Urinary tract infection (UTI) facts. 1  Urinary tract infections (UTIs) are infections of the urethra, bladder, ureters, or the kidneys, which comprise the urinary tract.  E. coli bacteria cause the majority of UTIs, but many other bacteria, fungi, and parasites may also cause UTIs.
Common vasculitis skin lesions are: 1  red or purple dots (petechiae), usually most numerous on the legs. 2  larger spots, about the size of the end of a finger (purpura), some of which look like large bruises. 3  Less common vasculitis lesions are hives, an itchy lumpy rash and painful or tender lumps. Antibodies that react against cells in vessel walls. 2  In some cases of vasculitis, an antibody against the cytoplasm of neutrophils (anti-neutrophil cytoplasm antibodies, or ANCA) is the probable cause of the inflammation and damage.
Vasculitis can affect the small-or medium-sized vessels of the skin. Vasculitis affecting the small vessels of the skin (eg, arterioles, capillaries, postcapillary venules) tends to cause lesions such as purpura, petechiae, and possibly shallow ulcers.atients may present with skin symptoms such as lesions, including palpable purpura, petechiae, urticaria, ulcers, livedo reticularis, and nodules. If skin involvement is secondary to a systemic vasculitis, symptoms may also include fever, arthralgias, other organ involvement, or a combination.