimally affected by hepatic function
 Approximation of GFR
 Suggest chronic disease
CREATININE
 In chronically unstable patients acute changes in renal function can
make real time evaluation of GFR difficult
 Cystatin C may be used for chronic kidney disease
 Clearance: amount of filtrate made
• Amount of blood to be filtered and ability of glomeruli to filter
ERYTHROCYTE
SEDIMENTATION RATE
 no-n-specific test used to detect illnesses associated with acute and chronic
infection, inflammation, advanced neoplasm, and tissue necrosis or infarction
 Measure rate at which RBC settle in saline solution or plasma per unity time
 RBC will settle faster with illness
 Male up to 15 mm/hr
 Female up to 20 mm/hr
 Child up to 10 mm/hr
 New born 0-2 mm/hr
ESTROGEN FRACTION
 Estradiol
Serum (pg/mL)
Urine mcg/ 24 hr
Child <10
<15
0-6
Adult male
10-50
0-6
Follicular phase
25-350
0-13
Midcycle peak
150-750
4-14
Luteal phase
30-450
4-10
postmenopausal
<20
0-4
Adult female
ESTROGEN FRACTION
estriol
Serum (ng/mL)
Urine mcg/ 24 hr
Male, child,
postmenopausal
1-11
Follicular phase
0-14
Ovulatory phase
13-54
Luteal phase
8-60
1st trimester
<38
0-800
2nd trimester
38-140
800-12,000
3rd trimester
31-460
5000-12,000
ESTROGEN FRACTION
Total estrogen
serum
Urine mcg/ 24hr
Male or child
4-25
Female not pregnant
4-60
1st trimester
0-800
2nd trimester
800-5000
3rd trimester
5000-50,000
ESTROGEN FRACTION
 Evaluate sexual maturity, menstrual problems, and fertility
problems
 Evaluate males with gynecomastia or feminization
 In pregnancy it indicates feto-placental health or tumor marker
 FSH and LH stimulate ovaries to make estradiol (E2)
• Peaks during ovulatory phase of menstrual cycle
• Menopausal status, sexual maturity, fertility problems, gynecomastia,
feminization syndromes, and tumor mark for ovarian tumors
ESTROGEN FRACTION
 E1 or estrone is major circulator after menopause
 E3 (estriol) major estrogen in pregnant female assess placental function and fetal
normality, produced by placenta from estrogen precursors rising values are good
declining values mean fetoplacental deterioration, preeclampsia/eclampsia, diabetes
mellitus, anencephaly, death, dysmaturity
 Increased levels liver necrosis, adrenal tumor, hepatic cirrhosis, hyperthyroidism
 Decreased: turners, failing pregnancy, hypothryoidism or pituitarism, steinleventhal syndrome, menopause, anorexia nervosa
MATERNAL SCREEN
TESTING
 Potential birth defects or serious chromosomal/genetic abnormalities
 Women over 35 for downs, NTD, or abdominal wall defects
 Double test hCG and AFP
 Triple AFP, hCG, and estriol
 Quadruple AFP, hCG, inhibin A, and estriol
 With trisomy 21 AFP levels are 25% lower than normal hCG 2x higher
 Inhibin A just like hCG
PARTIAL
THROMBOPLASTIN TIME
(PTT)
 Assess the intrinsic system and common pathway of clot formation and to
monitor heparin therapy
 First phase of reactions is intrinsic system: factor XII forms complex on
subendothelial collagen
 Extrinsic factors include thromboplastin
 Prothrombin becomes thrombin converts fibrinogen to fibrin
 Plasmin degenerates
 Evaluates fibrinogen II (prothrombin, V, VIII, IX, X, XI, and XII
 If any of these exist in inadequate quantities then PTT is prolonged
PTT
 Vitamin K deficiency can prolong PTT II, IX, and X are
dependent
 Coag factors are made in the liver so hepatocellualr disease will
prolong
 Heparin inactivates prothrombin (II) no thromoplastin
 Monitor heparin whose effects are short-lived if too much is given
protamine sulfate can reverse
HCG
 <5 for non-pregnant people, used to diagnose pregnancy, increases throughout
pregnancy, can be detected as early as 10 days post conception
 Secreted by placental trophoblast
 Immunologic test: high risk of false positive
 Beta subunit characteristic of hCG
 Radioimmunoassay: blood test for beta
 Radioreceptor assay performed in one hour reliable
 Ectopic pregnangy, hydatiform mole, and choriocarcinoma can produce
 Liver cancer cells as well
PROTHROMBIN TIME
 Adequacy of extrinsic system and common pathway
 Activation of factor X in the presence of factor V and
phospholipid and calcium
 Stimulates platelet aggregation and converst fibrinogen to fibrin in
clot stabilization
 Factors I (fibrinogen) II (prothrombin), V, VII, and X
PT
 Hepatocellular liver disease (cirrhosis, hepatitis, neoplastic invasive
processes) I, II, V, VII, IX, X
 Obstructive biliary disease bile necessary for fat absorption decreases
A,D,E and K are all fat soluble II, VII, IX, X all dependent on vitamin K,
differentiate from liver disease because it responds to vitamin K
 Coumarin ingestion (warfarin) interfere with vitamin K associated
factors; effects long lasting, can be fixed by vitamin K
RHEUMATOID FACTOR
 Negative <60 units/mL
 Used in the diagnosis of RA
