ED presentations of acute renal infarction

Acute Renal Infarction: A 12-Year Retrospective Analysis

INTRODUCTION

Acute renal infarction (ARI) is a relatively rare and underdiagnosed condition. Presenting symptoms are nonspecific, and imaging is the mainstay for diagnosis. This study attempts to characterize the profile of patients with ARI and identify possible risk factors.

METHODS

All inpatients admitted with diagnosis of ARI between 2010 and 2022 were included in this single-center retrospective observational study. Patients with chronic renal infarction, iatrogenic causes, and without radiographic evidence of ARI were excluded. Clinical, laboratory, and radiological findings of patients were collected. Patients were grouped into three groups based on probable etiology: cardiovascular, hypercoagulable disorders, and idiopathic, and analyzed.

RESULTS

Eighty-five patients were included. Mean age of patients was 61.6 ± 17.54 years. Cardiovascular group had the highest number of patients (49.4%) of which atrial fibrillation was the most common etiology (59.5%). Malignancy was the most common etiology in the hypercoagulable disorder group (69.3%). Patients in the idiopathic group were significantly younger and had higher mean body mass index than the other 2 groups at presentation. Smokers had 9 times higher risk of renal infarction in cardiovascular group and 1.7 times higher risk in hypercoagulable when compared to the idiopathic group. 48.2% of patients developed renal infarction though they were on antiplatelets/anticoagulants.

CONCLUSION

ARI is a rare and often underdiagnosed condition that can have residual renal dysfunction. It is important to consider ARI as a differential especially in young patients with risk factors even if they are on anticoagulation medication.

A Case of Recurrent Renal Infarction Following Transient Resolution: Evidence From Serial Computed Tomography

Although renal infarction (RI) is not a rare disease, its outcomes have not been well-documented. Furthermore, transient resolution and recurrence of RI have not been captured through imaging. We report a case of idiopathic RI that recurred within a short period following transient resolution, as demonstrated by serial computed tomography (CT). A 53-year-old man diagnosed with RI was transferred to the emergency room. An abdominal CT scan at the local hospital revealed a segmental wedge-shaped perfusion defect in the left kidney and a focal thrombotic filling defect in the anterior segmental branch of the left renal artery. Since his left flank pain improved, another CT scan was performed again 6 hours after the initial CT scan. A repeat CT scan showed that the thrombus in the renal artery remained, but the perfusion defect had spontaneously resolved. We initiated anticoagulant therapy using unfractionated heparin. On the sixth day of hospitalization, the left flank pain recurred, prompting another CT scan. The follow-up CT scan confirmed that RI had recurred in the same area as before. We continued anticoagulant therapy and switched to warfarin. After treatment, his symptoms improved, and he was discharged. RI can recur at any time, even after it has spontaneously resolved, as evidenced by our case. Therefore, it is crucial to closely monitor patients who experience resolution of RI for any recurrence of symptoms, and repeat radiological evaluation should be performed even within a short period.

A Case Report of Renal Infarcts Secondary to Segmental Arterial Mediolysis

Flank pain is an exceptionally common presenting symptom in the emergency and primary care setting; however, most clinicians may not include a differential diagnosis of renal infarct (RI) due to the reported low incidence of this condition. Delayed diagnosis or treatment intervention for RI can have dire consequences for the patient including hypertension and longstanding renal impairment. In this report, we review a case of a previously healthy 39-year-old male presenting with flank pain, which after extensive workup, was revealed to be caused by renal infarction from a renal artery dissection secondary to segmental arterial mediolysis (SAM).

Bilateral Renal Infarct in a Young Adult: Unveiling an Autoimmune Enigma

A man in his late 20s presented to the emergency department with sudden-onset abdominal pain. Urinalysis was significant for hematuria and slightly elevated creatinine. A computed tomography (CT) scan with IV contrast revealed bilateral renal infarcts, which was corroborated by a computed tomography angiogram (CTA). Further evaluation by an autoimmune panel demonstrated a positive antinuclear antibody, while echocardiography showed left ventricular non-compaction cardiomyopathy. The workup included consultations with multiple specialities and additional investigations to assess hypercoagulability, vasculitis, and infectious etiologies. Following supportive care, the patient was discharged in stable condition with a plan for outpatient follow-up and further workup, including screening of first-degree family members for left ventricular non-compaction and associated cardiovascular risks. Here we describe a report of a rare case of bilateral renal infarct of possible thromboembolic etiology due to an underlying rare genetic cardiovascular condition.

Prolonged hiccups induced by renal infarction: a case report

BACKGROUND

Hiccups are common symptoms that last for less than 48 hours. However, we encountered a case of renal infarction in a patient with prolonged hiccup. The relationship between hiccups and renal infarction is important in differentiating patients with prolonged hiccups.

CASE PRESENTATION

An 87-year-old Japanese man with atrial fibrillation and receiving antithrombotic therapy presented to the emergency department with prolonged hiccups. The patient discontinued antithrombotic therapy for atrial fibrillation due to subcortical bleeding, after which he experienced right back pain. He was diagnosed with right renal infarction based on computed tomography images, and the antithrombotic therapy was continued. The patient's hiccups ceased, and he was discharged on hospital day 11.

CONCLUSION

Hiccups can be induced by various clinical conditions. It is hypothesized that the inflammation of the right kidney infarction stimulated the diaphragm and induced prolonged hiccups in this patient; this theory is supported by the computed tomography images. This case report shows that internal organ diseases irritating the diaphragm can cause hiccups, and renal disease should be considered in patients with prolonged hiccups.

Renal Artery Thrombosis After Laparoscopic Living-Donor Nephrectomy: A Case Report

Renal transplantation is the most successful treatment for end-stage renal disease, and the number of living-donor nephrectomies has been rising over the years due to the advantages it offers over deceased donors. Although this surgery is considered safe, it can be associated with complications amplified by the fact that it is performed on a healthy individual. Renal artery thrombosis is a rare disease that needs prompt diagnosis and treatment to avoid renal function deterioration, which becomes even more important in cases of solitary kidneys. We report the first case of renal artery thrombosis after laparoscopic living-donor nephrectomy treated with catheter-directed thrombolysis.

