II. Causes: Platelet Disorders
- See Thrombocytopenia Causes (Most common)
- See Platelet Dysfunction
III. Causes: Coagulation Factor Deficiency
IV. Causes: Vascular Factors
- Congenital
- Hereditary Hemorrhagic Telangiectasia
- Autosomal Dominant
- Fragile Telangiectasias of skin and mucus membranes
- Ehlers-Danlos Syndrome (Type IV)
- Skin hyperelasticity
- Joint Hypermobility
- Fragile skin and blood vessels
- Hereditary Hemorrhagic Telangiectasia
- Acquired: Infections
- Acquired: Medications
- Atropine
- Chloral Hydrate
- Long-term Corticosteroids
- Iodides
- Arsenicals
- Acquired: Trauma
- Violent coughing, Vomiting or Strangulation
- Petechiae in the head and neck (above the nipple line)
- Factitious Purpura (linear Petechiae)
- Religious rituals (e.g. Cupping or coining)
- Child Abuse (Nonaccidental Trauma)
- Psychogenic Purpura (Gardner-Diamond Syndrome)
- Violent coughing, Vomiting or Strangulation
- Acquired: Other