Renal cortical necrosis - a rare manifestation of dengue fever: A case report

RATIONALE

Dengue fever is a widespread mosquito-borne viral disease, most prevalent in the tropical and subtropical areas of the world. There has been a significant rise in the incidence and number of outbreaks of dengue in recent years, which has made it a matter of global concern. It may be associated with a number of renal complications, ranging from hematuria, proteinuria, glomerulonephritis, and acute tubular necrosis. However, renal cortical necrosis (RCN) is a rare renal complication of this disease.

PATIENTS CONCERNS

We report the case of a young gentleman who presented with fever, vomiting, and anuria. On workup, he was found to be having complicated Dengue fever with RCN resulting in acute renal failure.

DIAGNOSIS

To the best of our knowledge, RCN is not a reported renal complication of dengue fever.

INTERVENTIONS AND OUTCOMES

Our report highlights the importance of early consideration of renal cortical necrosis in patients with dengue fever and persistent anuria.

LESSON

This would allow for better disease prognostication while enabling physicians to develop more effective treatment strategies.

Pathologic Correlation with Renal Dysfunction after Intravitreal Injections of Vascular Endothelial Growth Factor Antagonists

OBJECTIVE

Vascular endothelial growth factor (VEGF) antagonists have been used for treating metastatic neoplasms. It has also been known that one of its side effects is to cause proteinuria and renal failure in the setting of thrombotic microangiopathy (TMA). The underlying mechanism is likely due to the inhibition of VEGF production in podocytes, resulting in diffuse fusion of foot processes and impaired glomerular endothelial fenestrations, and leading to massive proteinuria and subsequent glomerular endothelium injury. Intravitreal injection of VEGF antagonists (IIVA) has been also used to treat macular degeneration and diabetic retinal neo-vascular proliferation. The majority of patients tolerate the treatment well. However, IIVA can lead to renal dysfunction including proteinuria and gradual renal failure as a rare side effect. The goal of this study was to report two cases related to the nephrotoxicity of IIVA and review the literature associated with this topic.

CASE REPORT

The first diabetic patient had elevated serum creatinine at 3.25 mg/dl and proteinuria/creatinine ratio at 6.1 after 48-month treatment of IIVA. The first renal biopsy revealed thrombotic microangiopathy that was correlated with his increased serum creatinine and nephrotic range of proteinuria. The second diabetic patient had increased serum creatinine up to 1.89 mg/dl but low proteinuria. The second biopsy showed acute tubular necrosis that was correlated with his elevated serum creatinine.

CONCLUSION

Intravitreal injection of VEGF antagonist can be associated with thrombotic microangiopathy and acute tubular necrosis, leading to renal dysfunction.

Patterns of renal involvement in a cohort of patients with inflammatory bowel disease in Egypt

BACKGROUND AND STUDY AIM

Renal complications are frequent extraintestinal manifestations in inflammatory bowel disease (IBD). We aimed in our study to describe the spectrum of renal affection in our IBD patients.

PATIENTS AND METHODS

This study is a retrospective analysis of renal biopsies done for IBD patients who developed renal diseases, at Cairo University Hospital, from June 2005 to Jan. 2016. Results : Among 896 IBD patients, 218 patients (24.3%) developed renal affection. The onset of renal disease mandated renal biopsy at 5.6 ± 7.4 years after IBD diagnosis. Nephrotic range proteinuria was the most common indication for a renal biopsy [81 (37.15%) patients]. Amyloidosis was the most common renal pathological diagnosis [56 patients (25.7%)] followed by immunoglobulin A (IgA) nephropathy [35 patients (16.1%)], focal segmental glome- rulosclerosis (FSGS) [32patients (14.7%)], crescentic glomerulonephritis (CGN) [32 patients (14.7%)], membranous nephropathy (MN) [18 patients (8.25%)], minimal change disease [17 patients (7.7%)], chronic interstitial nephritis (CIN) [10 patients (4.6%)], acute tubular necrosis (ATN) [8 patients (3.7%)], thrombotic microangiopathy (TMA) [6 patients (2.75%)], and acute interstitial nephritis (AIN)[4 patients (1.8%)]. Variable renal histopathology diagnoses did not correlate with age, duration of IBD diagnosis, or drugs used for IBD treatment. Crescentic GN was significantly correlating with ASCA, ANCA-p, and ANCA-c in serum.

CONCLUSION

Amyloidosis is a common renal pathological diagnosis in our patients, and is followed by IgA nephropathy, and FSGS.