Clinical factors distinguishing renal infarction from acute pyelonephritis: A randomly matched retrospective case-control study

INTRODUCTION

Renal infarction (RI) is rare but clinically important because the appropriate treatment depends on the time of diagnosis. RI is often misdiagnosed as acute pyelonephritis (APN) because both diseases have nonspecific symptoms such as flank pain and abdominal pain. We identified predictors for distinguishing RI from APN.

METHODS

The data of patients visited the emergency department and diagnosed with RI or APN from March 2016 to May 2020 were prospectively collected and retrospectively analyzed. Patients aged under 18 years, with a history of trauma, or incomplete medical records were excluded. Using a matching ratio of 1:5, RI patients were randomly matched to APN patients. Multivariable logistic regression analysis was performed to identify factors that could distinguish RI from APN. In addition, we constructed a decision tree to identify patterns of risk factors and develop prediction algorithms.

RESULTS

The RI and APN groups included 55 and 275 patients, respectively. Multivariable logistic regression analysis showed that male sex (OR, 6.161; p = 0.009), atrial fibrillation (AF) (OR, 14.303; p = 0.021), costovertebral angle tenderness (CVAT) (OR, 0.106; p < 0.001), aspartate transaminase (AST) level > 21.50 U/L (OR, 19.820; p < 0.001), C-reactive protein (CRP) level < 19.75 mg/L (OR, 10.167; p < 0.001), and pyuria (OR, 0.037; p < 0.001) were significantly associated with RI distinguishing from APN.

CONCLUSION

Male sex, AF, no CVAT, AST level > 21.50 U/L, CRP level < 19.75 mg/L, and no pyuria were significant factors that could distinguish RI from APN.

Temporal Trend of the Incidence and Characteristics of Renal Infarction: Korean Nationwide Population Study

BACKGROUND

Large-scale studies about epidemiologic characteristics of renal infarction (RI) are few. In this study, we aimed to analyze the incidence and prevalence of RI with comorbidities in the South Korean population.

METHODS

We investigated the medical history of the entire South Korean adult population between 2013 and 2019 using the National Health Insurance Service database (n = 51,849,591 in 2019). Diagnosis of RI comorbidities were confirmed with International Classification of Disease, Tenth Revision, Clinical Modification codes. Epidemiologic characteristics, distribution of comorbidities according to etiologic mechanisms, and trend of antithrombotic agents were estimated.

RESULTS

During the 7-years, 10,496 patients were newly diagnosed with RI. The incidence rate increased from 2.68 to 3.06 per 100,000 person-years during the study period. The incidence rate of RI increased with age peaking in the 70s with 1.41 times male predominance. The most common comorbidity was hypertension, followed by dyslipidemia and diabetes mellitus. Regarding etiologic risk factor distribution, high embolic risk group, renovascular disease group, and hypercoagulable state group accounted for 16.6%, 29.1%, and 13.7% on average, respectively. For the antithrombotic treatment of RI, the prescription of antiplatelet agent gradually decreased from 17.0% to 13.0% while that of anticoagulation agent was maintained around 35%. The proportion of non-vitamin K antagonist oral anticoagulants remarkably increased from only 1.4% to 17.6%.

CONCLUSION

Considering the progressively increasing incidence of RI and high prevalence of coexisting risk factors, constant efforts to raise awareness of the disease are necessary. The current epidemiologic investigation of RI would be the stepping-stone to establishing future studies about clinical outcomes and optimal treatment strategies.

Rare renal embolic manifestation of left atrial myxoma: A case report

INTRODUCTION AND IMPORTANCE

A complete occlusion of the renal artery due to atrial myxoma is a rare occurrence.

CASE PRESENTATION

Here we present a case of a completely occluded left renal artery caused by atrial myxoma emboli that presented with a 14-hour history of sudden onset sharp left flank pain radiating to the left lower quadrant of the abdomen, nausea, with preserved kidney function. Revascularization is unlikely to benefit the patient because it has been more than 6 h since the onset of ischemia. Anticoagulation therapy was initiated, followed by myxoma resection. The patient was discharged with no evidence of nephropathy.

CLINICAL DISCUSSION

Anticoagulation with or without thrombolysis is the standard treatment strategy for renal artery embolism. Given the delayed presentation of renal artery occlusion and the nature of the embolism, revisualization is not beneficial for this case.

CONCLUSION

Emboli of atrial myxoma caused renal artery occlusion is rare. Thrombolysis or surgical revascularization can be used to restore perfusion for renal artery embolism. However, the likelihood of benefit from revascularization must be assessed.

Predictors for Distinguishing Renal Infarction From Urolithiasis in the Emergency Department: A Randomly Matched Retrospective Case-Control Study

BACKGROUND

Emergency department (ED) clinicians may misdiagnose renal infarction (RI) as urolithiasis because RI is a rare disease with presenting symptoms similar to the symptoms of urolithiasis. However, earlier diagnosis of RI can improve patient prognosis.

OBJECTIVES

We investigated potential predictors for distinguishing RI from urolithiasis based on clinical findings and laboratory results.

METHODS

This randomly matched retrospective case-control study included patients who had been diagnosed with acute RI or acute urolithiasis between January 2016 and March 2020. Patients were excluded if they were aged under 18 years, had a history of trauma, or had incomplete medical records. Using a matching ratio of 1:4, RI patients were randomly matched to urolithiasis patients. Multivariable logistic regression was performed to identify factors that could distinguish RI from urolithiasis.

RESULTS

In total, 48 patients were included in the RI group and 192 patients were included in the urolithiasis group. Multivariable logistic regression showed that age ≥ 65 years (odds ratio [OR] 6.155; p = 0.022), atrial fibrillation (OR 18.472; p = 0.045), current smoking (OR 17.070; p = 0.001), costovertebral angle tenderness (OR 0.179; p = 0.037), aspartate aminotransferase level ≥ 27.5 U/L (OR 6.932; p = 0.009), sodium level ≥ 138.5 mEq/L (OR 0.079; p = 0.004), and hematuria (OR 0.042; p = 0.001) were significant predictors that could distinguish RI from urolithiasis. Based on these results, a nomogram was constructed.

CONCLUSION

Age ≥ 65 years, atrial fibrillation, current smoking, absence of costovertebral angle tenderness, aspartate aminotransferase level ≥ 27.5 U/L, sodium level < 138.5 mEq/L, and absence of hematuria were predictors that can distinguish between RI and urolithiasis.

