RAB18 deficiency

RAB18 deficiency is a group of conditions that includes both Warburg Micro Syndrome and Martsolf Syndrome. In Warburg Micro Syndrome, which is the more common form, people may experience severe eye problems, neurological issues, and endocrine abnormalities. Typical eye findings include congenital cataracts in both eyes, smaller than normal eyes (microphthalmia) and corneas (microcornea), and pupils that are less responsive. Even after early cataract surgery, vision may remain poor due to ongoing optic nerve and brain visual processing challenges. Martsolf Syndrome, a milder form of the condition, displays similar types of findings but with less severity. Intellectual disability is common, being severe to profound in Warburg Micro Syndrome and mild to moderate in Martsolf Syndrome. In some cases, people may also experience seizures. Overall, these diseases share many overlapping features, although the severity can vary widely among individuals.

People with RAB18 deficiency often have significant eye issues, including bilateral congenital cataracts, microphthalmia, microcornea, and small, less reactive pupils. Vision problems may persist even after cataract surgery because of progressive damage to the optic pathways. Other common symptoms include intellectual disability, which is severe in Warburg Micro Syndrome and milder in Martsolf Syndrome, muscle stiffness or spasticity that usually starts in the legs and may progress to involve the arms, and, in some cases, epilepsy. There may also be signs of endocrine issues such as underdeveloped genitalia.

RAB18 deficiency is considered a genetic condition. The disorder is defined by an insufficiency of the RAB18 protein, which plays a role in normal body functioning. Most reported cases are classified under Warburg Micro Syndrome, indicating that changes in genes affecting RAB18 may underlie the range of observed symptoms. Detailed genetic information beyond this description is not provided in the current sources.

Information about treatment is currently limited for this condition.

The outlook for people with RAB18 deficiency varies with the severity and type of syndrome. In those with Warburg Micro Syndrome, significant challenges such as marked intellectual disability, ongoing vision problems, and worsening muscle stiffness over time can impact daily functioning and overall quality of life. Individuals with Martsolf Syndrome may experience milder symptoms, although challenges still exist. The progression of symptoms, particularly the gradual increase in muscle stiffness and potential breathing difficulties, underlines the importance of supportive care and monitoring, even though detailed long-term outcome information is limited.

Information about current research on RAB18 deficiency is currently limited for this condition.