RESUMO
Introduction: Infantile oxalosis is the most severe form of primary hyperoxaluria type 1 (PH1), with onset of end-stage kidney disease (ESKD) during infancy. We aimed to analyze the outcome of these patients as our current understanding is limited owing to a paucity of reports. Methods: A retrospective registry study was conducted using data from the OxalEurope registry. All PH1 patients with ESKD onset at age <1 year were analyzed. Results: We identified 95 patients born between 1980 and 2018 with infantile oxalosis. Median (interquartile range [IQR]) age at ESKD was 0.4 (0.3-0.5) year. There were 4 patients diagnosed by family screening who developed ESKD despite early diagnosis. There were 11 patients who had biallelic missense mutations associated with vitamin B6 responsiveness. Of 89 patients, 27 (30%) died at a median age of 1.4 (0.6-2.0) years (5-year patient survival of 69%). Systemic oxalosis was described in 54 of 56 screened patients (96%). First transplantation was performed at a median age of 1.7 (1.3-2.9) years. In 42 cases, this procedure was a combined liver-kidney transplantation (LKTx), and in 23 cases, liver transplantations (LTx) was part of a sequential procedure. Survival rates of both strategies were similar. Patient survival was significantly higher in patients born after 2000. Intrafamilial phenotypic variability was present in 14 families of patients with infantile oxalosis. Conclusion: Nearly all screened patients with infantile oxalosis developed systemic disease. Mortality is still high but has significantly improved over time and might further improve under new therapies. The intrafamilial phenotypic variability warrants further investigation.
RESUMO
Several transplant strategies for PH1 have been proposed, and LT is performed to correct the metabolic defects. The patients with PH1 often suffer from ESRD and require simultaneous LKT, which leads to a long wait due to the shortage of suitable organ donors. Five patients with PH1 underwent LDLT at our institute. Three of the five patients were under dialysis before LDLT, while the other two patients were categorized as CKD stage 3. An isolated LDLT was successfully performed in all but our first case, who had complicated postoperative courses and consequently died due to sepsis after retransplantation. The renal function of the patients with CKD stage 3 was preserved after LDLT. On the other hand, our second case with ESRD underwent successful LDKT six months after LDLT, and our infant case is waiting for the subsequent KT without any post-LDLT complications after the early establishment of PD. In conclusion, a two-step transplant strategy may be needed as a life-saving option for patients with PH1 and may be possible even in small infants with systemic oxalosis. While waiting for a subsequent KT, an early resumption of PD should be considered from the perspective of the long-term requirement of RRT.
