lab med test 2 lecture 9 and 10

very low TSH

hight T4

high T3

pt with clinical hyperthyriodism levels will look like

weight loss

tachycardia

tremor

heat tolerance

what are symptoms for hyperthyroidism

- unconjugated

- fat soluble

- bound to albumin to travel to liver

indirect bilirubin

- conjugated

- water soluble

- stored as bile in gallbladder or excreted in feces or urine

direct bilirubin

- abdomnal pain

- nausea

- vomitting

- peripheral edema

Why would we check the liver function based off gi

fatigue

Why would we check the liver function based off general apperance

- generalized pruritic

- jaundice

Why would we check the liver function based off skin

scleral icterus

Why would we check the liver function based off eyes

dark colored

Why would we check the liver function based off urine

- routine screening for liver infections or inflammation

- monitoring for cirrhosis and hepatitis

- monitoring effects for medication

Why would we check the liver function in normal visits

indirect bilirubinemia

stems from hepatocellular dysfunction inability to convert from unconjugated to conjugated bilirubin in the liver

direct bilirubinemia

obstruction of bile duct with gallstone or tumors (cholestasis) inability to be excreted properly

hepatic function panel over CMP

what do you use to differentiate the cause of hyperbilirubinemia

shows protiens that help maintain osmotic pressure within vascular space

why is albumin, globulin, and A/G ratio important

albumin

what is synthesized in the liver and maintains osmotic pressure

albumin

measures of hepatic function and nutrition

globulin

synthesized in the liver

carrier protein, complement, enzymes, and immunoglobin

some measure nutirtion

metabolism of drugs

what does metabolism in the liver do

A/G ration

can differentiate between GI protein loss, liver disease and autoimmune disease

PT/INR

reflects synthetic function

bilirubin

total= indirect + direct

metabolism and excresion

- albumin

- PT/INR

- Bilirubin

what are the markers of hepatic function

Alkaline Phosphatase (ALP)

what is an enzyme found mostly in the liver, bilary tract epithelium and bone that is useful in detecting liver and bone disease

Alkaline Phosphatase (ALP)

what is the most sensitive test for tumor metastasis to liver

intra/extra hepatic obstruction of biliary disease, cirrhosis

what causes greater elevation in Alkaline Phosphatase (ALP)

hepatic tumors, hepatotoxic drugs, hepatitis

what causes smaller elevations in Alkaline Phosphatase (ALP)

PT and albumin

when looking for synthetic function of the liver what do you look at

Alanine aminotransferase (ALT)

enzyme that is found predominately in the liver with smaller amounts in the kidney, heart, and skeletal muscle

liver injury or dysfuntion

specific for hepatocellular disease

what causes elevation in Alanine aminotransferase (ALT)

acetaminophen, allopurinol, codeine, indomethacin, OCP, salicylates, tetracyclines, amongst others

what drugs affect alanine aminotransferase (ALT)

Aspartate aminotransferase (AST)

enzyme found highly concentrated in the liver, heart, and skeletal muscles

acute hepatitis 20 times normal

gallstone obstrution 10 times normal

cirrhosis- ast equal amounts of active inflammation

what causes elevations in Aspartate aminotransferase (AST)

increased ALT/AST> ALP

how is hepatic injury shown

ALT

what is more specific to the liver

AST

how does most hepatocellular injury show

>2.1

how does alcoholic fatty liver disease affect your AST:ALT

drugs induced liver injury

chronic viral hepatitis

nonalcohol fatty liver disease

what causes a AST:ALT to be less than 1

alcohol fatty liver disease

nonalcoholic fatty liver disease

wilsons dsiease

cirrhosis

what causes a AST:ALT to be greater than 1

↑↑ALP > ALT/AST

what does cholestais do to ALP, ALT and AST

- Alkaline Phosphatase (ALP)

- Gamma-glutamyl transferase (GGT), Confirm hepatic source of ALP

- Direct (conjugated) bilirubin

what elevates your cholestasis

Gamma-glutamyl transferase (GGT)

High concentrations in liver and biliary tract and Very sensitive in detecting biliary disease (i.e.

cholecystitis, biliary obstruction)

Gamma-glutamyl transferase (GGT)

Can detect chronic alcohol ingestion

- GGT usually parallels ALP

- ↑ ALP with normal GGT = skeletal disease

- ↑ ALP with ↑ GGT = hepatobiliary disease

what elevates Gamma-glutamyl transferase (GGT)

lipase

what is the best things to test for pancreatic enzymes

triiodothyronine (T3) and

thyroxine (T4)

what does the thyroid gland produce

subclinical hyperthyroidism

A 65 y/o male with a history of hypertension, presents to his PCP for a routine follow-up. He

takes lisinopril and a daily multivitamin. His blood pressure is well controlled today. You check

his thyroid function and find the following after repeating the labs.

