Citations 114

Acute Interstitial Nephritis: Etiology, Pathogenesis, Diagnosis, Treatment and Prognosis

Nephrology Research & Reviews | November 18, 2013 | Volume: 5 | Issue: 1 | Pages: 13-20

10.4081/nr.2013.e4

Acute interstitial nephritis (AIN) is an important and common cause of acute kidney injury, particularly in hospitalized patients. The classic presentation of AIN includes fever, rash, arthralgias, eosinophilia, and acute kidney injury. While renal biopsy is considered the gold standard for diagnosis, the clinical presentation of fever and rash along with laboratory evidence of peripheral blood eosinophilia, eosinophiluria, and low-grade proteinuria strongly suggest the diagnosis. Histologically, interstitial inflammation with interstitial edema and tubulitis is the hallmark of interstitial nephritis. The most common causative factors are drugs, infections, and certain immune-mediated disorders. Discontinuation of the offending agent is considered the mainstay of therapy while the use of corticosteroids to hasten renal recovery may be beneficial. The role of interstitial nephritis in the pathogenesis of chronic kidney disease and end-stage renal disease is increasingly recognized, further emphasizing the importance of its early diagnosis and timely treatment.
Hypertension in Pregnancy Is a Risk Factor for Microalbuminuria Later in Life

The Journal of Clinical Hypertension | April 29, 2013 | Volume: 15 | Issue: 9 | Pages: 617-623

10.1111/jch.12116 | PMID 24034653

The authors aimed to compare renal function by estimated glomerular filtration rate and albuminuria in 3 groups of women: nulliparous women, women with a history of normotensive pregnancies, and women with a history of at least one hypertensive pregnancy. Women who participated in the second F amily B lood P ressure P rogram S tudy visit (2000–2004) and had serum creatinine and urine albumin measurements (n=3015) were categorized as having had no pregnancy lasting >6 months (n=341), having had only normotensive pregnancies (n=2199), or having had at least 1 pregnancy with hypertension (n=475) based on a standardized questionnaire. Women who reported having had at least one pregnancy with hypertension were significantly more likely to be hypertensive (75.6% vs 59.4%, P <.001), diabetic (34.2% vs 27.3%, P ≤.001), and have higher body mass index (32.8 vs 30.5, P <.001) than those who reported normotensive pregnancies. There was a significantly greater risk of microalbuminuria (urine albumin‐creatinine ratio >25 mg/g) in those who reported at least one pregnancy with hypertension ( odds ratio, 1.37; confidence interval, 1.02–1.85; P =.04) than in those with normotensive pregnancies, after adjusting for risk factors for chronic kidney and cardiovascular disease. Hypertension in pregnancy is associated with an increased risk of future microalbuminuria.
Podocyturia Predates Proteinuria and Clinical Features of Preeclampsia

Hypertension | March 26, 2013 | Volume: 61 | Issue: 6 | Pages: 1289-1296

10.1161/hypertensionaha.113.01115 | PMID 23529165

Podocyturia, the shedding of live podocytes, is present at delivery in women with preeclampsia. The aim of this study was to test whether podocyturia is present earlier in pregnancy and predicts for preeclampsia. We also aimed to compare test characteristics of podocyturia with those of angiogenic factors previously implicated in the pathogenesis of this disorder. We prospectively enrolled 315 women who provided blood and urine samples at the end of the second trimesters of their pregnancies (median, 27 gestational weeks) and within 24 hours of their deliveries (median, 39.5 gestational weeks). Blood samples were analyzed for angiogenic markers, including placental growth factor, the soluble receptor fms-like tyrosine kinase receptor-1 for vascular endothelial growth factor, and endoglin. The urine sediments were analyzed for podocytes, identified by staining for podocin after culturing the urinary sediments for 24 hours. This analysis included all women who developed preeclampsia (n=15), gestational hypertension (n=15), and a subsample of women who remained normotensive throughout pregnancy (n=44), matched for maternal age and number of previous pregnancies to those who developed preeclampsia. At the second trimester collection, all women who developed preeclampsia had podocyturia, compared with none of those who remained normotensive or were diagnosed with gestational hypertension. Podocyturia in the second trimester had a significantly greater sensitivity and specificity for the subsequent diagnosis of preeclampsia than any single angiogenic marker or a combination thereof. Screening for podocyturia at the end of the second trimester may allow for accurate identification of pregnant women at risk for preeclampsia.
Inhibition of p38 MAPK attenuates renal atrophy and fibrosis in a murine renal artery stenosis model

