Laboratory Values & Diagnostics Practice Test 1
Laboratory Values & Diagnostics NCLEX Practice Test
Laboratory Values & Diagnostics is a key topic within the NCLEX test plan, located under Nursing Science → Clinical Foundations → Laboratory Values & Diagnostics. This section interprets key lab data and integrates findings into clinical nursing judgment. Each test contains 50 questions designed to mirror the difficulty and variety of the real exam.
This is the 1st part of the Laboratory Values & Diagnostics series. To explore all practice tests under this topic, use the “Back to Main Topic” button at the end of the page.
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Laboratory Values & Diagnostics Practice Test 1
What is the normal range of cerebrospinal fluid pressure in mm Hg?
- 80 to 120
- 60 to 170
- 40 to 150
- 50 to 180
Explanation: Answer reason: The normal CSF opening pressure at lumbar puncture is about 50–180 mm H2O (often listed as 60–200 mm H2O). Among the options, this corresponds to 50–180.
What does an electrocardiograph (ECG) measure?
- Blood count
- Heartbeat
- Temperature
- Electricity
Explanation: Answer reason: An ECG records the heart’s electrical activity (electrical potentials), from which heart rate and rhythm are derived. It does not measure blood count or temperature.
At what level and at what gestational age do hGG levels typically peak in maternal circulation?
- 100,000 mIU/mL at 10 weeks
- 10,000 mIU/mL at 10 weeks
- 10,000 mIU/mL at 20 weeks.
- 100,000 mIU/mL at 40 weeks.
Explanation: Answer reason: HCG rises rapidly in early pregnancy, peaks around 8–10 weeks at approximately 100,000 mIU/mL, and then declines, matching option A.
What is the normal cholesterol level in mg/dL?
- 200–100 mg/dL
- 160–150 mg/dL
- 120 - 80 mg/dL
- 150–200 mg/dL
Explanation: Answer reason: Desirable total cholesterol is less than 200 mg/dL; many references cite a normal range of 150–200 mg/dL, matching option D.
What is the normal pH range for arterial blood?
- 7:35 to 7:45
- 6.8 to 7.0
- 7.50 to 7.60
- 7.0 to 7.2
Explanation: Answer reason: Normal arterial blood pH is 7.35–7.45, reflecting tightly regulated acid–base homeostasis.
What is the normal arterial blood pH range maintained by the ratio of sodium bicarbonate to carbon dioxide?
- 7.35-7.45
- 7.25–7.35
- 7:45–7:55
- 7:15–7:25
Explanation: Answer reason: Arterial blood pH is normally maintained at 7.35–7.45 by the bicarbonate (HCO3−)–carbon dioxide (CO2) buffer system per Henderson–Hasselbalch.
Which test is used to detect urine specific gravity?
- Urine specific gravity test
- Pregnancy test
- PID test
- Salpingitis test
Explanation: Answer reason: Urine specific gravity is measured directly by a urinalysis specific gravity test; the other options assess different conditions and do not measure urine concentration.
Which laboratory test is used to identify injury to the myocardium and can remain elevated for up to three weeks?
- Total CK
- CK-MB
- Myoglobin
- Troponin T or I
Explanation: Answer reason: Troponins are cardiac-specific proteins that remain elevated longer than CK-MB, confirming myocardial injury.
Hey's test is used to test for which substance?
- Bile salts
- Albumin
- Bile pigments
- Acetone
Explanation: Answer reason: Hay's sulfur test detects bile salts in urine because bile salts lower surface tension, causing sulfur powder to sink.
What is the name of this instrument?
- LV cannula
- Vessel dilator
- Lumbar puncture needle
- Long needle
Explanation: Answer reason: The specialized instrument for performing a spinal tap is a lumbar puncture needle; the other options are nonspecific or different devices.
Does an ultrasound examination have any side effects on a foetus?
- Yes
- No
- Sometimes
Explanation: Answer reason: Diagnostic ultrasound uses non‑ionizing sound waves and, when performed appropriately, has no known harmful effects on the fetus (ALARA principle applies).
Which is the specific diagnostic test for cystic fibrosis?
- Positive sweat chloride test
- Chest X-ray
- Pulmonary function test.
- 72-hour stool sample collection
Explanation: Answer reason: A positive sweat chloride test is the specific diagnostic test for cystic fibrosis due to elevated chloride concentrations in sweat. Chest x-ray, PFTs, and stool fat studies are supportive but not specific.
