Mock Rheumatology Module 4

A 25-year-old woman presents with a 3-month history of joint aching and stiffness in her hands and wrists, significant fatigue, and Raynaud’s phenomenon. She takes minocycline for acne. Examination shows mild synovitis without deformity and no rash.

Investigations:

• Haemoglobin 103 g/L [115–165]
• Lymphocytes 0.9 ×10⁹/L [1.0–4.0]
• ESR 52 mm/h [<20]
• Rheumatoid factor 125 IU/mL [<20]
• ANA 1:320 speckled
• U1-RNP antibody strongly positive
• Anti-dsDNA 9 IU/mL [<7]
• Anti-Sm negative
• Anti-Scl-70 negative
• Anti-centromere negative.

Which of the following is the most likely diagnosis?

A 54-year-old woman presents with a 3-month history of symmetrical polyarthralgia of the hands, wrists and knees, worse in the mornings and improving with activity, with fatigue and a photosensitive facial rash.

Examination shows MCP and PIP synovitis without deformity and a malar rash sparing the nasolabial folds.

Investigations:

• ANA positive
• speckled 1:160 with a cytoplasmic pattern 1:640
• ENA positive for anti-Ro (SS-A)
• anti-ribosomal P positive
• anti-dsDNA 4 IU/mL [<7]
• anti-CCP negative
• rheumatoid factor 45 IU/mL [<20]

Which of the following is the most likely diagnosis?

A 54-year-old woman with long-standing rheumatoid arthritis on methotrexate and infliximab presents with 6 weeks of polyarthralgia, a photosensitive malar rash, lower-limb palpable purpura, daily low-grade fever and pleuritic chest pain.

She is febrile (38.0°C). Cardiopulmonary examination reveals pain on deep inspiration without a rub. There is MCP/PIP/wrist synovitis, a left elbow nodule and reduced right wrist movement.

Investigations: rheumatoid factor positive; ANA 1:640; anti-dsDNA positive; chest radiograph shows small bilateral pleural effusions.

Which antibody is most likely to be present?

Anti-TNF therapy is contraindicated in all of the following EXCEPT:

Which of the following is NOT a recognised feature of dermatomyositis?

A 52-year-old woman presents to the neuromuscular clinic with a 3-month history of progressive proximal muscle weakness. She reports increasing difficulty climbing stairs, rising from a seated position, and lifting objects above her head.

On examination, she has symmetrical weakness of the shoulder and hip girdle muscles, with preserved distal strength and normal sensation.

Her creatine kinase (CK) is markedly elevated at 4,200 U/L.

A muscle biopsy demonstrates endomysial inflammatory infiltrates with scattered necrotic fibres.

As part of her workup, she undergoes electromyography (EMG) to characterise the pattern of muscle involvement.

Which of the following would you NOT expect to find on this patient’s EMG study?

A 72-year-old man presents with an 18-month history of slowly progressive, painless muscle weakness that began in the fingers (difficulty buttoning and gripping) and later affected rising from a chair and stair-climbing.

Examination shows asymmetric weakness, more marked distally in the forearms/finger flexors and in the quadriceps. Reflexes are normal and there are no sensory deficits.

Creatine kinase is 320 U/L [<200].

What is the most likely diagnosis?

Which of the following drug classes is the most common cause of drug-induced myopathy?

Which of the following is directly involved in cartilage matrix breakdown in osteoarthritis?

A 45-year-old man presents with acute pain, swelling and redness of the left first MTP joint and a diffusely swollen, sausage-like left fourth toe (dactylitis).

He describes intermittent self-limiting inflammatory low back pain over several months and a recent self-resolving episode of diarrhoea.

Examination confirms first-MTP arthritis and fourth-toe dactylitis without rash or conjunctivitis.

Investigations:

• FBE normal
• ESR 28 mm/h [<20]
• serum urate 0.49 mmol/L [0.20–0.42] (elevated)
• rheumatoid factor negative

What is the most likely diagnosis?

A 70-year-old woman presents with intermittent back pain and progressive kyphosis over several years.

History includes hysterectomy (with likely oophorectomy) at 26, sigmoid colectomy for colon cancer, and right knee replacement.

Examination shows severe kyphosis with reduced spinal movement, no bone tenderness and no other musculoskeletal abnormality.

