Fetal Skeletal Dysplasias: Radiologic-Pathologic Classification of 72 Cases
Published in Fetal and Pediatric Pathology, 2022
Sihem Darouich, Aida Masmoudi
Sulfation disorders are associated with DTDST/SLC26A2 deficiency, a transmembrane protein that transports sulfate into chondrocytes to maintain adequate sulfoconjugation of proteoglycans and normal cartilage development. This sulfate transporter is a key limiting factor in the bone growth because of the low capacity of sulfate endogenous synthesis. The lethal form, achondrogenesis type 1B, is associated with lesser capacity of the chondrocyte to incorporate the sulfate, resulting in lack of the ground glass appearance and rarefaction of the cartilage matrix which tends to form dense collagenous rings around chondrocytes, and in severe defects in the intramembranous and endochondral ossifications [24]. These severe histologic alterations are correlated with the significant phenotypic and radiologic anomalies that associate extreme micromelia, short trunk with narrow chest, and diffuse severe ossification defects encompassing lucent skull, thin and short ribs with flared and cupped ends, extremely short long bones with flared, irregular and cupped metaphyses, delayed ossification of the vertebral bodies and sacrum and small square-shaped iliac wings. The cartilage matrix displays in the moderate form, diastrophic dysplasia, variable amount of matrix with pale areas, related to undersulfation of proteoglycans, interspersed with normal areas, along with disruption of the proliferative and hypertrophic zones due to irregular invasion of the metaphyseal capillaries and fibrosis [25]. Consistent with these moderate alterations, micromelia is less severe and the long bones have a normal tubular shape with enlarged metaphyses.
Foetal thoracic hypoplasia: concomitant anomalies and neonatal outcomes
Published in Journal of Obstetrics and Gynaecology, 2022
Munip Akalin, Oya Demirci, Guher Bolat, Ozge Kahramanoglu, Mucize Eric Ozdemir, Ali Karaman
A total of 49 cases diagnosed with thoracic hypoplasia were included in the study. The average maternal age was 28.8 ± 6.1 (17–42) years and the mean body mass index was 28.7 ± 5.5 (18.4–49.8). Nine women (18.4%) had a foetus with a similar anomaly in the previous pregnancy and 13 women (26.5%) had consanguineous marriage. Mean gestational age at diagnosis was 22 weeks (13–37). There were FADS in four cases. All of the cases had skeletal system anomalies which are shown in Table 1. The most common accompanying skeletal system anomaly was micromelia (87.8%). Other system anomalies are shown in Table 2. Head and face anomalies (36.7%) were the second most frequent accompanying foetal anomaly after skeletal system anomalies, and the least common anomaly was genital system anomalies (4.1%). Hydrops fetalis was present in 11 cases (22.4%) at admission and during follow-ups. The average week of diagnosis of hydrops fetalis was 19.8 ± 6.7 (13–36) weeks. When the cases who developed hydrops fetalis were grouped according to whether they had cardiac anomalies, there was no statistically significant difference between the groups (p = .663). A prenatal invasive genetic test was performed in 16 cases and a postnatal genetic test was performed in 7 cases. FGFR-3 gene mutation was investigated in 13 cases. Trisomy 21 in 1 case, trisomy 18 in 1 case and FGFR-3 gene mutation was detected in 1 case. Parents elected the continuation of pregnancy in 23 of the cases (46.9%) and pregnancy was terminated in 26 cases (53.1%). The mean gestational ages of the terminated pregnancies were calculated as 20.3 ± 3.8 (14–29) weeks and all cases were delivered vagin*lly. Among the patients who elected continuation of pregnancy, 34.8% (n = 8) were delivered vagin*lly and 65.2% (n = 15) were delivered by caesarean section. Three of these 23 cases (13%) resulted in foetal demise during follow-ups. The mean gestational ages of foetal death were 31.7 ± 7.0 (25–39) weeks. The mean gestational ages at the birth of 20 cases that resulted in a live birth were 37.0 ± 1.9 (32–41) weeks, the mean birth weight was 2563 ± 775 (1020–3780) g. Apgar scores at 1 and 5 min were 4.05 ± 1.46 and 6.30 ± 1.08, respectively. All newborns were admitted to the NICU. Nineteen out of 20 newborns (95.0%) died in the infantile period. During the follow-ups, 52.6% (n = 10) of the newborns died in the first 24 h of life, 10.5% (n = 2) in the neonatal period and 36.8% (n = 7) in the infantile period. Only 1 (%5) of the 20 cases exceeded the infantile period and reached childhood. Congenital rickets were present in this newborn and thoracic hypoplasia improved after treatment. The mean gestational ages at birth, mean birth weights and Apgar scores at 1 and 5 min of these groups are shown in Table 3. Concomitant heart anomalies, concomitant central nervous system anomalies and the presence of hydrops in newborns who died within the first 24 h were analysed. When grouped as newborns who died within the first 24 h and lived longer, no significant difference was observed between the groups in terms of cardiac anomalies, central nervous system anomalies and hydrops fetalis (p-values are respectively; .596, .701, .156).