The VDRL test is done for the diagnosis of?
- Tuberculosis
- Diphtheria
- Syphilis
- Typhoid
Explanation: Answer reason: VDRL (Venereal Disease Research Laboratory) is a non-treponemal serologic screening test used to detect syphilis.
What is the normal potassium level of blood?
- 2.1-5 mmol/L
- 3.2-5 mmol/L
- 3.3-5 mmol/L
- 4.4-5 mmol/L
- 3.5-5 mmol/L
Explanation: Answer reason: Normal serum potassium is approximately 3.5–5.0 mmol/L; other ranges are incorrect.
What is the best indicator of kidney function?
- BUN
- Serum creatinine
- Hemoglobin
- Potassium
Explanation: Answer reason: Serum creatinine most specifically reflects glomerular filtration and is the best single laboratory indicator of renal function; BUN is influenced by hydration and protein intake, and hemoglobin and potassium are not primary measures of kidney function.
Which blood test helps support appendicitis diagnosis?
- Platelets
- Hb
- ESR
- WBC count
Explanation: Answer reason: Acute appendicitis typically presents with leukocytosis; an elevated WBC count supports the diagnosis.
In the assessment of fetal growth, which parameters are considered in the calculation of the estimated fetal weight (EFW)?
- Biparietal diameter (BPD) and femur length (FL)
- Amniotic fluid index (AFI) and placental thickness
- Abdominal circumference (AC) and head circumference (HC)
- Nuchal translucency (NT) and crown-rump length (CRL)
- Nuchal translucency (NT) and crown-rump thickness
Explanation: Answer reason: EFW formulas (e.g., Hadlock) use fetal biometric measurements, notably AC and HC (often with FL/BPD). AFI, placental thickness, and NT/CRL are not used for weight estimation.
Which Scanning procedure is safe in Obstetric practice ?
- X_ray
- CT_scan
- MRI
- Ultrasound
Explanation: Answer reason: Ultrasound uses sound waves and no ionizing radiation, making it the safest and standard imaging modality in pregnancy. X-ray and CT involve ionizing radiation; MRI is generally safe but not the routine first-line in obstetrics.
The six limb leads you apply will give you information about what area of the patient's heart?
- The frontal plane
- The horizontal plane
- The vertical plane
- The posterior plane
Explanation: Answer reason: Limb leads I, II, III, aVR, aVL, and aVF view the heart's electrical activity in the frontal plane; precordial leads view the horizontal plane.
How is diabetes typically diagnosed?
- Urine test
- Tissues bioassay
- Blood test
- Medical history
Explanation: Answer reason: Diabetes is diagnosed by measuring blood glucose (e.g., fasting plasma glucose, HbA1c, or oral glucose tolerance), which are blood tests.
What is the effect of Down syndrome on AFP level?
- AFP is low
- AFP is high
- No effect on AFP
- None of the above
Explanation: Answer reason: Maternal serum alpha-fetoprotein is decreased in pregnancies affected by trisomy 21 (Down syndrome) as part of the quad/triple screen.
What is the most sensitive test for diagnosis of iron deficiency anemia in the community?
- Serum ferritin level
- Serum transferase saturation
- Serum iron level
- Hemoglobin (HB) level
Explanation: Answer reason: Serum ferritin best reflects body iron stores and is the earliest, most sensitive indicator of iron deficiency compared with serum iron, transferrin saturation, or hemoglobin.
What is the primary use of laparoscopy?
- Diagnosing conditions within the abdominal or pelvic cavity
- Treating external injuries
- Performing non-invasive cosmetic surgery
- Administering anesthesia
Explanation: Answer reason: Laparoscopy is a minimally invasive endoscopic procedure that allows direct visualization and biopsy within the abdominal and pelvic cavities, primarily for diagnosis. It is not used to treat external injuries, perform cosmetic surgery, or administer anesthesia.
An invasive visual diagnostic procedure that is used to examine the interior surfaces of an organ or tissue is?
- Endoscopy
- MRI
- Parenthesis
- X-Ray
Explanation: Answer reason: Endoscopy is an invasive procedure that directly visualizes internal organ surfaces; MRI and X-ray are noninvasive imaging modalities, and 'Parenthesis' is not a diagnostic procedure.
Which lab investigation indicates massive cell destruction during chemotherapy?
