Majewski dwarfism type II: an atypical neuroradiological presentation with a novel variant in the PCNT gene

Abstract

Microcephalic osteodysplastic primordial dwarfism syndrome II (MOPDII) is microcephalic primordial dwarfism and is a very rare form of disproportionate short stature. This disorder shares common features with other forms of microcephalic primordial dwarfism, including severe prenatal and postnatal growth retardation with marked microcephaly. However, it includes characteristic skeletal dysplasia, abnormal dentition and increased risk for cerebrovascular diseases. Recent reports added more features, including café-au-lait lesions, cutis marmorata, astigmatism, Moyamoya disease, insulin resistance, obesity, abnormal skin pigmentation and acanthosis nigricans around the neck. Clearly, the more MOPDII reports that are produced, the more information will be added to the spectrum of MOPDII features that can improve our understanding of this disorder. In this paper, we reported a new case of MOPDII with more severe clinical features, earlier onset of common features, in addition to a homozygous novel variant in the PCNT gene.

Keywords: congenital disorders; developmental paediatrocs; genetics; neonatal health; paediatrics.

Figure 1

Hypoplastic cerebellum/vermis with left orbital hypoplasia and haemorrhage.

Figure 2

An extensive cystic encephalomalacic changes with normal basal ganglia. Remnant brain tissue can be seen mainly in the frontal and temporal regions.

Figure 3

Generalised hypertonia in the flexion position with fixed rotation towards the right side.

Figure 4

Severe microcephaly, fine hair and facial dysmorphic features in forms of beaked nose, retrognathia and low-set ears.

Figure 5

Thoracic scoliosis with spots of skin hypopigmentation and hyperpigmentation.

Figure 6

Inward flexed thumb with single fused interphalangeal crease in the fifth finger.

Figure 7

Microdontia.

Figure 8

Family pedigree and Sanger chromatogram. (A) A pedigree of the family included in this study. (B) Sanger sequencing traces showing the homozygosity of the affected index patient for both variants (in red rectangles) identified in the PCNT and GLRB genes.