Efficacy of direct oral anticoagulant for renal infarction due to pulmonary vein stump thrombosis after left pneumonectomy

Background

Thrombosis of the pulmonary vein stump is a common complication after a left upper lobectomy and can be a source of embolism in various organs, such as the kidneys. A renal infarction, on the other hand, is a rare and often lethal condition that is usually diagnosed postmortem. Here, we present a case of renal infarction associated with pulmonary vein stump thrombosis after a left pneumonectomy, which was treated successfully with edoxaban.

Case presentation

A 73-year-old man was diagnosed with squamous cell lung cancer (cT1miN0M0 stage IA1). Due to pneumoconiosis, extensive lymph node infiltration into the pulmonary artery was noted and necessitated an open thoracotomy. Ultimately, a left pneumonectomy was performed. Atrial fibrillation occurred on postoperative day 3, and the patient complained of left-sided abdominal pain. Contrast-enhanced computed tomography revealed a left upper pulmonary vein thrombosis and a left renal infarction. Anticoagulant therapy was immediately initiated with heparin and warfarin. On postoperative day 13, warfarin was replaced with the direct oral anticoagulant edoxaban since the patient’s compliance and drug response to warfarin were poor. On postoperative day 19, contrast-enhanced computed tomography revealed a reduction in pulmonary vein stump thrombosis and improvement in renal infarction. Subsequently, the patient was discharged. Three months post-surgery, no infarct lesions or reduced renal function was observed on imaging.

Conclusions

The direct oral anticoagulant edoxaban could be effective in preventing recurrence or exacerbation of pulmonary vein thrombosis associated with renal infarction without bleeding complications.

FDG PET/CT Imaging Findings of Renal Infarction in a Patient With Gastric Adenocarcinoma

ABSTRACT

We report the FDG PET/CT findings of renal infarction in a 75-year-old woman patient who received chemotherapy for gastric adenocarcinoma. The patient was referred to our hospital for the evaluation of her response to chemotherapy. PET/CT detected circumferential increased FDG uptake in the outer part of the left renal cortex. The remaining of the renal cortex was photopenic. Abdominal CT angiography showed no contrast enhancement within the renal parenchyma. There was no contrast enhancement in the lumen of the left renal artery. These findings were thought to be consistent with the left renal infarct due to the occlusion of the left renal artery.

Case Report: Acute Renal and Splenic Infarctions Secondary to Atrial Fibrillation

Acute renal and splenic infarctions are an uncommon condition that can result from obstruction or decrease of renal and splenic arterial flow. We described a 73-year-old woman who presented with right flank pain and nocturnal dyspnea. The computed tomography (CT) scan with intravenous contrast showed multiple infarcts in both bilateral kidneys and spleen. Serum creatinine clearance was impaired. Further investigation by electrocardiogram (ECG) and 24-h Holter revealed that the patient had paroxysmal atrial fibrillation (PAF). Transthoracic and transesophageal echocardiographic findings were unremarkable except for severe spontaneous echo contrast (SEC) in the left atrial appendage. The development of thromboembolic renal and splenic infarction was attributed to embolism caused by atrial fibrillation. Anticoagulant therapy was initiated with low molecular weight heparin (LMWH) and followed by an oral anticoagulant. To manage PAF and prevent further embolism, the “One-stop” procedure, including atrial fibrillation catheter ablation and left atrial appendage occlusion (LAAO), was applied to this patient. Follow-up at 1 month showed normal sinus rhythm, improved renal function, and relieved renal and splenic infarction.

Influence of Tangeretin on the Exponential Regression of Inflammation and Oxidative Stress in Streptozotocin-Induced Diabetic Nephropathy

Diabetes is an amalgamation of metabolic disorders marked by hyperglycemia. Over time diabetes brings up several other complications with it like cardiovascular disease, retinopathy, neuropathy, and nephropathy. among which diabetic nephropathy (DN) is the one we are concerned about in the present study. Diabetes management requires following a healthy lifestyle with proper medication. Most of the anti-diabetic drugs available at present come with adverse side effects. Nature has provided us with several components that are anti-diabetic in nature which has fewer or no side effects and tangeretin is one among them. Tangeretin is a natural flavonoid abundantly present in orange peel and tangerines. Our study is designed to evaluate tangeretin, as an anti-diabetic medication especially for patients suffering from diabetic nephropathy. The procured healthy rats were first divided into four groups: the group I was maintained as healthy control and the others were subjected to the induction of diabetes by i.p. injection of streptozotocin (STZ) at the concentration of 55mg/kg b.wt .Then, the diabetic rats were further divided into three groups: group II was used as the diabetic control rats and the group III and group IV were administered with tangeretin (25mg/kg b.wt) and positive control drug metformin (150mg/kg b.wt) for 8 weeks. The body weight, blood glucose, and serum insulin levels were estimated at week 0 and week 8. Reactive oxygen species (ROS) inhibitory effect, antioxidant, antilipidemic, nephroprotective, and anti-inflammatory effects of tangeretin on the diabetic-induced rats were evaluated at the end of week 8 in addition to the histopathological assessment of the sections of the kidneys of the experimental rats. All the test results concluded that tangeretin was able to significantly decelerate the progression of DN in STZ-induced diabetic rats.

Endovascular Thrombus Aspiration and Catheter-Directed Thrombolysis for Acute Thromboembolic Renal Artery Occlusion

PURPOSE

We report a case of revascularization for an occluded renal artery using endovascular renal thrombus aspiration followed by catheter-directed thrombolysis.

CASE REPORT

A 56-year-old man presented with sudden onset severe left-sided abdominal and loin pain for 6 hours. Urgent computed tomography (CT) angiogram showed occlusion of left renal artery. Emergency selective left renal angiogram and thrombus aspiration using a 5-French Cobra catheter was performed. Catheter-directed thrombolysis with urokinase was initiated after aspiration thrombectomy. Angiogram 24 hours after thrombolysis showed the left renal artery and its segmental branches were successfully revascularized. Patient was put on anticoagulation after operation and his renal function recovered well.

CONCLUSION

Percutaneous aspiration thrombectomy with conventional catheters combined with intra-arterial local fibrinolysis could be used to salvage the renal function in case of complete renal artery thromboembolic occlusion.

