Fetal autopsy- An important tool for aetiological diagnosis
Authors: Deepti Chaudhary, Simran Thawani, Nilanjana Mullick, Dr. Prakash Gambhir
Introduction/ Background
Skeletal dysplasia are a heterogeneous group of conditions associated with various
abnormalities of the skeleton. There is a very wide clinicopathological spectrum and
any part of the skeleton can be affected. These are usually diagnosed on antenatal
ultrasound or after birth on the basis of clinical features and radiography.
Chromosomal aneuploidies as well as monogenic disorders, have been implicated as
causes for skeletal dysplasia. Here, we present a case report of one such monogenic
disorder leading to Osteogenesis Imperfecta type VIII.
Clinical history:
A 29 year old primigravida at 21 weeks of gestational age underwent medical termination of
pregnancy in view of congenital anomaly detected by antenatal ultrasound. Antenatal USG
showed tetra micromelia with all long bones, short and curved lower limb bones with normal
calvarium ossification.
Methods/ Procedure
A fetal autopsy and whole exome sequencing (WES) was performed for the product of
conception (POC).
Results
A clinical diagnosis of Osteogenesis Imperfecta type VIII was established based on external
features and radiographic appearance in the context of clinical findings in the fetal autopsy.
WES identified a homozygous mutation in the P3H1 gene, associated with Osteogenesis
imperfecta, type VIII, thus confirming the diagnosis.
Conclusion
Diagnosis of skeletal dysplasia is essential as it enables the identification of the etiology
along with adequate monitoring of the fetal status. Despite recent advances in imaging,
fetal skeletal dysplasias are difficult to diagnose in utero due to a number of factors.
The suspicion of skeletal dysplasia should be followed by a comprehensive work up ranging
from routine fetal USG and doppler to fetal autopsy, fetal x-ray/ infantogram and
placentoscope on the POC/abortus.
A complete genetic evaluation along with routine assessments, including infection, for both
mother and fetus, can facilitate getting the answer along with providing information that will
aid in proper genetic counseling for the family and can help families to interpret, understand
and make informed decisions that can have an impact on future pregnancies.