Wiedemann-Rautenstrauch Syndrome

A number sign (#) is used with this entry because of evidence that Wiedemann-Rautenstrauch syndrome (WDRTS) is caused by compound heterozygous mutation in the POLR3A gene (614258) on chromosome 10q22.

Description

Wiedemann-Rautenstrauch syndrome (WDRTS) is a rare autosomal recessive neonatal progeroid disorder characterized by intrauterine growth retardation, failure to thrive, short stature, a progeroid appearance, hypotonia, and variable mental impairment (summary by Toriello, 1990). Average survival in WDRTS is 7 months, although survival into the third decade of life has been reported (Akawi et al., 2013).

Clinical Features

Based on the observation of 2 sisters reported by Rautenstrauch et al. (1977) and 2 unrelated patients of his own, Wiedemann (1979) suggested the existence of a distinct neonatal progeroid syndrome showing autosomal recessive inheritance. Snigula and Rautenstrauch (1981) gave follow-up information on a patient, then 4 years old, who had been reported by Rautenstrauch et al. (1977).

Devos et al. (1981) described a 4-year-old patient whose parents were double second cousins. The progeroid features were evident at birth, and psychomotor development and physical growth were severely deficient. There was absence of subcutaneous fat with paradoxical accumulation of fat around the buttocks and anogenital area and on the flanks. The hair of the head and the eyebrows and eyelashes were sparse, and ectropion was present. The head could be described as 'pseudohydrocephalic.' Martin et al. (1984) reported the autopsy findings in a 5.5-year-old girl, the patient reported by Devos et al. (1981). The authors concluded that the neuropathologic findings were those of a pure sudanophilic leukodystrophy and provided a useful classification of disorders in this category.

McKusick (1986) noted a case in which macrocephaly was detected antenatally by ultrasound and prompted delivery by cesarean section. The same patient had difficulty swallowing and required tube feeding throughout life, dying at age 13 months. The cranial sutures were wide open, the anterior fontanel had persisted, and there was a prominent venous pattern over the skull. Beaking of the nose may be progressive during infancy, making confusion with the Hallerman-Streiff syndrome (234100) possible.

Ohashi et al. (1987) reported a Japanese infant with the disorder.

Hagadorn et al. (1990) raised the question of heterogeneity; they observed an infant who was typical except for the presence of congenital heart defects and urinary reflux, which had not been reported previously, and the absence of sudanophilic leukodystrophy, cerebral myelination being normal.

Castineyra et al. (1992) described affected sibs, a female and a male, with nonconsanguineous parents. During the first pregnancy, growth retardation, particularly in the biparietal and abdominal dimensions but not in the femoral length, was detected in the female sib through serial ultrasound scans. She was born at 38 weeks' gestation by elective caesarian section and had progeroid features, wide open anterior fontanel, natal teeth, and almost complete absence of subcutaneous fat but with patches of fat in the buttocks. She died at the age of 7 months and received a diagnosis of WDRTS. During the second pregnancy, the same findings were sought by sequential echography and a similar pattern of growth retardation was shown. The pregnancy was terminated, and the male fetus was found to be affected.

Bitoun et al. (1995) described a boy who, in addition to typical features of the syndrome, had congenital hypothyroidism. A follow-up examination showed a partial organification disorder. The parents of the child were consanguineous. The thyroid disorder remained a puzzle until the same type of hypothyroidism was found in his newborn brother without any manifestations of WDRTS.

Hou and Wang (1995) described a Chinese infant girl, born of consanguineous parents, with the phenotypic features of WDRTS without intrauterine growth retardation (IUGR), but with laryngomalacia, camptodactyly, and recurrent skin infection. Hagadorn et al. (1990) had not detected intrauterine growth retardation until 34 weeks of gestation; this, together with the observation of Hou and Wang (1995), suggested that IUGR in neonatal progeroid syndrome occurs late during the third trimester, with variable onset.

Arboleda et al. (1997) reported 3 patients with WDRTS, 2 of whom were male and female sibs. All 3 had short stature, failure to thrive, progeroid appearance, apparent macrocephaly with frontal and parietal bossing, wide fontanels and sutures, prominent scalp veins, sparse scalp hair, eyebrows, and eyelashes, and generalized lipoatrophy. Arboleda et al. (1997) also described radiographic features including craniofacial disproportion, large sutures and fontanels, global hypoplasia of the facial bones, and thin long bones with enlarged metaphyseal endplates, particularly of the femora and tibiae. All 3 patients were karyotypically normal. One child died at 2 weeks of age, one at 6 months of age, and in the third case date of death was not recorded. Arboleda et al. (1997) reported increased levels of prolactin, testosterone, estradiol, and T4, with normal TSH levels and increased serum triglycerides and very low density lipoprotein in one case. Arboleda et al. (1997) proposed that disturbance in the mechanism of bone maturation as well as lipid and hormone metabolism may be etiologically important in WDRTS.

