Petechiae

Petechiae

TL;DR Petechiae are pinpoint (1-2mm), non-blanching red or purple spots on skin or mucous membranes as a results of small capillary bleeding. Causes ▾: Increased pressure (coughing, straining). Low platelet count (thrombocytopenia). Platelet dysfunction. Infections...
Ecchymoses

Ecchymoses

TL;DR Ecchymoses are subcutaneous bleeding causing skin discoloration (bruise). Pathophysiology ▾: Small vessel damage leads to blood leakage into tissues; hemoglobin breakdown causes color changes. Causes ▾: Trauma, hematologic disorders, vascular issues,...
Henoch-Schönlein Purpura (HSP)

Henoch-Schönlein Purpura (HSP)

TL;DR Henoch-Schönlein Purpura (HSP) is a systemic small-vessel vasculitis characterized by palpable purpura, arthritis/arthralgia, abdominal pain, and often kidney involvement. Causes ▾: Exact cause unknown; likely triggered by infections (e.g., upper respiratory),...