Chapter 52: Disorders of Skin Integrity and Function

A central focus involves melanoma detection and risk stratification using the ABCDE framework, which guides clinical assessment of pigmented lesions through evaluation of asymmetrical morphology, irregular borders, chromatic heterogeneity, size exceeding six millimeters, and temporal evolution of the lesion. The chapter addresses the evolving classification of melanocytic nevi, explaining why dysplastic nevus categorization has become less prominent in contemporary dermatology due to evidence suggesting comparable malignant transformation risk between dysplastic and common variants. Acne vulgaris receives substantial coverage, including discussion of its underlying pathogenic mechanisms involving follicular obstruction, sebaceous gland hyperactivity, bacterial proliferation, and inflammatory cascade activation. Rosacea is examined as a distinct inflammatory disorder with dermatological manifestations and potential ocular complications that influence clinical management decisions. The chapter includes coverage of bacterial skin infections, with impetigo presented as a representative superficial infection affecting skin barrier function. Isotretinoin therapy is highlighted as a powerful pharmacological intervention for severe acne with significant clinical efficacy balanced against substantial adverse effect potential and strict regulatory monitoring requirements. Throughout the chapter, the interplay between structural skin components and disease pathogenesis underscores clinical decision-making, ranging from surveillance strategies for concerning pigmented lesions to therapeutic selection for inflammatory and infectious conditions affecting skin integrity.