Systemic diseases causing fever and rash

INTRODUCTION – AGENTS: The clinical picture of fever and rash may be caused by a variety of agents, including bacterial, viral, rickettsial, or fungal infections, immunocompromised states, autoimmune conditions, and other systemic diseases. Knowledge of the epidemiology, pathophysiology, clinical presentations, and management of these conditions is essential for the acute care physician, as some of these conditions have significant time-dependent morbidity and mortality. HISTORY AND PHYSICAL EXAMINATION: Crucial elements of the history and physical in the patient presenting with fever and rash are listed in Table 4.1. SYSTEMIC BACTERIAL INFECTIONS: Secondary Syphilis: Syphilis is caused by the spirochete Treponema pallidum, which typically enters the body through mucous membranes or nonintact skin (Table 4.2). Syphilis is the third most common reportable sexually transmitted disease in the United States (after chlamydia and gonorrhea) and is spread almost exclusively through sexual contact, with some rare cases of transplacental transmission. Syphilis affects all ethnicities equally but has a male predilection. The incubation period is 2–90 days from exposure. Primary syphilis presents as a painless genital chancre. (See Chapter 17, Ulcerative Sexually Transmitted Diseases.) Medical care is often delayed or not sought because the lesion is painless and usually resolves spontaneously though latent disease persists.