Platelet distribution width (PDW) may be useful as a marker for predicting lupus nephritis (LN), investigators from China reported.
The finding emerged from a study comparing with 212 patients with systemic lupus erythematosus (SLE) and 201 healthy controls. The level of PDW was decreased significantly in the SLE group, and was negatively correlated with SLE disease activity 2000 (SLEDAI-2K) score, Haitao Yu, MD, of The First Hospital of Lanzhou University in China, and colleagues reported in International Immunopharmacology.
The investigators classified patients with SLE into 3 groups based on whether they had a low, normal, or high PDW. They defined low PDW as less than 15%, normal PDW as 15% to 17%, and high PDW as more than 17%. The low-, normal-, and high-PDW groups included 132 (62.3%), 42 (19.8%), and 38 (17.9%) patients, respectively.
Of the 212 patients with SLE, 75 (35.4%) had LN. Compared with the normal- and high-PDW groups, the low-PDW group had significantly more LN cases (55% vs 14% and 6%, respectively; P =.013).
A receiver operating characteristic curve analysis found that the optimal clinical cutoff value for PDW was 12.9, which had 87.4% sensitivity and 74.6% specificity for distinguishing LN from SLE and other types of organ damage, according to Dr Yu’s team.
The study also found that the low-PDW group had significantly higher 24-hour urine protein levels than the normal- and high-PDW groups (0.74 vs 0.40 vs 0.22 g/24 h, respectively; P =.000).
The authors concluded that a low PDW together with high 24-hour urine protein level may provide a strategy to diagnose LN.
Yu H, Jiang L, Liu R, et al. Platelet distribution width as a marker for predicting lupus nephritis. Int Immunopharmacol. 2020;85:106693. doi:10.1016/j.intimp.2020.106693