The clinical impact of implementing the Roche® bilirubin total Gen.3 method on neonate phototherapy.

OBJECTIVE: To predict the impact of implementing the Roche® Gen.3 bilirubin total method on the number of bilirubin results that would trigger phototherapy using the phototherapy nomogram published in the Canadian Paediatric Society (CPS) Guidelines for Treatment of Hyperbilirubinemia. DESIGN AND METHODS: BILTS method results (N=563) were obtained on the Roche® C501 analyzer and the corresponding Bilirubin Total Gen.3 assay results were derived by linear regression. Total bilirubin results, gestational age and postnatal age were plotted with the CPS phototherapy nomogram to determine if phototherapy was indicated with both the BILTS and Gen.3 methods. Clinical thresholds for phototherapy using the BILTS and new Gen.3 methods were compared by Pearson's chi square test. RESULTS: 284 bilirubin results obtained from infants 35-37 weeks gestation (n=157 neonates) and 279 results from term infants >38 weeks gestation (n=224 neonates) were interpreted with the CPS phototherapy nomogram as either with or without risk factors. Use of the Gen.3 assay reduced the number of bilirubin results that would meet the high-risk threshold line to initiate phototherapy by 7% (p≤0.05) for 35-37 week gestation infants and would reduce phototherapy by 6% (p≤0.05) for >38 week gestation infants with the medium-risk threshold line compared to when the BILTS method was used. CONCLUSIONS: Replacement of the BILTS method by the Gen.3 bilirubin method is anticipated to be associated with a 7% decrease in the number of neonate results that would meet phototherapy thresholds. It cannot be determined if the BILTS assay was associated with a 7% over-treatment or the Gen.3 assay will be associated with 7% under-treatment. While standardization of bilirubin assays remains elusive, nomograms based on bilirubin methods will remain susceptible to method-biases and patient care decisions will remain subject to this uncertainty.

Perinatal and childhood morbidity and mortality in congenital analbuminemia.

Albumin, a serum transport protein, provides 80% of colloid osmotic pressure. Congenital analbuminemia (CAA) is an autosomal recessive disorder characterized by absence of serum albumin. Fifty cases of CAA have been reported throughout the world; however, little is known about its clinical impact. Most reported cases have few clinical signs and symptoms. Twelve local cases from the northwestern central plains region in Saskatchewan were identified and reviewed to ascertain morbidity and mortality related with CAA. All the cases are from two remote First Nations communities. Cases had frequent hospital admissions and recurrent respiratory tract infections. Placental abnormalities included hydropic placentas, placental infarcts and microcalcifications. One-half of the cases were born preterm and one-quarter were small for their gestational age. There were three mortalities in the case series. The present case series suggests increased morbidity and mortality during infancy in patients with CAA. The long-term risks of CAA in this population are unknown and a longitudinal study is recommended.

L'albumine, une protéine du transport sérique, fournit 80 % de la pression colloïdo-osmotique. L'analbuminémie congénitale (AAC) est un trouble autosomique récessif caractérisé par l'absence d'albumine sérique. Cinquante cas d'AAC ont été signalés dans le monde, mais on ne sait pas grand-chose de ses répercussions cliniques. La plupart des cas déclarés s'associaient à peu de signes et symptômes cliniques. Les chercheurs ont dépisté 12 cas locaux, originaires de la région du nord-ouest des plaines centrales, en Saskatchewan, et les ont analysés afin de déterminer la morbidité et la mortalité liées à l'AAC. Tous les cas provenaient de deux communautés éloignées des Premières nations. Ils étaient souvent hospitalisés et avaient des infections respiratoires récurrentes. Les anomalies placentaires incluaient des placentas hydropiques, des infarctus placentaires et des microcalcifications. La moitié des cas étaient prématurés et le quart d'entre eux étaient petits par rapport à leur âge gestationnel. Trois mortalités ont été constatées. Cette série a démontré une augmentation de la morbidité et de la mortalité pendant l'enfance chez les patients ayant une AAC. On ne connaît pas les risques à long terme de l'AAC au sein de cette population. Une étude longitudinale est recommandée.