Labs & Imaging Review

A set of 45 vocabulary flashcards covering laboratory reference ranges, interpretations, and imaging findings from the review notes.

Sodium (Na)

A serum electrolyte with a reference range of $135-145\,mmol/L$; it is decreased by ADH excess, and increased due to retention or water loss.

Potassium (K)

An electrolyte with a reference range of $3.5-4.5\,mmol/L$; deficiency occurs in alkalosis, while excess is seen in acidosis and tissue breakdown.

Chloride (Cl)

A serum electrolyte with a reference range of $96-106\,mmol/L$; increased levels are associated with dehydration, respiratory alkalosis, or kidney disease.

Bicarbonate (total carbon dioxide)

Also known as $HCO_3$, it has a reference range of $22-29\,mmol/L$; decreased levels indicate metabolic acidosis or compensation for respiratory alkalosis.

Anion gap

Calculated as $(Na + K) - (Cl + HCO_3)$ with a reference range of $12-20\,mmol/L$; an increase indicates the presence of an unusual acid, such as in diabetes mellitus.

Hemoglobin

A hematology measure with reference ranges of $130-175\,g/L$ for men and $120-160\,g/L$ for women; increased in Polycythemeia rubra vera.

Hematocrit

Also known as packed cell volume, it has reference ranges of $0.40-0.52\,L/L$ for men and $0.37-0.48\,L/L$ for women.

Mean cell volume

A measure of red blood cell size with a reference range of $86-98\,fL$; it is decreased in iron deficiency and increased in vitamin $B_{12}$ or folate deficiency.

White cell count

A hematology test with a reference range of $4.5-10.5 \times 10^9/L$; decreased in aplastic anaemia and increased in infections or inflammation.

CD4 cells

These are T helper lymphocytes used in the assessment of HIV; their number is decreased in AIDS.

CD8 cells

These are T-suppressor cells.

Prothrombin time (PT)

A blood coagulation test with a range of $9-12$ seconds that may be reported as INR; increased in liver disease or vitamin K deficiency.

Activated partial thromboplastin time APTP (PTT)

A coagulation test with a reference range of $< 35$ seconds; increased in deficiencies of factors VIII, IX, X, XI, or XII.

D-dimer

A test with a reference range of $< 250\,mcg/L$ used to assess for DIC, DVT, PE, pregnancy, and cancer.

Universal donor

Refers to blood type O.

Universal recipient

Refers to blood type AB.

Erythropoietin

The hormone which induces erythrocyte production and release.

Ferritin

A stored form of iron with reference ranges of $12-300\,ug/L$ for men and $12-150\,ug/L$ for women; it acts as an acute phase reactant.

Transferrin

The protein responsible for carrying iron (Fe) in the blood.

Haptoglobin

A heme scavenger protein.

Cholesterol

A lipid measured to assess heart disease risk; healthy levels are generally $< 5.2\,mmol/L$.

Triglyceride

A lipid with a reference range of $< 1.7\,mmol/L$; increased levels are associated with heart disease risk, alcoholic liver, and pancreatitis.

Aspartate aminotransferase (AST)

An enzyme with a reference range of $9-40\,IU/L$; increased in conditions affecting the liver, heart, muscle, and in acute pancreatitis.

Alkaline phosphatase (ALP)

An enzyme with a reference range of $30-120\,IU/L$; increased in cholestasis, bone disease, bone growth, and cancers.

Creatinine clearance

A urinalysis measure with a reference range of $0.8-1.3\,mL/s$; decreased in kidney failure and shock.

Specific gravity

A dipstick urinalysis measure with a random sample range of $1.015-1.025$; concentrating ability is lost in kidney issues.

Parathyroid hormone (PTH)

A hormone with a reference range of $0-130\,pmol/L$; increased in kidney disease and hyperparathyroidism.

Troponins T or I

Markers used to predict heart disease risk or detect myocardial infarction; high sensitivity tests can detect heart attacks in $2-3$ hours.

Natriuretic peptide A or B type

A marker for congestive heart failure; BNP reference range is $< 100\,ng/L$.

Alanine aminotransferase (ALT)

A liver function enzyme with a reference range of $10-40\,IU/L$; increased in hepatitis.

Digoxin therapeutic range

The preferred blood concentration for heart failure management is $0.5-0.9\,ng/mL$.

Alpha foetoprotein (AFP)

A cancer marker with a reference range of $< 40\,mg/L$; used in the diagnosis of liver cancer, Down syndrome, and spina bifida.

CA 125

A cancer marker used in the diagnosis and monitoring of ovarian and endometrial cancer.

CA 15.3

A cancer marker with a reference range of $< 22\,kU/L$ used for breast cancer.

CA 19.9

A cancer marker with a reference range of $< 37\,kU/L$ used for pancreatic cancer.

Carcinoembryonic antigen CEA

A cancer marker with a reference range of $< 3\,mcg/L$ ($< 5\,mcg/L$ for smokers) used for colon cancer and other gut cancers.

Radioallergosorbent test (RAST)

A specific IgE test used to identify allergens like cows’ milk, egg, peanut, wheat, and shellfish.

Glycated hemoglobin

Used to monitor chronic diabetes, with a reference range of $0.02-0.05$.

DEXA Scan

The gold standard imaging method for bone density assessment and osteoporosis diagnosis.

Bamboo Spine

An imaging finding on X-ray or MRI characteristic of Ankylosing Spondylitis.

Lead Pipe Colon

An imaging finding on barium enema or colonoscopy in Ulcerative Colitis (UC) caused by the loss of haustral folds.

String Sign

An imaging finding in Crohn's Disease indicating the narrowing of the terminal ileum.

Apple Core Lesion

An imaging finding on colonoscopy or CT colonography indicating colon cancer.

Lens-Shaped Hemorrhage

An imaging finding on a CT scan characteristic of an Epidural Hematoma.

Crescent-Shaped Hemorrhage

An imaging finding on a CT scan characteristic of a Subdural Hematoma.