Interferences in the measurement of circulating phosphate: a literature review.

Background Inorganic phosphate in blood is currently determined by the reaction with molybdate. This report aims at reviewing conditions underlying spuriously altered levels of circulating inorganic phosphate. Content A systematic search of the Excerpta Medica, the National Library Database and the Web of Science database was conducted without language restriction from the earliest publication date available through January 31, 2020. Summary For the analysis, 80 reports published in English (n = 77), French (n = 1), German (n = 1) and Spanish (n = 1) were retained. Well-documented pseudohyperphosphatemia was observed in individuals exposed to liposomal amphotericin, in patients affected by a gammopathy, in patients with hyperlipidemia and in patients with hyperbilirubinemia. An unexplained elevated inorganic phosphate level sometimes provided a clue to the diagnosis of a gammopathy. Well-documented cases of pseudohypophosphatemia were observed in patients on large amounts of intravenous mannitol. Finally, pseudohypophosphatemia was occasionally observed on treatment with liposomal amphotericin and in patients with a gammopathy. Outlook In order to avoid unnecessary testing and treatment, the phenomenon of spuriously altered inorganic phosphate should be recognized. An unexplained hyperphosphatemia may provide a clue to the diagnosis of a gammopathy or a severe hyperlipidemia.

The use of ultrasound-indicated cerclage or cervical pessary in asymptomatic twin pregnancies with a short cervix at midgestation.

INTRODUCTION: Spontaneous preterm birth in women with a twin pregnancy is one of the main causes of perinatal mortality and morbidity. Our aim was to review the perinatal outcome of asymptomatic twin pregnancies with a sonographic short cervical length during the second trimester treated with an ultrasound-indicated cerclage or cervical pessary. MATERIAL AND METHODS: Retrospective study on asymptomatic twin pregnancies with a short cervix (≤ 25 mm) at transvaginal ultrasound examination during the second trimester treated with a cervical cerclage or pessary (2001-2017). The rate of preterm birth < 28, 32 and 34 weeks of gestation, neonatal mortality, neonatal morbidity and composite adverse neonatal outcome were compared in the groups of women treated with cerclage or pessary. RESULTS: Seventy-four twin pregnancies underwent a cerclage while a cervical pessary was inserted in 34 women with twins at our Department: 36 women with an ultrasound-indicated cerclage and 20 with a pessary were included in the analysis. Median gestational age at delivery was higher in women treated with cerclage compared with those with pessary placement (P = .02) and the rate of preterm birth before 34 weeks of gestation was lower in the cerclage group (P = .03). Admissions to the Neonatal Intensive Care Unit were more frequent in pregnancies with pessary (P = .01), the length of admission was longer (P = .005) and composite adverse neonatal outcome occurred more often (P = .03) compared with the cerclage group. CONCLUSIONS: Ultrasound-indicated cerclage appears to reduce the rate of preterm birth before 34 weeks of gestation in asymptomatic twin pregnancies with a short cervix during the second trimester, and also the composite adverse neonatal outcome compared with pessary.