Urinary C4 excretion in systemic lupus erythematosus

Yoshiteru Ueda, Kohei Nagasawa, Hiroshi Tsukamoto, Takahiko Horiuchi, Seiji Yoshizawa, Tomomi Tsuru, Isao Furugo, Yoshiyuki Niho

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


The fourth component of complement (C4) in urine was measured in 19 patients with systemic lupus erythematosus (SLE). Urinary C4 was detectable in all SLE patients using an enzyme linked immunosorbent assay. In 11 of 13 patients whose urinary C4 was serially measured, a decrease of urinary C4 was found in parallel with a decrease of disease activity of SLE. In the remaining 2 patients, the amount of C4 increased preceding a flare-up of the disease. The measurement of urinary C4 may be useful in evaluating the disease activity of SLE in individual patients and sometimes in predicting the flare-up of the disease. The specific hemolytic activity of excreted C4 and Western blotting analysis showed that urinary C4 consisted mainly of degraded fragments of C4. In two cases, camostat, a serine protease inhibitor, rapidly decreased the urinary C4 excretion, suggesting that the complement activation occurred in the glomerulus in lupus nephritis.

Original languageEnglish
Pages (from-to)11-23
Number of pages13
JournalClinica Chimica Acta
Issue number1
Publication statusPublished - Dec 15 1995

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Clinical Biochemistry
  • Biochemistry, medical


Dive into the research topics of 'Urinary C4 excretion in systemic lupus erythematosus'. Together they form a unique fingerprint.

Cite this