Aminoaciduria Caused by Fanconi Syndrome in a Heifer

A case study of renal tubular dysfunction consistent with idiopathic Fanconi syndrome is reported in an 18-month-old Holstein heifer. The clinical, biochemical, and histopathological features are described. The heifer had clinical signs of growth retardation, wasting, and persistent diarrhea. Biochemical blood analysis identified hypokalemia, hyponatremia, and hypochloremia. Urinalysis identified glycosuria, proteinuria, and acidic pH. Histological examination of the kidney disclosed mild tubular necrosis with proteinaceous casts in the lumina of renal tubules. We performed LC-HRMS on urine to confirm Fanconi syndrome. Using this technique, we identified severe generalized aminoaciduria suggestive of idiopathic renal Fanconi syndrome in this heifer.

Comparison of Ultrasound Corticomedullary Strain with Doppler Parameters in Assessment of Renal Allograft Interstitial Fibrosis/Tubular Atrophy

To compare the capability of ultrasound strain and Doppler parameters in the assessment of renal allograft interstitial fibrosis/tubular atrophy (IF/TA), we prospectively measured ultrasound corticomedullary strain (strain) and intra-renal artery Doppler end-diastolic velocity (EDV), peak systolic velocity (PSV) and resistive index (RI) in 45 renal transplant recipients before their kidney biopsies. We used 2-D speckle tracking to estimate strain, the deformation ratio of renal cortex to medulla produced by external compression using the ultrasound transducer. We also measured Doppler EDV, PSV and RI at the renal allograft inter-lobar artery. Using the Banff scoring system for renal allograft IF/TA, 45 patients were divided into the following groups: group 1 with ≤5% (n = 12) cortical IF/TA; group 2 with 6%-25% (n = 12); group 3 with 26%-50% (n = 11); and group 4 with >50% (n = 10). We performed receiver operating characteristic curve analysis to test the accuracy of these ultrasound parameters and duration of transplantation in determining >26% cortical IF/TA. In our results, strain was statistically significant in all paired groups (all p < 0.005) and inversely correlated with the grade of cortical IF/TA (p < 0.001). However, the difference in PSV and EDV was significant only between high-grade (>26%, including 26%-50% and >50%) and low-grade (≤25%, including <5% and 6%-25%) cortical IF/TA (p < 0.001). RI did not significantly differ in any paired group (all p > 0.05). The areas under the receiver operating characteristic curve for strain, EDV, PSV, RI and duration of transplantation in determining >26% cortical IF/TA were 0.99, 0.94, 0.88, 0.52 and 0.92, respectively. Our results suggest that corticomedullary strain seems to be superior to Doppler parameters and duration of transplantation in assessment of renal allograft cortical IF/TA.

[Acute tubular necrosis in kidney transplantation]

BACKGROUND

The acute tubular necrosis (ATN) is common after kidney transplantation. Acute tubular necrosis (ATN) is multifactorial and represents one of the main causes of the delayed graft function. Its impact on graft and patients survival is documented.

AIMS

To study the prevalence of the ATN in kidney transplanted patients, the acute rejection rate and their impact on the graft and the patient survival.

METHODS

We retrospectively studied the frequency of ATN, its causes and its impact on patient and graft survival in 255 kidney transplanted patients between 1986-2006.

RESULTS

Thirty-nine patients had ATN (15.29%). They are 25 men and 14 women with mean age of 30.1 ± 12.6 years (8-61) followed for an average of 98 ± 61.76 months. The majority was treated by hemodialysis (79.48%) and half of them were transplanted from kidney of deceased donor. All patients received anti lymphocyte serum and the majority anticalcineurins (69.23%). The outcome was favorable in 26 patients (66.66%) with recovery of diuresis and normalization of renal function after 6 weeks on average. An acute rejection was diagnosed in 21 patients (53.48%). The mean creatinine at 1, 5 and 10 years was 135.3, 159.9 and 121.4 μmol / l. Eight patients had creatinine ² 130 μmol / l at 10 years. Ten patients died from infectious and cardiovascular causes. By comparing the 2 groups ATN + and ATN - we found a statistically significant correlation between ATN and cold ischemia (10 ± 10.9 vs 1.2 ± 4.7 hours, p <0.0001) and the interval between the start of dialysis and transplantation (42.18 ± 38.44 vs. 31.1 ± 25.2 months, p= 0.02). No statistical correlation was found between the ATN and gender, age of recipient and donor, warm ischemia, acute rejection, chronic rejection and graft and patient survival at 1, 5 and 10 years.

CONCLUSION

The ATN is more common among transplanted patients from deceased donors. It had good evolution in the majority of cases and it's correlated to cold ischemia and duration of dialysis. Finally, it has no impact on patients and graft survival.

Anuric acute renal failure after elective abortion

Elective abortion complicated by bilateral renal cortical necrosis (BRCN) is not common in a developed country. We reported a patient having anuric acute renal failure after elective abortion. Initial laboratory studies implied thrombotic thrombocytopenic purpura/Hemolytic uremic syndrome, but plasma exchange was not prescribed since magnetic resonance imaging study suggested BRCN soon after. The patient was treated as septic abortion and reached partial renal recovery after antibiotic treatment and short-term hemodialysis. Early diagnosis of BRCN is essential not only for prognosis prediction but also for treatment decision. We suggest that any anuric patient in suspicion of BRCN should receive MRI study as soon as possible.

