Joubert’s syndrome: a case report

Abstract

Joubert syndrome is an autosomal recessive genetic disorder that affects the area of the brain that controls balance and coordination. This syndrome is difficult to diagnose clinically because of its variable phenotype. Signs and symptoms commonly include hypotonia abnormal breathing patterns; abnormal eye movements; ataxia; distinctive facial features; and intellectual disability. Various other abnormalities may also be present. This condition is characterized by a specific finding on an magnetic resonance imaging (MRI) called a "molar tooth sign" in which the cerebellar vermis of the brain is absent or underdeveloped and the brain stem is abnormal. The exact diagnosis is often not made for several years after birth.We present a case of Joubert syndrome in a thirteen year old male with developmental delay, ataxia, mild hypotonia, nystagmus and molar tooth sign on MRI. Awareness of the characteristic clinical and radiological findings in Joubert syndrome will help in early diagnosis, appropriate counselling and proper rehabilitation.

Beyond Childhood: Joubert Syndrome in a 34-Year-Old Female – A Case Report

“…Those who have retinal dystrophy have decreased survival rates and have a higher prevalence of multicystic renal disease. (Bainade et al, 2020) Our patient has no retinal dystrophy thus decreasing the morbidity associated with it.…”

“…A group of disorders known as Joubert syndrome and other related disorders (JSRD) share the MTS and some clinical features of JS but also have other manifestations that may represent a distinct syndrome. (Bainade et al, 2020, Elhassanien et al, 2013 JSRD are categorized according to a newly adopted classification system based on genotype-phenotype correlation: Pure JS, JS with ocular defect, JS with renal defect, JS with oculo-renal defects, JS with hepatic defect, and JS with orofaciodigital defects. (Bainade et al, 2020, Brancati et al, 2010, Akhtar et al, 2019 Another feature of JS is its neuroradiologic characteristics, specifically in magnetic resonance imaging.…”

“…(Bainade et al, 2020, Elhassanien et al, 2013 JSRD are categorized according to a newly adopted classification system based on genotype-phenotype correlation: Pure JS, JS with ocular defect, JS with renal defect, JS with oculo-renal defects, JS with hepatic defect, and JS with orofaciodigital defects. (Bainade et al, 2020, Brancati et al, 2010, Akhtar et al, 2019 Another feature of JS is its neuroradiologic characteristics, specifically in magnetic resonance imaging. MRI studies of patients with JS show a constellation of abnormalities of the central nervous system.…”

“…The primary MR imaging features of JS are thinning of the isthmus with widened interpeduncular fossa, thickened superior cerebellar peduncles, hypoplasia of the cerebellar vermis with fourth ventricular deformity, rostral shift of fastigium, and sagittal vermian cleft due to incomplete fusion of the two halves of vermis. (Bainade et al, 2020, Choh et al, 2009 "Molar tooth sign" encompasses deeper than normal posterior interpeduncular fossa, prominent or thickened superior cerebellar peduncles, and vermian hypoplasia or dysplasia. ( Bainade et al, 2020, Choh et al, 2009, Kendall et al, 1990 The characteristic neurologic finding of JS was shown in our patient's MRI.…”

“…(Al-Smair et al, 2022) It is characterized by hypotonia, ataxia, abnormal breathing patterns, sleep apnea and abnormal eye movements including nystagmus and oculomotor apraxia, developmental retardation with evidence of neuropathologic abnormalities of the cerebellum and brainstem. (Bainade et al, 2020) It is radiographically characterized by hypoplasia of the cerebellar vermis and a molar tooth sign (MTS) that can be seen on magnetic resonance imaging (MRI). ( Al-Smair et al, 2022) More than thirty genes have been identified that cause Joubert syndrome.…”