Pre-existing Renal Insufficiency Research Articles

Renal tubular acidosis type IV in hyperkalaemic patients - a fairy tale or reality?

Hyperkalaemia is a common feature in hospitalized patients and often attributed to drugs antagonizing the renin-angiotensin-aldosterone system (RAAS) and/or acute kidney injury (AKI), despite significantly preserved glomerular filtration rate (GFR). The objective of this study was to determine the prevalence and role of renal tubular acidosis type IV (RTA IV) in the development of significant hyperkalaemia. A single-centre retrospective study. Patients admitted to a University Hospital over 12months. Patients with a potassium value >6·0mm were identified. Clinical and laboratory data were revisited, and patients with a normal anion gap metabolic acidosis were evaluated for the existence of RTA IV. A total of 57 patients having significant hyperkalaemia (>6·0mm) were identified. Twelve patients had end-stage renal disease, while 21 patients had solely AKI or progressive chronic renal failure. RTA IV was present in 24 patients (42%), of whom 71% had pre-existing renal insufficiency because of diabetic nephropathy or tubulointerstitial nephritis. All hyperkalaemic patients with urinary/serum electrolytes suggestive of RTA IV had evidence of AKI, but creatinine levels were significantly lower (P<0·05), while the number of drugs antagonizing the RAAS was comparable. We demonstrated that RTA IV (i) is very common in patients with hyperkalaemia; (ii) should always be suspected in hyperkalaemic patients with only moderately impaired GFR; and (iii) may result in significant hyperkalaemia in the presence of both AKI and drugs antagonizing the RAAS.

Trends in the surgical management of localized renal masses: thermal ablation, partial and radical nephrectomy in the USA, 1998–2008

To evaluate the diffusion of nephron-sparing modalities (NSM) for the treatment of renal neoplasms in the USA over the last decade and to identify the factors associated with renal procedure selection. The Nationwide Inpatient Sample was utlized to identify patients undergoing cryo/radiofrequency ablation (C/RFA), radical nephrectomy (RN) and partial nephrectomy (PN) from 1998 to 2008. Annual trends in procedure prevalence were determined. Multivariate analyses were performed to query the influence of age, race, sex and comorbid disease on surgery selection. We identified 443,853 procedures performed during the study period: 25,599 C/RFA, 79,568 PN and 338,687 RN. The prevalence per 100,000 hospital admissions in 1998 was 3.7 for C/RFA, nine for PN and 87.1 for RN. All procedures increased over the study period, by 1.05, 3.1 and 2.2/100,000 admissions per year, respectively (all P < 0.001). Diabetes, urban, teaching and large capacity hospitals were associated with NSM (either C/RFA or PN) compared to RN (all P ≤ 0.011). Age ≥70 years, female, hypertension, diabetes, chronic kidney disease (CKD) and region outside the Northeast favoured C/RFA over PN (all P ≤ 0.026). Compared to those without CKD, patients with CKD had an almost twofold higher probability of undergoing RN than NSM (odds ratio, 1.88; 95% confidence interval, 1.7-2.1). Despite increasing NSM utilization over the study period, most patients with CKD still received RN. Although the prevalence of NSM is increasing, RN is more common. The low utilization of NSM in patients with pre-existing CKD warrants further investigation.

Temporary Balloon Occlusion of the Common Hepatic Artery for Yttrium-90 Glass Microspheres Administration in a Patient with Hepatocellular Cancer and Renal Insufficiency

The most severe complication of yttrium-90 therapy is gastrointestinal ulceration caused by extrahepatic dispersion of microspheres. Standard pretreatment planning requires extensive angiographic evaluation of the hepatic circulation and embolization of hepatoenteric collaterals; however, in patients with severe renal insufficiency, this evaluation may lead to acute renal failure. In order to minimize iodinated contrast utilization in a patient with preexisting severe renal insufficiency, the authors describe the use of a balloon catheter for temporary occlusion of the common hepatic artery to induce transient redirection of flow of the hepatoenteric arteries towards the liver, in lieu of conventional coil embolization.