Pulmonary and systemic toxicity following exposure to nickel nanoparticles

Nanoparticles are being used in ever increasing numbers in a range of industrial and medical products. Questions surrounding their potential to cause toxic effects in humans have been raised. Although animal experiments predict that nanoparticles are more toxic than their larger counterparts there are few descriptions in the literature of human exposure. A case described in 1994 has been re-examined from a pathology perspective. The subject, a 38-year-old previously healthy male, inhaled nanoparticles of nickel while spraying nickel onto bushes for turbine bearings using a metal arc process. He died 13 days after being exposed and the cause of death at autopsy was adult respiratory distress syndrome (ARDS). Nickel particles <25 nm in diameter were identified in lung macrophages using transmission electron microscopy. High levels of nickel were measured in his urine and his kidneys showed evidence of acute tubular necrosis.

Obstetrical associated renal, cortical necrosis: uncommon but not rare!

BACKGROUND

Renal cortical necrosis (RCN) carries high morbidity and mortality in South East Asia. The purpose of this study was to look specifically at the incidence of obstetrical related RCN in renal biopsies and to evaluate its precipitating factors. In addition, prognosis, impact of aetiology and outcomes on discharge were also considered.

METHODS

The study was conducted in the Department of Nephrology, Lady Reading Hospital Peshawar, Pakistan. Renal biopsies of 1,670 patients were analysed during the study period of 1998 to 2008. All the patients with obstetrical related RCN were included. Patient records, demographic data, urine output on admission and preceding history of ante-partum haemorrhage (APH), post-partum haemorrhage (PPH), septicaemia, operative interventions and retained product of conception (ROPC) was noted and need for dialysis was considered.

RESULTS

Out of 1670 kidney biopsies analysed, 48 turned out to be RCN. Among them 39 patients (81.3%) had diffuse cortical necrosis, 6 patients (12.5%) had patchy cortical necrosis with ATN while 3 patients (6.3%) had predominant ATN with partial patchy cortical necrosis. Out of 48 patients, 25 (52.1%) were oliguric, 18 (37.5%) were anuric while 5 (10.4%) had urine output > 800 ml 24 hr. Operative interventions were found in 29 patients while 19 patients had normal vaginal delivery (NVD). 16 (55.2%) patients with operative intervention had PPH. Thus the association proved to be significant (p = 0.037).

CONCLUSION

Overall incidence of RCN was 2.9%. Oliguria/anuria on admission and dialysis dependency are associated with RCN. PPH and history of operative intervention have significant association and are contributing factors to development of RCN.

Influence of Spironolactone Treatment on Gentamicin-Induced Nephrotoxicity in Rats

The effect of treatment of rats with gentamicin (80 mg/kg/day for 6 days), oral doses of spironolacatone (20 mg/kg/day for 6 days), and the combined treatment (spironolactone + gentamicin) on renal histology and reduced glutathione (GSH) concentration, and some serum constituents indicative of kidney function were studied. The serum concentrations of creatinine and urea were not significantly affected by spironolactone treatment, but were significantly elevated (P<0.05) by gentamicin administration. The antibiotic treatment also reduced GSH concentration and caused a moderate renal cortical necrosis. However, rats exposed to spironolactone + gentamicin revealed drastic increases in the serum urea and creatinine concentrations amounting to about 1.8 and 2.1 times those of rats treated with gentamicin alone, respectively. The histological examination of slides of the renal cortex of rats exposed to the combined drugs exhibited more extensive necrosis in the tubules when compared to those treated with gentamicin alone. The reduction in GSH induced by gentamicin was unaffected by the concomitant treatment of gentamicin and spironolactone. The concentration of gentamicin accumulated in the renal cortex was significantly larger (twofold) in rats treated concomitantly with spironolactone + gentamicin than in rats treated with gentamicin alone. The present results indicate that spironolactone aggravates gentamicin-induced nephrotoxicity in the rat.

Prognosis and pathological characteristics of five children with non-Shiga toxin-mediated hemolytic uremic syndrome

BACKGROUND

The three major signs of hemolytic uremic syndrome (HUS) are hemolytic anemia, thrombopenia and acute renal failure. HUS is classified into Shiga toxin-mediated HUS (Stx-HUS) and non-Shiga toxin-mediated HUS (nStx-HUS). The prognosis of nStx-HUS is reported to be less favorable than that of Stx-HUS. Although the association between the prognosis and pathological characteristics of HUS have been reported such that the prognosis was considered to be poor for thrombotic microangiopathy (TMA) with predominant arterial involvement (arterial TMA), good for TMA with predominant glomerular involvement (glomerular TMA) and dependent on the extent of necrosis in cases of renal cortical necrosis, it is not yet clear whether pathological findings are also related to the renal prognosis of nStx-HUS cases. Therefore the purpose of the present paper was to analyze renal biopsy findings and prognosis for five children with nStx-HUS.

