Establishment of reference intervals for maternal blood and umbilical cord blood procalcitonin in healthy Chinese women in late pregnancy

Procalcitonin levels in pregnancy: A systematic review and meta-analysis of observational studies

BACKGROUND

The utility of procalcitonin to identify obstetric sepsis is unknown.

OBJECTIVE

To calculate the mean (range) procalcitonin in pregnancy among healthy women not in labor (group 1), healthy women in labor (group 2), and women with preterm prelabor rupture of membranes (PPROM) without clinical chorioamnionitis (group 3).

SEARCH STRATEGY

NLM PubMed, Elsevier Embase, and Wiley Cochrane Central Register of Controlled Trials from inception to February 21, 2022.

SELECTION CRITERIA

Ten or more pregnant women with procalcitonin reported at more than 20 weeks of pregnancy, with information on labor, PPROM, and infection. Exclusions were major medical comorbidities.

DATA COLLECTION AND ANALYSIS

Each abstract and full-text review was independently reviewed by the same two authors. Quality was reviewed using the Newcastle-Ottawa Scale. A meta-analysis was performed using a random effects model.

MAIN RESULTS

The systematic review included 25 studies: 10 (40%) of good quality and 15 (60%) of poor quality. The meta-analysis included 21 studies. Mean procalcitonin in group 1 was 0.092 ng/mL (range 0.036-0.049 ng/mL), in group 2 it was 0.130 ng/mL (range 0.049-0.259 ng/mL), and in group 3 it was 0.345 ng/mL (range 0.005-1.292 ng/mL).

CONCLUSIONS

Among healthy pregnant women not in labor, procalcitonin levels are comparable to those in non-pregnant adults and may be useful in identifying infection. Procalcitonin levels in other groups overlap abnormal values of procalcitonin in non-pregnant adults, and may not discriminate infection among women in labor or with obstetric comorbidities.

PROSPERO

CRD42020157376, registered 4/28/2020.

Umbilical Cord Procalcitonin to Detect Early-Onset Sepsis in Newborns: A Promising Biomarker

Background: Up to 7% of neonates born in high-income countries receive antibiotics for suspected early-onset sepsis (EOS). Culture-proven neonatal sepsis has a prevalence of 0.2%, suggesting considerable overtreatment. We studied the diagnostic accuracy of umbilical cord blood and infant blood procalcitonin (PCT) in diagnosing EOS to improve antibiotic stewardship. Methods: Umbilical cord blood PCT was tested in newborns ≥ 32 weeks of gestation. Groups were defined as following: A) culture-proven or probable EOS (n = 25); B) Possible EOS, based on risk factors for which antibiotics were administered for <72 h (n = 49); C) Risk factor(s) for EOS without need for antibiotic treatment (n = 181); D) Healthy controls (n = 74). Additionally, venous or capillary blood PCT and C-reactive protein (CRP) were tested if blood drawing was necessary for standard care. Results: Between June 2019 and March 2021, 329 newborns were included. Umbilical cord blood PCT was significantly higher in group A than in group C and D. No difference between venous or arterial samples was found. Sensitivity and specificity for cord blood procalcitonin were 83 and 62%, respectively (cut-off 0.1 ng/mL). Antepartum maternal antibiotic administration was associated with decreased PCT levels in both cord blood and infant blood directly postpartum in all groups combined. Conclusion: Umbilical cord blood PCT levels are increased in newborns ≥32 weeks with a proven or probable EOS and low in newborns with risk factors for infection, but PCT seems not a reliable marker after maternal antibiotic treatment. PCT could be useful to distinguish infected from healthy newborns with or without EOS risk factors.

Physiological and metabolic adaptations in pregnancy: importance of trimester-specific reference intervals to investigate maternal health and complications

Diagnosis, prognostication, and monitoring of maternal health throughout pregnancy relies on laboratory testing, including but not limited to key markers of thyroid, hepatic, cardiac, hematology, and renal function. Dynamic physiological processes during gestation significantly influence the maternal biochemistry that supports both the mother and fetus. Resultant changes in blood biochemistry alter the expected values of common laboratory tests. However, the importance of pregnancy-specific reference intervals for laboratory test result interpretation and appropriate monitoring of maternal health and complications is underappreciated. Most clinical laboratories continue to use non-pregnant adult reference intervals for laboratory test interpretation in pregnancy. The current review summarizes and critically evaluates the available literature regarding physiological and metabolic adaptations in pregnancy and their influence on common biomarkers of health and disease. The main laboratory parameters discussed include thyroid, hepatic, metabolic, renal, hematology, inflammatory, and cardiac markers. Considering the available data, further studies are urgently needed to establish trimester-specific reference intervals in healthy pregnant women on updated analytical platforms. Without such data, the standard of clinical laboratory service in pregnancy remains compromised and affects the quality of maternal-fetal healthcare.