KMU Past Paper Practice
Topic 8 — Insulin Therapy and Acute Diabetic Emergencies: Hypoglycemia, DKA, HHS and Lactic Acidosis
4th Year MBBS • 20 A-type Single Best Answer MCQs • Clinical reasoning and applied concepts :contentReference[oaicite:0]{index=0}
MCQ 1
A patient requiring basal insulin is prescribed insulin detemir. Which pharmacokinetic property contributes importantly to its prolonged duration of action?
Options:
- Formation of insoluble crystals in plasma
- Reversible binding to circulating albumin
- Complex formation with zinc and protamine
- Rapid dissociation into insulin monomers
- Activation of hepatic glucagon receptors
MCQ 2
A student compares modern human insulin with older pancreatic extracts obtained from animals. Which description best identifies the source of most currently used human insulin?
Options:
- Purification from bovine pancreatic tissue
- Chemical conversion of porcine glucagon
- Isolation from human pancreatic donors
- Production using recombinant DNA technology
- Extraction from porcine pancreatic tissue
MCQ 3
A patient injects regular insulin immediately before eating and develops marked post-meal hyperglycemia despite taking the prescribed dose. Which property of regular insulin best explains this mismatch?
Options:
- It forms hexamers that must dissociate before absorption
- It remains permanently bound to subcutaneous albumin
- It is complexed with protamine after injection
- It forms multihexamers with an ultra-long action
- It cannot be absorbed through subcutaneous tissue
MCQ 4
After insulin administration, hepatic glucose output falls substantially in a patient with marked hyperglycemia. Which metabolic process in the liver has been directly suppressed?
Options:
- Protein synthesis
- Glycogen synthesis
- Potassium uptake
- Triglyceride storage
- Gluconeogenesis
MCQ 5
A patient gains several kilograms after previously uncontrolled diabetes is successfully treated with insulin. Which mechanism contributes most directly to this change?
Options:
- Persistent stimulation of urinary glucose loss
- Enhanced breakdown of stored triglycerides
- Reduced calorie loss with increased nutrient storage
- Increased renal excretion of amino acids
- Suppression of skeletal muscle protein synthesis
MCQ 6
A man receiving insulin drinks alcohol without eating and later develops sweating, confusion and a low capillary glucose level. Which hepatic effect of alcohol contributed to the episode?
Options:
- Suppression of gluconeogenesis
- Stimulation of ketone clearance
- Acceleration of glycogen synthesis
- Activation of insulin degradation
- Increase in intestinal glucose absorption
MCQ 7
A patient treated for severe hypoglycemia regains consciousness after intravenous glucose. He had taken a long-acting insulin preparation earlier that day. Which next step is most appropriate?
Options:
- Administer glucagon routinely despite recovery
- Start intravenous insulin to prevent rebound hyperglycemia
- Discharge immediately once consciousness returns
- Continue glucose monitoring for recurrent hypoglycemia
- Restrict further carbohydrate intake for several hours
MCQ 8
Glucagon is administered as rescue treatment to a patient with severe hypoglycemia. Which intracellular signalling pathway is activated in hepatocytes?
Options:
- Receptor tyrosine kinase with GLUT4 translocation
- Gs protein activation with increased cyclic AMP
- Intracellular steroid receptor with gene transcription
- Ligand-gated sodium channel activation
- JAK-STAT signalling with glycogen synthesis
MCQ 9
A 20-year-old patient with DKA has a markedly increased serum anion gap. Which accumulated substances account most directly for this biochemical finding?
Options:
- Sodium and chloride ions
- Glucose and urea molecules
- Albumin and phosphate only
- Bicarbonate and carbon dioxide
- Unmeasured ketoacid anions
MCQ 10
A young adult with severe insulin deficiency has vomiting, dehydration and deep breathing. A characteristic sweet odor is detected on the breath. Which substance is responsible for this finding?
Options:
- Lactic acid
- Beta-hydroxybutyrate
- Acetone
- Pyruvate
- Bicarbonate
MCQ 11
A dehydrated patient with DKA has a serum potassium concentration above the normal range before treatment. Which mechanism best explains this apparently paradoxical finding?
