Identify The Normal Values For Each Of The Following Labs ✓ Solved

Identify the normal values for each of the following labs, c

Identify the normal values for each of the following labs, considering normal values across gender, race, age, and pregnancy status when applicable. For each lab: 1) Identify normal values; 2) Identify conditions associated with abnormally low levels; 3) Identify conditions associated with abnormally high levels. Follow this format for each lab: [Lab name] Normal Value by Age, Gender, Race, & Pregnancy state; Decreased conditions – ...; Increased conditions – ... Labs to address: CMP (Sodium, Chloride, Potassium, Glucose, CO2, Magnesium, Phosphorus, Calcium), Hemoglobin A1C, Renal Function Tests (BUN, Creatinine, BUN/Cr Ratio, GFR), GI labs (ALT, AST, ALP, GGT, Bilirubin [direct/indirect], Albumin, Protein, Amylase, Lipase), Miscellaneous (Coags - PT/INR, PTT), Inflammatory markers (CRP, ESR), Lipid panel (Total cholesterol, LDL, HDL, Triglycerides).

Paper For Above Instructions

This paper summarizes normal laboratory values for commonly ordered tests across age, gender, race, and pregnancy status where applicable, and lists common clinical conditions associated with decreased and increased results. Values reflect typical adult reference ranges; pediatric and pregnancy variations and common pathologic causes are noted where clinically relevant. References are provided for each category.

Comprehensive Metabolic Panel (CMP)

Sodium

Normal Value by Age/Gender/Race/Pregnancy: Adults 136–145 mEq/L; infants and children slightly variable (infants ~139–146, children ~138–145) and pregnancy often within normal adult range though mild dilutional hyponatremia can occur in late pregnancy [1][2].

Decreased conditions – Syndrome of inappropriate ADH (SIADH), heart failure, cirrhosis, nephrotic syndrome, excessive IV hypotonic fluids, adrenal insufficiency, severe vomiting/diarrhea, diuretic use [1].

Increased conditions – Dehydration, diabetes insipidus (hypernatremia when water loss), excessive sodium intake, hyperaldosteronism, osmotic diuresis (uncontrolled hyperglycemia) [1].

Chloride

Normal: Adults 98–107 mmol/L; shifts parallel sodium and acid–base status; pregnancy usually similar to nonpregnant values [1].

Decreased conditions – Metabolic alkalosis, vomiting, diuretic use, chronic respiratory acidosis [1].

Increased conditions – Metabolic acidosis, dehydration, hyperchloremic states, renal tubular acidosis [1].

Potassium

Normal: Adults 3.5–5.0 mmol/L; children similar; slight physiologic changes in pregnancy but generally within range [1].

Decreased conditions – Diuretics, vomiting, diarrhea, hyperaldosteronism, insulin excess, magnesium depletion [1].

Increased conditions – Renal failure, hemolysis (pseudohyperkalemia), ACE inhibitors/ARBs, potassium-sparing diuretics, metabolic acidosis, tissue breakdown (rhabdomyolysis) [1].

Glucose (fasting)

Normal fasting: 70–99 mg/dL in adults; children have age-specific ranges; pregnancy fasting targets tighter and gestational diabetes screening uses different thresholds [3].

Decreased conditions – Insulinoma, medications (insulin, sulfonylureas), critical illness, alcohol hypoglycemia [3].

Increased conditions – Diabetes mellitus, stress hyperglycemia, corticosteroids, Cushing’s syndrome [3].

CO2 (Bicarbonate, total CO2)

Normal: 22–28 mmol/L adults; varies with acid–base status; pregnancy tends toward mild respiratory alkalosis and slightly lower bicarbonate [1].

Decreased conditions – Metabolic acidosis (DKA, lactic acidosis, renal failure, diarrhea) [1].

Increased conditions – Metabolic alkalosis (vomiting, diuretic use, hyperaldosteronism) [1].

Magnesium

Normal: 1.7–2.2 mg/dL (0.7–0.95 mmol/L) in adults; infants/children have age-adjusted ranges; pregnancy may show slight decreases due to hemodilution [1].

Decreased conditions – Malnutrition, alcoholism, diuretics, proton pump inhibitors, malabsorption, pregnancy (severe preeclampsia shows low magnesium clinically) [1].

Increased conditions – Renal failure, magnesium-containing antacids/IV therapy, hypothyroidism [1].

Phosphorus (Phosphate)

Normal: 2.5–4.5 mg/dL adults; children have higher normal ranges; pregnancy may show lower levels due to hemodilution and increased fetal uptake [1].

Decreased conditions – Refeeding, malnutrition, hyperparathyroidism, vitamin D deficiency, alcoholism [1].

Increased conditions – Renal failure, hypoparathyroidism, tumor lysis syndrome, rhabdomyolysis [1].

Calcium (total)

Normal total calcium: 8.5–10.2 mg/dL adults; ionized calcium is physiologically more relevant; pregnancy often shows normal total calcium but albumin decreases—corrected calcium used [1][4].

Decreased conditions – Hypoparathyroidism, vitamin D deficiency, acute pancreatitis, hypoalbuminemia (low total calcium but normal ionized) [4].

Increased conditions – Hyperparathyroidism, malignancy with bone metastases, vitamin D intoxication, thiazides [4].

