Cerebro-costo-mandibular syndrome is a very rare genetic disorder in which mutations in the small nuclear ribonucleoprotein polypeptides B and B1 (SNRPB) genes cause various skeletal anomalies of the thorax and spine. The diagnosis is made based on clinical criteria and the prognosis depends on the severity of defects and associated complications, most important being frequent upper respiratory tract infections.
Presentation
Cerebro-Costo-Mandibular syndrome (CCMS) is presumably inherited through an autosomal dominant mode (although sporadic cases have been identified). This means that symptoms are almost universally seen in the setting of a positive family history. They can commence soon after birth, but the majority of cases are diagnosed during infancy or childhood [1] [2]. The cardinal features of CCMS are:
- Facial changes - Normal development of the palate may be impaired due to insufficient growth of the mandible during fetal life, leading to an abnormally positioned tongue and an underdeveloped mandible (known as micrognathia) that is evident on physical examination [2] [3]. Furthermore, a cleft palate and feeding difficulties are frequently noted [1], and the term "Pierre Robin sequence" is frequently used to describe facial and mandibular features seen in this syndrome [2].
- Defects of the thorax and spine - "rib-gap syndrome" is a synonym for CCMS, the primary reason being the appearance of bilateral multiple posterior rib gaps (most frequently between the 4th and 10th ribs) that are often misidentified as rib fractures [4] [5] [6]. As a result, pulmonary function is significantly reduced. Together with scoliosis and laryngotracheal abnormalities and other prominent findings in CCMS patients, they predispose to profound respiratory obstruction and frequent respiratory tract infections. They are the most important cause of early death. Mortality rates range from 35-50% in the first year of life in the absence of the correct diagnosis and proper management [4] [5]. Blockade of the nasal passage (choanal atresia) may also be encountered, further contributing to the respiratory pathology [5].
- Cranial abnormalities - A very small head circumference with severe microcephaly, as well as mental retardation, is observed in a minority of patients, with the extent of brain damage depending on the time of diagnosis [1] [3] [5].
- Miscellaneous findings - Congenital heart disease (septal defects), a horseshoe kidney, hearing loss, hypoplasia of the elbows and the clavicle and hypospadias are other notable findings in CCMS [1] [2].
Entire Body System
- Poor Feeding
[…] difficulties Feeding problems Poor feeding [ more ] 0011968 Glossoptosis Retraction of the tongue 0000162 Intellectual disability Mental retardation Mental-retardation Mental deficiency Mental retardation, nonspecific [ more ] 0001249 Intrauterine growth [rarediseases.info.nih.gov]
- Accelerated Growth
Figueroa et al. [23] postulated that a certain number of infants with micrognathia show accelerated growth of the mandible during the first year of life, thus resolving airway obstruction. [docplayer.net]
Respiratoric
- Nasal Voice
[…] speech Nasal voice 0001611 Patent ductus arteriosus 0001643 Polyhydramnios High levels of amniotic fluid 0001561 Posteriorly rotated ears Ears rotated toward back of head 0000358 Postnatal growth retardation Growth delay as children 0008897 Renal cyst [rarediseases.info.nih.gov]
Jaw & Teeth
- Abnormal Teeth
[…] of the dentition Abnormal dentition Abnormal teeth Dental abnormalities Dental abnormality [ more ] 0000164 Anomalous rib insertion to vertebrae 0006593 Anomalous tracheal cartilage 0004468 Atrial septal defect An opening in the wall separating the top [rarediseases.info.nih.gov]
Ears
- Hearing Impairment
impairment Conductive deafness Conductive hearing loss [ more ] 0000405 Death in infancy Infantile death Lethal in infancy [ more ] 0001522 Feeding difficulties Feeding problems Poor feeding [ more ] 0011968 Glossoptosis Retraction of the tongue 0000162 [rarediseases.info.nih.gov]
