Ribose-5-phosphate isomerase deficiency

Ribose-5-phosphate isomerase deficiency
Synonyms	RPI deficiency
Pronounce	N/A
Specialty	N/A
Symptoms	Leukoencephalopathy, developmental delay, seizures, ataxia
Complications	N/A
Onset	Infancy
Duration	Chronic
Types	N/A
Causes	Genetic mutation in the RPIA gene
Risks	Autosomal recessive inheritance
Diagnosis	Genetic testing, MRI, Metabolic screening
Differential diagnosis	Other leukoencephalopathies, Lysosomal storage disorders
Prevention	N/A
Treatment	Supportive care, Symptomatic treatment
Medication	N/A
Prognosis	Variable, often progressive
Frequency	Extremely rare, only a few cases reported
Deaths	N/A

A rare metabolic disorder

Template:Medical condition (new) Ribose-5-phosphate isomerase deficiency is an extremely rare metabolic disorder characterized by a deficiency in the enzyme ribose-5-phosphate isomerase (RPI). This enzyme is crucial in the pentose phosphate pathway, which is important for the production of nucleotides and the management of oxidative stress in cells.

Pathophysiology

Ribose-5-phosphate isomerase is an enzyme that catalyzes the conversion of ribose-5-phosphate to ribulose-5-phosphate. This reaction is part of the non-oxidative phase of the pentose phosphate pathway, which is essential for the synthesis of nucleotides and nucleic acids. A deficiency in this enzyme disrupts the balance of metabolites in the pathway, leading to an accumulation of certain sugars and a deficiency of others, which can affect cellular function and lead to the symptoms observed in this disorder.

Clinical Presentation

The clinical presentation of ribose-5-phosphate isomerase deficiency can vary, but it often includes neurological symptoms such as developmental delay, intellectual disability, and seizures. Some patients may also present with leukoencephalopathy, a condition characterized by the degeneration of white matter in the brain. The severity of symptoms can vary widely among affected individuals.

Diagnosis

Diagnosis of ribose-5-phosphate isomerase deficiency is challenging due to its rarity and the non-specific nature of its symptoms. It often involves a combination of clinical evaluation, magnetic resonance imaging (MRI) of the brain, and specialized metabolic testing. Genetic testing can confirm the diagnosis by identifying mutations in the RPIA gene, which encodes the ribose-5-phosphate isomerase enzyme.

Treatment

Currently, there is no specific treatment for ribose-5-phosphate isomerase deficiency. Management of the condition is primarily supportive and symptomatic. This may include anticonvulsant medications to control seizures, physical therapy, and educational support to address developmental delays. Research into potential therapies is ongoing, but due to the rarity of the condition, progress is slow.

Prognosis

The prognosis for individuals with ribose-5-phosphate isomerase deficiency varies depending on the severity of the symptoms and the effectiveness of supportive care. Some individuals may have a relatively stable course, while others may experience progressive neurological decline.

Epidemiology

Ribose-5-phosphate isomerase deficiency is one of the rarest metabolic disorders, with only a few cases reported in the medical literature. Its exact prevalence is unknown, but it is considered to be extremely rare.

Related pages

• Pentose phosphate pathway
• Metabolic disorder
• Leukoencephalopathy
• Intellectual disability