Central Rashes

Central Rashes.

Etiology

Description

Measles

Paramyxovirus

Rubeola, first disease. Discrete lesions that become confluent as rash spreads from hairline downward, sparing palms and soles. Cough, conjunctivitis.

German measles

Togavirus

Rubella, third disease. Spreads from hairline downward, clearing as it spreads; Forchheimer spots. Adenopathy, arthritis.

Erythema infectiosum

parvovirus B19

Fifth disease. Bright-red "slapped-cheek" appearance ; diffuse lacy reticular rash that waxes and wanes over 3 weeks

Exanthem subitum

herpesvirus 6

Roseola, sixth disease. Diffuse maculopapular eruption (sparing face); resolves within 2 d

Infectious mononucleosis

Epstein-Barr virus

Diffuse maculopapular eruption; periorbital edema (50%); palatal petechiae (25%). Hepatosplenomegaly, pharyngitis, cervical lymphadenopathy, atypical lymphocytosis, heterophile antibody.

Impetigo

Rash on face with discrete vessicles that rupture and form yellow, honey colored crust.

Drug-induced eruption

Drugs

Intensely pruritic, bright-red macules and papules, symmetric on trunk and extremities; may become confluent

Rickettsial spotted fevers

Rickettsia

Eschar at site of bite; maculopapular eruption on proximal extremities, spreading to trunk and face

Lyme disease

Borrelia burgdorferi

Erythema chronicum migrans. Ixodes tick. Expanding "bull's eye" red rash with central clearing, concentric rings. Headache, myalgias, chills, photophobia occurring acutely; CNS disease, myocardial disease, arthritis.

Erythema marginatum

Group A Streptococcus

Rheumatic fever. Erythematous annular papules / plaques evolving / resolving within hours. Pharyngitis preceding polyarthritis, carditis, subcutaneous nodules.

SLE

Autoimmune disease

Macular and papular erythema, often in sun-exposed areas; discoid lupus lesions (local atrophy, scale, pigmentary changes); periungual telangilectasis; malar rash; vasculitis sometimes causing urticaria. Arthritis; cardiac, pulmonary, renal, hematologic, and vasculitic disease.

Pityriasis rosea

Acute solitary, oval, annular lesion of 2-6 cm on the trunk; followed weeks later by eruption of a christmas tree pattern of lesions.