Predictors of renal infarction in patients presenting to the emergency department with flank pain: A retrospective observational study

Objectives

Flank pain is a common symptom in the emergency department and can be caused by a variety of diseases. Renal infarction (RI) is a very rare disease, and many RI patients complain of flank pain. However, there is no definitive predictor of RI when patients complain of flank pain. This study aimed to identify the clinical factors for predicting RI in patients with flank pain.

Methods

This retrospective single-center study was conducted on patients complaining of flank pain from January 2016 to March 2020 at a South Korean tertiary care hospital. Exclusion criteria included patients who did not undergo contrast-enhanced computed tomography, age < 18 years, and trauma. Demographic and laboratory data were obtained from medical records. Logistic regression analysis was conducted to identify predictors of RI occurrence.

Results

In all, 2,131 patients were enrolled, and 39 (1.8%) had RI. From a multivariable logistic regression analysis, an age ≥ 65 years (odds ratio [OR], 3.249; 95% confidence interval [CI], 1.366–7.725; p = 0.008), male sex (OR, 2.846; 95% CI, 1.190–6.808; p = 0.019), atrial fibrillation (OR, 10.386; 95% CI, 3.724–28.961; p < 0.001), current smoker (OR, 10.022; 95% CI, 4.565–22.001; p < 0.001), and no hematuria (OR, 0.267; 95% CI, 0.114–0.628; p = 0.002) were significantly associated with the occurrence of RI.

Conclusions

Five clinical factors, i.e., age ≥ 65 years, male sex, atrial fibrillation, current smoker, and no hematuria, were significantly associated with the occurrence of RI in patients with flank pain.

Resistant hypertension after renal infarction in a man with fibromuscular dysplasia

We report the case of 39-year-old Caucasian man presenting in emergency department with new onset of severe hypertension with hypokalaemia eight weeks after renal colic. Patient was referred to a hypertension unit for further investigation. Hormonal analysis confirmed secondary aldosteronism and slightly impaired kidney function. Imaging revealed smaller right kidney, 'string of beads appearance' of distal part of right renal artery, a short zone of dissection and renal infarction. Renal scintigraphy showed significant blood flow reduction and severe functional damage of the right kidney. Despite multidrug antihypertensive treatment patient's hypertension was resistant and target organ damage evolved. After initial patient's refusal, he was later successfully treated with laparoscopic simple nephrectomy. Histopathological analysis confirmed renal artery dissection and medial fibroplasia. Thereafter, hypertension was controlled with trandalopril monotherapy. This is a first case report of the patient with renovascular multifocal fibromuscular dysplasia, dissection and renal infarction whose diagnosis of the disease was confirmed by angiography and histopathologic analysis. Resistant hypertension was successfully treated with nephrectomy.

Atrial fibrillation and kidney function: a bidirectional Mendelian randomization study

AIMS

The aim of this study was to investigate the causal effects between atrial fibrillation (AF) and kidney function.

METHODS AND RESULTS

We performed a bidirectional summary-level Mendelian randomization (MR) analysis implementing the results from a large-scale genome-wide association study for estimated glomerular filtration rate (eGFR) by the CKDGen (N = 765 348) and AF (N = 588 190) to identify genetic instruments. The inverse variance weighted method was the main MR method used. For replication, an allele score-based MR was performed by individual-level data within a UK Biobank cohort of white British ancestry individuals (N = 337 138). A genetic predisposition to AF was significantly associated with decreased eGFR [for log-eGFR, beta -0.003 (standard error, 0.0005), P < 0.001] and increased risk of chronic kidney disease [beta 0.059 (0.0126), P < 0.001]. The significance remained in MR sensitivity analyses and the causal estimates were consistent when we limited the analysis to individuals of European ancestry. Genetically predicted eGFR did not show a significant association with the risk of AF [beta -0.366 (0.275), P = 0.183]. The results were similar in allele score-based MR, as allele score for AF was significantly associated with reduced eGFR [for continuous eGFR, beta -0.079 (0.021), P < 0.001], but allele score for eGFR did not show a significant association with risk of AF [beta -0.005 (0.008), P = 0.530].

CONCLUSIONS

Our study supports that AF is a causal risk factor for kidney function impairment. However, an effect of kidney function on AF was not identified in this study.

Clinical differentiation between acute renal infarction and acute ureteral stone in the emergency department: A single-center retrospective case-control study

BACKGROUND

Few studies have compared renal infarction (RI) and ureteral stone (US), so there is insufficient evidence for emergency clinicians (ECs) to quickly suspect RI during the first assessment. Therefore, we compared the initial clinical presentation and laboratory findings of these diseases in the emergency department (ED) to determine a factor that may indicate RI.

METHODS

This single-center retrospective case-control study included 42 patients with acute RI and 210 with US who visited the ED from 2014 to 2020. Medical record data from first ED arrival were investigated, and clinical presentations, blood and urine test results obtained in the ED were compared and analyzed using logistic regression analysis.

RESULTS

ECs never suspected the initial diagnosis of RI as RI. The most common initial diagnosis was US (40.5%). Among patients with US, 150 patients (71.4%) were suspected of having US (p < 0.001). Abdominal pain (61.9%) was the most common chief complaint in the RI group, and flank pain (73.8%) was the most common in the US group (p < 0.001). 27 factors showed significant differences between the groups. Among those, age ≥ 70 years (odds ratio [OR]: 311.2, 95% confidence interval [CI]: 2.0-47,833.1), history of A-fib (OR: 149872.8, 95% CI: 289.4-7.8E+07), fever ≥37.5 °C (OR: 297.3, 95% CI: 3.3-27,117.8), Cl^- ≤ 103 mEq/L (OR: 9.0, 95% CI: 1.0-80.1), albumin ≤4.3 g/dL (OR: 26.6, 95% CI: 2.1-330.3), LDH ≥500 IU/L (OR: 17.9, 95% CI: 1.8-182.5), and CRP ≥0.23 mg/dL (OR: 7.5, 95% CI: 1.1-52.3) showed significantly high ORs, whereas urine RBCs (OR: 0, 95% CI: 0-0.02) showed a low OR (p < 0.05). The regression model showed good calibration (chi-square: 6.531, p = 0.588) and good discrimination (area under the curve = 0.9913).

CONCLUSIONS

When differentiating acute RI from US in the ED, age ≥ 70 years, history of A-fib, fever ≥37.5 °C, LDH ≥500 IU/L, Cl^- ≤ 103 mEq/L, albumin ≤4.3 g/dL, CRP ≥0.23 mg/dL and negative urine RBC result suggest the possibility of RI.

