AMC MCQ - Australian Medical Council Multiple Choice Questions Musculoskeletal and Dermatology Questions and Answers 1 — Questions and Answers
Question 1: A 65-year-old man with a history of chronic kidney disease (eGFR 40 mL/min/1.73m²) and peptic ulcer disease presents with an acutely painful, swollen, and red left great toe. Arthrocentesis confirms the presence of negatively birefringent, needle-shaped crystals. What is the most appropriate first-line treatment for his acute gout flare?
- Allopurinol
- Indomethacin
- Prednisolone (Correct answer)
- Colchicine
Correct answer: Prednisolone
In a patient with an acute gout flare, the primary goal is to manage pain and inflammation. NSAIDs like indomethacin are contraindicated due to the patient's chronic kidney disease and history of peptic ulcer disease. Allopurinol is a urate-lowering therapy used for long-term prevention and should not be initiated during an acute flare as it can prolong the attack. While colchicine can be used, it requires dose adjustment in renal impairment and has a narrow therapeutic window with potential for significant gastrointestinal side effects. Therefore, oral corticosteroids such as prednisolone are the safest and most appropriate first-line choice in this clinical scenario.
Question 2: A 45-year-old construction worker presents for a routine skin check. When evaluating a pigmented skin lesion for suspected melanoma, which of the following features is considered the single most important predictor of prognosis?
- Asymmetry of the lesion
- Breslow thickness (Correct answer)
- Diameter greater than 6 mm
- Irregularity of the border
Correct answer: Breslow thickness
Breslow thickness, which is the vertical depth of tumour invasion measured in millimetres, is the single most powerful prognostic factor for primary cutaneous melanoma. [1, 3, 4] While asymmetry, border irregularity, and diameter are important clinical features for identifying suspicious lesions (part of the ABCDE criteria), the depth of invasion directly correlates with the risk of metastasis and overall survival. [1, 4] A thicker tumour has a higher likelihood of spreading to lymph nodes and distant sites, leading to a poorer prognosis.
Question 3: A 68-year-old woman undergoes a DEXA scan which reveals a T-score of -2.8 at the femoral neck. She has no personal history of fragility fractures. According to Australian guidelines, which of the following is the most appropriate first-line pharmacological treatment for her postmenopausal osteoporosis?
- Denosumab
- Teriparatide
- Raloxifene
- Alendronate (Correct answer)
Correct answer: Alendronate
According to Australian and international guidelines, oral bisphosphonates such as alendronate are the recommended first-line pharmacological treatment for most postmenopausal women with osteoporosis. [35, 43] They are effective in reducing the risk of vertebral and non-vertebral fractures, are widely available, and cost-effective. Denosumab is typically considered a second-line option or for those who cannot tolerate bisphosphonates. Teriparatide is an anabolic agent reserved for severe osteoporosis with multiple fractures. Raloxifene is less effective at preventing non-vertebral fractures and is not typically a first-line choice for this patient profile. [14]
Question 4: A 25-year-old childcare worker is diagnosed with scabies after presenting with an intensely pruritic rash that is worse at night, affecting her finger web spaces and wrists. What is the most crucial component of her management plan to prevent re-infestation and spread?
- Applying topical permethrin cream only to the visibly affected areas of skin
- Prescribing a course of oral antibiotics to prevent secondary infection
- Simultaneously treating all household members and close contacts, regardless of symptoms (Correct answer)
- Washing all bed linen and clothing in cold water with standard detergent
Correct answer: Simultaneously treating all household members and close contacts, regardless of symptoms
Effective management of scabies requires the simultaneous treatment of the infected individual and all of their close household and sexual contacts, even if they are asymptomatic. [7, 12, 30] This is because contacts can be infested but remain in the asymptomatic incubation period (which can be several weeks), acting as a reservoir for re-infestation. Topical treatment must be applied to the entire body, not just affected areas. Linen should be washed in hot water. Antibiotics are only used for secondary bacterial infections, not the primary infestation.
Question 5: A 35-year-old intravenous drug user presents to the emergency department with a 2-day history of a severely painful, swollen, and warm right knee, accompanied by a fever of 38.8°C. He is unable to bear weight on the leg. Which of the following investigations is the most critical for establishing a definitive diagnosis of septic arthritis?
- Synovial fluid analysis and culture (Correct answer)
- Plain radiograph of the knee
- Serum C-reactive protein (CRP) and Erythrocyte Sedimentation Rate (ESR)
- Blood cultures
Correct answer: Synovial fluid analysis and culture
The gold standard and most critical investigation for diagnosing septic arthritis is arthrocentesis followed by synovial fluid analysis (for cell count, Gram stain, and crystals) and culture. [2, 5, 10] This directly identifies the presence and type of infection within the joint space. While serum inflammatory markers (CRP, ESR) are usually elevated, they are non-specific. [13] Blood cultures are important as they may be positive but can be negative even with joint infection. Plain radiographs are often normal in the early stages of septic arthritis.
Question 6: A 72-year-old retired farmer presents with a slowly growing lesion on his nose that has been present for over a year and occasionally bleeds. Which of the following descriptions is most characteristic of a nodular basal cell carcinoma?
- A rapidly growing, ulcerated nodule with a central keratin core
- A flat, scaly, erythematous patch on a sun-exposed area
- An irregularly pigmented macule with significant colour variation
- A pearly, translucent papule with telangiectasia and a rolled border (Correct answer)
Correct answer: A pearly, translucent papule with telangiectasia and a rolled border
The classic clinical presentation of nodular basal cell carcinoma (BCC), the most common subtype, is a pearly or translucent papule or nodule that often features fine, superficial blood vessels (telangiectasia) and a distinct, raised, or 'rolled' border. [17, 21, 31] A rapidly growing nodule with a keratin core is more suggestive of a keratoacanthoma or squamous cell carcinoma (SCC). A flat, scaly patch suggests actinic keratosis or superficial BCC. An irregularly pigmented macule is highly suspicious for melanoma.
