LABS

Question 1

URINALYSIS COLLECTION

Answer 1

50% midstream collection F contamination (>10 epithelial cells/HPF)

infection from catheterized specimen: 1-3%
20% if elderly or debilitated

Urine Dipstick basic U/A

Question 2

Urine Microscopy Cells

Answer 2

urinary sediment
Cells: white, red, squamous cells, others
Labs
Urgent care and ED only

Question 3

Leukocyte esterase

Answer 3

Enzyme produced by neutrophils
50% of pts with bacteriuria do not have pyuria
May be vaginal/penile contaminant, not diagnostic

Question 4

Nitrite

Answer 4

Gram negative bacteria convert nitrate to nitrite. E. Coli most common
UTI
Send urine for microscopic analysis, +/- culture

Question 5

RBC’s / heme

Answer 5

Rhabdomyolysis- myoglobin
lysed RBC
Free hemoglobin
intact Erythorocytes

Blood usually Cancer or menstral cycle

Question 6

Specific gravity

Answer 6

Concnetrated_Hydration, solutes

Question 7

Protein

Answer 7

Transietn common. Renal Fx

Seen w/ exercise

Question 8

Bilirubin

Answer 8

Liver FX

Question 9

Ketones

Answer 9

hydration/nutrition status, diabetes; product of ketone metabolism

Question 10

glucose

Answer 10

usually none. Present = renal tubules overwhelmed

>200 HIGH glucose if seen in urine

Question 11

Urine Microspy Cast

Answer 11

Fat laden histiocytes (oval fat bodies / macrophages) : nephrotic syndrome and proteinuria

Nephropathies or non-glomerular renal dz
Crystals

Casts – “active sediment” indicates renal disease
Erythrocyte casts = glomerular nephritis
Leukocyte casts = interstitial disease

Normal crysals- uric acicd, Ca, Phos
Abnorma- cholestrol, acylovir, sulfa

Question 12

Urine Microspy Crystals

Answer 12

Urate, phosphate, oxalate, cystine crystals: stone formers

Uric acid crystals: gout

Question 13

Urine Cultures

Answer 13

Obtained if infection unknown, at risk or “special” pt, sick patient

Collection method is key – females vs catheterization

Infection species significant/cause if >100K colony

2-3 days results

Treat all pts presumptively for gram neg infection; send cultures on all resistant/recurrent/”special” infections
Microscopy B4 culture

Question 14

Erythrocytes: RBC’s

Answer 14

Normal = 80-100
oxygen transport from lungs to tissues
protein: hemoglobin
survive 120d
Absolute number counted
MCV = Mean Corpuscular Volume 

Ht: Hgb 3:1 (if nt acute blood loss)

Question 15

Hematocrit

Answer 15

Males: 38-50%, Females 34-44% (kids age variable)

Percent of blood volume occupied by erythrocytes

Derived from (MCV and total RBC count)

Question 16

Hemoglobin

Answer 16

Males 14-18 g/dL
Females 12-16g/dL (pregnant 11-14g/dL, kids
Unique for its ability to carry and unload O2
defines anemia

Question 17

Blood Smears

Answer 17

not common-Information on red cell size, morphology, variation, hypochromia

cell types

% immature cells; i.e. bands, stabs

Presence of precursor cells usually restricted to marrow (blasts, nucleated erythrocytes)
Helpful for abn anemia, anemia not improving w/ tx, or Ht:Hgb ratio off

Question 18

Döhle bodies

Answer 18

are intra-cytoplasmic structures composed of agglutinated ribosomes;

inflammation and increased granulocytopoiesis
toxic neutrophils.

Question 19

Heinz bodies

Answer 19

inclusions within RBC’s composed of denatured hemoglobin .

hemolytic anemia

Question 20

Howell-Jolly bodies

Answer 20

are spherical blue-black inclusions of red blood cells seen on Wright-stained smears.

condensed DNA,

hemolytic anemias, dysfunctional spleens, splenectomy.

Question 21

Iron deficiency

Thalassemias

Hemolytic anemia

Lyme dz

Answer 21

Microcytic Anemia: MCV < 80

Question 22

Hemorrhage
Chronic disease
Bone marrow failure
Lead poisoning

Answer 22

Normocytic Anemia: MCV 80-100

Question 23

Vitamin B12 deficiency
Folate deficiency
Hypothyroidism
Hepatic failure

Answer 23

Macrocytic Anemia MCV > 100

Question 24

Leukocytes

Answer 24

4.5 – 11k
WBC counts and differential evaluate bacterial infection

Elevated neutrophil (PMN’s) count 
Inc. in the proportion of immature neutrophils (bands)= key sign of bacterial infection (left shift- more immature WBC seen)

Monitor w/ chemotherapy
RA, chronic inflam- 11-13K

Question 25

Platelet Count

Answer 25

Formation critical for effective hemostasis w/vessel injury 150-400 Thrombocytopenia < 100 < 50 severe bleeding from trauma < 10 spontaneous cerebral hemorrhage

