David P Bick, MD (@davidpbick) 's Twitter Profile
David P Bick, MD

@davidpbick

Clinical & lab geneticist using genomics to help families find answers. Now @genomicsengland working on screening newborns for treatable genetic disorders.

ID: 1465766218363813891

calendar_today30-11-2021 19:40:13

28 Tweet

82 Followers

6 Following

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

The screening test finds children who will develop disease quickly. They need treatment. But it also finds some children who will not have disease until they are adults. They may not need treatment right away. ncbi.nlm.nih.gov/pmc/articles/P…

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

The purpose of newborn screening is to provide a treatment when it will be most helpful. But some treatments are more risky than others.

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Krabbe disease is a neurodegenerative disease that results from a deficit of the galactosylceramidase enzyme. About 1 in 100K children are born with this.

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Treatment for the infantile onset form of Krabbe disease is hematopoietic stem cell transplantation (bone marrow transplant), a procedure that can be associated with serious complications. …ciencedirect-com.ezproxy3.lhl.uab.edu/science/articl…

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Hematopoietic stem cell transplantation slows but does not stop Krabbe disease progression, even when used in asymptomatic newborns.

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Some of the genetic disorders sought by newborn screening have a very simple treatment. Medium-Chain Acyl-Coenzyme A Dehydrogenase Deficiency or MCADD for short is an example. nhs.uk/conditions/mca…. About 1 in 10K children have this.

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

MCADD is a problem of fat metabolism. Between meals our body uses fat to provide energy but in MCADD the individual can't convert fat to energy fast enough. So, with infections or prolonged fasting these children become ill. Treatment is simple: give extra sugar (glucose).

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

There are a number of genetic disorders that may require urgent treatment in a newborn very soon after birth. Not all are part of a newborn screening at present. One example is pyridoxine-dependent epilepsy due to errors in a gene, ALDH7A1.

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Children with pyridoxine-dependent epilepsy develop seizures that can start very soon after birth. Left untreated this leads to brain damage. Treatment, as early as possible, with pyridoxine (vitamin B6) and diet is essential for the best outcome. pubmed.ncbi.nlm.nih.gov/33200442/

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Different genetic conditions that need urgent treatment soon after birth sometimes use the same treatment. Pyridoxine-dependent epilepsy due the gene ALDH7A1 is treated with pyridoxine (vitamin B6). This is true for pyridoxine-dependent epilepsy due to the gene PLPBP, as well.

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Children with pyridoxine-dependent epilepsy due to errors in the gene PLPBP need to be treated right away because left untreated they will have brain damage. For some, unfortunately, early treatment does not always work. We still have lots to learn. pubmed.ncbi.nlm.nih.gov/33425341/

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Pyridoxine-dependent epilepsy due to errors in the gene PNPO is a genetic condition that needs to be treated immediately, soon after birth. Untreated it leads to brain damage.

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Pyridoxine-dependent epilepsy (PDE) due to errors in the gene PNPO is treated with pyridoxine (vitamin B6) like 2 other genes, PLPBP & ALDH7A1. PDE ranges from 1/20,000 to 1/783,000 live births. orpha.net/consor/cgi-bin…

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Glutamic-oxaloacetic transaminase 2 deficiency due to changes in the gene GOT2 affects brain development, causing severely impaired intellectual development, spasticity and seizures. Specific treatment very early appears to help.

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

GOT2 deficiency is treated with vitamin B6 (pyridoxine) and the amino acid, serine. It was only recently discovered so not a lot is known about long-term outcome. pubmed.ncbi.nlm.nih.gov/33990986/

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Newborn screening finds genetic disorders needing immediate treatment. Families also find it valuable to uncover and treat conditions that appear in the first few years. For example, hyperprolinemia type II due to changes in ALDH4A1 starts months after birth, with seizures.

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Hyperprolinemia type II due to ALDH4A1 is treated with vitamin B6 (pyridoxine). Newborn screening would allow families to prevent the seizures associated with this illness rather than wait for them to occur. pubmed.ncbi.nlm.nih.gov/34037900/

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Which genetic conditions should be screened for in newborns? Hypophosphatasia is a condition resulting in easily broken bones and other problems. A severe, sometimes lethal form occurs at birth. Milder forms occur in children and adults. pubmed.ncbi.nlm.nih.gov/34884378/

David P Bick, MD (@davidpbick) 's Twitter Profile Photo

Will parents want newborn screening for a condition such as hypophosphatasia that may not affect their child before the child is an adult? It is treated with asfotase alfa. Treatment for the condition is expensive. ncbi.nlm.nih.gov/books/NBK47605…