Medical Journal of Dr. D.Y. Patil Vidyapeeth

CASE REPORT
Year
: 2016  |  Volume : 9  |  Issue : 1  |  Page : 107--109

Pyle type spondylometaphyseal dysplasia in a neonate: An interesting case


Srinivas Murki1, Sai Kiran Deshbhatla1, Deepak Sharma1, Jaya Nethagani2,  
1 Department of Neonatology, Fernandez Hospital, Hyderabad, Telangana, India
2 Department of Radiology, MJN cancer institute, Hyderabad, Telangana, India

Correspondence Address:
Srinivas Murki
Department of Neonatology, Fernandez Hospital, Hyderabad, Telangana
India

Abstract

Spondylo-metaphyseal dysplasia (SMD) is a bone dysplasia with characteristic vertebral and metaphyseal changes and has different grades of severity depending on the subtype. The exact diagnosis of this infrequently seen skeletal disorder is difficult because of spectrum of severity of bone involvement seen at different ages of life. The most common reported SMD in literature is Kozlowski type (OMIM 184252) and the second most common is SMD corner fracture type (OMIM 184255). We report a case of neonatal SMD on the basis of radiological characteristics.



How to cite this article:
Murki S, Deshbhatla SK, Sharma D, Nethagani J. Pyle type spondylometaphyseal dysplasia in a neonate: An interesting case .Med J DY Patil Univ 2016;9:107-109


How to cite this URL:
Murki S, Deshbhatla SK, Sharma D, Nethagani J. Pyle type spondylometaphyseal dysplasia in a neonate: An interesting case . Med J DY Patil Univ [serial online] 2016 [cited 2019 Dec 15 ];9:107-109
Available from: http://www.mjdrdypu.org/text.asp?2016/9/1/107/167963


Full Text

 Introduction



Spondylometaphyseal dysplasia (SMD) is a bone dysplasia with characteristic vertebral and metaphyseal changes and has different grades of severity depending on the subtype. The exact diagnosis of this infrequently seen skeletal disorder is difficult because of spectrum of severity of bone involvement seen at different ages of life. Symptoms are mild at birth with gradual deterioration in function with age. Prompt and correct diagnosis is very important in order to ensure correct and appropriate treatment and follow-up. [1] We report a case of neonatal SMD on the basis of radiological characteristics.

 Case Report



A male infant presented with apnea and vomiting at 24 h of life. He was term, 2.6 kg male infant, with normal Apgar scores of 8/8/9 at 1, 5, and 10 min. The infant was born to a second degree consanguineous couple with no alive children and previous neonatal death secondary to prematurity. In the present pregnancy, antenatal scans and examination were normal. At the time of presentation, baby had stridor, clinical and neurological examination was unremarkable. Laboratory evaluation sent as part of apnea workup was normal (sugar, serum electrolytes, serum calcium, serum magnesium, head ultrasound). During the course of NICU stay, baby remained asymptomatic and was treated for gastro-esophageal reflux.

On chest X-ray obtained as part of apnea, workup showed metaphyseal widening and dysplasia. Baby was re-evaluated, and there was no obvious dysmorphism. He was 43.5 cm (10 th -25 th centile) in length, head circumference measured 32 cm (10 th -25 th centile), bilateral total arm span was 40 cm, chest circumference was 30 cm, upper segment to lower segment ratio was 1.7:1. There was no family history of any anomalies such as gait disorders, short stature, or kyphoscoliosis.

An infantogram showed involvement of long bones showing predominantly involving long bones, tubular bones of hands, medial ends of clavicles, and sternal ends of ribs. There was also mild to moderate bowing with modeling deformity and widened epiphyseal growth plates with associated shortening of long bones with cupped and widened metaphyses. There was associated splaying of proximal and distal ends of long bones with thinned cortex [Figure 1]. There was also relative constriction of the central portion of the shaft noted and hypoplasia of vertebral bodies with constricted central portion and anterior beaking [Figure 2]. The head ultrasound of the infant was suggestive of normal study. The X-ray findings were suggestive of neonatal SMD. Based on radiological findings, we made a diagnosis of neonatal SMD, Pyle metaphyseal dysplasia.{Figure 1}{Figure 2}

Further investigations done showed normal serum calcium, magnesium, ammonia, phosphate level, alkaline phosphatase, parathormone level, liver and renal function test, TORCH, VDRL, and metabolic screening. Maternal serum calcium, vitamin D, and parathyroid were normal.