Musculoskeletal
- Short Humerus
humerus Short long bone of upper arm Short upper arms [ more ] 0005792 Thoracic hypoplasia Small chest Small thorax [ more ] 0005257 Showing of 56 | Last updated: 7/1/2019 The majority of cases of cerebro-costo-mandibular syndrome (CCMS) appear to occur [rarediseases.info.nih.gov]
- Flexion Contracture
contracture Contractures of elbows Elbow contracture Elbow contractures [ more ] 0002987 Epicanthus Eye folds Prominent eye folds [ more ] 0000286 Gastroesophageal reflux Acid reflux Acid reflux disease Heartburn [ more ] 0002020 High palate Elevated [rarediseases.info.nih.gov]
- Narrow, Bell-Shaped Thorax
Chest X-ray on the first day of life showed a narrow, bell-shaped thorax with eleven pairs of ribs, with posterior rib-gap defects of the second to ninth rib on both sides (Figure 1a). [docplayer.net]
Neurologic
- Nasal Speech
speech Nasal voice 0001611 Patent ductus arteriosus 0001643 Polyhydramnios High levels of amniotic fluid 0001561 Posteriorly rotated ears Ears rotated toward back of head 0000358 Postnatal growth retardation Growth delay as children 0008897 Renal cyst [rarediseases.info.nih.gov]
Workup
The diagnosis of CCMS may not be easy, as less than 100 cases have been described in the literature [2] [5]. Nevertheless, a detailed patient history regarding the onset of symptoms and a thorough physical examination can provide sufficient data to raise clinical suspicion. The presence of micrognathia and respiratory difficulties necessitate the use of imaging studies, such as plain radiography, computed tomography (CT) or magnetic resonance imaging (MRI). Chest X-rays will reveal a narrow or bell-shaped thorax and bilateral multiple posterior rib gaps, while mandibular hypoplasia can be confirmed using either X-rays or CT [1] [2] [6]. Radiography may be employed if hypoplasia of other skeletal structures (extremities or the clavicles) is suspected as well, whereas cardiac and renal structures should be evaluated by CT or MRI. Additionally, endocranial imaging (preferably MRI) is advocated, particularly if signs of mental retardation exist [2]. Some reports suggest that a prenatal diagnosis of CCMS can be made using fetal ultrasonography and identifying thoracic, facial abnormalities and increased nuchal translucency [6].
Treatment
Treatment - Cerebro-costo-mandibular syndrome Treatment and prognosis depend on the features and severity in each affected person. Resources - Cerebro-costo-mandibular syndrome [checkorphan.org]
A boy, having a mother with Pierre-Robin sequence and a sister with CCMS, was diagnosed prenatally with CCMS and successfully treated with ex utero intrapartum treatment (EXIT) at 36 weeks 6 days of gestation. [ncbi.nlm.nih.gov]
Igor Maric Dusica L Madic Dejan M Petkovic D Velickovic S Gajdobranski Djordje Info HEALTHMED, (2011), vol. 5 br. 6, Suppl. 1, str. 2183-2185 Ispravka ISI/Web of Science Elečas Rang časopisa Citati: Naslov Pediatric femur fractures, epidemiology and treatment [kobson.nb.rs]
Standard Therapies Treatment The treatment of CCMS is based on the symptoms that a person with CCMS has. Treatment may require a group effort from a team of specialists. [rarediseases.org]
Prognosis
CCMS can be classified into three categories--lethal, severe, and mild--according to the severity of the symptoms and prognosis. [ncbi.nlm.nih.gov]
The overall survival rate for patients with this disorder has not been reported, and a classification of the patients on the basis of the prognosis is not yet available. [semanticscholar.org]
Prognosis - Cerebro-costo-mandibular syndrome Not supplied. Treatment - Cerebro-costo-mandibular syndrome Treatment and prognosis depend on the features and severity in each affected person. Resources - Cerebro-costo-mandibular syndrome [checkorphan.org]
Prognosis The analysis using the Kaplan–Meier method revealed that the prognosis was extremely poor ( Fig. 3A ). [onlinelibrary.wiley.com]
