Descriptive and risk factor analysis of nonsyndromic sacral agenesis: National Birth Defects Prevention Study, 1997-2011

Long-term outcomes in sacral agenesis

INTRODUCTION

Sacral agenesis (SA) includes a range of clinical presentations of varying severity, with implications for function and quality of life (QoL). Diagnosis is often made perinatally, and prognostic discussions become an important aspect of parental counselling. This study engaged SA sufferers and their caregivers to obtain objective, long-term patient reported outcome data.

METHOD

Patients with radiologically confirmed SA from a single tertiary spinal unit underwent retrospective medical record review. Patients were then contacted by telephone to complete QoL questionnaires including EQ-ED-5L for adults and EQ-ED-Y for < 16-year-olds. Additional information including Renshaw grade, employment, living situation and bladder function was also collected.

RESULTS

Twenty-six patients with SA were identified. Mean age is 23.35 years (range 0.92-63.53), 13 M:17F. Renshaw grade ranged from 1 to 4. Sixty-eight percent had associated kyphoscoliotic deformities. The majority (70%) had either impaired or absent bladder control, and 80% need walking aids to mobilise. Twenty patients completed the questionnaire (10 adults and 10 < 16-year-olds). Mean EQ-ED-5L index for adults was +0.474 (range -0.1 to +0.089, 1 = best), with a lower mean value of +0.287 (range -0.54 to +1) for the < 16-year cohort. Those undergoing spinal fusion procedures had significantly lower scores (-0.08 v +0.44, p = 0.022).

CONCLUSION

This study provides an objective record of the QoL of individuals with SA, illustrating a wide variety of outcomes, with differences between younger and older individuals which may reflect the results of a long-term adaptive process. The implications for individuals should be carefully tailored to the specific deformity and the likely underlying neurological deficits.

Caudal Regression Syndrome First Diagnosed in Adulthood: A Case Report and a Review of the Literature

Background: Caudal regression syndrome (CRS) is a rare congenital malformation characterized by incomplete development of the lower spine and spinal cord. Its estimated incidence ranges from 1 to 2 per 100,000 live births, leading to a spectrum of clinical presentations. Although most cases are diagnosed during childhood, only a small number of cases have been documented in adults in the medical literature. Case Report: A 27-year-old woman underwent an outpatient magnetic resonance imaging (MRI) of the thoracolumbar spine due to severe lower back pain experienced for the first time. Despite congenital leg abnormalities and multiple childhood surgeries, no further investigations were conducted at that time. MRI revealed congenital anomalies consistent with CRS, including coccygeal agenesis, L5 sacralization, and spinal cord defects. The patient also had a long-standing pilonidal cyst treated conservatively, now requiring operative treatment due to an abscess. Conclusions: This report underscores a rare case of CRS initially misdiagnosed and mistreated over many years. It emphasizes the importance of considering less common diagnoses, especially when initial investigations yield inconclusive results. This clinical case demonstrates a highly valuable and educative radiological finding. In the literature, such cases with radiological findings in adults are still lacking.

Exome sequencing identifies variants in infants with sacral agenesis

BACKGROUND

Sacral agenesis (SA) consists of partial or complete absence of the caudal end of the spine and often presents with additional birth defects. Several studies have examined gene variants for syndromic forms of SA, but only one has examined exomes of children with non-syndromic SA.

METHODS

Using buccal cell specimens from families of children with non-syndromic SA, exomes of 28 child-parent trios (eight with and 20 without a maternal diagnosis of pregestational diabetes) and two child-father duos (neither with diagnosis of maternal pregestational diabetes) were exome sequenced.

RESULTS

Three children had heterozygous missense variants in ID1 (Inhibitor of DNA Binding 1), with CADD scores >20 (top 1% of deleterious variants in the genome); two children inherited the variant from their fathers and one from the child's mother. Rare missense variants were also detected in PDZD2 (PDZ Domain Containing 2; N = 1) and SPTBN5 (Spectrin Beta, Non-erythrocytic 5; N = 2), two genes previously suggested to be associated with SA etiology. Examination of variants with autosomal recessive and X-linked recessive inheritance identified five and two missense variants, respectively. Compound heterozygous variants were identified in several genes. In addition, 12 de novo variants were identified, all in different genes in different children.

CONCLUSIONS

To our knowledge, this is the first study reporting a possible association between ID1 and non-syndromic SA. Although maternal pregestational diabetes has been strongly associated with SA, the missense variants in ID1 identified in two of three children were paternally inherited. These findings add to the knowledge of gene variants associated with non-syndromic SA and provide data for future studies.