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A male neonate weighing 2.9 kg was born at full term by spontaneous vaginal delivery to a 25-year-old gravida 6 mother. There was no history of consanguineous marriage. The mother gave history of having given birth to an earlier 2 female babies with dysmorphic features who had died on day 11 of life. The antenatal period was unremarkable. The neonate did not require resuscitation at birth and developed respiratory distress soon after. Clinical features seen in the patient were as follows:
Yunis-Varon syndrome is an extremely rare inherited multisystem disorder with defects affecting the skeletal, ectodermal tissue and cardio-respiratory systems. Less than sixteen cases have been reported in the world literature. It is characterized by growth retardation prior to and after birth; defective growth of bones of the skull, along with complete or partial absence of the clavicles (cleidocranial dysplasia); characteristic facial features; hypoplasia or absence of thumbs & great toes & distal aphalangea. The first report of this condition appeared in 1980 when Emilio Yunis and Humbuto Varon described 5 children from 3 families with cleidocranial dysplasia associated with certain other dysmorphic features including micrognathia, pelvic dysplasia, bilateral hip dislocation, and retracted and poorly delineated lips.(1) Two of the three sets of parents were consanguineous, suggesting an autosomal recessive disorder. All died before 10 weeks of age. Huges and Partington proposed the designation “the syndrome of Yunis and Varon”.(2) Subsequently, there have been isolated case reports numbering a total of approximately sixteen cases with different additional clinical features (3-10), including two cases reported in India.(9,10) Pfeiffer et al mentioned aplasia of thumbs & great toes as an outstanding feature of the syndrome.(3) Subsequently other features described were severe hearing impairment, pyloric stenosis, atrophy of left lobe of liver and anomalies of hepatic vessels, congenital heart disease (5), severe osteodysplasty, cardiomyopathy (6), spinal defects, hypertension (7), median pseudocleft.(10) CNS defects that have been associated with Yunis Varon syndrome are absence of corpus callosum, arhinencephaly, hamartomatous lesion of lateral ventricles, cerebellar hypoplasia, hydrocephalus, Dandy Walker malformation.(4,7) Aedes et al have described tetralogy of Fallot (5) associated with this syndrome but our patient had a patent ductus arteriosus. Adrenal haemorrhage has been not described any where so far in this syndrome. However, CT brain changes of ischemic changes in temporoparietal region, underdeveloped gyri & bilateral lacunar infarcts in middle cerebral artery territory have been described by Kulkarni et al for the first time.(10) Our patient also had CT brain suggestive of ischemic changes. Walch et al suggested Yunis Varon syndrome as an evidence for a lysosomal storage disorder.(7) Qualitatively abnormal bands for oligosaccharides and neuraminic acid were seen on urine analysis by thin layer chromatography. Autopsy showed prominent intraneuronal inclusions with vacuolar degeneration mainly in thalamic nuclei, dentate nuclei, cerebellar cortex and inferior olivery nuclei. Severe neurological impairment associated with intraneuronal inclusions and vacuolar degeneration has been taken as evidence for a lysosomal storage disorder.(7) Dworzak et al also suggested the possibility of the syndrome resulting from disordered lysosomal storage based on the finding of vacuolar myopathy on muscle biopsy.(8) The prognosis of this
syndrome is poor. Only three of the 13 patients survived the first year
of life (2,5,6), Two of the three survivors developed severe physical
and mental retardation(2,5), and one patient showed growth retardation
with normal intelligence but this child had only a few characteristics
of Yunis Varon syndrome.(6) Huges HE, Partington MW. Brief clinical report: the syndrome of Yunis and Varon - report of a further case. Am J Med Genet 1983;14:539-544 Pfeiffer RA, Diekmann L, Stock HJ. Aplasia of the thumbs and great toes as the outstanding feature of Yunis and Varon syndrome: A new entity, a new observation. Ann Genet 1988;31:241-243. Jones KL. Smith’s Recognizable Patterns of Human Malformation. 5th edition. Philadelphia. WB Saunders Company.1997. pp 410-411. Ades LC, Morris LL, Richardson M, Pearson C, Haan EA. Congenital heart malformation in Yunis-Varon syndrome. J Med Genet 1993;30:788-792. Partington ME. Cardiomyopathy added to the Yunis Varon syndrome. Proc Greenwood Genet 1988;7:224-225 Walch E, Schmidt M, Brenner RE, Emons D, Dame C, Pontz B, et al. Yunis-Varon syndrome: Evidence for a lysosomal storage disease. Am J Med Genet 2000;95:157-160. Dworzak F, Mora M, Borroni C, Cornelio F, Blasevich F, Cappellini A, et al. Generalized lysosomal storage in Yunis-Varon syndrome. Neuromuscul Disord 1995;5:423-428. Bhatia S, Holla RG. Yunis Varon syndrome. Indian Pediatr 2005;42:373-375. Kulkarni ML, Vani HN, Nagendra K et al. Yunis Varon Syndrome. Indian J Pediatr 2006;73(4):353-355. |
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