Renal Outcome and New-Onset Renal and Extrarenal Dissections in Patients With Nontrauma Renal Artery Dissection Associated With Renal Infarction

[Figure: see text].

Acute renal infarction: long-term renal outcome and prognostic factors

INTRODUCTION

Acute renal infarction is a rare occurence, whose  prognosis and long-term outcomes remain poorly studied. This study evaluated whether clinical and radiological features at diagnosis can be associated with the long-term outcomes (blood pressure, kidney function and mortality).

METHODS

We retrospectively analyzed the demographic, clinical, biological and radiological data of patients with acute renal infarction hospitalized at Rennes University Hospital between 1997 and 2017 (n = 94).

RESULTS

Patients were followed-up for a median of 60 months. At time of diagnosis of acute renal infarction median age was 53 years, 45% of the patients had acute hypertension, and 31% had Acute Kidney Injury (AKI) requiring dialysis in seven patients. The median Lactate DeHydrogenase (LDH) level was 977 IU/mL. The median extent of kidney damage was 14%, with left renal involvement in 51% of patients. At 60 months of follow-up, 66% of patients had developed Chronic Kidney Disease (CKD) stage 3 or higher, and 55% had hypertension since diagnosis. Age, acute development of hypertension and AKI at diagnosis were associated with long-term CKD (stage 3 or higher) in multivariate analyses, but the extent of kidney damage was not. During the follow-up, 21% of patients died, and only age resulted as a predisposing factor. No tested factor was correlated with long-term hypertension.

DISCUSSION

Age, acute development of hypertension, and AKI were correlated with long term CKD, whereas no factor was correlated with long-term hypertension after acute renal infarction.

The Value of Lactate Dehydrogenase in Predicting Rhabdomyolysis-Induced Acute Renal Failure; a Narrative Review

Introduction

Determining the diagnostic value of available biomarkers in predicting rhabdomyolysis-induced acute kidney injury (AKI) is a priority. This study aimed to review the current evidence about the value of lactate dehydrogenase (LDH) in this regard.

Methods

In this narrative review, the papers in PubMed, Embase, and web of science were studied. The keywords prognosis, prognoses, prognostic, LDH, rhabdomyolysis, emergency patients, and acute kidney failure or AKI had been selected from MeSH medical dictionary. Related papers written in English and published from November 2007 to December 2020 were selected.

Results

Finally, 14 articles were accepted for analysis. Among the selected articles, four were randomized clinical trials, seven were cross-sectional, and three were case-control studies. The results of the present review showed that abuse of illegal drugs is the most common cause of rhabdomyolysis. AKI is the most serious complication of rhabdomyolysis reported in the studies. These studies have shown a three-fold increase in AKI following drug-induced rhabdomyolysis. The review of the included articles shows that high LDH can predicts AKI, especially in critical and emergency situations such as rhabdomyolysis where there is a risk of death if diagnosed late. These studies show that LDH increases in the presence of renal failure and tissue damage.

Conclusion

Serum LDH is an appropriate and cost-effective prognostic indicator that can be used for risk classification of patients at risk for rhabdomyolysis-induced AKI.

Use of point-of-care ultrasound to diagnose an alternate cause of flank pain in a patient with presumed renal colic

This is a case of a 34-year-old male patient who presented to the emergency department (ED) with severe left flank pain. Due to the patient's cardiac history, elevated troponin, lactic acidosis, and lack of renal calculi on a noncontrast CT, focused cardiac ultrasound was performed, which showed left ventricle thrombus. The patient was later found to have bi-interventricular thrombi causing both pulmonary embolism and renal infarction. This is an uncommon diagnosis in the ED, where point-of-care ultrasound helped in diagnosing and guiding the management and disposition of this case.

Bilateral renal infarction in a patient with severe COVID-19 infection

Thromboembolic events are frequent in patients with COVID-19 infection, and no cases of bilateral renal infarctions have been reported. We present the case of a 41-year-old female patient with diabetes mellitus and obesity who attended the emergency department for low back pain, respiratory failure associated with COVID-19 pneumonia, diabetic ketoacidosis, and shock. The patient had acute kidney injury and required hemodialysis. Contrast abdominal tomography showed bilateral renal infarction and anticoagulation was started. Kidney infarction cases require high diagnostic suspicion and possibility of starting anticoagulation.

Case Report: Acute Renal Infarction in a Child With Coarctation of Aorta

Renal arterial infarction can present with hematuria, proteinuria, and hypertension, features often linked to glomerular disease. An aortic aneurysm is an extraordinarily rare complication of coarctation of the aorta. Acute renal infarction caused by emboli from the aortic aneurysm is a possible complication that has not been reported. We herein report a 10-year-old boy who presented with hematuria, proteinuria, hypertension, and skin rashes on both lower extremities mimicking acute glomerulonephritis but actually resulting from acute renal infarction caused by a coarcted aneurysm-associated thrombus. He was successfully treated with surgical excision of the coarcted aorta and aneurysm followed by subcutaneous low molecular weight heparin without recurrence.

Acute allograft dysfunction mimicking thrombotic microangiopathy in kidney transplant recipient with renal infarction: case report and review of literatures

Acute allograft dysfunction is rarely observed in kidney transplantation (KT). We report an unusual case of acute allograft dysfunction mimicking thrombotic microangiopathy (TMA) in recipient with renal infarction. A 65-year-old man underwent KT from his 39-year-old son. Pre-transplant donor evaluation was normal except for the branches of the upper and lower pole renal arteries originating from the aorta in renal computed topographic angiography, respectively. The immediate post-transplant clinical course was uneventful, but serum creatinine (SCr) increased from 2.2 to 4.5 mg/dL, anemia and thrombocytopenia were shown, and serum lactate dehydrogenase increased to 919 U/L on the third day after transplantation. We suspected TMA, because of no evidence of acute bleeding. The laboratory parameters associated with TMA were within normal ranges. Renal magnetic resonance angiography revealed a focal wedge-shaped perfusion defect in the upper pole of the graft and renal Doppler ultrasonography showed decreased perfusion of the lower pole of the graft. Graft function improved with conservative therapy. The patient was discharged with SCr of 1.21 mg/dL. Graft function has been stable after discharge. Acute allograft infarction should be considered in the differential diagnosis of acute allograft dysfunction mimicking TMA in recipients with grafts supplied by multiple renal arteries.

