Patterns of placental pathology in preterm premature rupture of membranes.

Inflammation is associated with preterm premature rupture of membranes (PPROM) and adverse neonatal outcomes. Subchorionic thrombi, with or without inflammation, may also be a significant pathological finding in PPROM. Patterns of inflammation and thrombosis may give insight into mechanisms of adverse neonatal outcomes associated with PPROM. To characterize histologic findings of placentas from pregnancies complicated by PPROM at altitude, 44 placentas were evaluated for gross and histological indicators of inflammation and thrombosis. Student's t-test (or Mann-Whitney U-test), χ 2 analysis (or Fisher's exact test), mean square contingency and logistic regression were used when appropriate. The prevalence of histologic acute chorioamnionitis (HCA) was 59%. Fetal-derived inflammation (funisitis and chorionic plate vasculitis) was seen at lower frequency (30% and 45%, respectively) and not always in association with HCA. There was a trend for Hispanic women to have higher odds of funisitis (OR = 5.9; P = 0.05). Subchorionic thrombi were seen in 34% of all placentas. The odds of subchorionic thrombi without HCA was 6.3 times greater that the odds of subchorionic thrombi with HCA (P = 0.02). There was no difference in gestational age or rupture-to-delivery interval, with the presence or absence of inflammatory or thrombotic lesions. These findings suggest that PPROM is caused by or can result in fetal inflammation, placental malperfusion, or both, independent of gestational age or rupture-to-delivery interval; maternal ethnicity and altitude may contribute to these findings. Future studies focused on this constellation of PPROM placental findings, genetic polymorphisms and neonatal outcomes are needed.

Utilization of TCD screening for primary stroke prevention in children with sickle cell disease.

BACKGROUND: In 1998, the Stroke Prevention Trial in Sickle Cell Anemia showed a >90% reduction in stroke rates after blood transfusion therapy in children with sickle cell disease (SCD) identified as high risk with transcranial Doppler ultrasonography (TCD) screening. METHODS: We studied the utilization of TCD screening in a retrospective cohort of all children with SCD within a large managed care plan from January 1993 to December 2005. Rates of first TCD screening were estimated using life table methods; predictors of TCD were evaluated using Cox proportional hazards regression. Stroke incidence rates were estimated in person-time before (pre-TCD) and after (post-TCD) first TCD. RESULTS: The average annual rate of TCD screening in 157 children with SCD was 1.8 per 100 person-years pre-1998, 5.0 from January 1, 1998, to December 31, 1999, and 11.4 after 1999. The only independent predictor of TCD screening was proximity to the vascular laboratory. The annualized stroke rate pre-TCD was 0.44 per 100 person-years, compared to 0.19 post-TCD. CONCLUSIONS: Since the Stroke Prevention Trial in Sickle Cell Anemia, the rate of transcranial Doppler ultrasonography (TCD) screening in sickle cell disease (SCD) has increased sixfold within a large health care plan. Children living farther from a vascular laboratory are less likely to be screened. Increased availability of TCD screening could improve the utilization of this effective primary stroke prevention strategy.

Neonatal giant pial arteriovenous malformation: genesis or rapid enlargement in the third trimester.

A neonate with congestive heart failure at birth due to a nearly holohemispheric pial arteriovenous malformation is described. This occurred despite a normal second trimester prenatal sonogram. Successful treatment of heart failure was achieved by embolization alone. This case demonstrates that hemodynamically significant lesions may arise later or enlarge more rapidly in utero than previously thought.