Pathophysiology of the contrast media-induced nephropathy (CIN) in patients undergoing coronary interventions

Contrast media-induced nephropathy (CIN) is a known complication of intra-arterial application of radiographic contrast media (RCM) and is associated with both short- and long-term outcomes. The development of CIN is not easy to diagnose due to a lack of a uniform definition of CIN. CIN was reported in 4 to 20% of patients after intra-arterial RCM administration during coronary angiography. An all-cause mortality rate of CIN patients amounted to 9% compared with 2% among patients not developing CIN. Pre-existing chronic renal insufficiency, especially, was described as important factor predisposing for CIN, but there was recent clinical evidence that CIN may occur also in low risk ambulatory patients, probably depending on the type of RCM used. Strongly depending on the type of RCM administered there were marked differences in the morphological changes of erythrocytes as well as endothelial cells coinciding in some cases with microcirculatory disorders in patients as well as in animal models. Iodixanol brought about the least cellular and microcirculatory effects while Iopromide induced the strongest disturbances in capillary perfusion and myocardial oxygen tension. It is unclear, however, whether this favours the development of CIN.

Impact of anemia on contrast-induced nephropathy (CIN) in patients undergoing percutaneous coronary interventions

BackgroundThe aim of the present study was to assess the influence of anemia on the risk of developing contrast-induced nephropathy after percutaneous coronary angioplasty.MethodsSerum creatinine values were measured before and within 48 h after the administration of contrast agents. Contrast-induced nephropathy (CIN) was defined as an increase of ≥0.5 mg/dl or ≥25 % in serum creatinine concentration over baseline within 48 h after administration. Anemia was defined as hemoglobin <120 g/l in women and <130 g/l in men.ResultsAmong the 1,026 patients studied, 32 (3.1 %) developed CIN after procedure. CIN occurred in 6.3 % of the anemic patients and in 2.2 % of the non-anemic patients (P < 0.01). The incidence of CIN increased with decreasing of baseline estimated glomerular filtration rate (eGFR) in both the anemia and non-anemia groups. In patients with baseline eGFR <30 ml/min, a high proportion of both anemic and non-anemic patients experienced CIN (24.6 vs. 17.5 %). When baseline eGFR was 30–59 ml/min, the incidence of CIN in anemic patients was twofold higher than in non-anemic patients (7.9 vs. 3.8 %; P < 0.05). Multivariate logistic regression analysis found that baseline eGFR and baseline hemoglobin were independent predictors of CIN.ConclusionAnemia is associated with a higher incidence of CIN in patients with moderate renal dysfunction. Patients with both preexisting renal insufficiency and anemia are at high risk of CIN. Baseline eGFR and baseline hemoglobin are independent predictors of CIN.

Risk of Contrast induced nephropathy in patients undergoing Primary coronary angioplasty

Background: Contrast induced nephropathy (CIN) is one of the common cause for hospital acquired renal failure in patients undergoing coronary angioplasty for acute myocardial infarction. The aim of this study was to assess the renal function in patients after primary coronary angioplasty by estimating the levels of serum creatinine (Sr. Cr) Materials and Methods: Sample sizes of 51 subjects were included for the study. Serum creatinine levels were measured before and after the procedure. The difference in Serum creatinine levels was calculated.CIN was defined as increase in Sr Cr &gt;0.5 or &gt;25% compared to the baseline value. Results: Out of the 51 cases, CIN occurred in 7.8% (4 cases). In addition,19.6 %( 10 cases) had pre-existing renal insufficiency out of which 3 subjects developed CIN.According to recently proposed

Similar Risk of Renal Events Among Patients Treated With Tenofovir or Entecavir for Chronic Hepatitis B

