The skin can be the window to systemic diseases. The presenting cutaneous symptoms and signs will lead the clinician to a more focused differential diagnosis and thus aid in the ordering of laboratory tests. In some cases, for example, lymphoma, the skin biopsy is diagnostic.
Characterize the rash to limit the differential diagnosis
2.
Do laboratory tests based on the history and physical examination
A wide spectrum of diseases can present with fever and rash, including infections, drug reactions (e.g., DRESS; Fig 23.1 ), collagen vascular diseases, and vasculitis. These causes are listed in Table 23.1 , according to the primary cutaneous lesions: macules and papules, purpura, nodules and plaques, vesicles and bullae, and pustules. Some of these diseases (e.g., meningococcemia; Fig. 23.2 ) are life threatening and require prompt diagnosis and treatment.
Figure 23.1
DRESS – d rug r eaction with e osinophilia and s ystemic s ymptoms.
Table 23.1
Fever and Rash
Macules and papules (erythematous rashes)
●
Infections
●
Viral
Measles (rubella, rubeola)
Adenovirus
Echovirus
Infectious mononucleosis
Human immunodeficiency virus (HIV)
West Nile
Ebola
Chikungunya
Zika
●
Bacterial
Staphylococcus – toxic shock syndrome
Streptococcus – erysipelas, rheumatic and scarlet fever
Typhoid fever
Typhus – endemic
Rat-bite fever
●
Treponemal
Erythema migrans (Lyme disease)
Secondary syphilis
●
Fungal
Cryptococcosis
●
Drug reaction with eosinophilia and systemic symptoms (DRESS)
