Introduction: According to the European registries, 24% of the pediatric and 38% of the adult patients had an unspecified or unknown primary kidney disease. At least some of these patients suffer from unrecognized rare disease. Knowledge of the primary cause of a disease is essential for adequate classification, prognosis, and most importantly, for the treatment, while it may determine the type of transplantation.
Method: Case-series study that was done at the Clinic for Nephrology, Clinical Center of Montenegro, where we tried to demonstrate correlation between renal transplantation and influence of rare diseases on post-transplantation outcome.
Results: In the period of last ten years 14 patients with rare diseases were successfully tretated with kidney transplantation. Six of these patients had Alport syndrome as primary diseae, 3 DRTA (distal renal tubular acidosis), one Jeune syndrome (ATD – asphyxiating thoracis dystrofy), one C1q nephropathy,one atypical HUS (hemolytic uremic syndrome), one Dent disease and one DiGeorge syndrome and one Caroli's disease.  In the preparation for kidney transplantation we also diagnosed 3 patients with tuberous sclerosis, one with primary hyperoxaluria and one with Mayer Rokitansky Kuster Hauser syndrome, but unfortunately they did not undergo kidney transplantation due to primary disease complcations which made them unsuitable for kidney transplantation. In the follow up period all of these patients still have  functional graft. They had various complications in post transplant period including: urinary tract infections, frequent respiratory tract infections and deterioration of respiratory function (Jeune syndrome), chronic electroyte disbalances, vascular calfications and complications, native kidney and graft stones formations and complications,  epizodes of rejection, skin tumors. All of these patinets needed specific clinical approach and management due to complex nature of prmary disease.
Conclusion: Screening for rare diseases in pre-transplantation period would improve overall outcome of transplantation in these patients. This study emphasizes the importance of early diagnosis and treatment of rare disease and their impact on transplantation outcome.