Lupus nephritis classification system may need improvement
MedWire News: Patients with different lupus nephritis type IV subclasses have similar renal outcomes; therefore, the subclassification of this condition may be unnecessary, study results indicate.
Indeed, the rate of renal death, defined as death occurring in patients in whom doubling of serum creatinine concentration or end-stage renal disease (ESRD) have been observed, did not differ between patients with segmental and diffuse global lupus nephritis type IV, the authors remark.
The classification of lupus nephritis type IV into segmental and global subtypes was suggested by the International Society of Nephrology and the Renal Pathology Society following findings from a study involving 86 patients with type IV lupus nephritis. This study revealed 10-year survival rates of 52% for patients with the segmental subtype and 75% for patients with the global subtype.
To investigate subtype-related differences in renal outcome, Jo Berden (Radboud University, the Netherlands) and colleagues reviewed findings from eight studies that assessed the long-term renal outcomes of type IV lupus nephritis patients. The team found no significant difference in the outcomes of patients with the segmental and global subclasses.
Specifically, the relative risk for renal-related death was a nonsignificant 1.08 for patients with the global compared with the segmental subclass.
Of note, all patients were followed up for a period of time varying from 3 to 13 years.
Regression analysis revealed that patient ethnicity or follow-up duration were unlikely confounding factors.
Writing in the Journal of the American Society of Nephrology, Berden et al say that the current study has several limitations that may affect the overall accuracy of the findings. They cite the small number of studies included in the analysis and the use of group data rather than individual patient data as examples of such limitations.
Berden said that the findings of the current study suggest there is no need for the subclassification of type IV lupus nephritis. She concluded that removing these subtypes may facilitate lupus nephritis categorization by physicians.
By Lauretta Ihonor