COMSEA PHASE 1 FORM 114 – Integrated Medical Sciences: Comprehensive Exam Questions & Answers

Question 5. A patient with a true penicillin allergy (anaphylaxis) should avoid which class of antibiotics due to potential cross-reactivity? A. Macrolides B. Tetracyclines C. Cephalosporins D. Fluoroquinolones Correct Answer: C Rationale: Cephalosporins share the beta-lactam ring with penicillins, causing cross-reactivity in approximately 1–10% of penicillin-allergic patients, especially with anaphylactic reactions. Question 6. Which immunodeficiency disorder is characterized by the triad of eczema, thrombocytopenia with small platelets, and recurrent infections? A. DiGeorge syndrome B. Wiskott-Aldrich syndrome C. Common variable immunodeficiency D. Chronic granulomatous disease Correct Answer: B Rationale: Wiskott-Aldrich syndrome is characterized by eczema, thrombocytopenia (small platelets), and recurrent infections. T cells may be affected but not absent at birth; thymic shadow is present. Question 7. A patient with Parkinson’s disease experiences fluctuations between “on” periods of good mobility and “off” periods of stiffness and hypomobility. This phenomenon is best described as: A. Dyskinesia B. Akathisia C. On-off phenomenon D. Dystonia Correct Answer: C Rationale: The on-off phenomenon refers to fluctuations in motor response where the patient cycles between “on” periods (good mobility) and “off” periods (hypomobile, stiff), reflecting variability of therapeutic effect. Question 8. In a patient with elevated total peripheral resistance, which hemodynamic finding is most expected? A. Decreased cardiac output B. Widened pulse pressure C. Elevated diastolic blood pressure D. Decreased mean arterial pressure Correct Answer: C Rationale: High TPR causes slower diastolic runoff, leading to elevated diastolic blood pressure. This narrows the pulse pressure rather than widening it. Question 9. A 4-month-old infant with DiGeorge syndrome would most likely have which laboratory finding? A. Elevated serum calcium B. Decreased serum calcium C. Elevated T-cell count D. Increased thymic shadow Correct Answer: B Rationale: DiGeorge syndrome involves parathyroid hypoplasia, leading to hypocalcemia, in addition to thymic aplasia and absent T cells. Question 10. Which medication is safe to use in a patient with a documented penicillin allergy? A. Cefazolin B. Amoxicillin C. Doxycycline D. Penicillin G Correct Answer: C Rationale: Doxycycline is a tetracycline antibiotic with no beta-lactam ring, so it is safe in penicillin allergy. Cefazolin, amoxicillin, and penicillin G are all beta-lactams. Question 11. The gram-positive diplococci described in Question 1 are most likely: A. Staphylococcus aureus B. Streptococcus pneumoniae C. Streptococcus pyogenes D. Enterococcus faecalis Correct Answer: B Rationale: Streptococcus pneumoniae is the classic lancet-shaped, gram-positive diplococcus commonly associated with community-acquired pneumonia, especially in COPD patients. Question 12. Which of the following is a feature of X-linked agammaglobulinemia (Bruton’s disease)? A. Absent T cells B. Absent B cells C. Thymic aplasia D. Recurrent fungal infections Correct Answer: B Rationale: X-linked agammaglobulinemia blocks B cell maturation, leading to absent B cells and low immunoglobulins after maternal antibodies wane at around 6 months. T cells are normal. Question 13. A patient on long-term antipsychotic medication develops involuntary tongue rolling and lip smacking. This is most consistent with: A. Levodopa-induced dyskinesia B. Tardive dyskinesia C. Akathisia D. Dystonia Correct Answer: B Rationale: Tardive dyskinesia involves involuntary movements, often of the face (tongue rolling, lip smacking), caused by chronic blockade of dopamine receptors by antipsychotics. Question 14. Which antibiotic is a fluoroquinolone that is safe in penicillin allergy but carries risks of tendonitis and QT prolongation? A. Cefazolin B. Vancomycin C. Levofloxacin D. Doxycycline Correct Answer: C Rationale: Levofloxacin is a fluoroquinolone that is safe in penicillin allergy but carries risks of tendonitis, QT prolongation, and C. Difficile infection. Question 15. A patient with DiGeorge syndrome would most likely have which cardiac anomaly? A. Tetralogy of Fallot B. Truncus arteriosus C. Ventricular septal defect D. Coarctation of the aorta Correct Answer: C Rationale: DiGeorge syndrome is associated with conotruncal cardiac anomalies, including ventricular septal defect, tetralogy of Fallot, and interrupted aortic arch. Question 16. The characteristic movement disorder seen with peak-dose levodopa therapy is: A. Choreiform movements B. Athetoid movements C. Tremor D. Rigidity Correct Answer: A Rationale: Levodopa-induced dyskinesias are choreiform (rapid, jerky, involuntary) movements that occur at peak drug levels and improve when the dose is lowered. Question 17. In the formula MAP = CO × TPR, if MAP increases and CO remains normal, what must have happened? A. TPR decreased B. TPR increased C. Stroke volume increased D. Heart rate decreased Correct Answer: B Rationale: MAP = CO × TPR. If MAP increases while CO remains constant, TPR must have increased to account for the elevated MAP. Question 18. A patient with chronic granulomatous disease has a defect in: A. T-cell maturation B. B-cell function C. NADPH oxidase pathway D. Complement system Correct Answer: C Rationale: Chronic granulomatous disease is a defect in the NADPH oxidase pathway, leading to inability of phagocytes to kill catalase-positive organisms. Question 19. Which medication is a glycopeptide effective against gram-positive cocci with no cross-reactivity to penicillin? A. Cefazolin B. Vancomycin C. Levofloxacin D. Doxycycline Correct Answer: B Rationale: Vancomycin is a glycopeptide effective against gram-positive cocci. It has no cross-reactivity with penicillins, though it is usually reserved for MRSA or severe penicillin-resistant pneumococcus. Question 20. Early morning dystonia in Parkinson’s disease patients is most likely to occur during: A. Peak-dose periods B. “Off” periods C. “On” periods D. After medication adjustment Correct Answer: B Rationale: Dystonia in Parkinson’s disease usually occurs as an “off” period phenomenon, such as early morning dystonia, when levodopa levels are low. Question 21. The absence of a thymic shadow on chest X-ray in a 4-month-old infant is most consistent with: A. Wiskott-Aldrich syndrome B. DiGeorge syndrome C. CVID D. CGD Correct Answer: B Rationale: Thymic aplasia leading to absent thymic shadow is a hallmark of DiGeorge syndrome, resulting from abnormal development of the 3rd and 4th pharyngeal pouches.