Outcome of kidney transplantation in type I oral-facial-digital syndrome

OFD1: One gene, several disorders

The OFD1 protein is necessary for the formation of primary cilia and left–right asymmetry establishment but additional functions have also been ascribed to this multitask protein. When mutated, this protein results in a variety of phenotypes ranging from multiorgan involvement, such as OFD type I (OFDI) and Joubert syndromes (JBS10), and Primary ciliary dyskinesia (PCD), to the engagement of single tissues such as in the case of retinitis pigmentosa (RP23). The inheritance pattern of these condition differs from X‐linked dominant male‐lethal (OFDI) to X‐linked recessive (JBS10, PCD, and RP23). Distinctive biological peculiarities of the protein, which can contribute to explain the extreme clinical variability and the genetic mechanisms underlying the different disorders are discussed. The extensive spectrum of clinical manifestations observed in OFD1‐mutated patients represents a paradigmatic example of the complexity of genetic diseases. The elucidation of the mechanisms underlying this complexity will expand our comprehension of inherited disorders and will improve the clinical management of patients.

Renal transplantation in Bardet-Biedl Syndrome

BACKGROUND

Renal anomalies are common in patients with Bardet-Biedl syndrome (BBS), a renal cystic ciliopathy with multi-systemic features. Renal transplantation is indicated in cases of end-stage renal disease (ESRD), but transplant centers may be hesitant to perform the necessary transplant in light of the multitude of metabolic comorbidities these patients often face with the potential to complicate outcomes.

METHODS

Data from the Clinical Registry Investigating BBS (CRIBBS) were used to investigate renal transplant outcomes in the largest BBS cohort described to date.

RESULTS

Of the 206 patients enrolled in the CRIBBS, 21 children (10.2 %; 16 girls, 5 boys; median age 8.4 years) had been diagnosed with ESRD. Renal transplantation was performed in 18 of these individuals between 1982 and 2015, including repeat transplantation in some cases, for a total of 22 kidneys. Overall graft survival was 81.6 % at 1 year post-transplantation, 75.7 % at 5 years, 59 % at 10 years, and 49.2 % at 25 years. Patient survival was 94.4 % at 1 year post-transplantation, 87.2 % at 8 years, and 79.3 % at 25 years.

CONCLUSIONS

At a median follow-up time of 97 months, relatively few complications of renal transplantation were reported in the patients of this study. However, body mass index was significantly elevated in transplanted individuals compared to non-transplanted individuals participating in CRIBBS at the most recent follow-up. Although the frequency of obesity and other manifestations of the metabolic syndrome warrant meticulous management in this high-risk population, favorable long-term outcomes suggest that renal transplantation is a viable option for patients with BBS and ESRD.