Bacterial Diseases

Bacterial infections commonly affect the skin and account for ~20% of outpatient dermatology visits. Staphylococci and streptococci cause the majority of bacterial skin conditions, which range from common infections such as impetigo and cellulitis to severe multisystem disorders such as toxic shock syndrome. Other Gram-positive and Gram-negative bacterial infections have a wide variety of localized and widespread cutaneous manifestations. In some patients, such skin findings represent signs of a systemic bacterial infection or underlying immunodeficiency. This chapter also reviews several spirochetal infections, actinomycosis, and nocardiosis.