Clinical manifestations and pathophysiologic mechanisms of systemic lupus erythematosus. Why is this disease so difficult to diagnose? Which labs are commonly run? {Ans: Manifestations: arthralgias or arthritis, vasculitis and rash, renal disease, hematologic abnormalities (anemia), cardiovascular disease Labs: diagnosis usually made on positive ANA (98% with SLE are positive); positive testing for more specific tests usually follows (antibodies against Sm, dsDNA) Pathophysiologic mechanisms: multiple immune disorders that result in production of large variety of autoantibodies against nucleic acid, erythrocytes, coagulation proteins, phospholipids, lymphocytes, platelets Difficult to diagnose due to S&S affecting almost every body system and them tend to be intermittent}What are empirical risks and how do they affect disease? {Ans: Empirical risks are risks based on direct observation}What are the 3 layers of human defense? What happens during each? {Ans: Physical- protect against damage and infection are composed of tightly associated epithelial cells including those of the skin and of the membranous sheets lining the gastrointestinal, genitourinary, and respiratory tracts. Mechanical- "washing" the surfaces (sloughing off of dead skin, vomiting, urination, coughing). Biochemical barriers- secrets substances meant to trap of destroy microorganisms. (Mucus, sweat, saliva, tears, sebaceous glands, and earwax).}Why is a vaccination safer than suffering