METHODS

Clinical records of five cases of nStx-HUS among 74 cases of diagnosed HUS were reviewed, and information and data were summarized.

RESULTS

Histological examination of the kidney led to the diagnosis of arterial TMA in three cases, and glomerular TMA and severe renal cortical necrosis in one case each. Analysis of the relationship between renal histological findings and the prognosis found that three patients with arterial TMA and one patient with severe renal cortical necrosis later developed end-stage renal failure while one patient with glomerular TMA has continued to show normal renal function.

CONCLUSIONS

These findings indicate that pathological findings are closely related to the prognosis in cases of nStx-HUS.

Renal cortical deterioration in children with spinal dysraphism: analysis of risk factors

BACKGROUND/OBJECTIVE

Because hydronephrosis and reflux are reversible, we believe cortical loss represents true renal deterioration in children with spinal dysraphism. Our goal was to better define risk factors for cortical loss.

METHODS

After institutional review board approval, we reviewed the medical records of 272 children with spinal dysraphism. The following factors were evaluated: age, sex, renal and bladder imaging, urodynamic parameters, medications, catheterization program, continence, infections, and surgical history. Renal cortical loss was defined by scarring or a differential function greater than 15% using a nuclear scan. Univariate and multivariate logistic regression models were fitted to test the associations of specific variables with cortical loss.

RESULTS

Renal cortical loss was found in 41% of children with high-grade reflux vs. 2% of children without reflux. Univariate analysis showed only high-grade reflux and female sex to be independent risk factors. Controlling for age and sex, reflux and initiation of catheterization after 1 year of age are significant risk factors. High bladder pressure and hydronephrosis in the absence of reflux were not associated with cortical loss. Multivariate analysis showed that girls with reflux have a 55-fold increased risk of cortical loss.

CONCLUSION

By limiting the definition of renal deterioration to cortical loss, we identified relevant risk factors: reflux, female sex, and delayed initiation of clean intermittent catheterization. We have also discounted other suspected risk factors: hydronephrosis and elevated bladder pressure. Rather than continuing our focus on hydronephrosis and urodynamics, we believe more research and management debate should be afforded to females with reflux.

Microscopic polyangiitis associated with primary biliary cirrhosis: a causal or casual association?

The association between microscopic polyangiitis (MPA) and primary biliary cirrhosis (PBC) has seldom been reported. We describe a patient with PBC and MPA who presented with polyarthritis and pulmonary nodules followed by pauci-immune crescentic glomerulonephritis and liver dysfunction. Detection of p-ANCA, antimyeloperoxidase, and antimitochondrial antibodies along with liver and renal histopathology allowed a diagnosis of MPA and PBC. We also discuss 2 other cases that could be unrecognized associations of both diseases. Further reports are necessary to clarify if the coexistence between PBC and MPA is causal or casual.

Acute renal failure in pregnancy in a developing country: twenty years of experience

Acute renal failure (ARF) has become a rare complication of pregnancy in developed countries. The aim of this study was to describe changing trends in pregnancy-related acute renal failure (PR-ARF) in two successive periods; 1982-1991 and 1992-2002. From July 1982 to December 2002, 190 cases of PR-ARF were observed in Eastern India (11.6% of total number of ARF needing dialysis). Obstetrical complications were causative factors for ARF in 15% (65/426) and 10% (125/1201) of patients in the two periods, respectively. The incidence of PR-ARF fell from 15% in 1982-1991 to 10% in 1992-2002, with respect to the total number of acute renal failure cases. Post-abortal ARF showed a declining trend, 9% in the 1980s to 7% in the 2000s, of the total number of ARF cases. Preeclampsia-eclampsia was the cause of obstetrical ARF in 23% (1982-1991) and 14.4% (1992-2002) of cases in these two periods. The percentage of total ARF due to eclampsia declined from 3.5% during the period 1982-1991 to 1.4% in 1992-2002. Puerperal sepsis contributed to 0.8% of total ARF in recent years, compared to 2.4% in the earlier period. The incidence of cortical necrosis decreased significantly (p < 0.001) from 17% in 1982-1991 to 2.4% in the 2000s. The maternal mortality reduced to 6.4% in 1992-2002 from initial high mortality of 20% in the period of 1982-1991.