 RA: morning stiffness for 6 weeks, pain in at least one joint, swelling in
at least 1 joint, symmetric bilateral joint swelling, presence of
subcutaneous nodules, radiographic changes
 Abnormal IgG made in synovial joints
 IgG and IgM along with fc attack abnormal IgG
 Immune complexes are activated and joint destruction begins
RF
 Tests mainly for identification of IgM
 Must be found in greater than 1:80 dilution
 SLE may also give false positive
 Tuberculosis, chronic hepatitis, infectious mononucleosis and
subacute bacterial endocarditis may give false reading
 Does not disappear in remission
BUN
 10-20 mg/dL adult
 Child and infant 5-18 mg/dL
 Newborn 3-12 mg/dL
 Rough and indirect measurement of renal function and GFR also a measure of
liver function
 Amount of urea nitrogen in the blood
 Urea is an end product of protein metabolism and digestion
 Elevated bun or azotemia
BUN
 Shock, dehydration, congestive heart failure, excessive protein
catabolism
 GI bleeding
 If kidney disease is unilateral and other kidney can take on role then
BUN won’t be affected
 Ureteral and urethral obstruction
 Liver disease decreased BUN
 Can be normal if there is liver and kidney disease
AMNIOCENTESIS
 Performed on women whose pregnancies are high risk (diabetic,
obese, older)
 Indicate fetal maturity, distress, risk for RDS, genetic and
chromosomal abnormalities, sex, NTD
 Lung maturity (lecithin and sphingomyelin ratio) lecithin is a major
constituent of surfactant 2:1 indicates maturity; at 35 weeks rapidly
increases
AMNIO
 Phosphatidyglycerol (PG) small component of surfactant,
produced by mature lung alveolar cells appear at 35 weeks
 Lamellar body count: produce by type II pneumocytes, represent
the storage of surfactant
 Microviscosity: aggregates dependent on L/S ratio and degree of
saturation of fatty acid side chains, high early decreases later
AMNIO
 Rh isoimmunization: assess levels of bilirubin in amniotic fluid,
indicates severity of hemolytic anermia in Rh-sensitized pregnancy higher
bilirubin, lower fetal hemoglobin, early delivery or blood transfusion may
be indicated
 Anatomic abnormalities: increased AFP neural crest abnormality
 Fetal distress: pale, straw colored fluid tinged with green, yellow
indicates blood incompatibility, yellow-brown may be intrauterine death
red is blood contamination
ECHOCARDIOGRAPHY
 Normal findings: normal position, size, and movement of cardiac
valves and heart muscle wall, normal directional flow of blood within
the heart chambers
 Performed to evaluate heart wall motion and detect valvular
disease, evaluate heart during stress testing and identify and quantify
pericardial fluid
 Ultrasound procedure to evaluate structure and function of heart
ECHO
 M-mode echocardiography recording of amplitude and rate of motion in real
time
 Two dimensional ultrasonic beam moved within one sector of the heart 3D
gives better image of heart wall and valves
 Color flow: direction and velocity of blood flow within heart and great vessels
for valve function in regards to regurgitation
 Septal defects, perfusion, valvular heart disease, prolapse, stenosis, subaortic
stenosis, tumors, aneurysm
 Perflutren (definity or optison) provides enhancement of borders
OXIMETRY
 >95% is normal
 Monitors arterial oxygen saturation in patients at risk for hypoxemia.
Surgery, cardiac stress testing, mechanical ventilation, heavy sedation, lung
function testing or trauma
 Non-invasive measures home many hemoglobin have oxygen attached
to them
 Fetal oxygen saturation monitoring: if heart is in distress but saturation
is fine you can avoid c-section, placed on cheek between 30 and 70%
EATING DISORDERS
 Anorexia nervosa: refusal to maintain body weight (BMI below 17.5), afraid of appearing fat,
frequently staving but in denial, lacking insight, brought in by family members, failure to make
expected weight gain as child or adolescent, amenorrhea, loss of libido or potency in men,
depressive mood, irritability, social withdrawal, insomnia, decreased libido, self-induced vomiting
or purging, excessive exercise, use of diuretics or appetite supressants
 Increased corticotropin releasing factor, cortisol, growth hormone, serotonin, decrease
diurnal cortisol fluctuation, LH, FSH, TSH
 Bradycardia, hypotension, arrhythmias, cardiomyopathy
 Hypokalemia, hypochloremic metabolic alkalosis, increased BUN, edema
 Dry skin dental carries, delayed gastric emptying, constipation, anemia, osteoporosis
FREMITUS
 Palpable vibrations transmitted through the bronchopulmonary tree to
the chest wall as the patient is speaking. To detect use ball or ulnar surface
of hand to optimize vibration in bones of hand. Repeat 99 or one one
one
 Is decreased or absent when the voice is soft or when the transmission
of vibrations from larynx to chest is impeded.
