Blood

```mermaid graph TD X[Medium Vessel diseases]

X -- young Adults - Chronic Hepatitis B --> X1["Polyarteritis Nodosa (PAN)\n***String of Pearls appearance***"]
X1 --> X1a[***Renal Artery***]
X1 --> X1b[Mesenteric Artery]
X1 --> X1c[Branches of Internal Carotid Arteries]
X1 --> X1d["***No Pulmonary Artery Involvement***"]

X1a --> X1a1[Renal ischemia ➡️ Hypertension]
X1b --> X1b1[Abdominal Pain and Blood in stools]
X1c --> X1c1[Neurological Symptoms]

X -- children <4years with Flu like symptoms --> X2[Kawasaki Disease]
X2 --> X2a["Damage medium arteries\n***M/C Coronary Vessels***\n➡️ Fibrinoid Necrosis\n➡️ Aneurysm\n➡️ Risk Of Thrombosis\n➡️ Myocardial Infarction at 4 year old Child"]
X2a -- treatment --> X2a1[Mostly Self-limiting\nRisk MI - Aspirin or IV Ig]
X2a -- Aspirin inhibit COX-1 COX-2 pathway --> X2aa["No TXA2"]
X2aa --> XXX[No platelet aggregation to form Thrombosis]

X -- Smokers --> X3[Buerger's Disease]
X3 -- Chemical of Cigarette injury --> X3a[Necrotizing Vasculitis of Digits and Toes]
X3a --> X3a1[Initial Raynaud Phenomenon with pain on exercise]
X3a1 --> X3a1a[Ulceration and gangrene and Auto-amputation]