Lemar MT Baby Notes (Clinical Chemistry)

Conversion factor of bilirubin, mg/dl to umol/L

17.1

CF of creatinine, mg/dL to umol/L

88.4

CF of Na+, K+, Cl-, mEq/L to mmol/L

1

CF of TP/albumin/globulin, g/dL to g/L

10

CF of Ig from mg/dL to mg/L

10

CF of Ig from mg/dL to g/L

0.01

CF of thyroxine, ug/dL to nmol/L

12.9

CF of BUN from mg/dL to mmol/L

0.357

CF of BUN to urea

2.14

CF of urea to BUN

0.467

Normal BUN:Creatinine ratio

10-20:1

Indirect method used to assess glomerular filtration functioning capabilities of the kidneys

Creatinine clearance

Index of overall renal function

Creatinine

Appears in the urine when reabsorption is incomplete because of proximal tubular damage, as in AKI

B2-microglobulin

Assay for urea that is inexpensive but lacks specificity

Colorimetric, diacetyl

Assay for urea that measures ammonia formation

Enzymatic

Simple non-specific method for creatinine

Colorimetric, endpoint

Assay for creatinine which is rapid and with increased specificity

Colorimetric: kinetic

Assay for creatinine that measures ammonia colorimetrically or with ISE

Enzymatic

Assay for uric acid, problems with turbidity

Colorimetric

Assay for uric acid that needs special instrumentation and optical cells

Enzymatic: UV

Assay for uric acid, interference by reducing substances

Enzymatic: H2O2

A progressive and irreversible loss of renal function, results from several disease entities.

Chronic renal failure

Anticoagulant with least interference with analysis

Heparin

Heparin for most chemistry tests

Lithium heparin

Glucose is metabolized at what rate in room temperature:

7 mg/dL/hr

Glucose is metabolized at what rate at 4C:

2 mg/dL/hr

Blood glucose levels of less than 50 mg/dL

Hypoglycemia

Patient is ambulatory; fasting of 8-14 hours

Unrestricted diet of 150 grams of CHO for 3 days prior to testing

OGTT

Performed routinely to monitor glucose control

Glycosylated hemoglobin

Gestational diabetes patients develop DM within:

5 to 10 years

Sodium concentration in patient with DM (increased, decreased, or normal)

Decreased - due to polyuria

NCEP guidelines for acceptable measurement error:

Cholesterol: ?

LDL, HDLc: ?

Triglycerides: ?

NCEP guidelines for acceptable measurement error:

Cholesterol: CV

Minor lipoproteins

IDL and Lp(a)

Major structural protein in HDL

Apo-A1

Major structural protein in VLDL and LDL

Apo-B100

Structural protein in CM

Apo-B48

LDL-c may be calculated form measurements of:

TC, TAG, and HDL-c

Floating beta lipoprotein

B-VLDL

Sinking pre-beta lipoprotein

Lp(a)

HDL-c concentration protective against heart disease

>/= 60mg/dL

HDL-c concentration major risk for heart disease

<40 mg/dL

Given the serum cholesterol concentration, give the age range related:

Legend: MR (moderate risk), HR (high risk)

1. MR: >170 mg/dL, HR: >185 mg/dL

2. MR: >240 mg/dL, HR: >260 mg/dL

1. 2-19 years old

2. 40 and over

Given the serum cholesterol concentration, give the age range related:

Legend: MR (moderate risk), HR (high risk)

1. MR: >220 mg/dL, HR: >240 mg/dL

2. MR: >200 mg/dL, HR: >220 mg/dL

1. 30-39 years old

2. 20-29 years old

One-step, direct method for cholesterol

Liebermann-Burchardt

Old reference method for cholesterol

Abell-Kendall method

Current CDC recommended method/reference method for cholesterol

GC-MS

Counterion of Na+

Cl-

Counterbalance of Na+

Cl-

Routinely measured electrolytes

Na+, K+, Cl-, and HCO3-

Largest contribution to the osmolality value of serum

Na+, Cl-, and HCO3-

Formula to get the osmolality of plasma:

2(Na) + glucose/20 + BUN/3, or;

1.86(Na) + (glucose/18) + (BUN/2.8) + 9

Indirectly indicates the presence of osmotically active substances other than Na+, urea, or glucose, such as ethanol, methanol, ethylene glycol, lactate, or B-hydroxybutyrate

Osmolal gap

Differenc between the measured osmolality and the calculated osmolality

Osmolal gap

Formula to get the anion gap (NV: 7-16 mmol/L)

Na - (Cl + HCO3)

Formula to get the anion gap (NV: 10-20 mmol/L)