 Causes of faint fremitus: very thick chest walls, obstructed bronchus,
COPD, fibrosis, pleural effusion, pneumothorax or infiltrating tumor
HYPER-RESONANCE
 Very loud, lower pitch, longer duration
 Generalized hyper-resonance may be heard over the hyper-inflated
lungs of COPD or asthma, but it is not reliable
 Unilateral hyper-resonance suggests a large pneumothorax or large
air filled bulla in lung
GRAVIDA-PARA
 Gravida = total number of pregnancies
 Para = or outcomes of pregnancies
• Often after you will see notations F (full-term), P (premature), A
(abortion), L (living child)
APGAR
 Key assessment of newborn immediately after birth 5 components
take at 1 and 5 minutes after birth based on 0,1, or 2, total score is 010, five minute score of 8+ move on to full exam
 1 minute score 8-10 normal, 5-7 some nervous system depression
0-4 severe depression requiring immediate resuscitation
 5 minute score 8-10 normal, 0-7 high risk for subsequent central
nervous system and other organ dysfunction
APGAR
Clinical sign
0
1
2
Heart rate
absent
<100
>100
Respiratory
effort
Absent
Slow and
irregular
Good, strong
Muscle tone
Flaccid
Some flexion
of arms and
legs
Active
movement
Reflex
irritability
No response
Grimace
Crying
vigorously,
sneeze or
cough
color
Blue/pale
Pink body, blue
extremities
Pink all over
VITAL SIGNS
 Doppler method detects arterial blood flow vibrations, converts
them to systolic normal for males is 70 mmHg at birth 85 at 1 month
and 90 at 6 months
 Pulse is best found at femoral artery
VITAL SIGNS
age
Average heart rate
Range
Birth 0-2
140
90-190
0-6
130
80-180
6-12
115
75-155
VITAL SIGNS
 Fever can raise respiratory rates by 10 respirations per minute for each
degree centigrade of fever
 Temperature rectal, oral and auditory canal (rectal in infants)
• Usually above 99 degrees until after 3 years
• May approach 101 in normal children in late afternoon after vigorous
activity
• Above 100 <2-3 months may be a sign of a serious infetion
 Respiratory rate 30-60 per minute
• Birth – 2 months >60/minute cutoff
• 2-12 months >50/ minute cutoff
VERTEX PRESENTATION
 Presentation of any part of the fetal head during birth
 Head/neck in flexion so chin is pushed against chest
 May be different degrees of flexion
CONGENITAL ADRENAL
HYPERPLASIA
 Refers to disorders of adrenal steroid biosynthesis that result in
glucocorticoid and mineralcorticoid deficiencies
 Because of deficient cortisol biosynthesis, increases in ACTH
occurs, inducing adrenal hyperplasia and overproduction of steroids
that precede blockage of enzyme production
 21-hydroxylase (CYP21) deficiency is the most common (95%)
CAH
 Failure of CYP21 and 17 hydroxyprogesterone and progesterone
to 11 deoxycortisol and 11 deoxycorticosterone respectively with
deficient cortisol and aldosterone is to replace
 Aim of treatment for class in 21 hydroxylase deficiency is to
replace glucocorticoids and mineralcorticoids, suppress ACTH and
androgen overproduction and allow for normal growth and sexual
maturation in children
SOUTHERN BLOT
 Used for identifying DNA sequences on gels
 Produced when DNA on a nitrocellulose blot of an
electrophoretic gel is hybridized with a DNA probe
 BMP/Chem-7:
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Sodium
Chloride
Potassium
CO2/Bicarbonate
BUN
Creatinine
Glucose
BMP VS. CMP/Chem-12:
CMP
• Same as BMP plus:
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AST
ALT
Albumin
Bilirubin
Alkaline Phosphatase
SODIUM (NA)
 Normally 125-145 mmol/l
 Collect in red top tube
 Increased: Diabetes inspidius, exessive sweating, Cushing’s
syndrome
 Decreased: Excess body water (CHF, renal failure, small cell lung
cancer, brain disorders), hypothyroidism, vomiting, diarrhea,
pancreatitis
