Page 250 - Concise Pathology for Exam Preparation ( PDFDrive )

10 Blood Vessels 235

Clinical Features

• Usually affects adult males, in the 5th decade; multiple organ involvement may be
seen.
• Clinical manifestations include:
• Persistent pneumonitis with bilateral infiltrates in the lungs
• Chronic sinusitis and nasopharyngeal ulceration
• Chronic renal disease, skin rashes, muscle pain and articular involvement
• Wegener granulomatosis without renal involvement is labelled ‘limited form’ of the
disease.
• Untreated, 80% of the patients die within a year.

Microscopy

• Necrotizing vasculitis (segmental or circumferential) of small and sometimes large vessels
• Granulomatous inflammation with geographic pattern of necrosis with extensive
infiltration by neutrophils, mononuclear cells, epithelioid cells, multinucleate giant
cells and fibroblasts
• Dispersed granulomas may coalesce to form nodules that undergo cavitation
• Renal lesions may be focal or diffuse, namely, focal necrotizing (acute focal prolif-
eration and necrosis in the glomeruli with thrombosis) and diffuse crescentic
glomerulonephritis

Q. Write briefly about Raynaud phenomenon.

Ans. Raynaud phenomenon is not a true vasculitis, but a functional vasospastic
disorder chiefly affecting small arteries and arterioles of the extremities of young
healthy females.
• Clinically, it presents with pallor, redness and cyanosis of the digits and tips of nose
or ears.
• Cause is not known; it is thought to be due to vasoconstriction mediated by autonomic
stimulation of the affected vessels.
• Ischaemic effect is provoked by cold (emotions, trauma, hormones and drugs also play
a role).
• No pathological change is observed in vessel wall except mild intimal thickening later
in the course of the disease.
• Raynaud phenomenon can be primary or secondary. The latter occurs due to an underlying
cause, eg, atherosclerosis, connective tissue disease, multiple myeloma and Buerger disease.
Primary Raynaud phenomenon differs from secondary Raynaud phenomenon in having
symmetrical involvement of the extremities.

Q. Write briefly about Buerger disease.
Ans. Also called thromboangiitis obliterans; it is characterized by acute and chronic, segmental,
thrombosing, inflammatory involvement of the small- and medium-sized arteries and veins of
extremities.
• Usually affects men younger than 35 years, particularly the heavy smokers.
• Intermittent claudication due to ischaemia manifests as intense pain in the limbs.
• Fibrous tissue cuffs may form around arteries, veins and nerves leading to
gangrene.

Aetiopathogenesis
• Heavy cigarette smoking directly damages endothelium leading to hypercoagulability
and thrombosis.
• An immune response to some constituents of tobacco smoke has also been implicated.
• Familial occurrence, ethnic distribution and HLA association point to a possible genetic
basis.

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