Chemical path 2021 — Past Paper OmpathStudy

Chemical Pathology 2021 — Past Paper Questions & Answers Mount Kenya University — School of Medicine Department of Human Physiology Bachelor of Pharmacy (Regular) Unit Code: BPA2203 Unit Title: Chemical Pathology Date: Thursday 29th April 2021, 8:00 AM Duration: 2 Hours --- Part A: Multiple Choice Questions 1. A deficiency of one of the following hormones is likely in a patient with hypernatremia and high serum osmolality. A. Antidiuretic hormone B. Oxytocin C. Insulin D. Growth hormone Answer: A — Antidiuretic hormone Explanation: ADH deficiency (central diabetes insipidus) impairs renal water reabsorption, causing excess free-water loss, hypernatremia, and high serum osmolality. --- 2. The body responds to hypoglycemia by: A. Release of insulin and thyroxine B. Release of ketones and proteins C. Release of sorbitol and fructose D. Release of glucagon and epinephrine Answer: D — Release of glucagon and epinephrine Explanation: Counter-regulatory hormones (glucagon, epinephrine, cortisol, growth hormone) raise blood glucose via glycogenolysis and gluconeogenesis; insulin secretion is suppressed during hypoglycemia. --- 3. Nephrotic syndrome is characterized by all except: A. Hypocholesterolemia B. Hypoalbuminemia C. Albuminuria D. Hypertriglyceridemia Answer: A — Hypocholesterolemia Explanation: Nephrotic syndrome causes hyper cholesterolemia (increased hepatic lipoprotein synthesis in response to low oncotic pressure), not hypocholesterolemia. Hypoalbuminemia, heavy proteinuria (albuminuria), and hypertriglyceridemia are all classic features. --- 4. Chronic renal failure is diagnosed by: A. Decreased blood urea B. Increased creatinine C. Hematuria D. Glucosuria Answer: B — Increased creatinine Explanation: Serum creatinine rises as GFR declines, making it a standard marker for renal impairment; urea also rises but is less specific (affected by diet, hydration, catabolism). --- 5. Fluoride is the anticoagulant used in testing blood for: A. Blood sugar B. Coagulation C. Electrolyte D. CBC Answer: A — Blood sugar Explanation: Sodium fluoride inhibits glycolysis (enolase inhibition), preventing in-vitro glucose consumption by red cells, thus preserving true glucose levels. --- 6. In a 15-year-old male patient with polydipsia and polyuria, a fasting serum glucose of 13 mmol/L, the most likely diagnosis is: A. Gestational diabetes mellitus B. Type I diabetes mellitus C. Non-insulin dependent diabetes mellitus D. Pancreatic islet cell tumor (glucagonoma) Answer: B — Type I diabetes mellitus Explanation: Young age with classic osmotic symptoms and hyperglycemia points to autoimmune beta-cell destruction and absolute insulin deficiency (Type I), rather than insulin resistance (Type II). --- 7. In type 1 diabetes mellitus, insulin is: A. Increased B. Low C. Normal D. Correlated to age of patient Answer: B — Low Explanation: Type 1 DM results from autoimmune destruction of pancreatic beta cells, causing an absolute deficiency of insulin. --- 8. The test used to monitor the glycemic status of patients over a period of three to four months is: A. Uristix B. Fasting blood sugar C. Fructosamine D. HbA1c Answer: D — HbA1c Explanation: Glycation of hemoglobin reflects average blood glucose over the ~120-day lifespan of red cells, giving a 3-month glycemic picture. Fructosamine reflects a shorter window (~2–3 weeks, glycated albumin). --- 9. One of the following enzymes shows the greatest specificity in liver damage? A. LDH B. ALP C. AST D. ALT Answer: D — ALT Explanation: LDH is present in many tissues (heart, muscle, liver, RBCs); ALP is also found in bone and placenta; AST is present in liver and skeletal/cardiac muscle. ALT is predominantly cytosolic in hepatocytes, making it the most liver-specific of these enzymes. --- 10. One of the following enzymes may differentiate between liver disease and active bone growth in a teenage patient: A. ALP B. GGT C. ALT D. CK Answer: B — GGT Explanation: Both liver disease and physiological bone growth in adolescents can raise ALP. GGT is not produced by bone and remains normal in isolated bone growth, so a raised GGT alongside raised ALP points to a hepatobiliary source rather than bone. --- 11. A patient's blood gas results are: pH = 7.50, PCO2 = 55 mm Hg, HCO3⁻ = 40 mmol/L. These results indicate: A. Respiratory acidosis B. Metabolic alkalosis C. Respiratory alkalosis D. Metabolic acidosis Answer: B — Metabolic alkalosis Explanation: pH is high (alkalosis). HCO3⁻ is markedly elevated (primary metabolic alkalosis), while the raised PCO2 represents appropriate respiratory compensation (hypoventilation retaining CO2). --- 12. Which set of results is consistent with uncompensated respiratory alkalosis? A. pH 7.70, HCO3 30 mmol/L, PCO2 25 mm Hg B. pH 7.66, HCO3 22 mmol/L, PCO2 20 mm Hg C. pH 7.46, HCO3 38 mmol/L, PCO2 55 mm Hg D. pH 7.36, HCO3 22 mmol/L, PCO2 38 mm Hg Answer: B — pH 7.66, HCO3 22 mmol/L, PCO2 20 mm Hg Explanation: Uncompensated respiratory alkalosis shows a markedly e