Shigella associated hemolytic uremic syndrome is associated with all of the following except
|D||Renal micro thrombi|
Hemolytic Uremic Syndrome (HUS) is characterized by
1. Microangiopathic hemolytic anaemia (MAHA): intravascular hemolysis + red cell fragmentation.
1. Endothelial damage triggers thrombosis, platelet consumption and fibrin deposition, mainly in the renal microvasculature.
2. The strands cause mechanical destruction of passing red blood cells. Thrombocytopenia and ARF occur.
3. Cause 90% due to E coli 0157: produces a verotoxin which attacks endothelial cells.
4. This affects young children most, often occurring in outbreaks due to consumption of undercooked contaminated meat, with abdominal pain, bloody diarrhea and ARF.
Blood film: fragmented RBC platelets, Hb. Clotting tests are normal.
Treatment: No specific treatment, dialysis for ARF. There may be hematuria, proteinuria, which after resolved spontaneously. Dialysis for ARF may be needed. Plasma exchange is used in severe persistent disease.
Prognosis: Worse in non- E. Coli cases. Mortality 3-5%.