CHLORIDE (CL)
 Normally 97-107 mEq/L
 Collect in tiger top tube
 Increased: Diarrhea, hyperalimentation
 Decreased: Vomiting, renal disease, diabetic ketoacidosis
POTASSIUM (K)
 Normally 3.5-5 mEq/L
 Collect in red or tiger top tube
 Hemolysis may falsely elevate level
 Increased: Renal failure, Addison’s disease, dehydration, ACE
inhibitors, Spironolactone
 Decreased: Diuretics, NG suctioning, vomiting, diarrhea,
metabolic alkalosis
CARBON DIXOIDE (CO 2 )
 Normally 23-29 mmol/L
 Collect in tiger tube top; don’t expose to air
 CO2 excreted into blood as bicarbonate
 Increased: COPD, severe vomiting
 Decreased: Starvation, diabetic ketoacidosis, diarrhea, dehydration
BLOOD UREA NITROGEN
 Normally 5-20 mg/dl
 Collect in tiger top tube
 Increased: Renal failure, CHF, aminoglycosides
 Decreased: Starvation, liver failure
 BUN:Creatinine >20 suggests dehydration
 BUN:Creatinine >30 suggests GI bleed
CREATININE
 Normally <1.1 mg/dl
 Collect in tiger or red top tube
 Measures blood flow through kidneys
 Increased: Renal failure, false positive seen in diabetic ketoacidosis
 Decreased: Muscle wasting, liver disease
GLUCOSE
 Normally 80-140 mg/dl
 Collect in red or tiger top tube
 Slight increase normal with aging
 Increased: DM, Cushing’s syndrome, pancreatitis, thiazide
diuretics
 Decreased: Liver disease, malnutrition, sepsis, endocrine tumors
AST/ALT
 Aspartate Aminotransferase:
 Alanine Aminotransferase:
• Normally 7-42 IU/L
• Increased: Liver disease, muscle
trauma, burns
• Decreased: Vitamin B6 deficiency,
dialysis
• AST>ALT in alcoholic hepatitis
• Normally 1-45 IU/L
• Increased: Liver disease, billary
obstruction
• ALT>AST in viral hepatitis
ALBUMIN
 Normally 3.5-5 g/dl
 Collect in tiger top tube
 Best lab test for measuring protein
 Decreased: Malnutrition, nephrotic syndrome, alcoholic cirrhosis,
inflammatory bowel disease, metastatic cancer, leukemia, Hodgkin’s
disease
BILIRUBIN
 Normally 0.3-1 mg/dl
 Collect in tiger top tube
 Increased: Liver damage, hemolysis, billary obstruction
ALKALINE PHOSPHATASE
 Normally 25-160 IU/L
 Collect in tiger top tube
 Increased: Liver disease, billary obstruction, bone tumors, healing
fracture, hyperparathyroidism, hyperthyroidism
 Decreased: Malnutrition, excessive vitamin D intake, pernicious
anemia, zinc deficiency
WHITE BLOOD COUNT
 Normally 4500-11,000
 Differential provides more clues to cause than overall count does
 Increased: Infection, inflammation, leukemia
 Decreased: Bone marrow failure, vitamin B12 deficiency
CAUSE OF INCREASED
DIFFERENTIALS
 Basophils: Leukemia, s/p spleenectomy
 Eosnophils: Allergies, asthma, parasites
 Lymphocytes: Viral infections, leukemia
 Monocytes: Bacterial infections, protozoan infections, ulcerative
colitis
 Neutophils: Bacterial infection, noninfectious tissue damage,
metabolic disorders
H & H
 Hematocrit: ~40-50% (lower in women, higher in men)
 The percentage of blood that is RBCs
 Decreased with anemia and blood loss
 Hemoglobin: ~12-16 g/dl (lower in women, higher in men)
 Does not acurately reflect acute bleeding because plasma and RBC
lost at same rate
COAGULATION STUDIES
 Collect in blue top tube
 PT: 11.5-13.5 second
 INR: 0.8-1.4
 Higher with mechanical heart valves or history of
thromboembolitic disease or atrial fibrillation
 INR is now the standard measure reported
CAUSES OF POSITIVE
VALUES ON UA
 Bilirubin: Jaundice, hepatitis, fecal contamination of sample
 Blood: Stones, BPH, infection, Foley cath
 Glucose: DM, pancreatitis, steroids
 Ketones: Starvation, high fat diet, diabetic ketoacidosis, vomiting,
diarrhea, asprin overdose
CAUSES OF POSITIVE
VALUES ON UA
 Leukoesterase: UTI
• Leukoesterase plus nitrates: 75% of UTI
• Neither LE or nitrates: 92% not UTI
 Protein: Renal failure, CHF