A case report of Joubert syndrome with renal involvement and seizures in a neonate

Abstract

Joubert Syndrome is a rare autosomal recessive genetic disorder characterized by a distinctive midbrain-hindbrain malformation that gives the appearance of "the molar tooth sign" on axial magnetic resonance imaging (MRI). Mutations in the implicated genes, affect proteins integral to cellular structures like the primary cilium, basal bodies and centromeres, categorizing Joubert syndrome as a ciliopathy. The most common clinical manifestations include moderate to severe hypotonia in early infancy with ataxia developing later in life, abnormal breathing patterns (tachypnea, apnea), atypical eye movements, development delay and intellectual disabilities. Differential diagnosis between different ciliopathies is challenging due to the overlapping clinical features. French neurologist Marie Joubert was the first to describe the clinical findings in 1969 and later the disorder was named after her. In this report, we present the case of a newborn female patient who was admitted to the neonatal intensive care unit 12 hours after birth, presenting with dyspnea, cyanosis, signs of respiratory distress and seizures. During the course of her hospitalization elevated levels of urea and creatinine were detected and after an abdominal ultrasound and CT evaluation bilateral renal hyperplasia and polycystic kidney disease were discovered. An MRI of the head and neck revealed the presence of inferior vermis agenesis, with a medial crack in cerebellum, a partial dysgenesis of corpus callosum, an underlying and thicker cerebral peduncle, as well as the molar tooth sign suggesting a diagnosis of Joubert syndrome. The diagnosis was ultimately confirmed through molecular genetic testing. Through this case report, we hope to draw attention to this rare and elusive group of disorders and emphasize the value of a prompt diagnosis and a proactive and multidisciplinary approach in the management of these patients.

Keywords: CEP290; Joubert syndrome; MRI; ciliopathy; molar tooth sign.

Fig. 1

FLAIR ax sequence (A and B). There is an elongation of the superior cerebellar peduncles including thickened, elongated, parallel, and horizontally orientated superior cerebellar peduncle(thick white arrows)that gives the shape of the molar tooth (molar tooth sign), the absence of vermis and in B (thin white arrow) the deepening of the interpeduncular fossa.

Fig. 2

Sequence T1 sag (A) a deepened IF (white arrow) and T2 sag. (B) absence/hypoplasia of the vermis is observed(long black arrow), an enlarged fourth ventricle (black asterisk).