- Decrease uric acid in blood
- Increase uric acid in blood
- Hypokalemia
- Decrease bleeding time (BT)
Explanation: Answer reason: Tumor lysis from chemotherapy releases nucleic acids that are metabolized to uric acid, producing hyperuricemia—an indicator of massive cell destruction.
What is the best test for liver dysfunction?
- SGPT
- Serum Albumin
- Serum Bilirubin
- PT
Explanation: Answer reason: Prothrombin time best reflects hepatic synthetic function and changes quickly with liver dysfunction due to short half-life of clotting factors (especially factor VII). Albumin changes slowly; SGPT and bilirubin indicate injury or cholestasis rather than overall function.
In case of bile duct damage, which laboratory value will increase?
- ALT
- AST
- ALP
- WBC
Explanation: Answer reason: Alkaline phosphatase rises prominently with cholestasis and bile duct injury, while ALT/AST reflect hepatocellular damage and WBC elevation indicates infection, not specifically biliary obstruction.
The nurse is preparing a client for a fasting lipid panel. Which instruction is essential to ensure accurate diagnostic results?
- Avoid all fluid intake for 12 hours
- Maintain normal diet until the morning of the test
- Do not consume food or caloric beverages for 12 hours before the test
- Eat a low-fat meal the night before the test
Explanation: Answer reason: A fasting lipid panel requires 12 hours of fasting from food and caloric beverages to ensure accurate measurement of LDL, HDL, and triglyceride levels. Water is allowed and does not affect the test.
The Normal Fasting blood glucose level is?
- 80-110/mgdl
- 150-200/mgdl
- 300-350/mgdl
- 30-50/mgdl
Explanation: Answer reason: Normal fasting plasma glucose is about 70–100 mg/dL; older references accept 80–110 mg/dL. The other ranges are clearly abnormal.
What is the normal WBC count?
- 1,000-4,000/mm³
- 4,000-11,000/mm³
- 12,000-20,000/mm³
- 25,000-50,000/mm³
Explanation: Answer reason: Normal adult leukocyte count is about 4,000–11,000 per mm³; values below indicate leukopenia and above indicate leukocytosis.
Which test can be used for the diagnosis and assessment of the severity of heart failure?
- BNP
- PSA
- Troponin
- ANA
Explanation: Answer reason: BNP (B-type natriuretic peptide) rises with ventricular stretch and volume overload, aiding in the diagnosis and severity assessment of heart failure. PSA is for prostate disease, troponin for myocardial infarction, and ANA for autoimmune disorders.
What is the normal range for cholesterol levels?
- 150 mg/dL
- 239 mg/dL
- 300 mg/dL
- Not specified
Explanation: Answer reason: Desirable total cholesterol is <200 mg/dL; 200–239 mg/dL is considered borderline. Among the single-value options, 239 mg/dL best represents the upper threshold near the normal/borderline range.
What does a ferritin level test assess?
- The amount of hemoglobin in the body
- How much iron may be stored in the body
- The ability of the blood to clot
- The number of white cells in the body
Explanation: Answer reason: Ferritin is the primary intracellular iron-storage protein; serum ferritin reflects body iron stores.
Which of the following tests is used for the diagnosis of tuberculosis (TB)?
- Widal test
- TST
- A1C
- RDTs
Explanation: Answer reason: TST (tuberculin skin test) is used to detect TB infection. Widal is for typhoid fever, A1C assesses glycemic control, and RDTs are commonly for malaria.
What is the normal blood cholesterol level?
- 100-150 mg%
- 150-250 mg%
- 50-100 mg%
- 250-300 mg%
Explanation: Answer reason: Normal total serum cholesterol has traditionally been cited around 150–250 mg% (mg/dL), with desirable values <200 mg/dL; among the choices, 150–250 mg% is the correct reference range.
Which of the following is the best indicator of the diagnosis of HIV?
- White blood cell count
- ELISA
- Western Blot
- Complete blood count
Explanation: Answer reason: ELISA is a screening test, while Western Blot is the traditional confirmatory test for diagnosing HIV; CBC/WBC are nonspecific.
Which laboratory test would be the least effective in making the diagnosis of a myocardial infarction?
- AST
- Troponin
- CK-MB
- Myoglobin
Explanation: Answer reason: AST is a nonspecific enzyme largely associated with liver injury and is obsolete for MI diagnosis, whereas troponin and CK-MB are cardiac-specific and myoglobin, though nonspecific, is useful for early detection. Thus AST is least effective.
