The results are published in the November 2004 issue of Arthritis & Rheumatism.
"This is the first report of abnormal levels of the protein erythrocyte-C4d in human disease," said lead author Susan Manzi, M.D., M.P.H., associate professor of medicine, epidemiology and dermatology at the University of Pittsburgh School of Medicine and the University of Pittsburgh Graduate School of Public Health. "Abnormally high levels of erythrocyte-C4d and low levels of erythrocyte-CR1 are characteristic of SLE and combined measurement of the two proteins has high diagnostic sensitivity and specificity for lupus."
The significance of the finding is substantial, according to Joseph Ahearn, M.D., associate professor of medicine at the University of Pittsburgh School of Medicine and senior author of the study.
"Today we are one step closer to providing patients with an immediate and accurate diagnosis, one step closer to providing physicians with the ability to offer better treatment options and one step closer to providing incentive to lower the cost of health care for patients suffering from lupus," Dr. Ahearn said.
"Lupus is the prototypical autoimmune disease and arguably the greatest diagnostic challenge among rheumatologic diseases," he said. "The spectrum of disease among patients with SLE is broad and ranges from subtle or vague symptoms to life-threatening multiorgan failure, and the manifestations of lupus often mimic those of other diseases makes it difficult to diagnose."
It is not unusual for a patient with lupus to seek advice from a variety of specialists and subspecialists over a period of years before b