Tenofovir is a nucleotide reverse-transcriptase inhibitor approved for treatment of human immunodeficiency virus infection, as well as chronic hepatitis B (CHB). We evaluated nephrotoxicity among patients with CHB treated with tenofovir. We performed a community-based, retrospective cohort study of 80 patients with CHB who received tenofovir, alone or in a combination regimen; they were matched for age and sex with 80 CHB patients who received only entecavir. Incidences of serum creatinine (SCr) increase ≥0.2 mg/dL and new SCr levels of 1.5, 2.0, or 2.5 mg/dL were assessed. Patients with an estimated glomerular filtration rate (eGFR) <60 mL/min, calculated using the Modification of Diet in Renal Disease or Cockcroft-Gault formula, or who had ≥20% decrease in eGFR were also recorded. More patients given entecavir had increases in SCr ≥2.5 mg/dL (1 vs 6; P = .053), whereas more patients given tenofovir had a new Cockcroft-Gault eGFR of <60 mL/min (15 vs 6; P = .022) and at least 1 dose adjustment (13 vs 4; P = .021). By multivariate analysis, the only significant factors associated with an increase in SCr were a history of organ transplantation (adjusted odds ratio, 6.740; 95% confidence interval, 1.799-28.250; P = .005) and pre-existing renal insufficiency (adjusted odds ratio, 10.960; 95% confidence interval, 2.419-48.850; P = .002). No factors, including therapy assignment, were associated with a new eGFR <60 mL/min. Markers of renal function indicated that patients who received tenofovir were no more likely to have changes in renal function than patients treated with entecavir. History of transplant and pre-existing renal insufficiency were the only factors independently associated with increases in SCr.

Statins in prevention of contrast-induced nephropathy in patients with coronary heart disease and renal insufficiency undergoing percutaneous coronary intervention

Objective To explore the role of short-term, high-dose atorvastatin in the prevention of contrast-induced nephropathy ( CIN ) in patients with renal insufficiency after percutaneous coronary intervention ( PCI ).Methods 41 patients with coronary heart discease ( CHD ) and renal insufficiency underwent scheduled PCI.They received either 80 mg/d of atorvastatin ( study group,n =21 ),or 20 mg/d of atorvastatin ( control group,n =20 ) for 3 days before PCI.Serum creatinine ( SCr )levels were measured before and on days 1,2,and 3 after PCI.CIN was defined as an increase in SCr values of ≥ 25％ or ≥ 0.5 mg/dl from the baseline within 3 days after PCI.Results There were no significant differences in levels of SCr between the two groups at different time points ( P ＞ 0.05 ).The incidence rate of CIN did not differ significantly between the two groups ( one in each group,P＞ 0.05 ).There was no significant difference in the peak level of SCr between the study group and the control group after intervention ( 232.4 μmol/L vs.227.6 μmol/L,P＞ 0.05 ).Conclusions On the basis of standard intravenous hydration,a short-term administration of high doses of atorvastatin before and after contrast exposure fails to decrease CIN occurrence in CHD patients with pre-existing renal insufficiency. Key words: Statins; Contrast-induced nephropathy; Prevention

Endovascular aortic aneurysm repair with carbon dioxide-guided angiography in patients with renal insufficiency

