The association between active proliferative lupus nephritis during pregnancy and small for gestational age newborns.

OBJECTIVES: To analyse maternal variables associated with occurrence of small for gestational age (SGA) newborns in pregnancies of women with systemic lupus erythematosus (SLE), considering clinical and laboratory characteristics prior to conception, during gestation and comorbidities. METHODS: Retrospective cohort study with SLE pregnant patients and singleton deliveries after 22 weeks. SGA newborn was defined as birth weight below 10th percentile and SLE activity at conception and during gestation was measured using the SLE Pregnancy Disease Activity Index (SLEPDAI). Univariate analysis was employed to evaluate individual influence of demographic and clinical variables on the SGA newborn outcome, while variables with p<0.20 were included in multivariate regression. RESULTS: Among 151 pregnancies, 28 (18.5%) had SGA newborns. History of proliferative nephritis (RR=3.84, CI 1.63-9.3) and positivity for anti-RNP and anti-Sm antibodies (RR=2.67, CI 1.11-6.43; 2.78, CI 1.44-5.32) were more frequent in the study group. Active proliferative nephritis at conception (RR=3.29, CI 1.75-6.18) and during gestation (RR=3.63, CI 1.97-6.71), as well as complement C3 consumption (RR=2.70, CI 1.09-6.67) and venous pulse therapy with methylprednisolone (RR=20.3, CI 2.18-190), were also associated with SGA newborns, the latter being independently associated in multivariate regression. Adverse perinatal outcomes, such as stillbirths (4.3 times) and neonatal intensive care unit admissions (3.2 times), were more frequent among SGA infants. CONCLUSIONS: Active proliferative lupus nephritis during pregnancy was associated with SGA newborns, while its treatment with venous pulse therapy with methylprednisolone may play a significant role in this context. Presence of previous proliferative nephritis, SLEPDAI ≥4, C3 consumption and presence of anti-RNP and anti-Sm antibodies were additional variables associated with SGA newborns in this population.

The impact of different classes of lupus nephritis on maternal and fetal outcomes: a cohort study of 147 pregnancies.

OBJECTIVE: To analyze the impact of different classes of lupus nephritis as risk variables for maternal and fetal adverse outcomes in a cohort of pregnant lupus patients. METHODS: This is a cohort study with retrospective and prospective data collection, conducted at the University Hospital of State University of Rio de Janeiro, Brazil, from 2011 to 2016. A total of 147 pregnancies of 137 systemic lupus erythematosus patients of whom 66 had lupus nephritis were included. Demographic and clinical features, as well as maternal and fetal outcomes were observed for each nephritis histological class among systemic lupus erythematosus patients and compared with those without nephritis. Categorical variables were expressed as absolute and relative frequencies and numerical variables as means and standard deviation. The chi-square test with Fisher's correction and Student's t-test were used for statistical analysis. A pvalue < 0.05 was considered statistically significant. RESULTS: Systemic lupus erythematosus patients with proliferative nephritis (classes III/IV, n = 54) presented more frequent disease flares ( p = 0.02), continuous active disease during pregnancy and puerperium ( p = 0.006), hospitalization due to systemic lupus erythematosus ( p < 0.001), hospitalization not directly associated to systemic lupus erythematosus ( p = 0.04), higher frequency of cesarean delivery ( p = 0.03) and preeclampsia ( p = 0.01) than patients without nephritis. Permanent damage measured by Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index was more frequent in classes III/IV than among the other patients. The frequency of adverse fetal outcomes such as prematurity and admission to neonatal intensive care unit were not different among systemic lupus erythematosus patients with or without nephritis. However, perinatal deaths were more frequent in patients with all classes of nephritis ( p = 0.003). CONCLUSION: Systemic lupus erythematosus patients with proliferative nephritis (classes III/IV) have a higher frequency of adverse maternal outcomes. This is probably due to the major impact of proliferative forms of nephritis on women's global heath, which is corroborated by the higher Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index findings, although we cannot exclude the negative influence of disease activity for the maternal adverse events. The findings indicate a need for further lupus nephritis classification beyond the nonspecific term nephritis in the context of lupus pregnancy as the impact on maternal and fetal outcomes varies according to histological class.