Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
Petechial rash is a small, pinpoint, red or purple spot caused by bleeding into the skin. It can be indicative of serious infections, including bacterial infections of the circulatory and nervous systems.
5 Must Know Facts For Your Next Test
Petechial rash often indicates capillary hemorrhage and can be a sign of severe conditions like meningitis or endocarditis.
It is commonly associated with Neisseria meningitidis infections in the context of bacterial diseases of the nervous system.
A petechial rash does not blanch (turn white) when pressure is applied, differentiating it from other types of rashes.
Infections leading to petechial rash may progress rapidly and require immediate medical attention.
Diagnosis typically involves blood cultures, lumbar puncture, and other tests to identify the underlying bacterial pathogen.