Options:
- Increased intestinal potassium absorption
- Shift of potassium from cells into extracellular fluid
- Suppression of osmotic urinary potassium loss
- Expansion of total-body potassium stores
- Increased potassium synthesis by skeletal muscle
MCQ 12
A patient with suspected DKA undergoes measurement of serum urea and creatinine in addition to glucose, ketones and electrolytes. What is the main clinical purpose of these tests in the acute assessment?
Options:
- Determine the type of circulating ketone
- Confirm autoimmune pancreatic destruction
- Measure the severity of respiratory compensation
- Differentiate human from animal insulin use
- Assess dehydration and renal function
MCQ 13
A 72-year-old patient develops extreme hyperglycemia and severe hyperosmolality but has only minor ketone production. Which metabolic explanation best accounts for the limited ketosis?
Options:
- Residual insulin activity suppresses major lipolysis
- Renal failure eliminates circulating ketones rapidly
- Hyperosmolality completely blocks hepatic metabolism
- Glucagon secretion is absent during severe hyperglycemia
- Adipose tissue becomes unable to release fatty acids
MCQ 14
A patient with HHS begins treatment for profound dehydration and markedly increased plasma osmolality. Why should fluid and metabolic correction be carefully controlled rather than excessively rapid?
Options:
- Rapid treatment stimulates hepatic ketone synthesis
- Rapid treatment prevents renal glucose clearance
- Rapid treatment permanently suppresses endogenous insulin
- Rapid osmotic shifts can produce neurological harm
- Rapid treatment prevents potassium movement into cells
MCQ 15
During a teaching round, the term “hyperosmolar non-ketotic diabetic coma” is replaced with “hyperosmolar hyperglycemic state.” Which observation best supports the modern terminology?
Options:
- Severe hyperglycemia is absent in many cases
- Hyperosmolality is unrelated to neurological symptoms
- Coma is not universal and mild ketosis may occur
- The disorder occurs only in Type 1 diabetes
- Metabolic acidosis is required for diagnosis
MCQ 16
A patient with advanced liver dysfunction develops a high-anion-gap metabolic acidosis and an elevated blood lactate concentration despite no evidence of DKA. Which mechanism contributes to lactate accumulation?
Options:
- Increased conversion of lactate into glycogen
- Enhanced renal excretion of lactate
- Suppression of anaerobic metabolism
- Reduced hepatic clearance of lactate
- Accelerated conversion of lactate into bicarbonate
MCQ 17
A patient has severe metformin-associated lactic acidosis with marked renal failure and persistent metabolic disturbance despite initial supportive treatment. Which additional intervention may be required under specialist care?
Options:
- Renal replacement therapy
- High-dose glucagon therapy
- Continuous oral glucose administration
- Long-acting insulin as sole treatment
- Restriction of oxygen supplementation
MCQ 18
An 11-year-old child has several weeks of polyuria, polydipsia and weight loss. A random plasma glucose concentration is 224 mg/dL. Which interpretation is most appropriate?
Options:
- The result excludes diabetes because fasting glucose was not measured
- The result indicates hypoglycemia requiring immediate carbohydrate
- The result with classic symptoms supports a diagnosis of diabetes
- The result is diagnostic only if urinary ketones are absent
- The result requires an oral glucose load before any interpretation
MCQ 19
A 13-year-old child is newly diagnosed with Type 1 diabetes after presenting with thirst and weight loss. He is clinically stable, ketones are absent and there is no metabolic acidosis. Which management principle is most appropriate?
Options:
- Delay therapy until ketones become detectable
- Treat initially with glucagon before meals
- Manage with dietary restriction alone
- Use an oral hypoglycemic drug as first-line replacement
- Start insulin replacement with family education
MCQ 20
An 8-year-old child with established Type 1 diabetes develops fever and reduced appetite. Home glucose readings are rising, but he is still alert and able to drink. Which additional home assessment is particularly important during the illness?
Options:
- Daily serum calcium measurement
- Ketone testing with more frequent glucose monitoring
- Routine measurement of liver enzymes
- Measurement of urinary protein only
- Immediate oral glucose tolerance testing