What is the purpose of the blood tests?
The purpose of the blood tests can be summarized as four-fold: diagnosis, monitoring of disease activity, monitoring the drug therapy used in treatment and looking for complications of lupus. Tests to help with diagnosis The diagnosis of lupus is complex and the process starts with the information provided by the patient to the doctor and the findings on examination. The blood tests are then used to confirm or refute the clinical suspicion of lupus, but they do not make the diagnosis by themselves. Clear criteria have been laid down to diagnose lupus, based on symptoms, signs and the results of blood tests, but all of these can change over time and in many cases, while the doctor may suspect lupus, the strict criteria may not be met. Normally four of the eleven criteria must be positive to make a diagnosis of lupus, but not necessarily simultaneously. Key features of the laboratory tests contained in the diagnostic criteria are the presence of protein in the urine and ‘casts’ which are
