Long-term follow up of carbonic anhydrase II deficiency syndrome

Area of Science:

• Genetics and rare diseases
• Pediatric endocrinology
• Neurology

Background:

• Carbonic anhydrase II deficiency syndrome is a rare genetic disorder.
• It affects multiple organ systems, including skeletal, neurological, and renal functions.
• Long-term clinical data from affected pediatric populations are limited.

Purpose of the Study:

• To delineate the long-term clinical, biochemical, and radiological spectrum of carbonic anhydrase II deficiency syndrome.
• To describe the natural history and outcomes in a cohort of Saudi Arabian children.
• To identify potential complications and inform management strategies.

Main Methods:

• Retrospective evaluation of medical records of 35 Saudi children diagnosed with carbonic anhydrase II deficiency syndrome.
• Diagnosis confirmed by clinical and radiological findings.
• Carbonic anhydrase II levels measured in a subset of patients.

Main Results:

• Patients exhibited characteristic facial features, growth failure, and psychomotor retardation.
• Distal renal tubular acidosis was a consistent biochemical finding.
• Radiological features included metaphyseal osteopetrosis and progressive intracranial calcification in some cases.
• Complications observed were optic nerve entrapment leading to blindness and bone marrow involvement causing anemia.
• Adult height was significantly reduced in both males and females.

Conclusions:

• Carbonic anhydrase II deficiency syndrome is typically compatible with long-term survival but can lead to severe complications.
• Neurological involvement, particularly cranial nerve compromise, requires vigilant monitoring.
• Regular clinical and neurological assessments are essential for early detection and management of complications.