CONCLUSION

PR-ARF which remained high in the initial period has decreased in recent years. This is associated with a declining trend in

Renal Cortical Necrosis Related to Paraneoplastic Antiphospholipid Syndrome

Acute bilateral renal cortical necrosis is a very rare cause of acute renal failure. We report here for the first time a case related to antiphospholipid syndrome, paraneoplastic of a lung neoplasia. A 46-year-old male smoker without medical history was admitted for acute dyspnea and anuria. Biological examination showed acute renal failure associated with hyperkalemia, high serum lactate dehydrogenase level, and prolonged activated thrombin time (ratio 1.29). Chest radiograph showed a right laterotracheal round lesion. A percutaneous left renal biopsy showed cortical necrosis, and renal arteriography confirmed bilateral cortical necrosis. Blood examination showed antiphospholipid antibodies type anticardiolipin. Chest computed tomographic scan confirmed the presence of a lung tumor. Two years after tumor surgery, the patient was still anuric and on long-term hemodialysis therapy, but antiphospholipid antibody results were negative. This case describes the first association of antiphospholipid syndrome to epidermoid lung cancer, shown by cortical bilateral necrosis. It also emphasizes the utility of renal biopsy in case of an unusual acute renal failure.

Ocular lesions and experimental choline deficiency

Previous studies have shown ocular haemorrhages in choline-deficient rats. The aim of this paper is to study further the relationship between ocular and renal lesions and biochemical alterations in rats fed a choline-deficient diet. Fifty one weanling male Wistar rats, were divided into two groups. Thirty one of them were fed a choline-deficient diet and the rest was fed a choline-supplemented diet ad libitum. Animals from both groups were killed between the fifth and the eighth day. Urea, creatinine and homocysteine concentrations in blood were determined. Eyes were used for light microscopy study; high resolution light microscopy and the study of the retina as "rétine a plat". Kidneys were studied by light microscopy. Choline-supplemented rats did not show ocular or renal lesion. Choline-deficient rats that showed renal lesions, tubular or cortical necrosis, did not always have ocular changes. There were no ocular changes in the only choline-deficient rat without renal lesion. The ocular changes consisted mainly in haemorrhage in both cameras and ciliary and vitreous bodies. Correlations between ocular and renal lesion (r = 0.72, p < 0.0001, CI 95%: 0.48-0.86); ocular lesion and creatinine (r = 0.86, p < 0.0001, Cl 95%: 0.72-0.93) and ocular lesion and urea (r = 0.70, p < 0.0001, Cl 95%: 0.44-0.85) were positive. Choline-deficiency induces ocular haemorrhagic lesions after the development of renal necrosis. The ocular pathology could be due to the immaturity of the ocular vasculature at this age. The hyaloid, choroid and retinal system are involved.

Eine neue Methode zur standardisierten Diagnostik nach Nierentransplantation

Ultrasound (US) imaging is an important diagnostic tool following renal transplantation. Unfortunately, due to the heterogeneity of the recipients and their multimorbidity, imaging procedures in the early phase after kidney transplantation are difficult and of limited use. We performed a study to evaluate the use of a contrast enhancer for US examination as a standardized method in the follow-up of kidney transplant recipients.The study included 40 recipients: 32 were examined on the 5th to 7th day following transplantation and 8 patients at the time when clinically suspicious findings occurred (acute rejection, tumor, acute tubular necrosis). Following the intravenous application of the contrast medium, pictures were taken during the arterial and parenchymatous phase and compared with conventional B-mode and power Doppler pictures of the same visual plane. Three examiners assessed different parameters of the transplant organ (max. vascularized area, suspected hematomas, tumors, rejection, acute tubular necrosis). Findings were confirmed by histological results of a biopsy if rejection, tumor, or acute tubular necrosis were suspected. Application of ultrasound contrast medium significantly increased visualization of the vascularized kidney area. Also, US findings in the follow-up after acute rejection therapy corresponded with the clinical course; 19 hematomas could be detected with contrast medium compared to only 9 without. With contrast medium a perfusion deficit was detectable in three patients compared to one patient with power Doppler US. Also, US contrast medium helped to detect tumor vascularization in two patients in whom conventional sonography suspected no abnormality. Ultrasound contrast medium enhancement is a reproducible, reliable, and easy to apply method which is superior to conventional sonography in the follow-up after kidney transplantation. This method is also helpful to detect and control acute rejections and to better visualize hematomas, deficits of perfusion, and tumors.

Incidence of Renal Infarctions After Transrenal Stent Placement in an Animal Model

PURPOSE

To evaluate the incidence and appearance of renal infarctions after transrenal stent placement in an animal model.

METHODS

An aortic stent was placed via a femoral approach in 20 female Merino sheep. Ten animals had intentional coverage of one renal ostium with the bare struts, 1 sheep had both renal artery ostia covered, and the other 9 sheep had no stent impingement on the renal orifices. Animals were sacrificed after 3 to 12 months (mean 6) for gross pathological and histological evaluation. Infarction locations and patterns were evaluated and correlated to stent placement.