DXA:

• lumbar spine 0.2 SD below age-matched mean, 2.04 SD below young-adult mean (T-score −2.0)
• femoral neck 2.0 SD below age-matched mean, 4.2 SD below young-adult mean (T-score −4.2).

What is the most likely cause of the kyphosis?

A 24-year-old man presents with recurrent inflammatory low back pain: three episodes over five months, each ~10 days, worse at night and early morning, improving with exercise. No trauma, eye, skin or GI symptoms.

Examination shows discomfort on lumbar flexion; neurological examination is normal.

Investigations: FBE normal; ESR 19 mm/h [<15]; HLA-B27 positive; plain radiographs of lumbosacral spine and sacroiliac joints normal.

What is the most likely diagnosis?

In axial spondyloarthritis, early syndesmophytes are most characteristically first seen at which spinal region?

A 24-year-old man presents with 6 months of inflammatory lower back and buttock pain, worse in the morning with >1 hour stiffness improving with exercise.

Examination shows reduced lumbar mobility (modified Schober 3 cm; normal >5 cm) and bilateral sacroiliac tenderness; peripheral joints are normal.

Which investigation would most likely support a diagnosis of axial spondyloarthritis?

A 62-year-old man on weekly oral methotrexate for psoriatic arthritis is inadvertently prescribed trimethoprim-sulfamethoxazole for a urinary tract infection.

He develops mucositis, fever, bruising and moderately severe pancytopenia.

Intravenous folinic acid (calcium folinate/leucovorin) is administered.

What is the principal mode of action of folinic acid?

A 62-year-old Polynesian man presents to the emergency department with a 2-day history of an acutely painful, s wollen and erythematous first metatarsophalangeal joint.

He has had three similar episodes over the past year. His medical history includes stage 3b chronic kidney disease (eGFR 38 mL/min/1.73m²), hypertension, type 2 diabetes mellitus, and ischaemic heart disease with a drug-eluting stent inserted 8 months ago.

His current medications are aspirin, ticagrelor, ramipril, metformin and atorvastatin.

On examination he is afebrile. The affected joint is exquisitely tender, hot and swollen.

Joint aspiration reveals negatively birefringent needle-shaped crystals under polarised light microscopy, with no organisms on Gram stain.

Investigations:

• Serum urate 0.52 mmol/L (0.20–0.42)
• Creatinine 165 µmol/L (60–110)
• eGFR 38 mL/min/1.73m²

Which of the following is the most appropriate treatment for this patient’s acute presentation?

A 52-year-old woman presents with 12 months of progressive pain, stiffness and swelling of the fingers, morning stiffness, and Raynaud’s phenomenon (white–blue–red colour changes).

She reports dysphagia and tightening/thickening of the skin over her face and hands.

Examination shows skin thickening/induration of the fingers and face, puffy fingers with limited joint movement, and prolonged capillary refill, without joint deformity.

X-rays of the hands: resorption of the distal phalangeal tufts (acro-osteolysis), soft-tissue calcification, no significant joint-space narrowing or erosion.

What is the most likely diagnosis?

A 38-year-old woman presents with a 3-week history of progressive pain over the radial aspect of the right wrist, radiating to the thumb, without trauma or systemic symptoms.

Examination reveals localised tenderness just distal to the radial styloid without swelling or erythema; pain is reproduced by ulnar deviation of the wrist with the thumb flexed into the palm.

What is the most likely diagnosis?

Which of the following is the strongest MODIFIABLE risk factor for osteoarthritis of the hip and knee?

A 45-year-old man with type 2 diabetes presents with a 12-month history of progressive pain and stiffness in the hands, and a family history of haemochromatosis.

Examination shows reduced MCP range of movement with swelling and tenderness of the second and third MCP joints.

X-ray: chondrocalcinosis, joint-space narrowing and subchondral sclerosis (especially 2nd/3rd MCP), and characteristic hook-like osteophytes on the metacarpal heads; no osteopenia or erosions.

Which investigation would be most helpful in establishing the diagnosis?

An 83-year-old man with knee osteoarthritis (walking limited to <300 m) has minimal relief from paracetamol.

Examination shows varus deformity and a warm effusion indicating active intra-articular inflammation.

He is commenced on naproxen 500 mg twice daily. After 4 weeks there is no symptom improvement and his serum creatinine has risen from 140 µmol/L to 350 µmol/L [60–110].

In addition to ceasing naproxen, what is the most appropriate next step?