Renal dysfunction following endovascular abdominal aortic aneurysm repair (EVAR) remains a significant source of morbidity and mortality. We studied the use of carbon dioxide (CO(2)) as a non-nephrotoxic contrast agent for EVAR. Recorded data from 114 consecutive patients who underwent EVAR with CO(2) as the contrast agent over 44 months were retrospectively analyzed. CO(2) was used exclusively in 72 patients and in an additional 42 patients iodinated contrast (IC) was given (mean, 37 mL). Renal and hypogastric artery localization and completion angiography were done with CO(2) in all patients, including additional arterial embolization in 16 cases. Preoperative National Kidney Foundation glomerular filtration rate (GFR) classification was normal in 16 patients, mildly decreased in 52, moderate to severely decreased in 44, and two patients were on dialysis. All graft deployments were successful with no surgical conversions. CO(2) angiography identified 20 endoleaks (two type 1, 16 type 2, and two type 4) and three unintentionally covered arteries. Additional use of IC in 42 patients did not modify the procedure in any case. When compared with a cohort of patients who underwent EVAR using exclusively IC, the operative time was shorter with CO(2) (177 vs 194 minutes; P = .01); fluoroscopy time was less (21 vs 28 minutes; P = .002), and volume of IC was lower (37 vs 106 mL; P < .001). Postoperatively, there were two deaths, two instances of renal failure requiring dialysis, and no complications related to CO(2) use. Among patients with moderate to severely decreased GFR, those undergoing EVAR with IC had a 12.7% greater decrease in GFR compared with the CO(2) EVAR group (P = .004). At 1, 6, and 12-month follow-up, computed tomography angiography showed well-positioned endografts with the expected patent renal and hypogastric arteries in all patients and no difference in endoleak detection compared with the IC EVAR group. During follow-up, eight transluminal interventions and one open conversion were required, and no aneurysm-related deaths occurred. CO(2)-guided EVAR is technically feasible and safe; it eliminates or reduces the need for IC use, may expedite the procedure, and avoids deterioration in renal function in patients with pre-existing renal insufficiency. A prospective trial comparing CO(2) with IC during EVAR is warranted.

Kardiorenales Syndrom

The cardiorenal syndrome describes the frequent clinical situation in which therapy of a patient with acute cardiac decompensation is limited by a decline of renal function. This is frequently associated with preexisting chronic renal insufficiency. It is important to be aware of this potentially fatal constellation and perform diuretic therapy slowly and carefully in order to avoid inadequate volume depletion. This may require surveillance in an intensive care unit. Ultrafiltration is an alternative to diuretic therapy which may permit greater fluid loss when beginning therapy and better control of volume reduction once heart failure symptoms improve. The individual treatment of patients with cardiorenal syndrome requires a close cooperation between cardiologists and nephrologists.

Clinical Results of Endovascular Abdominal Aortic Aneurysm Repair in Patients with Renal Insufficiency without Hemodialysis

Chronic renal insufficiency may be a relative contraindication to endovascular aneurysm repair (EVAR) for the use of contrast enhanced mediums. It is thought that more contrast enhanced media are needed in patients who are not anatomically suitable for EVAR, because of procedural difficulties. We reviewed a 2 year EVAR experience at our institution to determine whether the procedure and use of contrast enhanced mediums has any deleterious effect on renal function in patients with pre-existing chronic renal insufficiency. EVAR was performed in 46 patients with pre-existing chronic renal insufficiency without hemodialysis. Patients were retrospectively assigned to two groups on the basis of their preoperative creatinine clearance levels. Furthermore, patients were assigned to two other groups on the basis of anatomical suitability for EVAR. The absolute change in the serum creatinine (Cr) level was reviewed in the each renal insufficiency group between the preoperative and post-operative time periods. No increase in the serum Cr level was noted, and no patient required temporary or permanent hemodialysis, in any of the groups. EVAR with contrast agents can be accomplished in patients with chronic renal insufficiency without hemodialysis; therefore,elevated Cr levels maynot be a contraindication in EVAR.

