MLT GlobeBasic Pathology: Systemic pathology
10 Basic Pathology MCQs on Systemic pathology with answers and explanations.
An elderly woman with bone metastases breaks her femur while turning in bed. This is best termed a:
A pathological fracture occurs through bone weakened by existing disease (tumour, osteoporosis) with minimal trauma. Stress fractures follow repeated loading of normal bone.
A pathologist distinguishes atherosclerosis from other forms of arterial hardening. Which feature is specific to atherosclerosis?
Arteriosclerosis is any arterial hardening; atherosclerosis is the subtype defined by lipid-laden intimal plaques. Stiffening, age and hypertension are shared by both.
Dilated, tortuous superficial leg veins most often develop because of:
Incompetent valves allow blood to pool and reflux, stretching superficial veins into varicosities. Thrombosis may complicate varicose veins but is not the usual primary cause.
A child has heavy proteinuria, hypoalbuminemia and generalized edema due to leaky glomerular capillaries. The most likely diagnosis is:
Nephrotic syndrome causes loss of albumin in urine, reducing plasma oncotic pressure and producing generalized edema.
In nephrotic syndrome, which plasma protein is lost in the largest amount in urine?
Albumin is small and abundant, so it leaks most readily through damaged glomeruli. Large proteins such as IgM and alpha-2 macroglobulin are retained.
In which joint disorder is a raised serum uric acid most characteristic?
Gout results from urate crystal deposition, usually with hyperuricaemia; synovial fluid shows negatively birefringent needle crystals.
Synovial fluid from an acutely painful big toe shows needle-shaped, negatively birefringent crystals under polarised light. These crystals are:
Gout is caused by deposition of monosodium urate crystals, which are needle-shaped and strongly negatively birefringent. Calcium pyrophosphate crystals (pseudogout) are rhomboid and weakly positive.
Rupture of a berry aneurysm in the circle of Willis most commonly causes a(n):
Berry aneurysms sit on arteries in the subarachnoid space, so rupture bleeds there, typically giving a sudden severe headache. Xanthochromia in CSF supports the diagnosis.
A painless scrotal swelling transilluminates brightly because fluid has collected in the tunica vaginalis. This is a:
A hydrocele is fluid around the testis in the tunica vaginalis and lets light through. Solid tumours do not transilluminate; a varicocele is dilated veins.
Barium swallow shows a dilated oesophagus with a smooth 'bird's beak' narrowing, because the lower sphincter fails to relax. This is:
Loss of inhibitory myenteric neurones stops the lower oesophageal sphincter relaxing and abolishes peristalsis, producing achalasia.