TSH - 0.22 uIU/mL (low)

Free T4 - 1.53 ng/dL (normal)

T3 - 150 ng/dL (normal)

subclinical hypothyroidism

A 65 y/o male with a history of hypertension, presents to his PCP complaining of increased

fatigue, insomnia and depressed mood. He takes lisinopril and a daily multivitamin. His blood

pressure is well controlled today. You check his thyroid function and find the following after

repeating the labs.

TSH - 6.5 uIU/mL (high)

Free T4 - 1.53 ng/dL (normal)

clinical

Symptoms present, labs abnormal

subclinical

No symptoms, only labs abnormal

T3 and T4

what hormones does the thyroid gland produce

TSH

what is the first test to order if you are suspicious of thyroid disease

Hashimoto's thyroiditis

Anti-TPO Antibodies associated disease

Hashimoto's thyroiditis

Anti-thyroglobulin Antibodies disease associated

- hypothyroidism

- hyperthyroidism

what conditions can the TSH diagnose

morning

when is the best time to order a TSH

STOP biotin for 48 hours and repeat TSH

along with free T4 and T3 in the AM

A 39 y/o female presents to her PCP for an annual physical. She has no known PMH and

takes a daily multivitamin along with a 10 mg biotin supplement for her hair and nails.

Her ROS is positive for an unexplained 10 lbs weight loss over 3 months and mild

intermittent palpitations.

Vitals: BP 135/89, P 95 bpm, BMI 22, T 98.9F, SpO2% 99%, RR 11.

Physical Exam: unremarkable

You perform the following labs: CBC, CMP, lipids, TSH, UA.

TSH 0.2 (low)

What do you tell the pt next

T3

what affects metabolism, used to diagnose and monitor hyperthyroidism

Free and metabolically active

what is T4 that is not bound to proteins

hyperthyroidism

Graves' disease is an autoimmune disorder and the most common cause of

Thyroid Stimulating Immunoglobulins

TSI

Thyroid receptor antibodies

TRAb

- bradycardia

- tachycardia

- goiter

what would your physical exam look like for a thyorid function screening

- pregnancy

- elderly

- autoimmune disease

who is high risk for thyroid disease

- weight gain

- cold

- goiter

- bradycardia

hypothyroidism symptoms

- weight loss

- tachycardia

- hot

hyperthyroidism symptoms

T3 and T4

Antibodies directed against the thyroid to stimulate production

- TSI

- TRAb

- T3

-T4

what is used support the diagnosis of graves

Hashimoto's

TPO elevated in more than 90% of patients with

Hashimotos

what is the most common primary hypothyroididm in iodine rich countries

Because patient's bloodwork was completed in the afternoon and you know that thyroid concentrations are diurnal, you repeat the TSH test along with free T4 test in the morning.

A 42 y/o Asian female presents to her PCP for an annual physical around3 pm. No relevant past medical history and takes no medications or supplements.

Her ROS and physical examination are both unremarkable.

Vitals: BP 103/70, P 67 bpm, BMI 24, T 98.6F, SpO2% 99%, RR 11.

You perform the following labs: CBC, CMP, lipids, TSH, UA.

TSH 6.0 (high)

what is you next steps

hypothyroidism

A 42 y/o Asian female presents to her PCP for an annual physical around3 pm. No relevant past medical history and takes no medications or supplements.

Her ROS and physical examination are both unremarkable.

Vitals: BP 103/70, P 67 bpm, BMI 24, T 98.6F, SpO2% 99%, RR 11.

You perform the following labs: CBC, CMP, lipids, TSH, UA.

TSH 6.3 (high)

T4 0.34 (low)

Hyperthyroidism

what would be the diagnosis of high free T4

- fatigue

- constipation/diarrhea

- depression/anxiety

- heat intolerance/ cold intolerance

- hair thinning

- weight loss/ weight gain

what are the most common symptoms for thyroid disease

hypothyroidism

what would be the diagnosis of low free T4

hyperthyroidism

TSH 0.29 (low)

T4 4.12 (high)

biotin supplements

what do you want to advice patients to stop taking 48 hours before getting thyroid labs

repeat it to confirm

what should you do if your TSH is abnormal

non-thyroidal illness, medications, pregnancy

what can effect thyroid diseases

Graves' disease

TSI (TSH receptor antibodies) disease associated

T3 and T4

what does the anterior pituitary gland stimulate the thyroid gland to release

anterior pituitary gland

what is TSH secreted by

subclinical hypothyroidism

TSH elevated, Free T4 normal, Common in elderly, May progress to overt hypothyroidism

subclinical hyperthyroidism

TSH low, Free T4 and Free T3, risk: atrial fibrillation, osteoporosis