Rosenthal-Kloepfer syndrome

Rosenthal-Kloepfer Syndrome

Rosenthal-Kloepfer Syndrome, also known as Mucopolysaccharidosis Type IX, is an extremely rare genetic disorder characterized by a deficiency in the enzyme hyaluronidase. This enzyme deficiency leads to the accumulation of hyaluronic acid in the body, causing various clinical symptoms.

History

Rosenthal-Kloepfer Syndrome was first described in the medical literature by Rosenthal and Kloepfer in the late 20th century. Since its initial discovery, only a handful of cases have been documented, making it one of the rarest forms of mucopolysaccharidosis.

Genetics

The syndrome is inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the defective gene, one from each parent, to manifest the disease. The gene responsible for this condition is located on chromosome 3p21.3.

Pathophysiology

The lack of hyaluronidase activity in Rosenthal-Kloepfer Syndrome leads to the accumulation of hyaluronic acid in various tissues. This accumulation can cause joint stiffness, skin abnormalities, and other systemic issues. Unlike other forms of mucopolysaccharidosis, Rosenthal-Kloepfer Syndrome does not typically involve significant intellectual disability or severe organomegaly.

Clinical Features

Patients with Rosenthal-Kloepfer Syndrome may present with:

• Joint stiffness and pain
• Mild facial dysmorphism
• Short stature
• Skin thickening

Diagnosis

Diagnosis is typically made through clinical evaluation, family history, and genetic testing to identify mutations in the gene responsible for hyaluronidase production. Enzyme assays may also be used to measure hyaluronidase activity in leukocytes or fibroblasts.

Treatment

Currently, there is no cure for Rosenthal-Kloepfer Syndrome. Treatment is symptomatic and supportive, focusing on managing joint pain and maintaining mobility. Physical therapy and pain management strategies are often employed.

Prognosis

The prognosis for individuals with Rosenthal-Kloepfer Syndrome varies depending on the severity of symptoms. Most individuals have a normal life expectancy but may experience chronic pain and mobility issues.

Research

Ongoing research is focused on understanding the genetic and biochemical basis of the syndrome, as well as exploring potential enzyme replacement therapies or gene therapies that could address the underlying enzyme deficiency.

See Also

• Mucopolysaccharidosis
• Genetic Disorders
• Enzyme Deficiency Disorders

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NIH genetic and rare disease info

• NIH info on Rosenthal-Kloepfer syndrome

Rosenthal-Kloepfer syndrome is a rare disease.