Page 97 - Textbook of Pathology, 6th Edition

1. Skin changes. Skin is involved diffusely, beginning are considered to bring about inflammatory destruction of 81
distally from fingers and extending proximally to arms, muscle. Viral etiology due to infection with coxsackie B virus
shoulders, neck and face. In advanced stage, the fingers has also been suggested.
become claw-like and face mask-like. MORPHOLOGIC FEATURES. The skeletal muscles
Microscopically, changes are progressive from early to usually affected are of pelvis, shoulders, neck, chest and
late stage. diaphragm. CHAPTER 4
Early stage shows oedema and degeneration of Histologically, vacuolisation and fragmentation of muscle
collagen. The small-sized blood vessels are occluded and fibres and numerous inflammatory cells are present. In
there is perivascular infiltrate of mononuclear cells. late stage, muscle fibres are replaced by fat and fibrous
Late stage reveals thin and flat epidermis. Dermis is tissue.
largely replaced by compact collagen and there is hyaline
thickening of walls of dermal blood vessels. In advanced CLINICAL FEATURES. It is a multi-system disease
cases subcutaneous calcification may occur. characterised by:
2. Kidney changes. Involvement of kidneys is seen in muscle weakness, mainly proximal;
majority of cases of systemic sclerosis. The lesions are skin rash, typically with heliotropic erythema and
prominent in the walls of interlobular arteries which periorbital oedema;
develop changes resembling malignant hypertension. dysphagia due to involvement of pharyngeal muscles;
There is thickening of tunica intima due to concentric respiratory dysfunction; and
proliferation of intimal cells and fibrinoid necrosis of association with deep-seated malignancies.
vessel wall. Immunopathology Including Amyloidosis
3. Smooth muscle of GIT. Muscularis of the alimentary Sjögren’s Syndrome
tract, particularly oesophagus, is progressively atrophied Sjögren’s syndrome is characterised by the triad of dry eyes
and replaced by fibrous tissue. (keratoconjunctivitis sicca), dry mouth (xerostomia), and
4. Skeletal muscle. The interstitium of skeletal muscle rheumatoid arthritis. The combination of the former two
shows progressive fibrosis and degeneration of muscle symptoms is called sicca syndrome.
fibres with associated inflammatory changes.
5. Cardiac muscle. Involvement of interstitium of the ETIOPATHOGENESIS. Immune mechanisms have been
heart may result in heart failure. implicated in the etiopathogenesis of lesions in Sjögren’s
syndrome. Antinuclear antibodies are found in about 90%
6. Lungs. Diffuse fibrosis may lead to contraction of the of cases; test for rheumatoid factor is positive in 25% of cases.
lung substance. There may be epithelium-lined honey- The lesions in lacrimal and salivary glands are mediated by
combed cysts of bronchioles. T lymphocytes, B cells and plasma cells.
7. Small arteries. The lesions in small arteries show
endarteritis due to intimal proliferation and may be the MORPHOLOGIC FEATURES. In early stage, the lacrimal
cause for Raynaud’s phenomenon. and salivary glands show periductal infiltration by
lymphocytes and plasma cells, which at times may form
CLINICAL FEATURES. Systemic sclerosis is more common lymphoid follicles (pseudolymphoma). In late stage,
in middle-aged women. The clinical manifestations include: glandular parenchyma is replaced by fat and fibrous
claw-like flexion deformity of hands; tissue. The ducts are also fibrosed and hyalinised.
Raynaud’s phenomenon;
oesophageal fibrosis causing dysphagia and CLINICAL FEATURES. The disease is common in women
hypomotility; in 4th to 6th decades of life. It is clinically characterised by:
malabsorption syndrome; Symptoms referable to eyes such as blurred vision, burning
respiratory distress; and itching.
malignant hypertension; Symptoms referable to xerostomia such as fissured oral
pulmonary hypertension; and mucosa, dryness, and difficulty in swallowing.
biliary cirrhosis. Symptoms due to glandular involvement such as enlar-
ged and inflamed lacrimal gland (Mikulicz’s syndrome is
Polymyositis-Dermatomyositis involvement of parotid alongwith lacrimal gland).
Symptoms due to systemic involvement referable to lungs,
As the name suggests, this disease is a combination of CNS and skin.
symmetric muscle weakness and skin rash.
Reiter’s Syndrome
ETIOPATHOGENESIS. The exact cause of the disease is
unknown. However, antinuclear antibodies are detected in This syndrome is characterised by triad of arthritis,
25% of cases. Thus, an immunologic hypothesis has been conjunctivitis and urethritis. There may be mucocutaneous
proposed. The affected muscles are infiltrated by sensitised lesions on palms, soles, oral mucosa and genitalia.
T lymphocytes of both T helper and T suppressor type which Antinuclear antibodies and RA factor are usually negative.