American Journal of Physiology-Renal Physiology | January 31, 2013 | Volume: 304 | Issue: 7 | Pages: F938-F947

10.1152/ajprenal.00706.2012 | PMID 23364805

Renal artery stenosis (RAS) is an important cause of chronic renal dysfunction. Recent studies have underscored a critical role for CCL2 (MCP-1)-mediated inflammation in the progression of chronic renal damage in RAS and other chronic renal diseases. In vitro studies have implicated p38 MAPK as a critical intermediate for the production of CCL2. However, a potential role of p38 signaling in the development and progression of chronic renal disease in RAS has not been previously defined. We sought to test the hypothesis that inhibition of p38 MAPK ameliorates chronic renal injury in mice with RAS. We established a murine RAS model by placing a cuff on the right renal artery and treated mice with the p38 inhibitor SB203580 or vehicle for 2 wk. In mice treated with vehicle, the cuffed kidney developed interstitial fibrosis, tubular atrophy, and interstitial inflammation. In mice treated with SB203580, the RAS-induced renal atrophy was reduced (70% vs. 39%, P < 0.05). SB203580 also reduced interstitial inflammation and extracellular matrix deposition but had no effect on the development of hypertension. SB203580 partially blocked the induction of CCL2, CCL7 (MCP-3), CC chemokine receptor 2 (CCR2), and collagen 4 mRNA expression in the cuffed kidneys. In vitro, blockade of p38 hindered both TNF-α and TGF-β-induced CCL2 upregulation. Based on these observations, we conclude that p38 MAPK plays a critical role in the induction of CCL2/CCL7/CCR2 system and the development of interstitial inflammation in RAS.
Teaching Quality Essentials

American Journal of Medical Quality | October 7, 2012 | Volume: 28 | Issue: 3 | Pages: 214-219

10.1177/1062860612460725 | PMID 23042914

The Role of Angiogenic Factors in the Prediction and Diagnosis of Preeclampsia Superimposed on Chronic Hypertension

Hypertension | February 7, 2012 | Volume: 59 | Issue: 3 | Pages: 555-557

10.1161/hypertensionaha.111.184192 | PMID 22311899

Maternal deaths in women with lupus nephritis: a review of published evidence

Lupus | February 7, 2012 | Volume: 21 | Issue: 5 | Pages: 534-541

10.1177/0961203311434939 | PMID 22311940

Background and objectives: Pregnancies in women with systemic lupus erythematosus (SLE) and lupus nephritis are considered high-risk due to high rates of maternal and fetal complications. However, there has not been a formal analysis addressing the issue of maternal deaths in these women. The aim of this study was to perform a literature review of the maternal deaths in women with SLE and lupus nephritis to: (1) identify the main causes of death and (2) discuss possible reasons for these causes, and strategies that may improve patient care and outcomes. Design, setting, participants, and measurement: We performed an extensive electronic literature search from 1962 to 2009 using online databases (PubMed, Embase, Lilacs, Cochrane Controlled Trials Register, Medline, and Science Citation Index). Studies were included if they reported pregnancies in patients with SLE and lupus nephritis with at least one reported maternal death. Results: We identified 13 studies that reported a total of 17 deaths in the 6 week post-partum period that were attributable to SLE and lupus nephritis. In all cases, death occurred in the setting of active disease, and was attributed either to infection in 41.2% ( n = 7), or disease activity in 29.4% ( n = 5). The remaining deaths were due to pulmonary embolus in 11.8% ( n = 2), pregnancy-associated cardiomyopathy in 5.9% ( n = 1), adrenal failure due to abrupt steroid withdrawal in 5.9% ( n = 1), and undefined in 5.9% ( n = 1). Conclusions: All maternal deaths in patients with SLE and lupus nephritis occurred in those with active disease, with disease activity/complications and infections (mainly opportunistic) being the two major causes. The presented evidence further supports timing of pregnancy relative to SLE activity, and the judicious use of immunosuppressive agents in pregnant patients.
Multiple Causes for Secondary Hypertension in a Young Female

