Page 621 - Concise Pathology for Exam Preparation ( PDFDrive )

606 SECTION II Diseases of Organ Systems

• Anucleate necrotic basal cells called colloid or Civatte bodies are seen in the papil-
lary dermis.
• There is epidermal hyperplasia, hypergranulosis and hyperkeratosis.
• Interface dermatitis (dense continuous band-like infiltrate of lymphocytes along
the dermoepidermal junction) is classically seen. The infiltrate may assume an angu-
lated zig-zag contour (saw toothing).
3. Lichen simplex chronicus (LSC)
• LSC is characterized by roughening and gradual thickening of skin called lichenifi-
cation (like lichen on a tree), due to repeated trauma or irritation (rubbing and
scratching).
• Sometimes the thickening may result in formation of nodules called prurigo
nodularis.
Morphology:
• Acanthosis, hyperkeratosis and hypergranulosis.
• Elongation of rete ridges, papillary dermal fibrosis and chronic dermal inflammatory
infiltrate.

Q. Write briefly on verrucae.

Ans. Verrucae are common lesions of children and adolescents but may be encountered at
any age.
• They are caused by low-risk types of human papilloma virus (HPV)
• Transmission is by direct contact and autoinoculation
• May regress spontaneously within 6 months to 2 years
• Verruca vulgaris is the most common type of wart (found frequently on dorsum of the
hands, and periungual areas, seen as grey-white to tan, flat to convex papules with a
pebble-like appearance).
• Verruca plana or flat wart is common on the face and dorsum of the hands, seen as
smooth tan macules.
• Verruca plantaris and palmaris occur on the soles and palms, respectively, and are
seen as rough, scaly lesions, 1–2 cm in diameter.
• Condyloma acuminatum occurs on the penis, female genitalia, urethra and perianal areas.
Morphology:
• Verrucous epidermal hyperplasia and papillomatosis
• Viral cytopathic effect (haloes surrounding the infected nuclei)
• Infected cells show prominent keratohyalin granules

Q. Write briefly on blistering or bullous disorders.

Ans. Group of disorders in which blisters are the primary and the most distinguished
feature:
1. Pemphigus
• Rare, autoimmune blistering disorder resulting from loss of normal intercellular
attachments
• Three major variants:
• Pemphigus vulgaris
• Pemphigus foliaceus
• Paraneoplastic pemphigus (pemphigus associated with internal malignancy)
Pathogenesis:
• Pemphigus vulgaris and foliaceus are caused by a type II hypersensitivity reaction
(antibody directed against a fixed-tissue antigen) and are linked to specific HLA
types.
• Patient’s sera contain pathogenic IgG antibodies to intercellular desmosomal proteins
(desmoglein Types I and III).
• Pemphigus vulgaris (most common type) involves mucosa and skin of scalp, face,
axillae, groin, trunk and points of pressure.
• Pemphigus foliaceus results in bullae confined to skin with infrequent involvement
of mucosa.

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