(Na + K) - (Cl + HCO3)

Indication of increased concentrations of the unmeasured anions

Anion gap >16 mmol/L

Can also result from ketotic states, lactic acidosis, salicylate and methanol ingestion, uremia, or increased plasma proteins

Increased anion gaps

Either an increase in unmeasured cations or a decrease in the unmeasured anions

Decreased anion gaps of <10 mmol/L

The ___ is also useful as a quality control measure for electrolyte results.

anion gap

HYPERNATREMIA DUE TO:

EXCESS WATER LOSS - DiRe ProProSe

DiRe ProProSe

Di - Diabetes insipidus

Re - Renal tubular disorder

Pro - Prolonged diarrhea

Pro - Profuse sweating

Se - Severe burns

HYPERNATREMIA DUE TO:

DECREASED WATER INTAKE: In MentOl

In MentOl

In - Infants

Ment - Mental impairment

Ol - Older persons

HYPERNATREMIA DUE TO:

INCREASED SODIUM INTAKE OR RETENTION: HypeSoDi

HypeSoDi

Hype - Hyperaldosteronism

So - Sodium bicarbonate excess

Di - Dialysis fluid excess

HYPONATREMIA DUE TO:

INCREASED SODIUM LOSS: HyPo! Di Ka SPS?

HyPo! Di K(a) SPS?

Hy - Hypoadrenalism

Po - Potassium deficiency

Di - Diuretic use

K(a) - Ketonuria

S - Salt-losing nephropathy

P - Prolonged vomiting or diarrhea

S - Severe burns

HYPONATREMIA DUE TO:

INCREASED WATER RETENTION: ReNCH

ReNCH

Re - Renal failure

N - Nephrotic syndrome

C - Congestive heart failure

H - Hepatic cirrhosis

HYPONATREMIA DUE TO:

WATER IMBALANCE: Ps. SEx

Ps. SEx

Ps - Pseudohyponatremia

S - SIADH

Ex - Excess water intake

HORMONAL REGULATION OF CALCIUM:

Enhance resorption from bone, stimulate vitamin D synthesis, enhance tubular reabsorption

Parathyroid hormone

HORMONAL REGULATION OF CALCIUM:

Stimulate calcium uptake by bone, decrease renal tubular reabsorption

Calcitonin

HORMONAL REGULATION OF CALCIUM:

Enhance intestinal absorption, enhance resorption from bone, increase renal tubular reabsorption

Vitamin D metabolites

ACID-BASE DISTURBANCE:

Excess CO2 accumulation

Respiratory acidosis

ACID-BASE DISTURBANCE:

Excess CO2 loss

Respiratory alkalosis

ACID-BASE DISTURBANCE:

Excess H+ production

Metabolic acidosis

ACID-BASE DISTURBANCE:

Excess H+ loss or excess alkali intake

Metabolic acidosis

Fever will ___ (increase, decrease) pO2 by ___:

decrease, 7%

Fever will ___ (increase, decrease) pCO2 by ___:

increase, 3%

Uses potentiometry

pH, pCO2

Uses amperometry

pO2

89-90% of all CO2 in serum is in what form?

HCO3-

Driving force of the bicarbonate buffer system

CO2

The shape of the key (substrate) must fit into the lock (enzyme)

Lock and Key (Emil Fischer)

Substrate binding to the active site of the enzyme

Induced-fit model (Daniel Koshland)

Reactants are combined; reaction proceeds for a designated time; reaction is stopped and a measurement is made

Fixed-time

Multiple measurements of absorbance are made during the reaction; more advantageous

Continuous monitoring/kinetic

Forward reaction for CK

Tanzer-Gilvarg

Reverse reaction for CK

Oliver-Rosalki

Forward reaction of LD

Wacker

Reverse reaction for LD

Wrobleuski and LaDue

Enzyme with high specificity for RBCs, prostate

ACP

Enzyme with high specificity for the liver

ALT

Enzyme with high specificity for the pancreas

LPS

Enzyme with high specificity for pancreas, salivary gland

AMS

Enzyme with MODERATE specificity for liver, heart, and skeletal muscles

AST

Enzyme with MODERATE specificity for heart, skeletal muscles, and brain

CK

Enzyme with LOW specificity for liver, bone, and kidney

ALP

Enzyme with LOW specificity for all tissues

LDH

Most potent of the estrogens

Estradiol

Hypersecretion of GH in adults

Acromegaly

Confirmatory test for acromegaly

OGTT

Effect of GH to blood glucose

Increase

Increase in cortisol caused by excessive development and activity of pituitary gland

Cushing's disease