IJU this issue

This issue contains two Editorials, one Review article, three Original articles, one Case Report, three Short Communications, and two Letters to the Editor. This issue starts with an Editorial by Professor Razack (Kuala Lumpur, Malaysia). Professor Razack, of the University of Malaya, describes the history and current status of urology in Malaysia. The Malaysian Urological Association (MUA) was founded in 1974, and aims to strengthen closer links within Asia and rest of the world's urological communities. Urology in Malaysia had made great strides since its humble start in the late 1960s to its current status, in which most of the latest equipment and facilities are available within the country. There are three da Vinci robots in the country and many laser machines for both treatment of stones and prostate diseases. MUA continues to look for opportunities to host international conferences and meetings. The review by Kitajima et al. (Kobe, Japan) describes recent issues in contrast-induced nephropathy (CIN). CIN is a serious complication among patients undergoing contrast-enhanced computed tomography with potentially high morbidity and mortality. Patients with pre-existing renal insufficiency appear to be at higher risk of CIN. To prevent CIN, every effort is required, including the routine identification of at-risk patients, the use of appropriate hydration regimens, the withdrawal of nephrotoxic drugs, the selection of a low-osmolality or iso-osmolar contrast medium (CM), and using the minimum volume of CM possible Cao et al. (Qingdao, China) determine whether steroidogenic enzyme expression is associated with the steroid secretory pattern of subclinical Cushing's syndrome (SCS) by investigating the mRNA and protein expression of CYP17 and CYP11B1 in SCS adenomas. They found that CYP11B1 and CYP17 are overexpressed in subclinical cortisol-producing adenomas (CPA) and their overexpression accounts for the increased production of cortisol that is characteristic of CPA. Gacci et al. (Florence, Italy) report factors predicting the recovery of continence after a radical prostatectomy (RP). They found that preoperative erectile function can predict post-prostatectomy incontinence, and bladder neck preservation has a significant effect on early continence recovery after RP. Kobayashi et al. (Sapporo, Japan) report an animal model for erectile dysfunction (ED) following lower urinary tract symptoms (LUTS) and bladder outlet obstruction (BOO). Male Sprague–Dawley rats with partial BOO are an experimental model of LUTS and ED. The partial-BOO rats show decreased erectile function due to endothelial dysfunction induced by impaired eNOS function. Sugimoto et al. (Saga, Japan) report a rare case of a ureterosciatic hernia successfully treated by a ureteral placement. Non-enhanced computed tomography reveals left hydroureteronephrosis and obstruction of the distal left ureter with herniation into the sciatic foramen. After 2 months with treatment with the stent, there was no recurrence. The three Short Communications are of great interest. Suzuki et al. (Tokyo, Japan) analyze the results of direct decompressive surgery plus stabilization of the vertebrae involved in six non-ambulatory patients with metastatic extradural spinal cord compression due to renal cell carcinoma. Tanaka et al. (Tokyo, Japan) evaluate diffusion-weighted magnetic resonance imaging in differentiating between minimal fat angiomyolipoma and clear cell renal cell carcinoma. Kozyrakis et al. (Athens, Greece) report on their experience with six patients diagnosed with lymphoepithelioma-like bladder carcinoma over the past 15 years. The Letter to the Editor from Nomiya et al. (Tokyo, Japan) report the first Japanese case of interstitial cystitis (IC) symptoms associated with ketamine abuse. Ketamine abuse should be included in the differential diagnoses for those presenting with LUTS suggestive of IC. The Letter to the Editor from Adam (Pretoria, South Africa) describes a message about an article by Ochiai et al. (International Journal of Urology 2011; 18: 200–5). He points out importance of combination threshold values for the PCA3 assay and prostate-specific antigen (PSA) levels, or a normal digital rectal examination (DRE), or both, to identify the presence of cancer. In their cohort study, a PCA3 score <60 associated with a PSA level <4 ng/mL and a normal DRE excluded the presence of cancer on histology. None declared.

Recent issues in contrast‐induced nephropathy

Contrast-induced nephropathy (CIN) is a serious complication resulting from the use of iodinated contrast medium (CM) with potentially high morbidity and mortality. Patients with pre-existing renal insufficiency appear to be at higher risk of CIN. To prevent CIN among patients undergoing contrast-enhanced computed tomography, every effort is required, including routine identification of at-risk patients, the use of appropriate hydration regimens, withdrawal of nephrotoxic drugs, selection of low-osmolality CM or iso-osmolar CM, and using the minimum volume of CM possible.