RESULTS

Of the 40 renal arteries, coverage was proven at autopsy in 12 cases; the remaining 28 arteries were free of any stent overlay. Overall, 14 (35%) renal infarctions were detected; 7 were found in the 12 arteries with a transrenal stent (58.3% incidence in covered renal arteries). By comparison, the other 7 infarctions were found in the 28 unaffected arteries (25% incidence in noncovered renal arteries; p = 0.04). All infarctions appeared to be well-defined punctate lesions.

CONCLUSIONS

A transrenal stent position in the abdominal aorta is related to increased renal infarctions in an animal model.

Type III cryoglobulinemia complicated by renal cortical necrosis

Renal involvement is rare in patients with type III cryoglobulinemia. We report a case of renal cortical necrosis in a patient with type III cryoglobulinemia. Renal function improved partially after treatment with plasma exchange, steroids, and cyclophosphamide. Renal magnetic resonance imaging was a valuable tool in the evaluation of the extent of renal cortical necrosis and improvement in renal vascularization after treatment.

Morphological changes induced in the pig kidney by extracorporeal shock wave lithotripsy: nephron injury

While shock wave lithotripsy (SWL) is known to cause significant damage to the kidney, little is known about the initial injury to cells along the nephron. In this study, one kidney in each of six juvenile pigs (6-7 weeks old) was treated with 1,000 shock waves (at 24 kV) directed at a lower pole calyx with an unmodified HM-3 lithotripter. Three pigs were utilized as sham-controls. Kidneys were fixed by vascular perfusion immediately after SWL or sham-SWL. Three of the treated kidneys were used to quantitate lesion size. Cortical and medullary samples for light (LM) and transmission electron microscopy (TEM) were taken from the focal zone for the shock waves (F2), the contralateral kidney, and the kidneys of sham-SWL pigs. Because preservation of the tissue occurred within minutes of SWL, the initial injury caused by the shock waves could be separated from secondary changes. No tissue damage was observed in contralateral sham-SWL kidneys, but treated kidneys showed signs of injury, with a lesion of 0.2% +/- 0.1% of renal volume. Intraparenchymal hemorrhage and injury to tubules was found at F2 in both the cortex and medulla of SWL-treated kidneys. Tubular injury was always associated with intraparenchymal bleeding, and the range of tissue injury included total destruction of tubules, focal cellular fragmentation, necrosis, cell vacuolization, and membrane blebbing. The initial injury caused by SWL was cellular fragmentation and necrosis. Cellular vacuolization, membrane blebbing, and disorganization of apical brush borders appear to be secondary changes related to hypoxia.

Renal artery dissection after blunt abdominal trauma: a rare cause of acute cortical necrosis

Renal artery injury is an uncommon complication of blunt abdominal trauma. We present a case of a 19-year-old man who developed acute cortical necrosis in a congenital single kidney after a motorcycle accident. On initial presentation, he had signs of splenic injury and required immediate laparotomy and splenectomy. His renal function deteriorated, and he became dialysis dependent. Computed tomography followed by percutaneous angiography showed a dissection of a single renal artery causing the formation of a large pseudoaneurysm. A second angiogram showed an increase in the size of the pseudoaneurysm. We performed a laparotomy and attempted in situ vein graft repair of the renal artery. A wedge biopsy specimen taken at laparotomy revealed acute cortical necrosis, and plain radiographs showed cortical calcification. Renal artery dissection and pseudoaneurysm formation are rare events after blunt trauma. Iatrogenic damage is the most common cause of pseudoaneurysm. Traumatic pseudoaneurysms have a poor prognosis without prompt surgical intervention. Renal arterial damage may occur after blunt trauma, and early imaging and intervention are essential to salvage renal function.

Acute bilateral renal cortical necrosis as a cause of postoperative renal failure

Acute renal failure after a major intra-abdominal operation is, unfortunately, not an infrequent occurrence. Acute tubular necrosis, the most common cause of postoperative renal failure, usually follows a predictable clinical course, with most patients recovering full renal function. We describe a patient who developed acute renal failure after orthotopic liver transplantation. Subsequent workup revealed the patient to have acute bilateral renal cortical necrosis. Bilateral renal cortical necrosis is an extremely rare cause of renal failure and an even rarer cause of postoperative renal failure. We discuss the diagnosis and management of this uncommon disorder and review the salient literature. Of the approximately 15 known reported cases involving native kidneys after a major nonobstetric abdominal operation in the world literature, we believe this is the first to be related to an orthotopic organ transplant.

Laparoscopic and computed tomography-guided percutaneous radiofrequency ablation of renal tissue: acute and chronic effects in an animal model

OBJECTIVES

To evaluate the laparoscopic and percutaneous delivery of impedance-based radiofrequency ablation (RFA) of the kidney by studying the acute and chronic clinical, radiographic, and histopathologic effects in the porcine model.