Which test is used to check the patency of the ureter?
- Barlow test
- Plethysmography
- Sulkowitch test
- Buret test
Explanation: Answer reason: Sulkowitch test is a urologic urine test historically used to assess ureteral patency.
Which of the following instruments is used for recording the electrical activity of the brain?
- ECG
- EMG
- PCG
- EEG
Explanation: Answer reason: EEG (electroencephalogram) records the brain's electrical activity. ECG records heart activity, EMG records muscle activity, and PCG records heart sounds.
The PT (prothrombin time) test is a function test of which organ?
- Brain
- Kidney
- Lungs
- Liver
Explanation: Answer reason: PT assesses the extrinsic/common coagulation pathway; most clotting factors are synthesized in the liver, so prolonged PT indicates impaired hepatic synthetic function.
After death, which substance does NOT show a rise in cerebrospinal fluid (CSF)?
- Lactic acid
- Amino acid
- Urea
- Uric acid
Explanation: Answer reason: Postmortem CSF shows increases in lactic acid (anaerobic metabolism), amino acids (proteolysis), and urea; uric acid does not typically rise.
The Banne test is used for diagnosis of which disease?
- Syphilis
- Infectious mononucleosis
- Typhoid fever
- Scarlet fever
Explanation: Answer reason: The Paul-Bunnell (often shortened/misattributed as Banne) test detects heterophile antibodies characteristic of Epstein-Barr virus infection, diagnosing infectious mononucleosis.
Which of the following crystals may be found in acidic urine?
- Calcium carbonate
- Calcium oxalate
- Calcium phosphate
- Triple phosphate
Explanation: Answer reason: Calcium oxalate crystals commonly form in acidic urine, whereas calcium carbonate, calcium phosphate, and triple phosphate are typically seen in alkaline urine.
What bilirubin level indicates pathological jaundice?
- 0.4 to 1.2 mg/dL
- More than 5 mg/dL
- More than 12 mg/dL
- More than 15 mg/dL
Explanation: Answer reason: In neonates, pathologic jaundice is suggested when total bilirubin exceeds about 5 mg/dL within the first 24 hours or rises rapidly; thus >5 mg/dL indicates pathological jaundice.
Which condition most likely caused a serum phosphorus level of 1.8 mg/dL (0.45 mmol/L)?
- Malnutrition
- Renal insufficiency
- Hypoparathyroidism
- Tumor lysis syndrome
Explanation: Answer reason: 1.8 mg/dL indicates hypophosphatemia. Malnutrition leads to decreased phosphate intake and low serum phosphate, whereas renal insufficiency, hypoparathyroidism, and tumor lysis syndrome typically cause hyperphosphatemia.
What is the normal albumin to globulin ratio in blood serum?
- A ratio greater than 2.5
- A ratio between 1.0 and 2.5
- A ratio less than 1.0
- A ratio equal to 0
Explanation: Answer reason: Normal serum albumin/globulin (A/G) ratio is slightly over 1, typically about 1.0–2.5, so the best option is the range between 1.0 and 2.5.
Which test is used to detect HIV?
- Per
- Elisa
- Widal
- A and b both
Explanation: Answer reason: ELISA is a standard screening test for HIV. Widal is for typhoid, and 'per' is not a recognized HIV test, so 'a and b both' is incorrect.
Benedict's test in a urine sample is done for detection of which substance?
- Acetone
- Bile salt
- Glucose
- Bile pigment
Explanation: Answer reason: Benedict’s test detects reducing sugars; in urine it is used to identify glucosuria. Acetone, bile salts, and bile pigments have different specific tests.
Paracenthesis is defined as?
- Radiological examination of Gall Bladder
- Examination of the Large bowel
- Stool assessment
- Removal of peritoneal fluids for analysis
Explanation: Answer reason: Paracentesis is the procedure of removing fluid from the peritoneal cavity, typically for diagnostic analysis or therapeutic relief. The other options describe unrelated tests.
Due to a patient's health, specimens can also be lipemic. What describes a lipemic sample?
- A thickened buffy coat
- Pink or red in color
- Hazy, opaque, or milky white
- Deep yellow, brown, or green
Explanation: Answer reason: Lipemia is caused by high lipids in the specimen, producing a turbid, milky appearance. Pink/red indicates hemolysis, and deep yellow/brown/green indicates icteric samples.
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