Pivnick et al. (2000) reported 5 patients with neonatal progeroid syndrome and reviewed previously reported cases. Their 5 patients included 2 pairs of sibs, providing further support for autosomal recessive inheritance in this condition. One set of sibs was African American, representing an ethnic occurrence not previously reported. Three patients had abnormalities in endocrine and lipid metabolism. Based on their review of the literature, the authors concluded that significant phenotypic variability occurs in neonatal progeroid syndrome, mild to moderate mental retardation is common, and life expectancy of patients with the condition is about 7 months, although survival past the first decade had been reported.

Arboleda and Arboleda (2005) provided long-term follow-up on a 17-year-old Colombian boy with WDRTS and compared his features to those of 1 of the sisters (patient GM) originally reported by Rautenstrauch et al. (1977), who survived more than 16 years. The Colombian boy had neonatal gynecomastia and galactorrhea, and closure of cranial fontanels and sutures was delayed until 10 years of age. Cultured patient fibroblasts showed limited population doubling, and he had slow visual-evoked potential responses, similar to those in elderly people. At age 17, the boy was short, with a hypotrophic habitus, pseudohydrocephaly, and persistent alopecia of scalp hair, eyebrows, and eyelashes, and he was edentulous. He had a prominent nose, bilateral cryptorchidism, and hypoplasia of the penis, and he had developed scoliosis. He had mild progressive compromise of cognitive function, but unlike patient GM, he did not exhibit ataxia or tremor.

Tunc et al. (2009) reported a Turkish infant, born of nonconsanguineous parents, with intrauterine growth retardation who appeared severely aged at birth. He had pseudohydrocephalus, large fontanels, open cranial sutures, and prominent scalp veins. The face was triangular with micrognathia, small mouth and nose, low-set ears, and neonatal teeth. There was generalized lack of subcutaneous fat, thin wrinkled skin, and hypoplastic nails. He also had hypospadias, which the authors noted had not previously been reported in this disorder.

Arboleda et al. (2011) reported 3 sibs, born of unrelated Colombian parents, with neonatal progeroid syndrome. The parents were flower cultivators with possible exposure to herbicides. At birth, all sibs appeared emaciated with senile facies, wrinkled thin skin, and hypertonia. The frontal and parietal bones were prominent, with scant hair and visible scalp veins. The face was triangular and facial bones were hypoplastic, with pointed chin, prominent supraorbital ridges, and small nose with anteverted nares. Limbs were thin, joints rigid, and hands in a paw-like position. Two patients died within the first week of life, whereas the third survived until day 43.

Kiraz et al. (2012) reported a 2-year-old Turkish girl with Wiedemann-Rautenstrauch syndrome. She had intrauterine growth retardation, abnormal facial appearance with prominent scalp veins, sparse hair, prominent eyes, micrognathia, and loss of teeth. However, she had eyelashes and eyebrows and normal mental development. Motor skills were delayed and movements were slow. Subcutaneous fat was decreased, but she had fat accumulation around the buttocks. Radiographs showed craniofacial disproportion, wide-open sutures and fontanels, osteoporotic changes, and thin ribs. Renal ultrasound showed bilateral pelvicalyceal ectasia, and she had partial syndactyly of the second and third toes. Cardiac evaluation and serum lipids were normal. Kiraz et al. (2012) emphasized the phenotypic variability of this disorder.

Akawi et al. (2013) reported 3 Palestinian sibs, born of first-cousin parents, who had neonatal progeria and long survival. All 3 sibs showed IUGR with an aged appearance at birth, relative macrocephaly, sparse hair and prominent veins on the scalp, and a paucity of subcutaneous fat, without fat accumulation in the buttocks. Dysmorphic features included large eyes, flat malar region, large beaked nose, micrognathia, low-set prominent ears, and large hands and feet, and all showed psychomotor retardation. All 3 had neonatal teeth, and the 2 older patients were edentulous by the second decade of life. At age 27 years, the oldest sib had contractures of the elbow and knee joints and scoliosis. He was on continuous oxygen therapy by mask for chronic lung disease due to repeated chest infections attributed to aspiration, and he had a gastrostomy tube for feeding, due to his inability to swallow. His affected sister and brother were 12 and 7 years old, respectively. The authors noted similarities between the 3 sibs' features and those seen in WDRTS.

Jay et al. (2016) studied a female infant with features of WDRTS, including IUGR, pseudohydrocephalus, alopecia with prominent scalp veins, frontal bossing, triangular face with midface retraction, low-set malformed ears, and natal teeth. She had decreased subcutaneous fat, multiple contractures, long hands, and long rocker-bottom feet. She experienced respiratory distress in the neonatal period due to a narrow trachea and underwent tracheostomy. A gastrostomy tube was placed due to feeding difficulties. She died suddenly at age 7 months due to respiratory complications.

