Noticing “purple spots on skin photos“ can be unsettling. These spots, medically known as purpura, occur when small blood vessels leak under the skin. They range from small dots (petechiae) to large patches (ecchymosis). While often just a bruise, they can sometimes indicate a low platelet count or a vascular issue. If the spots are raised, painful, or appear alongside a fever, it is important to consult a healthcare provider promptly to rule out more serious conditions.
Here’s a practical visual guide and breakdown to help you identify what you might be seeing.
Types of Purple Spots: A Quick Visual Guide
| Name | Size | Appearance | Blanches When Pressed? |
| Bruise (Ecchymosis) | Variable | Blue-purple, fades to yellow-green | Yes |
| Petechiae | Tiny (< 2mm) | Pinpoint red-purple dots | No |
| Purpura | 2mm – 1cm | Purple patches, flat | No |
| Ecchymosis | > 1cm | Large purple/black area | No |
| Actinic Purpura | Variable | On sun-damaged, thin skin – arms mainly | No |
| Vasculitis rash | Variable | Raised, palpable purple spots | No |
The blanch test is important: press a glass or your finger firmly on the spot. If it turns white, blood is moving (likely a benign vascular cause). If it does NOT blanch, blood has leaked outside blood vessels – this warrants medical evaluation, especially in children.
Common Causes of Purple Spots
1. Bruising
The most common cause. Blood leaks into tissue after an injury. Most bruises resolve within 1-2 weeks, progressing from purple/blue to green to yellow. Easy or unexplained bruising can sometimes indicate a blood clotting issue.
2. Petechiae
Tiny, pinpoint purple-red dots that appear in clusters. They’re caused by minor bleeding under the skin and can result from:
- Intense straining (coughing, vomiting, crying hard)
- Physical trauma
- Infections like strep throat, endocarditis, or COVID-19
- Low platelet count (thrombocytopenia)
- Certain medications like blood thinners or aspirin
Petechiae that appear without an obvious explanation, especially in children or accompanied by fever, need urgent medical review.
3. Purpura
Larger than petechiae, purpura are purple patches that don’t blanch. They indicate blood leaking from vessels and are associated with:
- Autoimmune conditions like ITP (immune thrombocytopenic purpura) or Henoch-Schonlein purpura
- Blood vessel inflammation (vasculitis)
- Viral or bacterial infections
- Medication reactions
4. Actinic (Solar) Purpura
Common in older adults, these purple spots appear on forearms and the backs of hands. They result from decades of sun exposure thinning the skin and weakening blood vessels. They’re generally harmless but can look dramatic. The spots resolve without treatment in 1-3 weeks.
5. Age-Related Bruising
As we age, skin becomes thinner, fat tissue under the skin decreases, and blood vessels become more fragile. This makes bruising from very minor impacts much more common – even without remembering the bump that caused it.
When to See a Doctor Immediately
These situations require prompt or emergency medical attention:
- Purple spots that appear suddenly with no injury and don’t blanch
- Spots accompanied by fever, stiff neck, or feeling very unwell – may indicate meningococcal disease
- Rapid spread of purple spots over hours
- Spots with unusual pain, warmth, or swelling
- Easy bruising alongside heavy periods, frequent nosebleeds, or bleeding gums
What Will a Doctor Do?
Depending on what they observe, a doctor may order:
- Complete blood count (CBC) to check platelet levels
- Coagulation studies to evaluate clotting
- Blood cultures if infection is suspected
- Skin biopsy if vasculitis is a concern
The Bottom Line
Purple spots on skin have a wide range of causes – from completely harmless to medically urgent. The non-blanching test is your most useful immediate tool. A single bruise or patch of actinic purpura in an older adult is typically nothing to worry about. But multiple unexplained spots, especially in children or with other symptoms, should be evaluated the same day. When in doubt, it is always better to get it checked.