Renal artery dissection as an overuse Injury

The diagnosis of renal infarction is often convoluted due to its non-specific presentation. It can mimic disease processes as disparate as pyelonephritis, diverticulitis, or nephrolithiasis. This case is further complicated by the presence of a pelvic kidney with triplicate arterial input. It is difficult to estimate the incidence of pelvic kidneys as the numerous sources vary wildly in their estimations; however, the paucity information, in and of itself, speaks to the rarity of the condition. In this case, a 58-year-old male presents to the emergency department after experiencing sharp, sudden, and severe groin pain while swinging a golf club. The patient was noted to have an abnormally high systolic blood pressure in the 170s and hematuria, but all other initial labs and assessments were unremarkable. An initial computed tomography scan with intravenous contrast of the abdomen and pelvis showed partial necrosis of a pelvic kidney. Follow-up computed tomography angiography revealed that a dissection in one of the arteries supplying the kidney created an infarction and resultant necrosis. Vessel size, location and time between injury and diagnosis made endovascular intervention impractical. The patient was started on aspirin and Plavix, observed for 3 days and sent home.

Acute Renal Failure after Abdominal Trauma: Renal Artery Spasm Hypothesis in Ischemic Infarction in a 12-Year-Old Girl

Posttraumatic renal failure is often due to postischemic renal infarction, caused by identified vascular lesions. In our patient, a 12-year-old girl with acute anuric renal failure requiring hemodialysis after severe abdominal trauma, no vascular lesion or thrombosis was identified. Nevertheless, CT-scan and renal biopsy showed typical lesions of diffuse bilateral renal ischemic necrosis. The main hypothesis is a severe bilateral arterial vasospasm after a blunt abdominal trauma. The patient recovered only partially with persisting chronic renal failure.

Acute renal and splenic infarctions: a review

BACKGROUND

Renal and splenic infarctions are close entities, with few data concerning their clinical, biological and radiological features.

AIM

The aim of this study was to compare the clinical presentations, etiologies and outcomes of acute renal infarctions (RI) and splenic infarctions (SI).

DESIGN

A retrospective multicentric cohort study included patients of the 6 university hospitals in Lyon with RI, SI, or associated RI-SI infarctions was conducted.

METHODS

All consecutive cases diagnosed by CT imaging, between January 2013 and October 2016, were included. The exclusion criteria were causes of infarction that did not require additional investigations.

RESULTS

A total of 161 patients were selected for analysis: 34 patients with RI, 104 patients with SI and 23 patients with both RI-SI. Mean ± SD age of patients was 63.2 ± 16.6 years; 59.6% were male. Only 5/161 (3.1%) were healthy prior to the event. The main symptoms were diffuse abdominal pain (26.4%), followed by nausea/vomiting (18.3%) and fever (16.4%).The causes of RI or SI varied significantly within the three groups. Hypercoagulable state was associated with SI, and embolic disease and arterial injury were associated with RI. Extensive (i.e.>2/3 of organ volume) (OR 6.22, 95%CI 2.0119.22) and bilateral infarctions (OR 15.05, 95%CI 1.79-126.78) were significantly associated with hemodynamic shocks. The survival at 1 month follow-up did not significantly differ between the three groups.

CONCLUSION

Acute RI and SI are heterogenous entities in regards to their clinical presentation, etiology, associated venous or arterial thrombosis, but prognoses were not different at short term follow-up.

Idiopathic versus Provoked Renal Infarction: Characteristics and Long-Term Follow-Up of a Cohort of Patients in a Tertiary Hospital

BACKGROUND

There is limited evidence on the etiology and outcomes of renal infarction. A provoking factor is identified only in one- to two-thirds of patients.

METHODS

This is a retrospective observational study. The clinical characteristics and outcomes of patients with acute renal infarction were studied; the sample was divided into two groups according to the presence of at least one provoking factor at the time of diagnosis (atrial fibrillation, flutter, major thrombophilia, or renal artery malformations).

RESULTS

The study comprised 59 patients with a mean age of 63 (±16.7) years and a follow-up period of 3.1 (±2.8) years. An identifiable provoking factor was found for 59.3% of the renal infarctions at the time of diagnosis, and atrial fibrillation was the most frequent one (in 49.2% of all patients). Renal impairment was found in 49.2% of the patients at diagnosis and in 50.8% of the patients 6 months after the event (p = 0.525). When compared with the idiopathic group, the patients with provoked infarction were older (69.8 vs. 57.9 years, p = 0.014) and had a higher rate of recurrence of arterial thrombosis during follow-up (18.8 vs. 0%, p = 0.028), but there were no differences in the rest of the baseline characteristics or in mortality rates. Six patients (10.2%) in the idiopathic group were diagnosed with atrial fibrillation during follow-up.

CONCLUSIONS

Atrial fibrillation, both at diagnosis and at follow-up, is the most common identifiable cause of renal infarction; however, a significant number of patients are idiopathic, and these are younger, but they have a similar burden of cardiovascular disease and a lower risk of arterial recurrence.

NSAID associated bilateral renal infarctions: a case report

Renal infarctions (RIs) are caused by interruptions in the renal arterial blood flow. RIs are generally considered to be rare, however we present the case of a 37 year old woman whose renal infarction was likely due to the vasoconstrictive effects of non-steroidal anti-inflammatory drugs. Although high-dose non-steroidal anti-inflammatory drugs (NSAIDs) are known to cause a decrease in renal perfusion, they have not been accepted as causative agents in renal infarction. Theoretically, patients in prostaglandin dependent states should be more vulnerable to renovascular vasoconstriction and resulting hypoperfusion in the presence of NSAIDs. Given the high prevalence of NSAID use, we suspect that this mechanism of renal injury may be more prevalent than previously thought.

Bilateral Renal Infarction Secondary to Hypertrophic Cardiomyopathy

Bilateral renal infarction is a rare phenomenon which can be difficult to diagnose because the symptoms may often mimic renal calculi, infection, muscle inflammation, genital diseases, myocardial infarction, or ischemia. We present the case of a 55-year-old male patient who presented with non-radiating, left-sided flank pain associated with nausea and vomiting. A computed tomography (CT) scan of the abdomen and pelvis with contrast demonstrated bilateral renal infarction. A thorough workup was initiated, and the thrombus formation due to left atrial enlargement from hypertrophic obstructive cardiomyopathy was considered as the cause of the bilateral renal infarction in this patient. The patient's renal function improved with treatment, and she was discharged on an anticoagulant, considering her left atrial enlargement and renal infarction.