Question 26

Chemistry Panels

Answer 26

electrolyte metabolism, fluid balance, acid-base status, renal function – from venous blood draw

Question 27

Na+

Answer 27

N-135 – 145 Holds water in extracellular fluid space Regulated by the kidneys in response to hormonal, neural, and vascular signals reflecting intravascular fluid volume hypo-osmolarity hyper-osmolarity

Question 28

Hypertonic Hyponatremia

Answer 28

Extracellular osmotic substance accumulates causing water to shift from intracellular to extracellular space lowering Na ``` correct the sugar 1st, sodium low bc glucose is high Every inc (100 mg/d)l in glucose above normal multiply by 1.6 to add the corrected mEq of Na. ``` Corrected sodium for the pt in head while correct sugar : 7 x 1.6 = 11.2 + 124 = 135 (normal total body sodium) Causes- hyperglycemia, mannitol (diuretic) Normal water excretion: low solute load in extracellular space from added water Hypotonic hypernatremia Psychogenic polydipsia – huge water intake Massive beer drinking (Potomania) Impaired water excretion – kidney issue Volume loss: diuretics, GI loss, bleeding Edematous states: cirrhosis, CHF Renal failure Cortisol deficiency: adrenal / hypopituitary: Severe hypothyroidism SIADH

Question 29

Hypernatremia

Answer 29

Dehydration – hypertonic hyperosmolar water loss :Fever, hyperthermia, diaphoresis, loss of thirst sensation, burns, hyperventilation Neurogenic diabetes insipidus- no antidiuretic hormone Nephrogenic diabetes insipidus- kidney dont respond to antidiuretic hormone Osmotic diuresis-glycosuria, mannitol, high protein intake

Question 30

K+

Answer 30

N 3.5 - 5.0 extracellular levels (6-7 no s/s lab handling, RBC lyis) intracellular ion exchange INC or DEC =life threatening electrolyte issue

Question 31

Chem 7

Answer 31

chemistry metabolic panel Basic | Na, K, BUN, Creatine, Glucose, CO2, HCO3

Question 32

Chem 12_16-20

Answer 32

Basic + LFTs (AST, ALT, PHos, bilirubin) Albumin, Ca

Question 33

CBC w. differential

Answer 33

Common, cheap CBC basic- Hg, Ht, RDW, MCV, MCH, WBC Diff: neutrophils, lymphocytes, basophils, eosinophils used when looking for particular infection.

Question 34

Hyperkalemia Levels > 6.0 myocardial irritability and fatal arrhythmias Common causes Renal failure Release of intracellular K+ into the extracellular space Metabolic acidosis, massive tissue breakdown, insulin deficiency

Answer 34

Inc. Potassium

Question 35

Potassium Abnormal? Think: Get an EKG!

Answer 35

Hyperkalemia Peaked T waves Widened PR and QRS intervals Flattening / loss of P waves ``` Hypokalemia U waves Flat or inverted T waves ST depression Decreased QRS voltage ```

Question 36

Low Potassium

Answer 36

Hypokalemia Question is-True body loss vs. shift to intracellular Decreased dietary intake/nutrition – alcoholics Diarrhea / vomiting Diuretics

Question 37

Chloride

Answer 37

N 98 – 109 mEq/l extracellular Major role as anion companion to Na + Changes in Cl – reflect changes in other extracellular ions* bicarb

Question 38

N 20-30 mEq/l major extracellular buffer disorders of the acid/base balance Serum CO2/HCO3 is ~5% higher then arterial bicarbonate (ABG – arterial blood gas) very sick if off

Answer 38

Bicarbonate

Question 39

Blood Urea Nitrogen

Answer 39

Normal 10 – 20 Urea = end product of protein metabolism related to -dietary protein, liver disease, tissue breakdown, dec renal blood flow, renal pathology 1/2 renal function lost before BUN or creatinine inc. Azotemia (early renal failure) = elevated BUN If dec. enough to cause a rise in BUN / creatinine then U/A will reveal proteinuria and abnormal urinary sediment Decreased renal blood flow = increased BUN BUN/creatinine ratio 10-15

Question 40

Creatinine

Answer 40

Normal 0.6 – 1.2 mg/dl #1 indicator of renal function End product of metabolism of creatine, Produced in liver, stored in muscle, phosphocreatine; storage for high energy phosphate Daily muscle cell metabolism= excretion of 1g creatinine/d Inc= loss of glomerular filtration 2x inc= indicates half of renal function Decision to begin dialysis Tx made on clinical symptoms rather than absolute #’s Chronic RF pts may tolerate creat > 20 mg/dl; Acute RF pt may not tolerate creat > 6

