TY - JOUR
T1 - Serum and urine nitrite and citrulline levels among patients with systemic lupus erythematosus
T2 - A possible addition to activity parameters?
AU - Wanchu, Ajay
AU - Khullar, Madhu
AU - Sud, Kamal
AU - Sakhuja, Vinay
AU - Thennarasu, Kandavel
AU - Sud, Archana
AU - Bambery, Pradeep
PY - 2001
Y1 - 2001
N2 - Nitric oxide (NO) plays a significant role in the inflammatory process and has been implicated in several autoimmune disorders. This study was carried out prospectively to estimate the levels of nitrite and citrulline in the serum and urine, as surrogate markers of NO production, among patients with systemic lupus erythematosus (SLE). Forty-seven patients and 44 age-and sex-matched, healthy volunteers were studied. Nitrite and citrulline were measured in serum and urine by spectrophotometry. Median serum nitrite and citrulline levels and urine citrulline levels were higher among patients as compared with controls (p < 0.05). Patients with skin involvement stood out and had higher median serum and urine citrulline levels (p < 0.05). Disease activity correlated with steroid dosage, serum nitrite levels, and serum and urine citrulline levels (p < 0.05). Steroid dosage correlated with serum citrulline level (p < 0.05). Serum and urine citrulline levels correlated with each other (p < 0.01). In the subset of 13 individuals with renal involvement, serum and urine citrulline levels correlated with each other (p < 0.01) as did urine nitrite and citrulline levels (p < 0.05). NO production is increased among patients with SLE, and this increase correlates with disease activity and dosage of steroids used. The addition of a urine test to measure NO production as a marker of disease activity using simple spectrophotometry can be a valuable adjunct to other tests, can obviate the need for drawing a blood sample for this purpose, and can be repeated as often as necessary.
AB - Nitric oxide (NO) plays a significant role in the inflammatory process and has been implicated in several autoimmune disorders. This study was carried out prospectively to estimate the levels of nitrite and citrulline in the serum and urine, as surrogate markers of NO production, among patients with systemic lupus erythematosus (SLE). Forty-seven patients and 44 age-and sex-matched, healthy volunteers were studied. Nitrite and citrulline were measured in serum and urine by spectrophotometry. Median serum nitrite and citrulline levels and urine citrulline levels were higher among patients as compared with controls (p < 0.05). Patients with skin involvement stood out and had higher median serum and urine citrulline levels (p < 0.05). Disease activity correlated with steroid dosage, serum nitrite levels, and serum and urine citrulline levels (p < 0.05). Steroid dosage correlated with serum citrulline level (p < 0.05). Serum and urine citrulline levels correlated with each other (p < 0.01). In the subset of 13 individuals with renal involvement, serum and urine citrulline levels correlated with each other (p < 0.01) as did urine nitrite and citrulline levels (p < 0.05). NO production is increased among patients with SLE, and this increase correlates with disease activity and dosage of steroids used. The addition of a urine test to measure NO production as a marker of disease activity using simple spectrophotometry can be a valuable adjunct to other tests, can obviate the need for drawing a blood sample for this purpose, and can be repeated as often as necessary.
KW - Citrulline
KW - Nitric oxide
KW - Nitrite
KW - Systemic lupus erythematosus
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U2 - 10.1097/00124743-200102000-00003
DO - 10.1097/00124743-200102000-00003
M3 - Article
C2 - 17039080
AN - SCOPUS:0035111812
SN - 1076-1608
VL - 7
SP - 10
EP - 16
JO - Journal of Clinical Rheumatology
JF - Journal of Clinical Rheumatology
IS - 1
ER -