The primary difference between Fibromuscular Dysplasia (FMD) and Segmental Arterial Mediolysis (SAM) lies in their typical presentation and symptom profile.
Key Differences in Presentation
Here's a breakdown of the differences:
| Feature | Fibromuscular Dysplasia (FMD) | Segmental Arterial Mediolysis (SAM) |
|---|---|---|
| Symptoms | Often asymptomatic; frequently presents with hypertension. | Commonly symptomatic at disease presentation; acute presentation is relatively common. |
| Symptom Onset | Insidious (slow and gradual). | Can be acute (sudden and severe). |
| Affected Arteries | Renal and carotid arteries are frequently affected. | Mesenteric arteries are often involved. |
| Symptomatic Rate | Most patients are relatively without symptoms. | 94% of patients have symptoms at presentation. |
Detailed Comparison
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Fibromuscular Dysplasia (FMD):
- Often identified during routine medical examinations due to other related conditions.
- Many individuals with FMD do not experience noticeable symptoms.
- Hypertension is a frequent finding, leading to the diagnosis.
- Affects medium-sized arteries, including the renal (kidney) and carotid (neck) arteries.
-
Segmental Arterial Mediolysis (SAM):
- Usually presents with clear symptoms, such as abdominal pain.
- Characterized by an acute and rapid onset.
- Most patients experience symptoms when diagnosed.
- Frequently involves the arteries supplying the intestines (mesenteric arteries).
In summary, while both FMD and SAM are vascular diseases, FMD is often silent and diagnosed because of hypertension, while SAM typically manifests with significant and acute symptoms, especially in the abdomen due to mesenteric artery involvement.
