Unusual Outcome of Primary Hyperoxaluria Type 1 in Adult Patients with 33_34InsC Mutation

Primary hyperoxaluria type 1 is a rare autosomal recessive inborn error based on absence, deficiency or mislocalization of the liver-specific peroxisomal enzyme alanineglyoxylate aminotransferase (AGXT). Some mutations are very rarely described in the adult patients as the 33-34InsC mutation, known as responsible for a terrible severe clinical feature that can lead to early death occurring the childhood period.68 adult patients have been diagnosed for c.33_34InsC, p. G170R, p. I244T, p. F152I, p. G190R, p. W108R and p.976delG mutations in AGXT, as first diagnosed line. We described eight adult patients with a 33-34InsC mutation in homozygote state with a median age of 5012.51 years old. Five of them reached the end stage renal disease (ESRD) at the median age of 55.812.31 years old. The three other patients preserved until now a normal renal function. We observed a mild and unusual clinical course of primary hyperoxaluria toward ESRD with only spontaneous elimination of urolithiasis for the majority of the patients. Primary hyperoxaluria type 1 is a heterogeneous disease and a clinical course of patients with severe PH1 mutations is not dictated primarily by its genotype. The implication of other genetic and/or environmental factors can play a crucial role in determining the ultimate phenotype.