Petechia

Petechia

Petechia and purpura on the low limb due to medication induced vasculitis.
ICD-10	R23.3
ICD-9	782.7
MeSH	D011693

A petechia ( /pɨˈtiːkiə/; plural petechiae /pɨˈtiːkɪ.iː/) is a small (1-2mm) red or purple spot on the body, caused by a minor hemorrhage (broken capillary blood vessels).

"Petechiae" refers to one of the three major classes of purpuric skin conditions. Purpuric eruptions are classified by size into three broad categories. Petechiae is generally used to refer to the smallest of the three classes of purpuric skin eruptions, those that measure less than 3 mm.

Causes

The most common cause of petechiae is through physical trauma such as a hard bout of coughing, vomiting or crying, which can result in facial petechiae, especially around the eyes. Petechiae in this instance are harmless and usually disappear within a few days. Petechiae may be a sign of thrombocytopenia (low platelet counts) when platelet function is inhibited (e.g., as a side effect of medications or during certain infections), or in clotting factor deficiencies. They may also occur when excessive pressure is applied to tissue (e.g., when a tourniquet is applied to an extremity or with excessive coughing or vomiting).

If unsure, petechiae should always be quickly investigated. They can be interpreted as vasculitis, an inflammation of the blood vessels, which requires immediate treatment to prevent permanent damage. Some malignancies can also cause petechiae to appear. Petechiae should be investigated by a doctor to rule out the more dangerous conditions. Dermatologists can be the most helpful specialists in these conditions because they can more easily identify if the condition is petechiae or some similar looking but less worrisome rash.

The significance of petechiae in children depends on the clinical context in which they arise. Petechiae in children can occur with viral infections. In this instance, they do not necessarily signify a serious illness. However, they are a hallmark signal of some potentially serious illnesses, such as meningococcemia, leukemia, and certain causes of thrombocytopenia, the first of which can cause death within 48 hours of infection. Therefore, their presence should not be ignored.

List of associated conditions

Infections

• Bolivian hemorrhagic fever
• Boutonneuse fever
• Cerebral malaria
• Congenital cytomegalovirus
• Congenital syphilis
• Crimean-Congo hemorrhagic fever
• Dengue fever
• Duke's disease
• Ebola
• Endocarditis
• H1N1
• Hanta virus
• Infectious mononucleosis
• Marburg virus
• Neisseria meningitidis
• Rocky mountain spotted fever
• Scarlet fever
• Typhus

Non-infectious conditions

• Hypocalcemia
• Idiopathic thrombocytopenic purpura
• Leukemia
• Celiac Disease
• Aplastic anaemia
• Scurvy
• Lupus
• Childhood protein-energy malnutrition such as Kwashiorkor or Marasmus
• Erythroblastosis fetalis
• Henoch-Schönlein purpura
• Kawasaki disease
• Schamberg's disease

Non-diseases

• Gua Sha, a Chinese treatment that scrapes the skin
• High-G training
• Hickey (injury)
• Asphyxiation (discussed below)

Causes of particular types

Palatal petechiae.

Petechiae on the soft palate are mainly associated with streptococcal pharyngitis, and as such it is an uncommon but highly specific finding. 10 to 30 percent of palatal petechiae cases are estimated to be caused by suction such as can be habitual or secondary to fellatio.

Facial petechiae, especially around the eyes, indicate physical trauma such as by hard bouts of coughing, vomiting or crying.

Forensics

Petechiae on the face and conjunctiva (eyes) can be a sign of a death by asphyxiation. Petechiae are thought to result from an increase of pressure in the veins of the head and hypoxic damage to endothelia of blood vessels.

Petechiae can be used by police investigators in determining if strangulation has been part of an attack. The documentation of the presence of petechiae on a victim can help police investigators prove the case. Petechiae resulting from strangulation can be relatively tiny and light in color to very bright and pronounced. Petechiae may be seen on the face, in the whites of the eyes or on the inside of the eyelids.

See also

• Purpura
• Ecchymoses