Ribose 5-phosphate isomerase deficiency

Ribose 5-phosphate isomerase (RPI) deficiency is a very rare enzymopathy of the pentose phosphate pathway with one sole diagnosed case. The patient presented with progressive leukoencephalopathy and peripheral neuropathy. Systematic metabolic profiling identified elevated levels of arabitol and ribitol in affected brain regions and body fluids. RPI gene-sequence analysis revealed a frameshift and a missense mutation.