Prognosis Prognosis depends upon the severity of anomalies. The most severe forms are often fatal within the first hours after birth and 25% of all reported cases are fatal during the first month of life. [orpha.net]
Etiology
Although several hereditary cases have been reported, the true etiology is unknown. We describe a patient with CCMS in whom palatoplasty was performed at 3 years 8 months. We followed up the patient until 6 years of age. [jstage.jst.go.jp]
Etiology No causative gene has been identified to date. It has been proposed, however, that defects in the sonic hedgehog (SHH) signaling cascade may be responsible for these developmental anomalies. [orpha.net]
Elsevier Health Sciences, ١٨/٠٨/٢٠١٣ - 979 من الصفحات Smith’s Recognizable Patterns of Human Malformation has long been known as the source to consult on multiple malformation syndromes of environmental and genetic etiology as well as recognizable disorders [books.google.com]
“These studies,” says Professor Saint-Jeannet, will identify genes important for neural crest and craniofacial development, and will provide novel insights into the etiology and pathogenesis of Nager syndrome. [nyu.edu]
Elsevier Health Sciences, 18 ago 2013 - 979 pagine Smith’s Recognizable Patterns of Human Malformation has long been known as the source to consult on multiple malformation syndromes of environmental and genetic etiology as well as recognizable disorders [books.google.it]
Epidemiology
Maric Dusan M Djan Igor Maric Dusica L Madic Dejan M Petkovic D Velickovic S Gajdobranski Djordje Info HEALTHMED, (2011), vol. 5 br. 6, Suppl. 1, str. 2183-2185 Ispravka ISI/Web of Science Elečas Rang časopisa Citati: Naslov Pediatric femur fractures, epidemiology [kobson.nb.rs]
Summary Epidemiology More than 80 cases have been reported to date; both males and females are equally affected. Clinical description CCMS is characterized by orofacial and costovertebral developmental anomalies. Severity is highly variable. [orpha.net]
Eur J Pediatr (1989) 1.00 Limb defects associated with major congenital anomalies: clinical and epidemiological study from the International Clearinghouse for Birth Defects Monitoring Systems. [pubrank.carbocation.com]
Prevention
EXIT would be an effective option for rescuing patients with prenatally diagnosed CCMS and preventing neonatal hypoxia. [ncbi.nlm.nih.gov]
Symptoms - Cerebro-costo-mandibular syndrome Causes - Cerebro-costo-mandibular syndrome Prevention - Cerebro-costo-mandibular syndrome Not supplied. Diagnosis - Cerebro-costo-mandibular syndrome Not supplied. [checkorphan.org]
Management: Includes intensive care for improving neonatal respiratory function Prevention of feeding difficulties. Operative interventions - musculoskeletal, palatal or hearing problems. [medicalchemy-syndromes.blogspot.com]
TIS is a disorder where severe problems in how the chest, spine, and ribs are formed prevent normal breathing and lung development. [rarediseases.org]
References
- Tooley M, Lynch D, Bernier F, Parboosingh J, Bhoj E, Zackai E, et al. Cerebro-costo-mandibular syndrome: Clinical, radiological, and genetic findings. Am J Med Genet A. 2016;170A(5):1115-1126.
- Abdalla W, Panigrahy A, Bartoletti SC. Cerebro-costo-mandibular syndrome: Report of two cases. Radiol Case Rep. 2011;6(3):495.
- Watson TA, Arthurs OJ, Muthialu N, Calder AD. Multi-detector thoracic CT findings in cerebro-costo-mandibular syndrome: rib gaps and failure of costo-vertebral separation. Skeletal Radiol. 2014;43(2):263-266.
- Nagasawa H, Yamamoto Y, Kohno Y. Cerebro-costo-mandibular syndrome: prognosis and proposal for classification. Congenit Anom (Kyoto). 2010;50(3):171-174.
- Ramaswamy P, Negus S, Homfray T, De Rooy L. Severe micrognathia with rib dysplasia: cerebro-costo-mandibular syndrome. Arch Dis Child Fetal Neonatal Ed. 2016;101(1):F85.
- Hosalkar HS, Shaw BA, Ceppi CL, Ng BC. The cerebro-costo-mandibular syndrome: 9-year follow-up of a case. J Postgrad Med. 2000;46:268.