IJCM  Vol.4 No.2 , February 2013
Low Levels of Complement Factor C4 Not Always Implicate Disease Activity in Systemic Lupus Erythematosus
ABSTRACT

A lupus patient with a clinically quiescent disease stage will be described who had severely depressed C4 levels while levels of C3 en CH50 were normal. Additional testing revealed a homozygous C4Aisotype deficiency as the cause of the very low C4 levels. It should be emphasized that in SLE, a (very) low C4 level does not always means (subclinical) disease activity.


Cite this paper
E. Borg, H. Velzen-Blad and D. Hamann, "Low Levels of Complement Factor C4 Not Always Implicate Disease Activity in Systemic Lupus Erythematosus," International Journal of Clinical Medicine, Vol. 4 No. 2, 2013, pp. 99-101. doi: 10.4236/ijcm.2013.42019.
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