METHODS

Eight kidneys from 4 pigs underwent laparoscopic RFA. Six kidneys from 3 additional pigs received computed tomography (CT)-guided, percutaneous RFA. CT scans were performed immediately after RFA and before harvest at 2 hours, 24 hours, 3 weeks, and 13 weeks. The gross, radiographic, and histopathologic changes were recorded for each period.

RESULTS

Grossly, the RFA lesions were sharply demarcated, measuring 3 to 5 cm. Two major complications (14%) occurred (one urinoma, one psoas muscle injury) in 14 ablations. No deaths or significant blood loss occurred as a result of RFA. Radiographically, the immediate CT scanning demonstrated small perinephric hematomas and wedge-shaped defects. Delayed CT showed nonenhancing defects up to 5 cm. Color-flow and power Doppler were unable to distinguish significant tissue changes during RFA. The histopathologic evaluation revealed marked inflammation surrounding the necrotic regions in the early lesions; chronic lesions were characterized by dense fibrosis. The tissue temperatures ranged from 62 degrees to 118 degrees C in the area of ablation.

CONCLUSIONS

RFA is readily delivered laparoscopically or percutaneously with minimal morbidity. Impedance-based application of radiofrequency energy allows monitoring and control of ablation. Using a multi-antenna probe, areas of tissue up to 5 cm can be completely destroyed. The RFA lesion can be monitored as a nonenhancing cortical defect on CT.

Protective effect of myristic acid on renal necrosis occurring in rats fed a methyl-deficient diet

Weanling rats fed a methyl-deficient diet develop acute renal failure, the morphological features of which vary from focal tubular necrosis to widespread cortical necrosis. We and others have shown that coconut oil, rich in saturated fatty acids, has a renal protective effect in this experimental model. In the experiment we are reporting now, we studied which fatty acid is involved in the protection afforded by coconut oil by feeding five groups of methyl-deficient rats a mixture of corn oil and hydrogenated vegetable oil, C6-C8-C10 fatty acids, C12 fatty acid, C14 fatty acid and C16-C18 fatty acids. Five groups of rats receiving the same diets supplemented with choline chloride were used as controls. The group of methyl-deficient rats fed C14 fatty acid (myristic acid) showed a greater percentage of surviving animals and lower renal damage than the other groups of methyl-deficient rats, indicating that the protective effect of coconut oil found in previous experiments is due to its high content of myristic acid.

CT scan as an important diagnostic tool in the initial phase of diffuse bilateral renal cortical necrosis

The serious clinical circumstances and coagulopathy generally accompanied by diffuse bilateral renal cortical necrosis (BRCN), especially during the early period, do not allow renal biopsy being well known as a gold standard diagnostic method for BRCN. Therefore, other noninvasive diagnostic modalities in the initial phase of BRCN have been tried, and, among them, contrast-enhanced computerized tomography (CT) was found to provide very characteristic representative findings, i.e., low attenuation of cortex sparing thin rim of subcapsular cortex and medulla, correlating well with histological findings of renal biopsy performed in the late somewhat stable clinical status or at autopsy. These specific CT findings were reported consistently with or without renal biopsy in several articles recently. Herein, we present a 38-year-old woman of massive automobile accident victim, developed protracted total anuria as well as shock with disseminated intrasvascular coagulation (DIC), and diagnosed as BRCN by the specific CT findings without renal biopsy in the second day of admission. Simultaneously, all the scattered cases of BRCN diagnosed by CT are reviewed and contrast to the findings of other diagnostic procedures performed for the same cases. The importance of contrast-enhanced CT as noninvasive diagnostic procedure during the initial phase of BRCN is stressed.

Protective effect of coconut oil on renal necrosis occurring in rats fed a methyl-deficient diet

Weanling rats fed a methyl-deficient diet develop renal necrosis with acute renal failure. The aim of this experiment was to explore further the role of coconut oil in this experimental model. Weanling Wistar male rats were fed methyl-deficient and their controls were fed methyl-supplemented diets. Coconut oil was fed at 14% and 20%, the latter concentration with and without 1% safflower oil (rich in linoleic acid); other groups received similar diets but instead of coconut oil, a mixture of hydrogenated vegetable oil and corn oil (rich in unsaturated fatty acids) was employed. Coconut oil fed at a 14% concentration did not evidence any protective outcome in relation to the renal lesions. Coconut oil at a 20% concentration showed a protective effect, mainly when the diet included safflower oil. The renal protective effect was evidenced by less or no mortality and increased survival time in the methyl-deficient rats receiving coconut oil, as well as by a reduced incidence (%) and severity of the renal lesions as evaluated by renal weight, and type (tubular and cortical necrosis or repair) and extent (grade) of the renal damage. The lack of a protective outcome when coconut oil was fed at 14%, along with the fact that in those rats receiving coconut oil at 20% the protection was greater when the diet was supplemented with 1% safflower oil, indicates that the protective effect should be attributed to the type of fatty acids coconut oil has and not to their shortage of essential fatty acids.

