Pharm Foundations: Labs/Monitoring

Question 1

Agranulocytosis Definition/Drug Causes

Answer 1

• Decrease in granulocytes (WBC that secrete granules) including neutrophils, basophils, and eosinophils
• Drug Causes: Clozapine, propylthiouracil, methimazole, procainamide, carbamazepine, SMZ/TMP, isoniazid

Question 2

Calcium

Answer 2

• Corrected calcium if albumin is low
• Increased Ca: vitamin D, thiazide diuretics
• Decreased Ca: long-term heparin, loop diuretics, bisphosphonates, cinacalcet

Question 3

Magnesium

Answer 3

-Decreased due to PPIs and diuretics

Question 4

Phosphate

Answer 4

Increased in renal failure

Question 5

Potassium

Answer 5

• Increased: ACE-I, ARBs, aldosterone receptor antagonists, canagliflozin, cyclosporine, tacrolimus, K+ supplements, SMZ/TMP, drospirenone OC
• Decreased: Beta-2 agonists, diuretics, insulin

Question 6

Sodium

Answer 6

-Decreased: carbamazepine, oxcarbazepine, SSRIs, diuretics

Question 7

Bicarbonate

Answer 7

-Decresed due to topiramate

Question 8

BUN

Answer 8

-Increased from renal impairment and dehydration

Question 9

SCr

Answer 9

• Increased from drugs that impair renal function
• Includes: aminoglycosides, amphotericin B. cisplatin, colistimethate, cyclosporine, loop diuretics, polymixin, NSAIDs, radiocontrast dye, tacrolimus, vanco

Question 10

Anion Gap

Answer 10

-Increased anion gap suggests metabolic acidosis

Question 11

WBC

Answer 11

• Increased by systemic steroids

- Decreased by clozapine and carbamazepine

Question 12

Neutrophils

Answer 12

• Also called polymorphonuclear cells (PMNs) and segmented neutrophils (segs)
• Bands are immature neutrophils released from bone marrow to fight infection (“left shift”)

Question 13

Eosinophils

Answer 13

-Increased by asthma, inflammation, parasitic infection

Question 14

Basophils

Answer 14

-Increased from hypersensitivity reaction

Question 15

Lymphocytes

Answer 15

• Increase by viral infection and lymphoma

- Decreased from bone marrow suppression, HIV, or systemic steroids

Question 16

RBCs

Answer 16

• Increased from erythropoiesis-stimulating agents (ESAs)
• Decreased from chemotherapy agents that target bone marrow, deficiency anemias (B12/folate), hemolytic anemias, and sickle cell anemia

Question 17

Hemoglobin (Hgb)

Answer 17

• Increased from ESAs

- Decreased in anemias and bleeding

Question 18

MCV

Answer 18

• Increased from B12 and folate deficiencies

- Decreased from iron deficiency

Question 19

Folic Acid

Answer 19

• Folic acid and B12 are examined for macrocytic anemia
• Decreased from phenytoin/fosphenytoin, primidone, methotrexate, SMZ/TMP
• Supplement folate in childbearing aged women

Question 20

Vitamin B12

Answer 20

-Decreased from PPIs and metformin

Question 21

Reticulocyte Count

Answer 21

-Decreased from untreated anemia (either type) and bone marrow suppression

Question 22

Coombs Test, Direct

Answer 22

• AKA: DAT
• Used to diagnose hemolytic anemia
• Drug Causes: penicillins/cephalosporins (prolonged use/[high]), dapson, isoniazid, levodopa, methyldopa, methylene blue, nitrofurantoin, pegloticase, primaquine, quinidine, quinine, rasburicase, rifampin, and sulfonamides
• Discontinue offending drug if hemolytic anemia is suspected

Question 23

G6PD

Answer 23

• Hemolytic anemia due to G6PD deficiency
• Stress and food like fava beans
• Drug Causes: Dapsone, methylene blue, nitrofurantoin, pegloticase, primaquine, rasburicase, sulfonamides

Question 24

Anti-Xa

Answer 24

• Used to monitor LMWH and UFH
• Recommend to monitor in pregnancy
• Increased from heparin and LMWHs