Paolacci et al. (2017) reviewed the phenotypes of patients reported to have WDRTS, and stated that core manifestations included marked prenatal and severe postnatal growth retardation; unusual face, with triangular shape, sparse hair, small mouth, and pointed chin; dental anomalies, including natal teeth and hypodontia; and generalized lipodystrophy with localized fat masses. In addition, progressive ataxia and tremor had been observed in some patients.

Other Features

Using MRI and DEXA scans, O'Neill et al. (2007) examined body fat distribution in 2 unrelated girls, aged 17 years and 10 years, respectively, with neonatal progeroid syndrome. Both had generalized paucity of subcutaneous fat on physical examination, which was most prominent over the extremities. MRI studies showed normal amounts of truncal fat and marked loss of fat from the face and distal extremities. Striking fat loss was also noted in the paravertebral and lateral gluteal regions. Body composition analysis with DEXA scan revealed a marked reduction in both the fat and lean tissue mass. Laboratory studies showed no elevation of fasting glucose, lipids, or insulin. O'Neill et al. (2007) concluded that patients with neonatal progeroid syndrome do not have generalized lipodystrophy, but rather loss of fat confined to the face, distal extremities, and possibly the paravertebral and lateral gluteal regions.

Biochemical Features

Nowak et al. (2006) measured the in vitro proliferative potential of fibroblasts derived from a patient with Wiedemann-Rautenstrauch syndrome (WRS) and found that the life span of the fibroblasts correlated well with their initial telomeric length and was comparable to that seen in normal fibroblasts studied by Cristofalo et al. (1998). Nowak et al. (2006) concluded that the molecular pathogenesis of premature aging symptoms in WRS is not associated with telomere-driven impairment of the replicative senescence program.

Inheritance

Devos et al. (1981) described a 4-year-old patient with the disorder whose parents were double second cousins, consistent with autosomal recessive inheritance.

Pivnick et al. (2000) and Arboleda et al. (2011) favored autosomal recessive inheritance.

Molecular Genetics

In a female infant with Wiedemann-Rautenstrauch syndrome who died at 7 months of age from respiratory complications, Jay et al. (2016) performed exome sequencing and identified compound heterozygosity for a splice site (614258.0002) and a nonsense mutation (R873X; 614258.0008) in the POLR3A gene. Her unaffected parents were each heterozygous for 1 of the mutations, which were not found in healthy controls or in public variant databases.

Paolacci et al. (2018) studied 15 patients from 12 families with WDRTS, including 10 previously reported families (Rautenstrauch et al., 1977; Arboleda et al., 1997; Arboleda and Arboleda, 2005; Morales et al., 2009; Arboleda et al., 2011; Akawi et al., 2013; Paolacci et al., 2017). Compound heterozygous POLR3A variants were identified in affected individuals from 8 families (see, e.g., 614258.0002, 614258.0004, and 614258.0009-614258.0016), and monoallelic variants in the 4 remaining patients; in the latter, lack of genetic material precluded further analyses.

In 7 unrelated patients with WDRTS, including 2 patients previously studied by Garg et al. (2015) (patients 'NLD 1300.4' and 'NLD 2200.4'), Wambach et al. (2018) identified compound heterozygosity for mutations in the POLR3A gene (see, e.g., 614258.0004, 614258.0010, 614258.0014, 614258.0015, 614258.0017, and 614258.0018). All the patients were living, and ranged in age from 2 years to 21 years.

From a cohort of 14 unrelated children with a clinical diagnosis of early-onset segmental progeroid syndrome, who were negative for mutation in the LMNA (150330) and ZMPSTE24 (606480) genes, Lessel et al. (2018) identified 2 patients with compound heterozygous mutations in the POLR3A gene (614258.0018-614258.0020). In a third patient with features that were strikingly similar to those of the 2 children with POLR3A mutations, they identified heterozygosity for the M1? variant (614258.0015), but did not detect a second mutation; the authors suggested that the second mutation might be deeply intronic, a copy-number variant, balanced translocation, or possibly involve a regulatory region of POLR3A.

Exclusion Studies

In 4 Colombian patients with Wiedemann-Rautenstrauch syndrome, including a 22-year-old man originally reported by Arboleda and Arboleda (2005), Morales et al. (2009) analyzed the LMNA gene but did not find any mutations.

In a 2-year-old Turkish girl with Wiedemann-Rautenstrauch syndrome, Kiraz et al. (2012) screened the LMNA gene but found no pathogenic changes.

In 3 Palestinian sibs with neonatal progeria, Akawi et al. (2013) sequenced the LMNA and ZMPSTE24 genes, but identified no mutations. Genomewide linkage analysis mapped the disease to 19p13.3-p13.2, but whole-exome sequencing with prioritization of the mapped region did not reveal any pathogenic mutations.