Renal and Splenic Infarction in a Patient with Familial Hypercholesterolemia and Previous Cerebral Infarction

Patient: Male, 47

Final Diagnosis: Acute renal and splenic infarction

Symptoms: Flank pain • low-grade fever

Medication: —

Clinical Procedure: CT scan

Specialty: Nephrology

Clinical outcomes associated with anti-coagulant therapy in patients with renal infarction

BACKGROUND

Patients with renal infarction are vulnerable to thromboembolic complications with poor outcomes. There is limited report concerning the effect of anti-coagulant therapy in this population.

AIM

To assess the impact of anti-coagulant therapy on outcomes in patients with renal infarction.

DESIGN

A retrospective cohort study of 101 renal infarction patients was conducted.

METHODS

The association between anti-coagulant therapy, all-cause mortality, thromboembolic complications and renal outcome was evaluated. Demographic data and comorbidities were collected for analysis. Anti-coagulant therapy was treated as a time-dependent variable. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multi-variate Cox proportional hazards models.

RESULTS

Fifty-seven (56.4%) patients with renal infarction received anti-coagulant therapy during the study period. The all-cause mortality rate was 7.56 per 100 patient-years. Age (HR 1.05, 95% CI 1.02-1.08) was a risk factor for all-cause mortality and anti-coagulant therapy was associated with a 92% improved survival (HR 0.08, 95% CI 0.02-0.34). Twelve (11.9%) thromboembolic events occurred following renal infarction. Current smoking (HR 10.37, 95% CI 1.60-67.43) had an adverse effect and anti-coagulant therapy (HR 0.14, 95% CI 0.03-0.73) had a significant protective impact on thromboembolic complications. There was no significant association between anti-coagulant therapy and long-term renal outcome in renal infarction patients including the monthly change in the estimated glomerular filtration rate (eGFR), the incidence of eGFR reduction of more than 50% and end-stage renal disease.

CONCLUSION

Anti-coagulant therapy in patients with renal infarction was associated with better survival and reduced thromboembolic complications.

Arterial thrombosis in unusual sites: A practical review

While cardiovascular disease is common, occasionally hematologists and other practitioners will encounter patients with arterial thrombosis/infarction in unusual sites, without clear cause or obvious diagnostic and treatment paradigms. Contrary to the more commonly encountered cerebrovascular accident and cardiovascular disorders, the various infarctions outlined in this review have unique presentations, pathophysiology, workup, and treatments that all hematologists should be aware of. This review outlines the current literature on arterial thrombosis, with consideration given to anatomic sources and hypercoagulable associations, while focusing on the epidemiology, pathophysiology, provoking factors, and current recommended treatments for intracardiac thrombus, primary aortic mural thrombus, visceral infarctions, and cryptogenic limb ischemia to provide a useful and practical review for the practitioner.

Renal infarction in vascular Ehlers-Danlos syndrome masquerading as pyelonephritis

Symptoms associated with numerous diseases can be indistinguishable from those of the urinary system disorders because receptors of many visceral organs as well as the body wall transmit sensation through pain fibers shared with the kidneys. Disregarding important family background of genetic disorder can be detrimental for some patients.

Acute renal artery embolisation: role of local catheter-based intra-arterial thrombolysis

A 45-year-old man without previous comorbidity presented to us with acute onset right-sided flank pain for last 14 hours. His general physical and systemic examination was unremarkable, and there were no clinical signs of peritonitis. The ultrasonography did not reveal any evidence of nephrolithiasis or hydronephrosis. His contrast-enhanced CT scan revealed hypoattenuated areas of right kidney and evidence of right renal artery thrombosis. He was immediately shifted to cardiac catheterisation lab, and his renal angiography showed thrombotic occlusion of right renal artery. The bolus dose of streptokinase (250 000 IU) was given locally in renal artery by right judkins catheter followed by systemic infusion of streptokinase (100 000 IU/hour) for 24 hours. After that he was started on low molecular weight heparin. Repeat renal angiography done after 5 days showed completely normal right renal artery. His cardiac and thrombophilia work up was negative, and he was discharged on antiplatelets, oral anticoagulants and statins.

Unilateral Acute Renal Artery Embolism: An Index Case of Successful Mechanical Aspiration Thrombectomy With Use of Penumbra Indigo Aspiration System and a Review of the Literature

Acute renal artery embolism (RAE) is a rare condition associated with significant morbidity and mortality. The treatment strategy for RAE includes anticoagulation with or without thrombolysis or surgical or endovascular embolectomy. We describe here a case presentation of acute RAE secondary to atrial fibrillation treated successfully with Penumbra Indigo Aspiration System, a novel device in peripheral endovascular interventions. Our patient had ongoing symptoms and acute renal failure on presentation with contraindication to thrombolysis given hypertensive emergency. A 6F Penumbra Aspiration catheter was used to aspirate large amounts of thrombus from segmental renal arteries with restoration of flow. Patient's symptoms and renal function returned to baseline after intervention. Penumbra system is used routinely in cerebral endovascular intervention, yet here we describe its potential use in peripheral vascular interventions in addition to a literature review of all available evidence for the different treatment modalities of acute RAE.

Renal Artery Thrombosis with Renal Infarction: A Rare Cause of Acute Abdomen

Renal artery thrombosis with renal infarction is a rare entity. Due to the nonspecific clinical presentation, the diagnosis is usually delayed. We describe such a case in a middle-aged man with membranous nephropathy who was in remission and presented with severe abdominal pain. He was managed with selective intra-arterial thrombolysis with a good outcome.

