Molecular autopsy for fetal structural anomaly: diagnostic and clinical utility of multidisciplinary team approach

OBJECTIVES

In the West Midlands Regional Genetic Service, cases of perinatal death with a possible genetic diagnosis are evaluated by the Perinatal Pathology Genetic Multidisciplinary Team (MDT). The MDT assessed autopsy findings and considered genomic assessments. The objective of this retrospective service evaluation was to determine the clinical utility of the MDT. This is the first evaluation since the introduction of whole genome and whole exome sequencing in routine clinical care.

METHOD

The outcomes for all the perinatal MDT cases from January 2021 to December 2021 were examined. All cases received a full or partial post-mortem examination (PM) and a chromosomal microarray. Demographics, phenotype, MDT recommendations, genetic testing, diagnoses, outcomes, impact of PM and impact of genetic testing were collected from patient case notes.

RESULTS

One hundred and twenty-three cases were discussed at the MDT meeting in 2021. Genetic evaluation was recommended in 84 cases and accepted in 64 cases. A range of genetic tests were requested according to indication and availability. Thirty diagnoses were identified in 29 cases from 26 unrelated families. The diagnostic yield was 24% (29/123) of all cases or 45% (29/64) of the cases with a suspected genetic diagnosis who underwent genetic testing. PM examination added clinically actionable phenotype data in 79% of cases. A genetic diagnosis enabled accurate counselling of recurrence risk and provision of appropriate follow-up, including prenatal testing and preimplantation diagnosis for patients with inherited conditions.

CONCLUSIONS

Genomic testing was a clinically useful addition to (but not a substitute for) PM examination in perinatal cases associated with structural anomalies. The MDT model helped assess cases and plan appropriate follow-up. Expedited whole genome sequencing or panel-agnostic analysis were most appropriate for heterogeneous presentations. This broad approach can also expand prenatal phenotypes and detect novel disease genes and should be a priority for future research. This article is protected by copyright. All rights reserved.

Facile nanoplastics formation from macro and microplastics in aqueous media

The immense production of plastic polymers combined with their discordancy with nature has led to vast plastic waste contamination across the geosphere, from the oceans to freshwater reservoirs, wetlands, remote snowpacks, sediments, air and multiple other environments. These environmental pollutants include microplastics (MP), typically defined as small and fragmented plastics less than 5 mm in size, and nanoplastics (NP), particles smaller than a micrometer. The formation of micro and nanoplastics in aqueous media to date has been largely attributed to fragmentation of plastics by natural (i.e., abrasion, photolysis, biotic) or industrial processes. We present a novel method to create small microplastics (≲ 5 μm) and nanoplastics in water from a wide variety of plastic materials using a small volume of a solubilizer liquid, such as n-dodecane, in combination with vigorous mixing. When the suspensions or solutions are subjected to ultrasonic mixing, the particle sizes decrease. Small micro- and nanoparticles were made from commercial, real world and waste (aged) polyethylene, polystyrene, polycarbonate and polyethylene terephthalate, in addition to other plastic materials and were analyzed using dark field microscopy, Raman spectroscopy and particle size measurements. The presented method provides a new and simple way to create specific size distributions of micro- and nanoparticles, which will enable expanded research on these plastic particles in water, especially those made from real world and aged plastics. The ease of NP and small MP formation upon initial mixing simulates real world environments, thereby providing further insight into the behavior of plastics in natural settings.

Cardiac function in pregnant women with a Fontan circulation following live birth

Background

Fontan circuits are used to palliate congenital heart disease where patients have a single functioning ventricle. The venous return to the heart is redirected to the pulmonary arteries through the use of a conduit, bypassing the heart. Many females with Fontan circuits are now reaching child-bearing age and some desire pregnancy. However, pregnancy in women with Fontan circuits is associated with high complication rates.

Purpose

We compared postnatal cardiac function in women with a Fontan circulation with pre-pregnancy cardiovascular investigations.

Methods

Data were collected from case notes of all women with a Fontan circulation giving birth after 24 weeks of gestation at Birmingham Women's Hospital between 1997 and 2019.

Results

18 women with a median age of 29±6 years were followed up for 8.0±9 years. There were 21 live births at a median gestation of 32±5 weeks, of which 81% were caesarean sections. Three infants (14%) were born before 30 weeks' gestation and only two (10%) at term. Significant dyspnoea complicated 19% of pregnancies and postpartum haemorrhage occurred in 24%.

Pre-pregnancy cardiac magnetic resonance (CMR) data were available for 11 women and post-pregnancy for 14. Post-pregnancy scans were performed a median of 1.5±4.8 years after birth. Ejection fraction was 63.6±5% at baseline and tended to reduce following pregnancy (median −5.0±8%, n=7). Pre-pregnancy peak oxygen consumption (VO2max) was 73±14% of predicted on cardiopulmonary exercise testing. Median change in VO2max was −8±22% post-pregnancy (n=4). There was no change New York Heart Association (NYHA) class or resting saturations after pregnancy.

Conclusions

Preterm delivery and maternal bleeding were prevalent in this cohort. Exercise capacity was moderately impaired and saturations were typically low. Pregnancy does not seem to have longer term impact on oxygen saturations or NYHA class. Larger series are needed to confirm whether pregnancy is detrimental to postpartum systolic function. CMR can give comprehensive assessment of cardiac function before and after pregnancy and provide data to inform the crucial pre-pregnancy counselling for Fontan patients of child-bearing age.

Funding Acknowledgement

Type of funding source: None

A comparison of teaching strategies for integrating information technology into clinical nursing education

As health care becomes more information-intensive and diverse, there is a need to integrate information technology (IT) into clinical education. Little is known, however, about how to design instructional strategies for integrating information technology into clinical nursing education. This article outlines the instructional strategies used by faculty in five nursing programs who taught students to use a point-of-care information technology system. The article also reports students' computer acceptance and summarizes IT clinical teaching recommendations.

One nurse's experience with technology

This article examines the positive and negative aspects of working with a documentation and information management system from the unique perspective of a practicing home care nurse who was also a student. Aspects of the nightingale tracker technology that are comparable with others used in home care, experiences of field testing, and the nurse's observations can help home care nurses see how this technology can benefit their practice.

Studies of intracellular distribution of acid phosphatase 5 in the spleen cells of leukemic reticuloendotheliosis by isopycnic gradient centrifugation

A fresh spleen sample obtained from a patient with leukemic reticuloendotheliosis was homogenized and subjected to centrifugation on a sucrose density gradient. A major portion of acid phosphatase band 5 was observed in the lysosome, confirming that the elevated phosphatase activity in the neoplastic spleen is a lysosomal enzyme. However, a significant amount of brand 5 was also observed in the microsome. The microsomal and lysosomal enzymes have different affinity to CM-cellulose. The relationship between lysosomal and microsomal enzymes has not been established.