Systolic blood pressure at Emergency Department presentation and 1-year mortality in acute chest pain patients

Background High blood pressure at rest has been an established risk factor for cardiovascular disease. However the relationship between Systolic Blood Pressure (SBP) and 1-year-mortality among acute chest pain patients presenting to Emergency Department (ED); and effects of preexisting renal insufficiency, hemodynamic stress — as quantified by Brain Natriuretic Peptide (BNP) and chest pain duration, on this relationship is unknown. Methods Data was used from APACE (Advantageous Predictors of Acute Coronary Syndrome Evaluation), a prospective observational multicenter study of 1240 ED chest pain patients. SBP at presentation was categorized into quartiles: Q1 ≤ 127 mm Hg; Q2 128–142 mm Hg; Q3 143–160 mm Hg; Q4 ≥ 161 mm Hg. Results 60 deaths occurred during 1-year. One-year-mortality-rate showed lower Hazard Ratios for Q2, Q3 and Q4 vs Q1 (HR [95% CI]; 0.39 (0.19–0.78), 0.34 (0.17–0.70), 0.35 (0.17–0.72); p < 0.01 respectively). Cox model adjusted for various demographic and treatment variables showed that participants in Q3 and Q4 had better prognoses than Q1. Patients showed progressively better prognosis from Q2 through Q4 vs Q1 only in patients who presented to ED with for more than 12 h of chest pain duration. Patients with renal insufficiency had lower SBP at presentation than others (p = 0.001). There was no association between the outcome and interaction variable of SBP quartiles and BNP (p = 0.27). Conclusion Acute chest pain patients presenting to ED exhibit an inverse association between SBP at presentation and 1-year-mortality; a relationship which appears stronger in those who present with chest pain of greater than 12 h duration.

Baseline incidence and severity of renal insufficiency evaluated by estimated glomerular filtration rates in patients scheduled for contrast-enhanced CT

Although pre-existing renal insufficiency (RI) is the most important risk factor for contrast-induced nephropathy (CIN), the background distribution of baseline renal function has not been investigated thoroughly in patients scheduled for contrast-enhanced CT. To investigate the incidence and severity of baseline RI evaluated by estimated glomerular filtration rates (eGFR) in patients who underwent contrast-enhanced CT at an academic center. A total of 6586 patients (3630 men and 2956 women; mean age 57.0 ± 11.9 years) who underwent contrast-enhanced CT between January and December 2008 were retrospectively studied. Of these, 829 had cardiovascular diseases (CVD), 5116 had oncologic diseases, 178 had diabetes mellitus (DM), and 1572 had chronic liver disease (CLD). The eGFR (mL/min/1.73 m(2)) was calculated from their serum creatinine level. Mild, moderate-a, moderate-b, and severe RI were recorded at 60 < =eGFR < 90, 45 < =eGFR < 60, 30 < =eGFR < 45 and eGFR < 30, respectively. Of the 6586 patients, 1.6%, 3.7%, 13.7%, and 54.2% were judged to present with severe, moderate-b, moderate-a, and mild RI, respectively. While moderate-b-to-severe RI was recorded in 133 (3.2%) of 4161 patients aged 70 years or less, it was observed in 218 (9.0%) of the 2425 patients who were 71 years or older. Among the 829 CVD patients, 9.9% manifested moderate-b-to-severe- and 73.0% mild-to-moderate-a RI. The corresponding rates were 4.4% and 68.9% for oncologic disease, 16.9% and 61.2% for DM, and 4.8% and 71.5% for CLD patients. By univariate analysis, there was a significant association between moderate-b-to-severe RI and the advanced age, CVD, DM, and non-oncologic disease. Multivariate analysis showed that the advanced age, DM, and non-oncologic disease were statistically associated with moderate-b-to-severe RI. The incidence of RI of eGFR < 45mL/min/1.73 m(2) at baseline was high in patients with advanced age, CVD and DM and in patients without oncologic disease.

