A case of rhizomelic chondrodysplasia punctata in newborn

Antenatal ultrasonographic diagnosis of rhizomelic chondrodysplasia punctata

BACKGROUND

Rhizomelic chondrodysplasia punctata (RCDP) is a rare autosomal recessive inherited subtype of a family of congenital anomalies known as chondrodysplasia calcificans punctate (CCP). Given their low rate of occurrence, these cases are highly challenging to diagnose, and because the presence of chondrodysplasia is an indication for legal abortion in Iran, such diagnosis is extremely critical.

CASE PRESENTATION

A 27-year-old white multipara was referred for obstetric ultrasonography at 17 weeks and 6 days of gestation because an ultrasonographic study performed at an outside institution revealed a short femur length. Given the patient's positive family history of chondrodysplasia, she underwent targeted sonography to check the anomaly of the bone and cartilage. The key finding in the sonography was short bones for gestational age.

CONCLUSION

The important clue in this finding was the patient's family history, which made the gynaecologist request an ultrasound to prevent the birth of a child with a congenital disorder. Genetic tests are usually performed on amniocentesis samples. Because the presence of chondrodysplasia is an indication for legal abortion in Iran, finally, the patient underwent legal abortion after amniocentesis and genetic tests.

Neonatal Rhizomelic Chondrodysplasia Punctata Type 1: Weaving Evidence Into Clinical Practice

Rhizomelic chondrodysplasia punctata (RCDP) is a rare genetic peroxisome biogenesis disorder with a reported incidence of 1 in 100 000 live births. The 3 genetic subtypes of RCDP are acquired by an autosomal recessive inheritance pattern. RCDP type 1 accounts for greater than 90% of all aggregate cases. Differentiating between the 3 subtypes of RCDP, as well as disorders characterized by similar punctate cartilaginous changes, is essential to guide an appropriate postnatal plan of care. Management strategies are focused toward associated clinical manifestations and require an interdisciplinary approach including ophthalmology, cardiovascular, endocrine, physical and occupational therapy, and neurology. Purposeful and frequent collaboration among all members of the neonatal/pediatric interdisciplinary team is necessary to optimize outcomes for the neonate and the family unit. The purpose of this article is to anticipate the needs of both patients with known and prenatal diagnosis of RCDP type 1 and patients with suspected clinical diagnosis of RCDP type 1 in the immediate neonatal period and to guide the appropriate plan of care. This article presents a case report of type I RCDP, as well as describes genetic influences, symptoms, diagnosis, management, and prognosis.

Peroxisomes in brain development and function

Peroxisomes contain numerous enzymatic activities that are important for mammalian physiology. Patients lacking either all peroxisomal functions or a single enzyme or transporter function typically develop severe neurological deficits, which originate from aberrant development of the brain, demyelination and loss of axonal integrity, neuroinflammation or other neurodegenerative processes. Whilst correlating peroxisomal properties with a compilation of pathologies observed in human patients and mouse models lacking all or individual peroxisomal functions, we discuss the importance of peroxisomal metabolites and tissue- and cell type-specific contributions to the observed brain pathologies. This enables us to deconstruct the local and systemic contribution of individual metabolic pathways to specific brain functions. We also review the recently discovered variability of pathological symptoms in cases with unexpectedly mild presentation of peroxisome biogenesis disorders. Finally, we explore the emerging evidence linking peroxisomes to more common neurological disorders such as Alzheimer’s disease, autism and amyotrophic lateral sclerosis. This article is part of a Special Issue entitled: Peroxisomes edited by Ralf Erdmann.