Spontaneous Renal Artery Dissection as a Cause of Acute Renal Infarction: Clinical and MDCT Findings

The purpose of this study was to assess the incidence of spontaneous renal artery dissection (SRAD) as a cause of acute renal infarction, and to evaluate the clinical and multidetector computed tomography (MDCT) findings of SRAD. From November 2011 to January 2014, 35 patients who were diagnosed with acute renal infarction by MDCT were included. We analyzed the 35 MDCT data sets and medical records retrospectively, and compared clinical and imaging features of SRAD with an embolism, using Fisher's exact test and the Mann-Whitney test. The most common cause of acute renal infarction was an embolism, and SRAD was the second most common cause. SRAD patients had new-onset hypertension more frequently than embolic patients. Embolic patients were found to have increased C-reactive protein (CRP) more often than SRAD patients. Laboratory results, including tests for lactate dehydrogenase (LDH) and blood urea nitrogen (BUN), and the BUN/creatinine ratio (BCR) were significantly higher in embolic patients than SRAD patients. Bilateral renal involvement was detected in embolic patients more often than in SRAD patients. MDCT images of SRAD patients showed the stenosis of the true lumen, due to compression by a thrombosed false lumen. None of SRAD patients progressed to an estimated glomerular filtration rate < 60 mL/min/1.73 m² or to end-stage renal disease during the follow-up period. SRAD is not a rare cause of acute renal infarction, and it has a benign clinical course. It should be considered in a differential diagnosis of acute renal infarction, particularly in patients with new-onset hypertension, unilateral renal involvement, and normal ranges of CRP, LDH, BUN, and BCR.

Idiopathic Renal Infarction Mimicking Appendicitis

Renal infarction is a rare cause of referral to the emergency department, with very low estimated incidence (0.004%–0.007%). Usually, it manifests in patients aged 60–70 with risk factors for thromboembolism, mostly related to heart disease, atrial fibrillation in particular. We report a case of idiopathic segmental renal infarction in a 38-year-old patient, presenting with acute abdominal pain with no previous known history or risk factors for thromboembolic diseases. Because of its aspecific clinical presentation, this condition can mimic more frequent pathologies including pyelonephritis, nephrolithiasis, or as in our case appendicitis. Here we highlight the extremely ambiguous presentation of renal infarct and the importance for clinicians to be aware of this condition, particularly in patients without clear risk factors, as it usually has a good prognosis after appropriate anticoagulant therapy.

Aspiration Thrombectomy of Acute Atrial Fibrillation-related Renal Artery Thromboembolism in a Patient with Horseshoe Kidney

BACKGROUND

Acute arterial thromboembolism to the renal arteries can be treated promptly by local thrombolysis, conventional surgical thrombectomy, or anticoagulation.

METHODS

We report a patient who presented with acute loin pain as a result of atrial fibrillation-related thromboembolism to the right renal artery supplying his horseshoe kidney. He was already on warfarin treatment with international normalized ratio of 1.7 and had acute bleeding from malignant peptic ulcer disease, so thrombolysis was contraindicated.

RESULTS

He underwent timely endovascular revascularization with aspiration thrombectomy, with good clinical and radiological consequence. He subsequently underwent curative partial gastrectomy and made a steady recovery.

CONCLUSION

Early endovascular target-directed therapy such as intra-arterial thrombolysis and mechanical aspiration in combination with intravenous heparin therapy will result in renal salvage.

[Bilateral renal infarction after discontinuation of anticoagulant therapy]

Acute renal infarction is an uncommon and often under diagnosed condition mostly because of misleading symptoms. Accurate data regarding clinical presentation, laboratory tests, diagnostic and treatment are lacking. Detection is often delayed or missed because of non-specific clinical presentation. The mechanisms of acute renal infarction are various, mainly embolic or thrombotic. Abdominal CT scan remains the most valuable exam to confirm the diagnosis. Therapeutic guidelines for the treatment of renal embolism have not been well established. The standard treatment strategy includes anticoagulation with or without thrombolysis. Despite the uncertainty regarding management, the renal outcome remains favorable. Some patients do develop some degree of renal insufficiency during the acute episode. We report here the case of a 73-year-old woman with bilateral acute renal infarction after discontinuation of anticoagulant therapy.

[Cohort of renal infarction during 2years at Grenoble teaching hospital]

BACKGROUND

Renal infarctions are rare events, clinical symptoms are various and diagnosis may be difficult, leading to diagnosis delay with kidney dysfunction risk.

METHODS

During 24 months (March 2013-February 2015), all patients admitted in nephrology, cardiology, or internal medicine for renal infarction were recorded. Cardiovascular risk, clinic-biologic and radiologic data were recorded. A prospective follow-up at 6 months was offered for each patient.

RESULTS

Eleven patients were admitted from emergency unit and 1 from general practitioner. Clinic symptoms are various: abdominal pain, headache, hypertension, and stroke. Diagnosis was not initially evocated, and was given by CT scan with 3 days median delay. Etiologies were composed of 5 dissections, 4 embolisms (atrial fibrillation), 1 cannabinoid arteritis, 1 thrombosis on atheroma, 1 thrombosis on postradiotherapy stenosis. Initial treatment was anticoagulation alone for 7 patients, with antiplatelet agent for 1 patient, anticoagulation followed by antiplatelet agent for 2 patients, and antiplatelet agent alone for 2 patients. We observed LDH elevation (4 cases on 5 available data) at admission; inflammatory syndrome, hypokalemia, and hypertension at 48-72h of symptoms. At 6months follow-up, one patient had altered glomerular filtration rate, and one patient had recidivism.

CONCLUSION

Delay of diagnosis is a real problem for renal infarction, and need to be evocated every flank pain. LDH elevation may help clinician to suggest renal infarction and lead to CT scan. Association of delayed inflammatory syndrome, hypertension and hypokalemia after flank pain strongly suggest renal infarction.

Asynchronous Bilateral Renal Infarction and Thrombophilia With Associated Gene Mutations in a 43-Year-Old Man: A Case Report

Renal infarction (RI) is frequently misdiagnosed or diagnosed late because of its rarity and nonspecific clinical presentation, which may result in irreversible damage to the renal parenchyma or increase the risk of other embolic events affecting additional organs. Multiple causal mechanisms and cases of idiopathic RI have been reported, but the causal factors are not clear in most cases.Here, we report the case of a patient with heterochronic bilateral RI caused by thrombophilia. Although he had several risk factors for hypercoagulation disorders, two gene mutations-MTHFR 677 C>T and PLG 1858G>A-were identified by genome sequencing of the entire exome. The findings suggest the possibility of a synergistic relationship between the two gene mutations.Thus, screening for gene mutations may provide additional clues for clarifying the cause of RI and thrombophilia.