Renal
A 6-year-old develops facial oedema and 3+ proteinuria.
Diagnosis? Common cause in children?
Nephrotic syndrome due to minimal change disease.
A 15-year-old boy has a painful, enlarging mass around the distal femur metaphysis.
Most likely diagnosis?
Osteosarcoma (MC primary malignant bone tumour; metaphysis of long bones; adolescents)
A 58-year-old man has Hb 95 g/L, MCV 72 fL, ↓ferritin, ↑TIBC.
Diagnosis and key cause to exclude?
Iron deficiency anaemia — exclude GI blood loss/malignancy.
A 72-year-old man presents with a slow-growing, pearly nodule with rolled edges and surface telangiectasia on his right cheek. The lesion bleeds easily when shaved.
What is the most likely diagnosis and its most common causative mutation?
Basal cell carcinoma (BCC); mutation in the PTCH1 tumour suppressor gene (Hedgehog pathway).
A collapse lasts 15 seconds with rapid recovery and no post-ictal confusion. There were brief multifocal jerks.
Most likely diagnosis? One key distinguishing feature from epileptic seizure.
Syncope; rapid recovery without post-ictal confusion (seizures typically have post-ictal phase).
A 22-year-old has macroscopic haematuria following a sore throat.
Likely diagnosis and classic biopsy finding?
IgA nephropathy; mesangial IgA deposition on immunofluorescence.
A 65-year-old woman presents with low-trauma vertebral compression fractures. DXA scan shows a T-score of –2.8.
a) What is the diagnosis?
b) Name two major risk factors for this condition.
a) Osteoporosis
b) Age/postmenopausal oestrogen deficiency, glucocorticoid use, low BMI, smoking, sedentary lifestyle, or family history.Osteogenesis imperfecta (type I collagen mutation)
Which pattern fits anaemia of chronic disease?
A. ↓Fe, ↑TIBC, ↓ferritin
B. ↓Fe, ↓TIBC, ↑ferritin
C. ↑Fe, ↓TIBC, ↑ferritin
B. (Low Fe and TIBC, ferritin normal/high due to ↑hepcidin.)
A 68-year-old farmer develops a non-healing hyperkeratotic plaque with central ulceration on his forearm. Biopsy shows atypical keratinocytes invading the dermis with keratin pearls.
What is the diagnosis, and name two high-risk features for recurrence or metastasis.The presence of keratin pearls and intercellular bridges on histology is characteristic of this malignant tumour of epidermal keratinocytes.
Diagnosis: Cutaneous squamous cell carcinoma (SCC)
High-risk features: poor differentiation, deep invasion, perineural or vascular invasion, margin involvement, immunosuppression.
A 24-year-old has episodes of rising epigastric aura, lip-smacking automatisms, and impaired awareness; some progress to GTCS.
a) Seizure type? b) Best single imaging test and classic finding?
a) Focal (temporal lobe) seizures with secondary generalisation.
b) MRI brain; mesial temporal (hippocampal) sclerosis.
A septic elderly patient develops muddy brown casts in urine.
Diagnosis and main underlying mechanism?
Acute tubular necrosis due to ischaemia or nephrotoxins.
A 10-year-old boy develops painful swelling in the metaphysis of the femur. Imaging shows lytic lesions with surrounding sclerosis, and histology reveals Staphylococcus aureus.
a) What is the diagnosis?
b) Define sequestrum and involucrum in this context.
a) Pyogenic osteomyelitis
b) Sequestrum = fragment of dead necrotic bone separated from viable tissue.
Involucrum = new bone sheath formed around the sequestrum.
A woman with autoimmune gastritis has macro-ovalocytes and hypersegmented neutrophils.
Diagnosis and confirmatory test?
Pernicious anaemia — check anti-intrinsic-factor antibodies or serum B12.
A 36-year-old woman notices a dark irregular mole on her back that has recently enlarged and started to bleed.