Nephrology Research & Reviews | January 18, 2012 | Volume: 4 | Issue: 1 | Pages: 1-3

10.4081/nr.2012.e1

Secondary causes of hypertension can affect over 10% of those patients diagnosed with hypertension, and the workup can encompass a wide variety of pathologies. Here we present a case of secondary hypertension found in a young physician who, fortunately, had both of these two entities diagnosed via fortuitous imaging performed for non-diagnostic reasons. This case involves a relatively common cause of secondary hypertension (renovascular) and a more obscure cause (paraganglioma). We outline evidencebased surgical and perioperative management of paragangliomas, as well as the medical management of renovascular hypertension. This case is unique in that it involves both elements of secondary hypertension and presents difficult management decisions.
Hypertension during Pregnancy is Associated with Coronary Artery Calcium Independent of Renal Function

Journal of Women's Health | September 28, 2009 | Volume: 18 | Issue: 10 | Pages: 1709-1716

10.1089/jwh.2008.1285 | PMID 19785565

Background: Hypertension during pregnancy (HDP) increases the risk of future coronary heart disease (CHD), but it is unknown whether this association is mediated by renal injury. Reduced renal function is both a complication of HDP and a risk factor for CHD. Methods: Logistic regression models were fit to examine the association between a history of HDP and the presence and extent of coronary artery calcification (CAC), a measure of subclinical coronary artery atherosclerosis, in 498 women from the Epidemiology of Coronary Artery Calcification Study (mean age 63.3 ± 9.3 years). Results: Fifty-two (10.4%) women reported a history of HDP. After adjusting for age at time of study participation, HDP was associated with increased serum creatinine later in life ( p = 0.014). HDP was positively associated with the presence of CAC after adjusting for age at time of study participation (OR = 2.7, 95% CI 1.4-5.4). This association was slightly attenuated with adjustment for body size and blood pressure (OR = 2.4, 95% CI 1.2-4.9) but was not further attenuated with adjustment for serum creatinine and urinary albumin/creatinine ratio (OR = 2.6, 95% CI 1.3-5.3). Results were similar for CAC extent. Conclusions: HDP may increase a woman's risk of future CHD beyond traditional risk factors and renal function. Women with a history of HDP should be monitored for potential increased risk of CHD as they age.
Temporal analysis of signaling pathways activated in a murine model of two-kidney, one-clip hypertension

American Journal of Physiology-Renal Physiology | July 23, 2009 | Volume: 297 | Issue: 4 | Pages: F1055-F1068

10.1152/ajprenal.90439.2008 | PMID 19625373

Unilateral renal artery stenosis (RAS) leads to atrophy of the stenotic kidney and compensatory enlargement of the contralateral kidney. Although the two-kidney, one-clip (2K1C) model has been extensively used to model human RAS, the cellular responses in the stenotic and contralateral kidneys, particularly in the murine model, have received relatively little attention. We studied mice 2, 5, and 11 wk after unilateral RAS. These mice became hypertensive within 1 wk. The contralateral kidney increased in size within 2 wk after surgery. This enlargement was associated with a transient increase in expression of phospho-extracellular signal-regulated kinase (p-ERK), the proliferation markers proliferating cell nuclear antigen and Ki-67, the cell cycle inhibitors p21 and p27, and transforming growth factor-β, with return to baseline levels by 11 wk. The size of the stenotic kidney was unchanged at 2 wk but progressively decreased between 5 and 11 wk. Unlike the contralateral kidney, which showed minimal histopathological alterations, the stenotic kidney developed progressive interstitial fibrosis, tubular atrophy, and interstitial inflammation. Surprisingly, the stenotic kidney showed a proliferative response, which involved largely tubular epithelial cells. The atrophic kidney had little evidence of apoptosis, despite persistent upregulation of p53; expression of cell cycle regulatory proteins in the stenotic kidney was persistently increased through 11 wk. These studies indicate that in the 2K1C model, the stenotic kidney and contralateral, enlarged kidney exhibit a distinct temporal expression of proteins involved in cell growth, cell survival, apoptosis, inflammation, and fibrosis. Notably, an unexpected proliferative response occurs in the stenotic kidney that undergoes atrophy.