Petechiae
Petechiae are millimeter-sized spots that appear on the skin as a result of capillary rupture.
Symptoms and Causes
Petechiae are small red, purple, or brown spots that appear on the skin due to rupture of capillaries (small blood vessels) located in intradermal or submucosal areas. As they are located beneath the skin, petechiae are flat.
Petechiae commonly cluster together, forming groups that resemble a rash, although they are not. The main differences are that petechiae are non-pruritic, non-painful, and do not blanch under pressure.
The prognosis of petechiae is variable, as it depends on the underlying cause. Although they may resolve spontaneously within a few days, they can also be a sign of a serious condition if they appear suddenly and are accompanied by other symptoms; therefore, medical evaluation is recommended.
Symptoms
The characteristic symptom of petechiae is the appearance of small reddish or purplish pinpoint spots on the skin, similar in size to a pinhead, which do not cause pain or itching. Although they can occur anywhere on the body, they are more commonly found on the face, neck, arms, and legs.
If the spots are accompanied by any of the following symptoms, this is a warning sign:
- Fever.
- Sudden onset of the lesions.
- Rapid progression.
- Unexplained bruising.
- Bleeding from the gums, nose, or mouth.
Causes
Petechiae form when a blood vessel ruptures and blood leaks into the skin. They may result from intense physical exertion, the use of certain medications (anticoagulants, antibiotics, anticonvulsants), or be a symptom of various conditions:
- Endocarditis: infection of the tissue lining the inside of the heart (endocardium).
- Cytomegalovirus infection: a viral disease of the Herpesviridae family.
- Streptococcal tonsillitis: bacterial throat infection.
- Hantavirus pulmonary syndrome: a viral infectious disease that causes respiratory distress.
- COVID-19: infectious disease caused by coronavirus.
- Mononucleosis: infection caused by the Epstein-Barr virus.
- Rubella: infectious disease caused by Rubivirus.
- Scarlet fever: bacterial infection caused by group A Streptococcus.
- Hemorrhagic fever: group of viral diseases (e.g., Ebola, dengue) affecting multiple organs and damaging blood vessels, leading to bleeding.
- Cryoglobulinemia: abnormal presence of cryoglobulins (abnormal antibodies) in the blood, increasing its viscosity.
- Thrombocytopenia: low platelet count.
- Scurvy: vitamin C deficiency.
- Vasculitis: inflammation of blood vessels due to an abnormal immune response.
- Leukemia: blood cancer originating in the bone marrow.
- Trauma.
- Bites or stings.
- Stress: intense emotional stress or prolonged crying may cause capillary rupture.
Risk factors
The risk of petechiae increases in the following situations:
- Age: aging makes the skin more prone to bruising due to increased fragility.
- Contact with animals.
- Living in areas with a high number of insects.
- Engaging in intense physical activity or sustained exertion.
- Not following a balanced diet.
- Having any of the conditions listed above.
Complications
Although petechiae are usually benign and do not cause health problems, they may occasionally lead to serious complications:
- Severe infections: meningitis, septicemia (an extreme immune response to infection).
- Excessive blood loss.
- Respiratory distress.
- Purpura: larger violet lesions than petechiae, ranging from 2 millimeters to 1 centimeter.
Which specialist treats petechiae?
Petechiae are typically managed within the specialty of Family and community medicine or Pediatrics. In severe cases, Medical-surgical dermatology and Venereology or Hematology and Hemotherapy may be involved.
Diagnosis
Petechiae are diagnosed through clinical observation, as they are easily recognized by a specialist. The evaluation typically includes:
- Assessment of the characteristics and distribution of the lesions.
- Pressure test to confirm absence of blanching.
- Evaluation of onset pattern and associated symptoms.
To determine the underlying cause, additional tests may be performed:
- Complete blood count: provides information on the patient’s overall health status and platelet count.
- Coagulation studies: assess various parameters:
- Prothrombin time: evaluates the intrinsic coagulation pathway, i.e., reactions initiated when blood is exposed to collagen after injury. It estimates the time required for plasma to clot.
- Partial thromboplastin time: evaluates the extrinsic coagulation pathway, the mechanism initiating hemostasis following vascular injury triggered by tissue factor. It determines clotting time.
- International normalized ratio: compares the patient’s clotting time with a standardized reference value.
- Bone marrow biopsy: a sample is obtained for laboratory analysis to detect hematologic disorders affecting blood cell production.
Treatment
Petechiae resolve spontaneously when benign or caused by mild conditions. To facilitate recovery, the following measures are recommended:
- Relative rest.
- Application of cold compresses to the affected area.
- Adequate hydration.
- Elevation of the affected limb, especially the legs, to improve circulation.
- Avoidance of medications without medical supervision.
When petechiae result from a more serious condition, treatment is directed at the underlying cause:
- Discontinuation or modification of pharmacological treatments.
- Administration of dietary supplements to correct vitamin deficiencies.
- Antibiotics for bacterial infections.
- Paracetamol or ibuprofen to reduce inflammation or fever.
- Immunostimulatory drugs.
- Platelet transfusion.
- In cases of leukemia: bone marrow transplantation, chemotherapy, targeted therapy, radiotherapy.