A 49-year-old woman presents with a 5-week history of symmetrical polyarthralgia of the hands and wrists, morning stiffness >1 hour, and occasional MCP swelling.

Examination shows synovitis of both wrists and PIP joints; skin is normal with no systemic features.

Investigations:

• ANA positive 1:80 speckled
• ENA negatives I don’t 
• Anti-dsDNA 7 IU/mL [<7]
• Anti-CCP (ACPA) positive
• Rheumatoid factor <20 IU/mL [<20].

What is the most likely diagnosis?

A 76-year-old woman presents with a 2-week history of a progressively swollen, painful left knee, now preventing walking, with no recalled injury.

Her background includes stage 3b chronic kidney disease (eGFR 32 mL/min/1.73m²), heart failure with preserved ejection fraction, and a history of peptic ulcer disease.

She is afebrile with a large left knee effusion and reduced range of movement.

X-ray shows chondrocalcinosis.

Joint aspiration yields cloudy fluid with a white cell count of 28,000/mm³ (predominantly neutrophils), no organisms on Gram stain, and positively birefringent rhomboid-shaped crystals under polarised light microscopy.

Which of the following is the most appropriate treatment?

A 68-year-old man presents with a 6-month history of insidious-onset, activity-related pain around his left lower limb, worse when rising from a chair and after prolonged walking.

He has noticed increasing difficulty putting on his shoes and socks. He denies any preceding trauma.

On examination he is afebrile with an antalgic gait. Passive internal rotation of the left hip reproduces his pain, and there is a reduced range of movement in flexion and internal rotation.

Straight leg raise is negative and neurological examination of the lower limbs is unremarkable.

X-ray of the pelvis shows joint space narrowing, subchondral sclerosis, and osteophyte formation at the left hip consistent with osteoarthritis.

In this patient, pain is most characteristically felt in which region?

Which clinical feature best differentiates inclusion body myositis from polymyositis?

A 60-year-old man with well-controlled diabetes and recurrent shoulder bursitis presents with 3 months of constant, dull, worsening lower back pain without trauma, fever or weight loss.

He is afebrile with markedly reduced spinal movement (painful thoracic lateral flexion) and thoracic-spine tenderness. Neurological examination is normal.

Investigations: FBE, ESR and CRP unremarkable (ESR <20 mm/hr, CRP <5 mg/L); HLA-B27 negative.

Radiographs show flowing ossification along the anterolateral aspect of at least four contiguous vertebral bodies with preserved disc spaces and no sacroiliitis.

Which of the following is the most appropriate initial management?

A 36-year-old woman presents with 1 month of dyspnoea, dry cough and a painful rash on the upper arms, without myalgia or weakness.

Oxygen saturation is 94% on room air with bibasal fine crackles. Skin shows erythematous plaques over the lateral upper arms (“sleeve sign”) and palmar papules/pustules (“inverse Gottron’s papules”), along with cutaneous ulceration over the finger joints.

Investigations:

• Strongly positive anti-MDA5 antibody
• Mildly elevated creatine kinase (CK 220 U/L, reference <170 U/L)
• Markedly elevated ferritin (2800 µg/L, reference 15–200 µg/L)
• HRCT shows diffuse reticular and nodular opacities with early ground-glass change
• PFTs show a restrictive defect with reduced DLCO
• Whole-body PET excludes occult malignancy.

Over the next week her oxygen requirement escalates despite commencement of high-dose corticosteroids.

Which of the following is the most appropriate next step in management?

Which is the most common pattern of joint involvement in psoriatic arthritis?

Identify the agent correctly matched with its molecular target in psoriatic arthritis:

• Ustekinumab – p40 subunit of IL-12/IL-23
• Guselkumab – TNF-alpha
• Upadacitinib – JAK-3 (monoclonal antibody)
• Etanercept – IL-17A
• Tofacitinib – IL-23 p19

A 45-year-old man presents with a 4-month history of pain and swelling affecting the distal interphalangeal joints of both hands, a swollen “sausage-shaped” second toe, and heel pain on walking.

He has a background of chronic scaly plaques over his extensor surfaces and scalp, and nail pitting.

Inflammatory markers are mildly elevated (CRP 18 mg/L, reference <5 mg/L) and rheumatoid factor and anti-CCP antibodies are negative.

Radiographs of the hands show erosive changes with some new bone formation at affected joints.

Which of the following is NOT recommended as standard therapy for his condition?