Board Review: Dermatology Lab Values and Monitoring

Overview / Definition Dermatology lab values and monitoring encompass a variety of laboratory tests used to evaluate skin conditions and systemic diseases that affect the skin. Understanding these values is crucial for appropriate diagnosis, treatment planning, and monitoring of patients. Epidemiology Many dermatological conditions have significant epidemiological data that can influence lab testing decisions. For instance, psoriasis and eczema are prevalent in varying populations, necessitating different approaches to laboratory evaluations. Psoriasis affects approximately 2-3% of the population. Atopic dermatitis has a prevalence of 10-20% in children. Incidence of skin cancers is increasing, with non-melanoma skin cancers being the most common. Pathophysiology / Mechanism The pathophysiology of dermatological disorders often involves complex immunological mechanisms, inflammatory pathways, and genetic predispositions. Laboratory tests can help elucidate these mechanisms, helping to confirm diagnoses and guide therapy. Psoriasis: Involves T-cell activation and inflammatory cytokine production. Atopic Dermatitis: Linked to impaired skin barrier function and allergic sensitization. Contact Dermatitis: Due to exposure to allergens or irritants, often requiring patch testing. Clinical Presentation Dermatological conditions can present with a spectrum of symptoms, often requiring laboratory tests for accurate diagnosis. Common clinical presentations include: Psoriasis: Red, scaly plaques; associated with arthritis. Atopic dermatitis: Pruritic, eczematous lesions; often in flexural areas. Contact dermatitis: Erythema, vesicles, and itching at sites of contact. Diagnosis / Workup Diagnosis often involves a combination of clinical evaluation and laboratory testing. Key tests may include: Complete Blood Count (CBC): To assess for signs of infection or systemic involvement. Basic Metabolic Panel (BMP): To check for electrolyte imbalances, particularly in severe skin conditi