Current diagnostic evaluation of autosomal dominant polycystic kidney disease

Abstract

Despite changing epidemiology of chronic kidney disease, autosomal dominant polycystic kidney disease (ADPKD) is one of the most prevalent causes of end stage renal disease. The first symptoms of the disease occur usually in the 3rd or 4th decade of life, however, it can often be diagnosed much earlier. Advances in the understanding of the disease may lead, in the near future, to slowing the progression of ADPKD in asymptomatic individuals. ADPKD is diagnosed on the basis of family history (autosomal dominant inheritance) and radiological imaging. Ultrasound examination (US) of the kidneys is the most important imaging diagnostic method. US is highly sensitive and specific in patients >30 years of age. In US, Ravine criteria are applied and their modifications with other imaging techniques (computed tomography [CT], magnetic resonance [MR]). In all cases, however, there are multiple cysts in both kidneys and, importantly, concomitant renal enlargement can be observed, which is typical of ADPKD. High expectations for early ADPKD diagnosis are risen by genetics and proteomics. However, these methods are not used routinely. The most sensitive parameter in the evaluation of the disease progression is total renal volume. This parameter is presently used in clinical studies, but its utility in monitoring an individual patient has not been fully proven. Unfortunately, MR and CT are expensive and in case of significantly enlarged kidneys US does not yield accurate assessment of their size and is not sensitive enough for monitoring the disease progression. The rate of glomerular filtration rate (GFR) decline is usually constant. Therefore, it is important to monitor GFR in individuals who have developed renal insufficiency. Other tests, including markers of kidney injury, e.g. albuminuria, or vascular flow parameters, are used mainly in clinical studies. Thus, before more efficient therapeutic approaches have been developed, an early diagnosis and prevention of the disease complications are most essential.