SLE and Serum Complement: Causative, Concomitant or Coincidental?
Vaneet Sandhu1, Michele Quan2, *
Identifiers and Pagination:Year: 2017
First Page: 113
Last Page: 122
Publisher Id: TORJ-11-113
Article History:Received Date: 09/06/2017
Revision Received Date: 25/07/2017
Acceptance Date: 18/08/2017
Electronic publication date: 30/09/2017
Collection year: 2017
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: (https://creativecommons.org/licenses/by/4.0/legalcode). This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Systemic Lupus Erythematosus (SLE) is an incurable autoimmune disorder with complement activation playing a key role in the pathogenesis of immune-mediated tissue injury. While quantifying complement to monitor SLE disease activity has been the standard of care since the 1950s, decreased complement levels are not consistently associated with flares.
We seek to clarify the SLE phenotype in which complement deficiency is causative, concomitant, or coincidental.
A PUBMED literature review was conducted using key words 'complement,' 'SLE,’ and ‘SLE flares’ in English-only journals from 1972-2017. Relevant clinical studies and review articles were found that examined the measurement of complement levels in SLE, and more specifically, interpretation of low serum complement levels regardless of disease activity.
Complement activation plays a key role in the pathophysiology of SLE and it is recommended to continue monitoring serum levels of C3 and C4 to assess for disease activity. However, it is important to note that decreased serum complement is not consistently associated with disease flares.
It is clinically important to find novel ways to assess disease activity in SLE. Increased serum levels of cell-bound complement activation products may more accurately reflect disease activity than conventional serum C3 and C4 monitoring.