Histologic Diagnosis of Inflammatory Skin Diseases

Leukocytoclastic vasculitis

…self clinically in manifold ways. For example, it may begin as urticarial papules devoid of even a trace of purpura and it may remain urticarial until lesions disappear. More often, however, papules of leukocytoclastic vasculitis soon become purpuric…

Differential Diagnosis in Dermatopathology

Leukocytoclastic vasculitis vs. livedo vasculitis

An inflammatory process that consists of transient, slightly erythematous, edematous papules and plaques characterized by a pseudopod-like border. They may be of either allergic or non-allergic cause, among the former being ingestants, injectants, i…

Histologic Diagnosis of Inflammatory Skin Diseases

The Algorithmic Method

…#8221; of the infundibulum has been breached (see Fig. 5.313), urtica, and erysipelas. When eosinophils predominate in the interstitium, the leading cause is the “bite” of an insect, but other possibilities range from pruritic urticarial…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…edematous papillary dermis = Bullous pemphigoid, vesicular An urticarial lesion of bullous pemphigoid often is affiliated with eosinophils in the epidermis, where they induce spongiosis. Some urticarial lesions of bullous pemphigoid are associated w…

Differential Diagnosis in Dermatopathology

Discussions

…widespread or confined to a single anatomic site. They may be urticarial and without even a hint of purpura, or they may be strikingly hemorrhagic. So-called urticarial vasculitis is merely leukocytoclastic vasculitis devoid of purpura. Perhaps the…

Histologic Diagnosis of Inflammatory Skin Diseases

Identification of Basic Patterns: Skin: Vasculitis

…nonetheless. The finding of nuclear “dust” enables urticarial lesions of leukocytoclastic vasculitis to be distinguished from true urtica in which no “dust” of nuclei of neutrophils occurs. In some cases of infection by herpes…

Histologic Diagnosis of Inflammatory Skin Diseases

Bullous pemphigoid

…of lesions Arcuate, annular, and serpiginous when lesions are urticarial especially Arrangement of lesions Scattered and discrete, but becoming confluent in time Individual lesions Urticarial papules and plaques early, vesicles and bullae later, an…

Histologic Diagnosis of Inflammatory Skin Diseases

Limitations of the Algorithmic Method

The algorithmic method proposed in these pages and predicated on patterns histopathologic is intended to be more than just a guide to diagnosis of particular pathologic processes in skin and subcutaneous fat; it is meant to serve as a springboard fo…

Differential Diagnosis in Dermatopathology

Urticaria vs. Urticarial lesions of bullous pemphigoid

An inflammatory process that consists of transient, slightly erythematous, edematous papules and plaques characterized by a pseudopod-like border. They may be of either allergic or non-allergic cause, among the former being ingestants, injectants, i…