Evaluation and Management of Peripheral Vascular Injury. Part 1. Western Trauma Association/Critical Decisions in Trauma

This is a position article from members of the Western Trauma Association (WTA). Because there are no prospective randomized trials on the evaluation and management of peripheral vascular trauma, the algorithm (Fig. 1) is based on the expert opinion of WTA members and published observational studies. It may not be applicable at all hospitals caring for injured patients. The algorithm contains letters that correspond to lettered text that is intentionally concise. This Part I algorithm emphasizes evaluation, diagnosis, and need for operation versus a therapeutic procedure performed in interventional radiology, while a Part II algorithm (2011) will focus on operative techniques. Peripheral vascular injures defined as axillobrachial and branches in the upper extremity and femoropopliteal and branches in the lower extremity account for 40% to 75% of all vascular injuries treated in civilian trauma centers.1–4 With the exception of the axillary artery, the long tracks of named arteries and veins in the extremities make them particularly susceptible to either penetrating or blunt trauma. This fact coupled with the smaller diameter of many of these vessels (as compared with those in the thorax or abdomen) and the ability of the patient and others to control external hemorrhage with compression contribute to a low incidence of death in the field.

Acute renal failure due to tobramycin intoxication during selective digestive tract decontamination

Dear Editor, A 52-year-old man was admitted to the intensive care unit (ICU) with septic shock due to pneumonia. Two months before he had an oesophago-gastrectomy because of carcinoma of the distal part of the oesophagus. The post-operative course was complicated because of ischaemic lesions in the transverse colon and suture dehiscence of the ileotransversostomy. An ileostomy and colostomy were constructed (Fig. 1). Fig. 1 Schematic drawing of patient’s changed anatomy after surgery. Resection of esophagus and stomach, replaced by a colon segment with a Roux-Y reconstruction. After suture dehiscence of the ileotransversostomy the suture was opened, transversectomy ... Apart from antibiotic treatment, he received selective decontamination of the digestive tract (SDD) as described previously by De Smet et al [1]. SDD was administered four times daily as a 2% oral paste, containing amphotericin B, tobramycin and colistin. Four times daily a 10 ml (containing 500 mg amphotericin B, 100 mg colistin, 80 mg tobramycin) suspension was given nasogastrically. Additionally, twice daily a suppository (containing 500 mg amphotericin B, 40 mg tobramycin, 100 mg colistin) was administered in the colostomy of the descending colon. He recovered but because of ICU-acquired weakness he needed prolonged mechanical ventilation. Thirty days after admission he became oliguric and developed renal failure with renal acidosis without further clinical signs of haemodynamic instability. His creatinine level gradually increased from 50 to 263 μmol/l. Physical, laboratory and radiological examination ruled out sepsis, hypovolaemia and post-renal obstruction. Medication-induced nephrotoxicity was suspected. Serum tobramycin level was elevated (18.9 mg/l). SDD was discontinued. After haemodialysis and veno-venous haemofiltration tobramycin levels became undetectable again. However, renal insufficiency persisted and he remained dependent on dialysis. Elevated serum tobramycin levels during SDD have been shown in patients with normal renal function and pre-existent renal insufficiency [2, 3]. Several mechanisms might explain increased serum levels of non-absorbable antimicrobial agents in this patient. First, the integrity of the mucosal barrier might have been compromised by the initial sepsis causing increased permeability for tobramycin [4]. Secondly, our patient was malnourished as a result of chronic illness and frequent periods of retention of enteral feeding. Malnutrition is associated with increased movements of large molecules through the paracellular tight junction in jejunal epithelia [5]. Thirdly, our patient had a blinded jejunal loop which could act as reservoir for tobramycin. The amphotericin B levels were not measured but could also be increased. The nephrotoxic effect of parenteral administration of amphotericin B is well known. No other medication could explain the acute renal failure. This case indicates that patients with altered abdominal anatomy and/or perforations and/or malnutrition might be at risk to develop nephrotoxicity from SDD, especially when SDD is administered via several routes. Besides the current debate about the effects of SDD on antibiotic resistance, no complications of tobramycin-related toxicity are reported in more than 50 randomized controlled trials. Future studies on SDD should also incorporate such safety analyses.

