Treatment of primary fetal hydrothorax with OK-432 (Picibanil): Outcome in 14 fetuses and a review of the literature

Background: Primary fetal hydrothorax (PFHT) is an uncommon condition with an estimated prevalence of 1 in 10,000/15,000 pregnancies. Therapeutic interventions include thoracocentesis, thoraco-amniotic shunting (TAS), and pleurodesis using OK-432. Methods: A review of the literature was performed to identify all cases of PFHT treated with TAS and OK-432. All cases of PFHT referred to the Fetal Maternal Unit at Royal Prince Alfred Hospital between 2002 and 2012 were retrospectively reviewed. In the cohort of fetuses treated with OK-432, the main perinatal outcomes evaluated were termination of pregnancy, live birth, neonatal death, and fetal death in utero. Secondary outcomes included gestational age (GA) at diagnosis, GA at treatment, GA at resolution, birth weight, and GA at birth. The development of the children was screened using the Ages and Stages Questionnaires, Version 3 (ASQ-3, 2009). Results: Primary hydrothorax was diagnosed in 31 fetuses, of which 14 had treatment with OK-432. One pregnancy terminated after treatment with OK-432. Survival was 85% (11/13): 100% in fetuses treated with OK-432 without hydrops, and 78% in those treated with hydrops. This compares well to the cases of TAS in the literature with an average survival of 63%: 85% in fetuses without hydrops and 55% with hydrops. The mean GA at birth was 36⁺⁴ weeks and mean birth weight 3,007 g. Eight of the 9 children screened with ASQ-3 scored well within the normal range. Conclusion: OK-432 appears to be a valid treatment option in fetuses with PFHT, particularly in those diagnosed at early GAs.