ABSTRACT
Hemolytic uremic syndrome (HUS) is associated with microthrombi ,mainly in the kidneys. It may be classified as typical HUS or atypical HUS (aHUS) .Majority of HUS occur in children (usually at 6 months of age), as a sequela of shigella infection. In aHUS, a genetic or sporadic insult causes dysfunction in the complement cascade, leading to complement deposition on endothelial cells, thickening of arterioles and capillaries, and endothelial swelling and detachment. Consequently, there is formation of obstructive thrombi in the vessel lumina and shearing of red blood cells, creating schistiocytes, that results in the triad of Coombs negative hemolytic anemia, renal impairment, and thrombocytopenia. We report a rare case of a 43-year-old black male who reacted to the 2nd booster dose (some 7 months after the 1st) of Astra Zeneca Covid-19 vaccine with aHUS. He had ophthalmoplegia, occipital headaches and suicidal ideation which all resolved on high dose oral prednisolone. The Astra Zeneca vaccine which uses a chimpanzee platform is the only one reported to have similar reactions and this is important to note and manage such potentially life threatening rare adverse event.