Glycemic Markers

Hemoglobin A1c

Normal:

Decreased conditions – Recent significant blood loss or transfusion, hemolytic anemia (can lower A1c) [5].

Increased conditions – Poor glycemic control, iron deficiency anemia (may falsely elevate), chronic hyperglycemia [5].

Renal Function Tests

BUN (Blood Urea Nitrogen)

Normal: 7–20 mg/dL in adults; increases with age and protein intake; pregnancy may lower BUN slightly [6].

Decreased conditions – Liver disease, malnutrition, overhydration [6].

Increased conditions – Prerenal azotemia (dehydration), renal failure, high protein diet, GI bleeding [6].

Creatinine

Normal: Men ~0.74–1.35 mg/dL; women ~0.59–1.04 mg/dL; lower in children and elderly due to muscle mass; pregnancy lowers serum creatinine due to increased GFR [6].

Decreased conditions – Low muscle mass, pregnancy (physiologic) [6].

Increased conditions – Acute kidney injury, chronic kidney disease, rhabdomyolysis [6].

BUN/Cr Ratio

Normal: ~10:1 to 20:1; elevated suggests prerenal azotemia; low may suggest intrinsic renal disease or low protein states [6].

Estimated GFR

Normal: ≥90 mL/min/1.73 m² (age-dependent decline common); staging of CKD uses eGFR cutoffs (CKD if

GI and Hepatic Labs

ALT & AST

Normal ALT: ~7–56 U/L; AST: ~10–40 U/L (gender and lab-specific); pregnancy may modestly alter values [8].

Decreased – Not clinically important if low. Increased – Viral hepatitis, alcoholic liver disease (AST>ALT often), drug-induced liver injury, nonalcoholic fatty liver disease [8].

ALP & GGT

ALP: 44–147 U/L adults (higher in children/pregnancy due to bone and placental isoforms); GGT helps determine hepatic source—elevated with cholestasis and alcohol [8].

Bilirubin (Total/Direct/Indirect)

Normal total: 0.1–1.2 mg/dL; pregnancy may show mild changes; increased direct bilirubin suggests cholestasis, indirect suggests hemolysis or Gilbert syndrome [8].

Albumin & Total Protein

Albumin: 3.5–5.0 g/dL adults; decreased in chronic liver disease, nephrotic syndrome, malnutrition; pregnancy lowers albumin due to dilution [8].

Amylase & Lipase

Amylase normal ~23–85 U/L; lipase ~0–160 U/L (lab-dependent); elevations indicate pancreatitis, obstruction, or other abdominal pathology [9].

Coagulation & Inflammatory Markers

PT/INR and PTT

PT: ~11–13.5 s; INR: ~0.8–1.2 (non-anticoagulated); PTT: ~25–40 s; pregnancy can alter coagulation (hypercoagulable state) [10].

CRP & ESR

CRP:

Lipid Panel

Total Cholesterol / LDL / HDL / Triglycerides

Desirable total cholesterol

Decreased/increased conditions – Dyslipidemias related to metabolic syndrome, hypothyroidism (increased cholesterol), liver disease (low cholesterol in advanced disease), genetic hyperlipidemias, pregnancy raises triglycerides physiologically [12].

Because reference ranges vary by laboratory method, patient demographics, and clinical context, clinicians should use lab-specific reference intervals and adjust interpretation for pregnancy, pediatric patients, elderly patients, race/ethnicity when validated differences exist, and conditions that alter protein binding or red cell lifespan (which affect HbA1c). When values are abnormal, repeat testing, correlate clinically, and pursue targeted diagnostic evaluation per current guidelines [1–12].

References

1. LabTestsOnline. Comprehensive Metabolic Panel (CMP) and related electrolytes: ranges and interpretation. https://labtestsonline.org/ (accessed 2025).
2. MedlinePlus. Electrolytes—sodium, potassium, chloride. U.S. National Library of Medicine. https://medlineplus.gov/ (accessed 2025).
3. American Diabetes Association. Standards of Medical Care in Diabetes—Glycemic targets and A1c interpretation. Diabetes Care. https://diabetes.org/ (accessed 2025).
4. Mayo Clinic Laboratories. Calcium tests and interpretation. https://mayocliniclabs.com/ (accessed 2025).
5. National Glycohemoglobin Standardization Program (NGSP) / CDC. Hemoglobin A1c facts and limitations. https://www.cdc.gov/diabetes/ (accessed 2025).
6. National Kidney Foundation / KDIGO. BUN, creatinine, and GFR interpretation and CKD staging. https://www.kidney.org/ (accessed 2025).
7. KDIGO Clinical Practice Guidelines. Evaluation and management of CKD—eGFR use. https://kdigo.org/ (accessed 2025).
8. American Association for the Study of Liver Diseases (AASLD) / American College of Gastroenterology. LFT interpretation (ALT, AST, ALP, bilirubin, albumin). https://www.aasld.org/ (accessed 2025).
9. American Gastroenterological Association / American College of Gastroenterology guidance on amylase and lipase in pancreatitis. https://gi.org/ (accessed 2025).
10. American Heart Association and American College of Cardiology. Lipid management guidelines and lab targets. https://www.heart.org/ (accessed 2025).