Rapid deterioration of renal insufficiency after magnetic resonance imaging with gadolinium-based contrast agent

Gadolinium (Gd)-based contrast media were introduced as alternatives to iodinated media for magnetic resonance imaging (MRI). Although originally thought to be non-nephrotoxic, Gd-based contrast media have recently been reported to be associated with acute kidney injury. The underlying mechanism of Gd-induced renal injury is not completely understood. We report an 80-year-old patient with buccal mucosa cancer for whom MRI with Gd-based contrast agent was conducted 3 times within 3 weeks. The patient developed rapid deterioration of preexisting renal insufficiency, and developed uremic symptoms and pulmonary edema. The patient was hemodialyzed 3 times. This resulted in improvement of renal function and clinical symptoms. This case emphasizes the potential nephrotoxicity of Gd-based contrast media and suggests that renal insufficiency, diabetes mellitus, old age and high dose of Gd-based contrast medium are risk factors for acute kidney injury.

Emergency thoracic surgery in elderly patients

ObjectivesEmergency thoracic surgery in the elderly represents an extreme situation for both the surgeon and patient. The lack of an adequate patient history as well as the inability to optimize any co-morbidities, which are the result of the emergent situation, are the cause of increased morbidity and mortality. We evaluated the outcome and prognostic factors for this selected group of patients.DesignRetrospective chart review.SettingAcademic tertiary care referral center.ParticipantsEmergency patients treated at the Department of Thoracic Surgery, University Hospital of Luebeck, Germany.Main outcome measuresCo-morbidities, mortality, risk factors and hospital length of stay.ResultsA total of 124 thoracic procedures were performed on 114 patients. There were 79 men and 36 women (average age 72.5 ±6.4 years, range 65–94). The overall operative mortality was 25.4%. The most frequent indication was thoracic/mediastinal infection, followed by peri- or postoperative thoracic complications. Risk factors for hospital mortality were a high ASA score, pre-existing diabetes mellitus and renal insufficiency.ConclusionsOur study documents a perioperative mortality rate of 25% in patients over 65 who required emergency thoracic surgery. The main indication for a surgical intervention was sepsis with a thoracic/mediastinal focus. Co-morbidities and the resulting perioperative complications were found to have a significant effect on both inpatient length of stay and outcome. Long-term systemic co-morbidities such as diabetes mellitus are difficult to equalize with respect to certain organ dysfunctions and significantly increase mortality.

Renal Function Outcomes After Laparoscopic Renal Cryoablation

Laparoscopic cryoablation (LCA) has emerged as an alternative to conventional surgery for the management of a T(1) renal mass; however, only few data are available on its functional outcomes. We assessed renal function changes after LCA in patients with normal renal function (NRF) and preexisting chronic renal insufficiency (CRI). Data of consecutive patients who were undergoing LCA between 2000 and 2008 at Duke University Medical Center were analyzed. Renal function parameters were obtained preoperatively, at discharge, and at 6, 12, and 24 months postoperatively. Serum creatinine (sCr) levels and estimated glomerular filtration rates (eGFR) were compared over a 2-year follow-up. Of 67 patients, 22 (33%) had CRI at baseline. These patients were older, had larger tumors (2.5 vs 2.0 cm, P=0.039), and a higher incidence of multiple lesions (22.7% vs 4.4%, P=0.034). Compared with baseline, sCr was significantly increased and eGFR declined at discharge, 6, 12, and 24 months in both NRF and CRI groups. Median sCr increase was 0.1 mg/mL, eGFR declined by 4.2 mg/mL/1.73 m(2) in the CRI cohort and up to 8.8 mg/mL/1.73m(2) in NRF patients (all P<0.05) during the follow-up. Compared with baseline, however, no significant changes were noted in the distribution of CRI categories at any time (all P>0.05). A minimal decline in renal function can be appreciated in patients undergoing LCA at midterm follow-up. This decline is no higher in CRI than in NRF patients. LCA offers excellent renal function outcomes at 2 years follow-up. Specifically, in patients with CRI, LCA offers excellent preservation of renal function.