Blog entry by Meguid El Nahas
This meeting organised by Professor Neveen Soliman, Cairo University is proving a great success.The meeting is well attended and intends to introduce young nephrologists and older ones...to the complexity of inherited diseases and challenges of genetics, diagnostics and management in these patients.
A number of excellent talks by Profs Soliman, Sayers and Levtchencko.
Also comprehensive review on hyperoxaluira by Dr Hafez Bazaara followed by discussion of management by Prof Khaled Eweda and Alaa Fayez on the complexities of dual liver and kidney transplantation for patients with type1 hyperoxaluria. Surigcal challenges were highlighted by Dr Fayez who explained difficulties of intraoperative fluid balance between keeping the renal allograft overhydrated and the liver underhydrated...fantastic achievements for Egypt pediatric nephrology and surgery.
I gave a talk on the genetics of kidney disease which highlighted the relevance of genetics of albuminuria, hematuria as well as decreased GFR and its decline in CKD. Key genes appear to be the complex MYH9/APOL1 on chromosome 22 and the increasingly recognised role of the UMOD gene, coding for uromodulin (Tamm-Horsfall protein), in hypertension, hyperuricemia as well as the progression of chronic interstitial disease. Elevated uromodulin urine levels have been associated with increased risk of CKD progression over a 10 year period in a proof of concept study (1).
The latter may explain the uric acid and its "nephrotoxocity" story; those with UMOD mutations may have progressive CKD with elevated uric acid and even gout as main features. Those with raised uric acid in the absence of UMOD mutations may be harmless?
Genotyping of UMOD may highlight those at risk of progression and raise issues related to allopurinol therapy of hyperuricemia to prevent CKD progression. Pilot studies in children with juvenile hyperuricemic nephropathy have proved of limited impact so far (2). Also, of not eallopurinol is capable of reducing BP.
The observations related to UMOD gene mutations illustrate an interesting and emerging concept that common variants in gene regions known to be associated with monogenic diseases may be associated with milder disease-related phenotypes in the general population (3).
1. Kottgen et al.JASN 2010; 21;337-344.
2. Bleyer et al. QJM 2003;96:867-8.
3.O'Seaghadha and Fox. Nephron 2011;118:c55-63
Follow the IKDW meeting on Facebook Global Kidney Community
Lectures will be posted on the new Pediatric Nephrology section of OLA