Question 41

Bilirubin- LFT

Answer 41

End product of heme metabolism breakdown of RBC’s conjugated in the liver and secreted into bile Increased conjugated (direct) 0.1-0.5 nml Liver dx. hepatic obstruction inc. level, w/ bilirubinuria) Increased unconjugated (indirect) 0.3-1.9 nml hemolysis or congenital defects in bilirubin transport (no associated bilirubinuria)

Question 42

LFT-ALT Alanine Tranferase

Answer 42

Hepatocyte enzyme Normal 3 – 35 Specific: elevation seen in pts with liver disease

Question 43

Normal 10 – 40 Enzyme present in large concentration in liver, heart, skeletal tissue Less specific than ALT for liver disease *Significant elevation in pts with massive hepatic necrosis, MI, Rhabdo

Answer 43

LFT Aspartate Aminotransferase (AST)

Question 44

LFT-ALT/AST

Answer 44

ALT and AST elevated in liver dz. ratio ALT : AST= > 1 alcoholic hepatitis and massive hepatic necrosis the ratio of ALT : AST =< 1

Question 45

N 25 – 100 Monophosphate concentrated in hepatocytes, bone, gut, lung Inc.= obstruction anywhere in the biliary tract pulmonary, renal, splenic infarction / inflammation, carcinoma

Answer 45

LFT- ALP Alkaline Phos

Question 46

LFT- Albumin

Answer 46

Normal 3.5 - 5.0 abundant protein in blood plasma; 40-60% of total protein “acid” ``` Dec : Primary liver disease Tissue damage / inflammation Malnutrition Malabsorption syndrome Renal failure ```

Question 47

Ca+ | ELEVATED

Answer 47

N- 8.5-10.5 ``` Hyperparathyroidism *Malignancy Thyrotoxicosis Vitamin D intoxication Sarcoidosis ```

Question 48

Renal disease Vitamin D deficiency Hypoparathyroidism Mg deficiency

Answer 48

Ca+ DECREASED

Question 49

Magnesium | INCREASED

Answer 49

Renal failure Iatrogenic ingestion Adrenal insufficiency

Question 50

Magnesium DECREASED

Answer 50

``` Decreased intake Diarrhea Alcoholism Hyperthyroidism SIADH (sydrome of inappro ADH) Some diuretics ```

Question 51

Imminent renal failure Hypoparathroidism Acromegaly Vitamin D intoxication

Answer 51

Phosphorous | INCREASED

Question 52

Phosphorous | DECREASE

Answer 52

``` Primary hyperparathyroidism Mg deficiency Vitamin D deficiency Alcoholism Soda Osteoporosis ```

Question 53

Creatinine kinase 38-120 ng/ml Myoglobin <85-90 Found in heart/skeletal muscle. Presence = damage Not specific. Used much less since advent of troponin

Answer 53

Cardiac Markers

Question 54

Troponin

Answer 54

``` nl <0.01 – 0.03 ng/mL (Lab/method dependent) #1 Gold Standard for cardiac ischemia ``` cardiac protein controls calcium mediated interaction of actin/myosin; Inc= degradation of actin and myosin filaments in the area of myocardial damage. “Trop leak” Rises 4-6 hours after MI At least two serial serum levels 6 hours apart are required to r/o acute MI in pt’s w/ acute CP If last episode of CP >6hrs prior – single troponin acceptable elevated for as long as 10 days after myocardial injury.

Question 55

BNP | Brain Natriuretic Peptide

Answer 55

Normal: <100pg/ml response to left ventricular stretching and increased wall tension predict prognosis/death in heart failure in Pts w/ sx Not a screening test High negative predictive value = if test is negative, rules out heart failure better than a positive test predicts it affect this test: HTN drugs, exercise, etc Useful and expensive (>$200)

Question 56

Lipid Panel

Answer 56

Total cholesterol, HDL, TGS LDL calculated (not good lipids, indirectly) TC <200 HDL >35 TG< 150 (while fasting) > 400 inaccurate LDL LDL depends on CV Finger prick or Lab

Question 57

lactic Acid

Answer 57

N < 2.0 2.0-3.9- consider sepsis >4.0 sepsis * Gold stardard for use of TX w/ severe infection Shock/sepsis= anerobic, O2 delivery inadequate. By product Lactic acidosis=hypoeffusion, hypoxia Not routine test- IN Pt or ED

Question 58

PT Prothrombine Time

Answer 58

N 10-13s injured vessles release thromboplasin, activates exrinisit pathways for coagulation Assess for anticoag TX Vit K deficiency

Question 59

INR international normalized Ratio

Answer 59

``` N 0.5-1.2 If anticoag drugs 2-3.5 #1 monitor for anticoag TX INT= Pts PT/control PT Warfarin ordered w/ PT ```

Question 60

Ammonia

Answer 60

N 30-70 ug/dl ``` Indicates hepatic parenchymal damage Liver dz Asterixis- hepatic encephalopathy (can't convert NH3 to urea, damages CNS) Cirrohis Alcholics Not routin LFT ```