List the ABCDE criteria for melanoma diagnosis and identify the single most important histopathological prognostic factor.
Asymmetry
Border irregularity
Colour variation
Diameter >6 mm
Evolving lesion
Most important prognostic factor: Breslow thickness.
A teenager with idiopathic generalised epilepsy has myoclonic jerks on waking and GTCS.
First-line broad-spectrum ASM? One important caveat
Valproate; avoid/limit in women of childbearing potential due to teratogenicity (use lamotrigine/levetiracetam instead).
A patient with anti-GBM antibodies presents with haematuria and haemoptysis.
Diagnosis and key treatment?
Goodpasture syndrome; treat with plasmapheresis + steroids + cyclophosphamide.
A 7-year-old presents with short limbs and normal-sized head and trunk. Genetic testing reveals a gain-of-function mutation in FGFR3.
a) What is the diagnosis?
b) Explain the underlying mechanism of bone growth failure.
a) Achondroplasia
b) FGFR3 mutation → inhibits chondrocyte proliferation in growth plates → decreased endochondral ossification → impaired longitudinal bone growth (short limbs).
A patient with jaundice, ↑retics, ↑LDH, ↓haptoglobin, spherocytes on film.
Type of anaemia and mechanism?
Extravascular haemolytic anaemia from membrane or autoimmune destruction.
A biopsy from a rapidly enlarging pigmented lesion shows atypical melanocytes with pagetoid spread and a BRAF V600E mutation.
Explain the significance of this mutation and name a class of drugs targeting it.
The BRAF V600E mutation activates the MAP-kinase pathway → uncontrolled cell proliferation.
Targeted drugs: BRAF inhibitors (e.g. vemurafenib, dabrafenib) ± MEK inhibitors (trametinib).
Define status epilepticus and state the first-line drug class used initially.
Continuous or recurrent seizures >5 minutes without recovery.
First-line: Benzodiazepines (e.g., IV diazepam / midazolam).
ABG: pH 7.28, HCO₃⁻ 14 mmol/L, pCO₂ 30 mmHg.
a) Primary disorder? b) Use Winter’s formula to assess compensation.
a) Metabolic acidosis.
b) Expected pCO₂ = 1.5(14) + 8 ± 2 = 29 ± 2 → measured 30 → appropriate respiratory compensation.
Compare Paget’s disease and osteosarcoma in terms of cause and key features.
Paget’s: Excessive bone turnover → disorganised “mosaic” bone, ↑ALP, deformity, risk of transformation to osteosarcoma.
Osteosarcoma: Malignant osteoblasts forming osteoid; metaphyseal long bones; “sunburst” on X-ray, aggressive with lung mets.
A 67-year-old with bone pain, anaemia, renal failure, and lytic lesions.
Diagnosis and main mechanism of bone disease?
Multiple myeloma — ↑RANKL/IL-6 → osteoclast activation and bone resorption.
A 23-year-old with severe peanut allergy develops hypotension, bronchospasm, and urticaria within minutes of exposure.
Explain the immunopathogenesis of this reaction, including the key cytokines involved in sensitisation and effector phases.
Sensitisation: Allergen exposure → Th2 activation → IL-4, IL-13 induce B-cell class switch to IgE → binds FcεRI on mast cells/basophils.
Re-exposure: Allergen cross-links IgE → mast cell degranulation → histamine, leukotrienes, prostaglandins cause vasodilation, oedema, bronchospasm.
Late phase: cytokine release; IL-5 recruits eosinophils → sustained inflammation.
A 29-year-old with drug-resistant temporal lobe epilepsy from mesial temporal sclerosis has failed two appropriate ASMs.
Next best definitive management option? Two counselling points for safety/legalities.
Refer for epilepsy surgery evaluation (e.g., anterior temporal resection).
Counselling: no driving ≥6 months after a seizure (Austroads); avoid swimming alone/heights/machinery and provide seizure first-aid advice.