Acute renal cortical necrosis--a study of 113 patients

Over a 28-year period, 113 out of 2986 (3.8%) patients dialysed for acute renal failure at a referral center in North India were diagnosed to have acute renal cortical necrosis (ACN). Obstetric causes were responsible for ACN in 56.6% patients and nonobstetric causes in 43.4%. Within the obstetric group, ACN developed in association with complications of late pregnancy in 37.1% and following septic abortion in 19.5%. The various nonobstetric causes included viperine snake bite in 14.2%, hemolytic uremic syndrome in 11.5%, renal allograft rejection in 5.3%, acute gastroenteritis in 4.4%, acute pancreatitis in 3.5%, septicemia in 2.7%, and trauma and drug-induced IV hemolysis in 0.9% patients. Total anuria was the commonest presenting feature and was noted in 78.8% of patients. Renal histology showed diffuse cortical necrosis in 62.8% and patchy lesions in 37.2% patients. Computerized tomography (CT scan) of the kidneys revealed characteristic diagnostic findings in all the 5 patients in whom it was done. Dialytic support could be withdrawn as a result of improvement in renal function in 19 patients with patchy cortical necrosis. Dialysis-free survival of as long as 12 years has been recorded. The present study shows that, in contrast to the Western world, ACN continues to be a common cause of acute renal failure in developing countries. CT scan of the kidneys is helpful in establishing an early diagnosis.

Case report: sonographic detection of renal transplant cortical calcification

Cortical calcification in a transplanted kidney was detected by high resolution ultrasound, not visible on plain abdominal radiography. Early recognition of these sonographic appearances should lead to a more accurate diagnosis and institution of appropriate treatment in patients with post-operative transplant dysfunction.

MR imaging of acute renal cortical necrosis. A case report

MR imaging of a patient with acute renal cortical necrosis secondary to massive bleeding following an abortion is presented. The kidneys were enlarged with a high signal intensity observed in the renal cortex on both T1- and T2-weighted images. Follow-up MR imaging showed thinned renal cortex of low signal intensity on both pulse sequences representing renal cortical calcification which was confirmed on conventional radiography and CT.

Acute intrapartum twin-twin transfusion. A case report

A rare case of acute intrapartum twin-twin transfusion occurred. The well-recognized criteria of long-standing chronic twin-twin transfusion were absent. Although a cesarean section was performed for obstetric reasons, the hyperperfused twin, A, died intrapartum. Twin B, the hypoperfused twin, although liveborn, died neonatally of renal failure attributed to renal cortical necrosis as a sequel to hypotension.

The roles of glucocorticosteroid and of fibrinolytic activity in the development of bilateral renal cortical necrosis in cycloheximide-treated mice challenged with a submicrogram dose of endotoxin

Mice given cycloheximide and 0.2 microgram of endotoxin simultaneously developed ischaemic bilateral renal cortical necrosis as part of a fatal syndrome. Endotoxin given 2 h after cycloheximide, although fatal, failed to produce renal cortical necrosis. Investigation suggested that, following endotoxin challenge in cycloheximide-treated mice, the occurrence or non-occurrence of bilateral renal cortical necrosis was determined by the concentration of circulating glucocorticoids at the time of endotoxin challenge. Thus, below a certain, as yet undefined, glucocorticoid concentration, endotoxin does not cause renal cortical necrosis in cycloheximide-treated mice. Inhibition of the fibrinolytic system by epsilonaminocaproic acid (EACA) indicated that protection against renal cortical necrosis was directly mediated by increased fibrinolytic activity. Since this increased activity occurred during a period of profound cycloheximide-mediated inhibition of protein synthesis, it was postulated that pre-existing plasminogen activator was released from inhibition, and that this release could only occur when the glucocorticoid concentration fell below a certain critical value.

In vivo release of cisplatin from a needle-type copolymer formulation implanted in rat kidney

Cisplatin, cis-dichlorodiamine platinum (II), was incorporated in a needle-type copolymer formulation (0.8 mm diameter, 6 mm long) by radiation-induced polymerization. The copolymer used was copoly(diethylene glycol dimethacrylate/polyethylene glycol #600 dimethacrylate, 80/20 vol%). This copolymer, containing 6 mg of cisplatin, was implanted into the kidney of adult male Wistar rats (420 +/- 20 g). A total of 70 d was required for 100% release of cisplatin in vivo. The kidney tissue surrounding the formulation was strongly necrotized by the action of cisplatin. Two layers of necrosis could be distinguished: necrotic tissue surrounding the formulation and necrobiotic tissue surrounding the necrotic tissue. The amount of necrotic tissue changed markedly over time, but no change was apparent in the amount of necrobiotic tissue. The maximal amounts of necrotized tissue were observed 14 d after implantation: 3100 microns and 600 microns thick for the necrotic and necrobiotic tissues, respectively.