Offspring of parents with Balkan Endemic Nephropathy have higher C-reactive protein levels suggestive of inflammatory processes: a longitudinal study

<p>Abstract</p> <p>Background</p> <p>Despite the characteristic extensive tubulointerstitial fibrosis, Balkan Endemic Nephropathy (BEN) is usually considered a non-inflammatory disease.</p> <p>Methods</p> <p>We examined a marker of inflammation, C-reactive protein (CRP), in the offspring of patients with BEN, a population at risk for BEN, prior to development of established disease to determine if an inflammatory process could be identified in the early stages of the disease. In 2003/04, 102 adult offspring whose parents had BEN and a control group of 99 adult offspring of non-BEN patients were enrolled in this prospective study. This cohort was re-examined yearly for four consecutive years. Levels of serum CRP were measured in years 3 and 4 and compared between groups. The data were analyzed with mixed models.</p> <p>Results</p> <p>Compared to controls, offspring of BEN parents had statistically higher CRP levels in two consecutive years, suggestive of early inflammatory reactivity. Whenever the mother was affected by BEN (both parents, or mother only), serum CRP was significantly increased, but not if only the father had BEN. CRP was inversely related to kidney cortex width but not to markers or renal function.</p> <p>Conclusion</p> <p>Early stages of BEN may involve inflammatory processes. The observation of a maternal involvement supports the concept of fetal programming, which has been implicated in the pathogenesis of other chronic kidney diseases.</p

The intellectual influence of economic journals: quality versus quantity

The evaluation of scientific output has a key role in the allocation of research funds and academic positions. Decisions are often based on quality indicators for academic journals, and over the years, a handful of scoring methods have been proposed for this purpose. Discussing the most prominent methods (de facto standards) we show that they do not distinguish quality from quantity at article level. The systematic bias we find is analytically tractable and implies that the methods are manipulable. We introduce modified methods that correct for this bias, and use them to provide rankings of economic journals. Our methodology is transparent; our results are replicable

Metals and kidney markers in adult offspring of endemic nephropathy patients and controls: a two-year follow-up study

Abstract Background The etiology of Balkan Endemic Nephropathy, (BEN), a tubulointerstitial kidney disease, is unknown. Although this disease is endemic in rural areas of Bosnia, Bulgaria, Croatia, Romania, and Serbia, similar manifestations are reported to occur in other regions, for instance Tunisia and Sri Lanka. A number of explanations have been stated including lignites, aristolochic acid, ochratoxin A, metals, and metalloids. Etiologic claims are often based on one or a few studies without sound scientific evidence. In this systematic study, we tested whether exposures to metals (cadmium and lead) and metalloids (arsenic and selenium) are related to Balkan Endemic Nephropathy. Methods In 2003/04 we recruited 102 adults whose parents had BEN and who resided in one of three communities (Vratza, Bistretz, or Beli Izvor, Bulgaria). A control group comprised of 99 adults having non-BEN hospitalized parents was enrolled in the study during the same time. We conducted face-to-face interviews, ultrasound kidney measurements, and determined kidney function in two consecutive investigations (2003/04 and 2004/05). Metals and metalloids were measured in urine and blood samples. To assess the agreement between these consecutive measurements, we calculated intraclass correlation coefficients. Repeated measurement data were analyzed using mixed models. Results We found that cadmium and arsenic were associated with neither kidney size nor function. Lead had a significant but negligible effect on creatinine clearance. Selenium showed a weak but significant negative association with two of the four kidney parameters, namely creatinine clearance and β2-microglobulin. It was positively related to kidney length. These associations were not restricted to the offspring of BEN patients. Adding credence to these findings are reports showing comparable kidney effects in animals exposed to selenium. Conclusion The findings of this 2-year follow-up study indicate that metals and metalloids do not play a role in the etiology of Balkan Endemic Nephropathy. Against the assumption in the literature, selenium was not protective but a risk factor. Since comparable associations were observed in animals, future studies are needed to explore whether selenium may have adverse renal effects in humans.</p