Abstract and Introduction
Joubert Syndrome is a rare, autosomal recessive disorder that affects the cerebellum and brain stem. It presents with a distinct respiratory pattern and profound tachypnea in the newborn period. This article provides an overview of the condition and discusses the embryologic origins of this syndrome. A focused history and systematic physical assessment provide a step-by-step guide to enhance the early recognition of clinical signs and symptoms of this disorder. A series of clinical photographs and a brief case report offer insight into the classic presentation of this uncommon disorder. The diagnosis of Joubert syndrome is confirmed with magnetic resonance imaging, which reveals a classic neuroradiologic finding, characterized as the molar tooth sign. A discussion of the range of developmental outcomes and complex multispecialty care and intensive support that these infants and their families require is also provided.
The Human Genome Project has revolutionized the health care industry. On a daily basis, the genetic origins of many common and not-so-common conditions are uncovered. A myriad of new single-gene defects and syndromes are reported and described. Bedside clinicians are challenged to identify infants with atypical phenotypes and symptom complexes that may lead to the diagnosis of an existing or newly discovered recognizable disorder.
A syndrome is a pattern of multiple malformations, often occurring with specific signs and symptoms, that in combination are thought to be pathogenetically related. Joubert syndrome is a rare autosomal recessive disorder of the cerebellum that occurs in 1 of 100,000 live births.[3,4,5,6,7,8] It was first described in 1969 by Marie Joubert and colleagues, who reported on a 6-month-old infant with an abnormal, rapid breathing pattern and developmental delay. Since then, approximately 200 additional cases have been published in the literature[4–7,10–12]; only 2 of these cases were diagnosed prenatally.[13,14] Males and females are equally affected.
The most common presenting feature in the newborn period is an abnormal breathing pattern, characterized as episodic hyperpnea or panting.[4,7,15] The presence of other features is highly variable, making the syndrome difficult to recognize clinically. Neuroimaging demonstrates an absence or underdevelopment of the cerebellar vermis. The cerebellum is the part of the brain that controls balance and coordination; the cerebellar vermis is involved with posture and rhythmic modulation of stereotypical movements, such as walking.[15–17]
Although the precise etiology of Joubert syndrome is unknown, researchers have identified a group of genes (9q) that may play an important role in development of the cerebellum.[3,18,19] This syndrome likely occurs because of the interruption of a critical step of brain development early in gestation. Understanding the embryologic origins and timing of this disorder is useful in the recognition and treatment of infants with this syndrome.
Adv Neonatal Care. 2003;3(4) © 2003 W.B. Saunders
Cite this: Recognition of the Clinical Signs and Symptoms of Joubert Syndrome - Medscape - Aug 01, 2003.