What is the differential diagnosis of petechiae (small hemorrhagic spots)?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: April 7, 2025 • View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Petechiae Differential Diagnosis

The presence of petechiae, which are small, pinpoint spots on the skin that occur due to bleeding from small blood vessels, can be indicative of a variety of conditions. Here's a differential diagnosis organized into categories:

  • Single Most Likely Diagnosis
    • Idiopathic Thrombocytopenic Purpura (ITP): This condition is characterized by low platelet count due to immune-mediated destruction, leading to petechiae, purpura, and sometimes more severe bleeding. It's a common cause of petechiae, especially in children and young adults.
  • Other Likely Diagnoses
    • Viral Infections: Certain viral infections, such as influenza, mononucleosis, and HIV, can cause petechiae due to the body's immune response affecting platelet count or function.
    • Medication Side Effects: Some medications, including antibiotics, anticonvulsants, and nonsteroidal anti-inflammatory drugs (NSAIDs), can induce thrombocytopenia or affect platelet function, leading to petechiae.
    • Trauma: Physical trauma, including minor injuries, can cause petechiae, especially in areas of significant impact.
  • Do Not Miss Diagnoses
    • Meningococcemia: This is a life-threatening infection caused by Neisseria meningitidis, which can present with petechiae or purpura, along with fever, headache, and stiff neck. Early recognition and treatment are crucial.
    • Disseminated Intravascular Coagulation (DIC): A condition characterized by both widespread clotting and bleeding in the vascular system, which can be triggered by severe infections, trauma, or malignancies. Petechiae can be an early sign.
    • Leukemia: Certain types of leukemia, particularly acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML), can present with petechiae due to bone marrow failure affecting platelet production.
  • Rare Diagnoses
    • Henoch-Schönlein Purpura (HSP): A form of vasculitis that affects small blood vessels and is characterized by the deposition of immune complexes containing IgA antibodies. It typically presents with purpura, but petechiae can also occur.
    • Thrombotic Thrombocytopenic Purpura (TTP): A rare disorder of the blood-coagulation system, causing extensive microscopic thrombi to form in the smallest blood vessels throughout the body. It's characterized by thrombocytopenia, microangiopathic hemolytic anemia, renal failure, and neurological symptoms, with petechiae being a possible manifestation.
    • Ehlers-Danlos Syndrome: A group of genetic disorders that affect the body's connective tissue and can lead to easy bruising and petechiae due to fragile blood vessels.

Each of these conditions has distinct features and risk factors, and a thorough medical history, physical examination, and laboratory tests are essential for an accurate diagnosis.

Related Questions

What is the diagnosis for a 32-year-old woman, gravida (number of times pregnant) 3, para (number of viable births) 2, at 35 weeks gestation, presenting with frequent, painful uterine contractions, a history of shortened cervix, and currently 4 cm dilated and 90% effaced with the fetus at -3 station?
What are the treatment options for diverticulitis (inflammation of the diverticula) that is resistant to Cipro (ciprofloxacin) and Flagyl (metronidazole)?
What is the diagnosis for a 25-year-old woman, gravida (number of times pregnant) 2, para (number of viable births) 1, at 33 weeks gestation, presenting with intermittent contractions after intercourse, with a cervix 3 cm dilated and no evidence of rupture of membranes?
What is the diagnosis for a 24-year-old gravida 2 para 1 woman at 20 weeks gestation with a singleton fetus in breech presentation, a placenta edge 3 cm from the internal cervical os, and a shortened cervical length of 1.8 cm?
What is the diagnosis for a 40-year-old woman, gravida (number of times pregnant) 3, para (number of viable births) 2, at 33 weeks gestation, presenting with intermittent leakage of clear vaginal fluid, irregular contractions, and minimal amniotic fluid, with a history of type 2 diabetes mellitus and polyhydramnios (excess amniotic fluid)?
What is the best next step in managing this patient?

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.

Ask Question