 Discussion



The SMDs are a family of a large heterogeneous group of skeletal dysplasias which have characteristic vertebral abnormalities and metaphyseal changes in the long tubular bones. The reported incidence in the literature is around 1 in 100,000 and incidence can be more as many cases are missed because of varied presentation and inability of health personals to identify the disease correctly. Neonatal SMD has characteristic radiological features with minimal phenotypic features. [1]

Classification of SMD is dependent on the associated malformations. Kozlowski made the first classification in 1982 and categorized SMD into seven types, and now there are at least 30 different types of SMD. Our baby was admitted to the nursery for apnea and had incidental detection of metaphyseal dysplasia. SMD usually has associated metaphyseal involvement of the long tubular bones and vertebral bones of the patient. The specific clinical features vary with age of presentation. [1]

Kozlowski type is the most commonly seen SMD and is known to have autosomal dominant inheritance and also rarely X related inheritance. These patients are phenotypically normal at birth, but in infancy they manifest with growth retardation, truncal shortness, and restriction of all joint movement, genu valgum, and scoliosis. Radiographic findings are widening, scalloping, and irregularity of the metaphysis of long tubular bones, shortness of the femoral neck, progressive coxa vara, severe and diffuse platyspondyly of vertebral bodies, delay in ossification of carpal bones, and delay in bone age. [2]

Pyle metaphyseal dysplasia is a rare SMD with autosomal recessive inheritance and is characterized by specific X-ray features and normal phenotypic features. The pathophysiology of Pyle metaphyseal dysplasia is a defect in metaphyseal remodeling which leads to metaphyseal widening of the long tubular bones with associated cortical thinning and osteoporosis. The bones on X-ray produce typical Erlenmeyer-flask deformity. The most common bones involved in decreasing order of frequency are distal end of the humerus; proximal end of tibia; proximal end of humerus and proximal ends of radius and ulna. It has varied vertebral involvement which varies from moderate platyspondyly to biconcave lens appearance of the vertebra. [3]

Spondylo-metaphyseal dysplasia is also known to cause various effects on affected fetus including agenesis of corpus callosum, pachygyria, intrapartum cardiac arrhythmia, and even neonatal death. [4]

The other close differential diagnosis includes are:

Sedaghatian-type SMD: This lethal type of neonatal form of SMD and is characterized by severe metaphyseal chondrodysplasia and associated other anomalies like shortening of limbs, platyspondyly, cardiovascular defects like conduction defects, and central nervous system abnormalities like agenesis of corpus callosum. [5] Goldblatt syndrome or odontochondrodysplasia (ODCD; OMIM#184260). This is very rarely seen condition. This is characterized by short stature, laxity of joints, scoliosis and narrow chest. The radiographic features are characteristic with congenital platyspondyly with coronal clefts, metaphyseal changes involving limbs bone, limb shortening, and coxa valga. [6] Mitochondria-associated granulocyte macrophage colony stimulating factor-signaling gene: This is a novel and severe form of SMD. This is known as PAM16 (presequence translocase-associated motor 16). The clinical features include global developmental delay, facial dysmorphism, narrow chest, prominent abdomen, and short stature due to limbs shorting. The radiograph shows typical bell-shaped thorax, shortened ribs, severe platyspondyly, squared iliac bones, horizontal acetabula or trident acetabula, hypoplastic ischia, short long bones, slight widening of the distal femoral metaphyses, absence of epiphyseal ossification of the knees, wormian bones, decreased interpedicular distance at the lumbar vertebrae. [7]

 Conclusion



Spondylometaphyseal dysplasia is a rarely seen disease in which, radiological evaluation is of extreme importance in diagnosis and classification. Early and correct diagnosis is important, especially in terms of follow-up for skeletal deformity and genetic consultation for the family. Difficulty in typing and defining subgroups underlies the importance for additional studies on SMD.

References

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2Guzman CM, Aaron GR. Spondylometaphyseal dysplasia (Kozlowski type): Case report. Pediatr Dent 1993;15:49-52.
3Turra S, Gigante C, Pavanini G, Bardi C. Spinal involvement in Pyle's disease. Pediatr Radiol 2000;30:25-7.
4Mahendran SM, Wilcox FL, Chirumamila L. Spondylometaphyseal dysplasia-Sedaghatian type associated with intra-partum cardiac arrhythmia and neonatal death. J Obstet Gynaecol 2007;27:851-3.
5English SJ, Gayatri N, Arthur R, Crow YJ. Sedaghatian spondylometaphyseal dysplasia with pachygyria and absence of the corpus callosum. Am J Med Genet A 2006;140A:1854-8.
6Unger S, Antoniazzi F, Brugnara M, Alanay Y, Caglayan A, Lachlan K, et al. Clinical and radiographic delineation of odontochondrodysplasia. Am J Med Genet A 2008;146A:770-8.
7Mehawej C, Delahodde A, Legeai-Mallet L, Delague V, Kaci N, Desvignes JP, et al. The impairment of MAGMAS function in human is responsible for a severe skeletal dysplasia. PLoS Genet 2014;10:e1004311.