DDX LAB VALUES

Question 1

Hematocrit

Answer 1

38-54% men, 36%-47% Women

High values
High-altitude areas, chronic smoker, dehy- dration (false positive), polycythemia vera, eryth- ropoietin (Epogen)

Low Values
Anemia, blood loss, nutritional deficiency (iron, vitamin B12, and folate), chemotherapy, cancer
(bone marrow), kidney failure

Question 2

Hemoglobin

Answer 2

14–18g/dl (men) (Hb)
12–16 g/dl (women)
12–14 g/dl (children)
14.5–24.5 g/dl (newborns)

High Values
High-altitude areas, dehydration (false positive), chronic smoker, polycythemia vera, emphysema, erythropoietin (Epogen)

Low Values
Loss of blood (injury, surgery, ulcers, and cancer); chemo- therapy; iron, vitamin B12, or folate deficiency; thalassemia; sickle cell anemia; bone marrow complications

Question 3

Erythrocytes (RBCs)

Answer 3

4. 5–6 × 104 (men)
5. 3–5.5 × 104 (women)

High Values
Dehydration, polycythemia vera, kidney cancer, kidney transplant, heart failure, chronic obstruc- tive pulmonary disease (COPD), congenital heart disease, carbon monoxide poisoning, sleep apnea

Low Values
Anemia; bone marrow com- plications; bleeding; multiple myeloma; copper, folate, and vitamin B6 and B12 deficiency; leukemia; pregnancy; RBC destruction

Question 4

Reticulocytes

Answer 4

0–1% of RBCs

High Values
Kidney disease producing erythropoietin, hemolytic anemia, erythroblastosis fettles

Low Values
Bone marrow failure; liver dis- ease (cirrhosis); vitamin B12, iron, or folate deficiency; kidney disease; radiation therapy

Question 5

Leukocytes, total

Answer 5

5,000–10,000 cells/ mm3

High Values
Bacterial infection, smoking, inflammatory diseases (e.g., rheumatoid arthritis), leukemia, tissue damage, some drugs (e.g., albuterol, lithium, and corticosteroids)

Low Values
Some drugs (e.g., chemother- apeutics, clozapine, antibiotics, and diuretics), bone marrow problems, autoimmune diseases (e.g., systemic lupus erythema- tosus), liver or spleen disease, radiotherapy, viral infections

Question 6

Mean cor- puscular vol- ume (MCV)

Answer 6

80–94 μm3

High Values
Pernicious anemia, alcoholism, vitamin B12 or folate deficiency

Low Values
Iron-deficiency anemia, blood loss, thalassemia, chronic disease

Question 7

Mean corpuscular hemoglobin (MCH)

Answer 7

27–32 pg

High Values
Macrocytic anemia

Low Values
Chronic blood loss, microcytic anemia

Question 8

Mean corpuscular hemoglobin concentration

Answer 8

33.4–35.5 g/dl

Sickle cell anemia

Low valuee
Microcytic and macrocytic anemias

Question 9

Bicarbonate (carbon diox- ide) (total)

Answer 9

18–30mEq/l

Low Value
Metabolic alkalosis

High Value
Metabolic acidosis (kidney disease, liver failure, diarrhea)

Question 10

Calcium (total)

Answer 10

9–11mg/dl; 4.5–5.5mEq/l

Low Value
Hyperparathyroidism (tumor), sarcoidosis, mul- tiple myeloma, excessive vitamin D intake, Paget’s disease

High Value
Hypothyroidism, osteomalacia

Question 11

Chloride

Answer 11

98–106mEq/l

High Value
Metabolic acidosis, renal tubular acidosis

Low Value
Addison’s disease, heart fail- ure, syndrome of inappropriate diuretic hormone secretion (SIADH)

Question 12

Magnesium

Answer 12

1.8–3.6 mg/dl; 1.5–3.0mEq/l

High Values
Addison’s disease, chronic renal failure, dehydration, diabetic acidosis

Low
Alcoholism, chronic diarrhea, hypoparathyroidism, ulcerative colitis, liver cirrhosis

Question 13

Phosphorus

Answer 13

3–4.5 mg/dl; 1.8–2.3mEq/l (adults)

High
Liver disease, renal fail- ure, hypoparathyroidism

Low
Hyperparathyroidism

Question 14

Potassium

Answer 14

3.5–5.5 mEq/l

High
Kidney failure, Addison’s disease, angiotensin- converting enzyme inhibitors (ACEIs; anti- hypertensive), diuretics, drug abusers, type 1 diabetes

Low
Eating disorders (bulimia—vomiting), sweating, chronic diarrhea

Question 15

Sodium

Answer 15

135–147 mEq/l

High
Cushing’s syndrome, hyperaldosteronism, increased fluid loss (vomiting, diarrhea), excessive dietary salt, NSAIDs, corticosteroids, laxatives, lithium, oral contraceptives

Low
Heart failure, burns, vomiting, dehydration, liver cirrhosis, syndrome of inappropriate diuretic hormone secretion (SIADH), diuretics

Question 16

Alkaline phosphatase

Answer 16

50–160 U/l

High Value
Paget’s disease, biliary obstruction, osteoblastic bone tumors, hyperparathyroidism

Low Value
Protein deficiency

Question 17

Amylase

Answer 17

53–123 U/l

High Values
Acute pancreatitis, pancreatic cancer, intestinal/bile duct blockage, perforated ulcer

Low Values
Toxemia of pregnancy

Question 18

creatine kinase (CK) or creatine phosphoki- nase (CPK)

Answer 18

38–174 U/l 96–140 U/l
10–150 U/l
0–30 U/l 0–40 U/l
(males); (females)

High Values
Bowel obstruction, duodenal ulcer, pancreatic cancer

Low Values
Crohn’s disease, celiac disease, cystic fibrosis

Question 19

Lipase

Answer 19

10–150 U/l

High Values
Liver cirrhosis, hepatitis, infectious mononucleosis, acute myocardial infarction, alcoholism

Low Values
Normal results

Question 20

ALT (SGPT) AST (SGOT)

Answer 20

0–30 U/l 0–40 U/l

High
Recent myocardial infarction, liver disease, hepatitis, skeletal muscle trauma
Low
Normal

Question 21

Albumin

Answer 21

3.5–5.5g/dl

High Value
Dehydration, high protein diet

Low Value
Liver disease, kidney disease

Question 22

Bilirubin

Answer 22

0.1mg/dl

High
Cirrhosis, hepatitis, pancreatic cancer

Low
No concern

Question 23

otal cholesterol (depends on age)

Answer 23

<200mg/dl

High Value
Hereditary, diet, risk of heart disease

Normal

Question 24

Creatinine

Answer 24

0.5–1.4mg/dl

High Values
Chronic kidney disease

Low
Normal

Question 25

Glucose, fasting serum

Answer 25

65–99mg/dl

High

Diabeeteus

Low

Normal

Question 26

Triglycerides

Answer 26

40–200mg/dl

Risk of heart disease

Question 27

Blood urea nitrogen (BUN)

Answer 27

6–20mg/dl

High
Severe dehydration, kidney disease, heart failure, GI bleeding

Low
Low protein diet, malnutrition, over-hydration

Question 28

Uric acid

Answer 28

2.0–4.0mg/dl

High Values
Diabetes, alcoholism, renal failure, lead poisoning

Low Values
Syndrome of inappropriate diuretic hormone (SIADH), Wilson’s disease, Fanconi syndrome