Question 25

PT/INR

Answer 25

- Used to monitor warfarin - Increased INR from warfarin and liver disease - False increases to INR from daptomycin, oritavancin, and telvancin

Question 26

aPTT/PTT

Answer 26

- Used to monitor UFH | - Falsely elevated from oritavancin and telavancin

Question 27

PLTs

Answer 27

-Decreased from heparin, LMWH, fondaparinux, linezolid, and valproic acid

Question 28

ELISA/SRA

Answer 28

- Used to test for heparin-induced platelet antibodies - ELISA = first test - SRAs = confirmatory

Question 29

Highly Protein-Bound Drugs

Answer 29

- Warfarin, calcium, valproic acid, and phenytoin | - Require serum concentration correction for low albumin

Question 30

AST/ALT

Answer 30

- Used to monitor liver function | - Increased from injured hepatocytes

Question 31

Bilirubin

Answer 31

-Increased by liver damage or blocked bile duct

Question 32

Ammonia

Answer 32

- Not diagnostic, but often monitored for hepatic encephalopathy - Increased by valproic acid and topiramate - Decreased by lactulose

Question 33

Amylase/Lipase

Answer 33

- Increased in pancreatitis | - Drug causes: didanosine, GLP-1 agonists, DPP4-i, valproic acid, and hypertriglyceridemia

Question 34

CK/CPK

Answer 34

- Creatinine kinase or creatinine phosphokinase - Used to assess muscle inflammation and damage - Increased: daptomycin, statins, tenofovir, raltegravir, and dolutegravir

Question 35

Troponin/B-Type Natiuretic Peptide

Answer 35

- TnT, TnI, BNP - Used to diagnosis MI and are markers of cardiac stress - Higher values indicate increased likelihood of heart failure when consistent with symptoms

Question 36

Lipid Panel

Answer 36

- Fasting to begin 9-12 hours before draw - Non-HDL = TC - HDL - LDL < 100 - HDL > 60 (desirable), < 40 (low in males) - Non-HDL < 130 - TG < 150

Question 37

CRP

Answer 37

- C-reactive protein - 0-0.5 - Elevated levels suggests inflammation

Question 38

FPG

Answer 38

- >126 consistent with diabetes - 100-125 is pre-diabetes - <100 is preferable - Fasting at least 8 hours

Question 39

A1C

Answer 39

- <7% per ADA | - Average blood glucose over past 3 months

Question 40

C-peptide

Answer 40

- Used to distinguish DMI and II | - Decreased or absent in DMI (insulin breakdown product)

Question 41

TSH

Answer 41

- Increased TSH = hypothyroidism, Decreased TSH = hyperthyroidism - Levels can be affected by amiodarone and interferons - Increased (hypothyroidism) due to tyrosine kinase inhibitors, lithium, and carbamazepine

Question 42

Uric Acid

Answer 42

- Used to diagnose/treat gout - Increased from diuretics, niacin, low dose aspirin, pyrazinamide, cyclosporine, tacrolimus, select chemotherapy and pancreatic enzyme products

Question 43

Autoimmune tests

Answer 43

- CRP - RF (rheumatoid factor) - ESR (erythrocyte sedimentation rate) - ANA (antinuclear antibodies)

Question 44

DILE

Answer 44

- Drug-induced lupus erythematosus - Drug Causes: anti-TNF agents, hydralazine, isoniazid, methimazole, methyldopa, minocycline, procainamide, propylthiouracil, quinidine, terbinafine - Discontinue causative agents if DILE suspected

Question 45

Lactic Acid

Answer 45

-Increased by metformin and NRTIs (HIV drugs)

Question 46

Prolactin

Answer 46

-Increased with haloperidol, risperidone, and paliperidone

Question 47

PPD

Answer 47

- Purified Protein Derivative or Mantoux test | - TB skin test

Question 48

RPR

Answer 48

- Rapid plasma reagin | - Syphilis antibody test

Question 49

TPMT

Answer 49

- Thiopurine methyltransferase | - Deficiencies place patients at higher risk of myelosuppression if using azathioprine and mercaptopurine