Connective Tissue Diseases
Cutaneous manifestations of connective tissue diseases are important to identify because they can be a clue to an undiagnosed systemic autoimmune disease. Many lesions, such as those seen in systemic…
Nutritional Diseases
A deficiency or excess of certain required vitamins or minerals can cause specific findings in the skin, hair, nails, and mucosae. This chapter provides images of many of these findings,…
Diseases of Subcutaneous Fat
Panniculitis presents with deep erythematous nodules, induration, and tenderness. Clinical lesions of erythema nodosum can appear as deep-seated, erythematous, tender nodules or can resemble bruises, giving rise to the term…
Seborrheic Dermatitis, Psoriasis, Recalcitrant Palmoplantar Eruptions, Pustular Dermatitis, and Erythroderma
The primary lesion of a papulosquamous disorder is a papule with scale, but because patients often present later in the course of disease, the primary lesions may not be visible,…
Erythema and Urticaria
A wide variety of conditions can present with erythema or urticarial lesions. Whereas many conditions such as urticaria and angioedema lack identifiable surface changes, other diagnoses in this chapter have…
Syphilis, Yaws, Bejel, and Pinta
Syphilis has been dubbed “the great imitator” for its ability to assume varied morphologies. Primary syphilis is characterized by a chancre—a minimally tender, indurated ulcer—or less commonly by syphilitic balanoposthitis….
Hansen Disease
Clinical manifestations of leprosy vary from the subtle hypopigmented patches of indeterminate leprosy to the diffuse facial infiltration and nodules of lepromatous leprosy. The clinical and histologic manifestations of the…
Pityriasis Rosea, Pityriasis Rubra Pilaris, and Other Papulosquamous and Hyperkeratotic Diseases
Pityriasis rosea presents with erythematous macules that develop a delicate central silver scale. As the lesions evolve, they assume an oval configuration often best observed on the back and flanks….
Mycobacterial Diseases
Tuberculosis and atypical mycobacterial infections can be difficult to diagnose clinically and require a high index of suspicion and familiarity with their manifestations in the skin. Tuberculosis (TB) is more…
