Armanni-Ebstein lesions of the kidney: diagnostic of death in diabetic coma?

Risk of CKD among patients with DM taking diuretics or SGLT2i: a retrospective cohort study in Taiwan

BACKGROUND

This study aimed to evaluate the long-term risk of CKD and renal function declines using a combination of diuretics and SGLT2i.

METHODS

We selected the data of subjects who had at least two outpatient records or at least one inpatient record for DM treatment as the DM group from the National Health Insurance Research Database (NHIRD). Patients receiving versus not receiving SGLT2i were defined as the SGLT2i and non-SGLT2i cohorts, respectively. The patients in the two groups were matched 1:1 through propensity score matching based on age, sex, year of index date, and comorbidities.

RESULTS

The diuretics-only group had a higher risk of CKD (aHR, 2.46; 95% CI, 1.68-3.61) compared to the neither SGLT2i nor diuretics group, while the both SGLT2i and diuretics group and the SGLT2i only group had lower risks (aHR, 0.45, 95% CI, 0.32-0.63; aHR, 0.26, 95% CI, 0.17-0.40) than the diuretics-only group. The SGLT2i-only group had a lower risk (aHR, 0.58, 95% CI, 0.36-0.94) than the both SGLT2i and diuretics group.

CONCLUSION

This study indicates that diuretics could raise the risk of CKD in diabetic patients, but when used in combination with SGLT2i, they continue to offer protection against CKD.

Deaths From Alcoholic and Diabetic Ketoacidosis at Autopsy-A Comparison Study

Diabetes mellitus and alcoholism are common disorders that may result in sudden death. Ketoacidosis may occur in both conditions. Diagnosis is based on history, and post-mortem findings including biochemistry and toxicology. This study compares deaths from alcoholic and diabetic ketoacidosis from two centres with large autopsy workloads. In the study period 9332 deaths were autopsies with 151 deaths diagnosed as ketoacidosis (1.6%) with 82 (0.9 %) being diabetic ketoacidosis (DKA) and 48 (0.5%) alcoholic ketoacidosis (AKA) deaths. There were more male deaths in each group. The median age for DKA deaths was 51 years (range 19-79). The median age for AKA deaths was 55 years (range was 34-78). The BMI range in DKA deaths was 12.5 to 40.4 kg/m2, with a median of 21.9. The comparative figures for AKA deaths was a range of 11.3 - 38.3 with a median of 20.2. Acetone concentrations were statistically higher in diabetic compared with alcoholic deaths, mean of 33.7 mg/100 mL in DKA cases versus mean of 16.9 mg/100 mL in AKA cases. Both DKA and AKA deaths are seen more commonly in males than female and are typically people with low BMIs in their 50s.

Basal Vacuolization in Renal Tubular Epithelial Cells at Autopsy and Their Relation to Ketoacidosis

Basal vacuolization of renal tubular epithelial cells is a useful postmortem marker for ketoacidosis. To investigate its incidence and relationship to the severity of ketoacidosis, 158 autopsy cases with elevated β-hydroxybutyrate (>1 mmol/L) over a 7-year-period were retrospectively reviewed. Sixty-eight cases (43%) exhibited basal vacuolizations (vitreous β-hydroxybutyrate: 1.16-29.35 mmol/L, mean 10.28 mmol/L), and 90 cases (57%) did not (vitreous β-hydroxybutyrate: 1.03-13.7 mmol/L, mean 2.84 mmol/L). Quantitative analysis revealed on average a fourfold elevation in β-hydroxybutyrate in cases with basal vacuolizations compared to those without; 10.3% of cases with β-hydroxybutyrate concentrations between 1.01 and 2.00 mmol/L had basal vacuolizations, and this incidence increased to 33.3% with concentrations between 4.01 and 6.00 mmol/L. A marked increase in incidence to >70% was observed with concentrations >6.00 mmol/L, and basal vacuoles were invariably present (100%) with concentrations >14.01 mmol/L. This study demonstrates that basal vacuolizations are a sensitive marker for significant ketoacidosis and reaffirms its use as an indicator for likely cases of fatal ketoacidosis at autopsy.

An Isolated Perfused Rat Kidney Model for the Evaluation of the Effect of Glucose on Renal Tubular Epithelial Morphology

An isolated perfused kidney model was used to evaluate the effect of hyperglycemia on renal tubular epithelial cell morphology. Ten Sprague-Dawley rat kidneys were perfused with Krebs-Henseleit buffer containing 70 mmol/L of glucose (five for 1 h and five for 2 h). Two control groups consisted of 10 kidneys perfused with Krebs-Henseleit buffer without hyperglycemia (five for 1 h and five for 2 h), and 10 nonperfused contralateral kidneys placed in the same environment for the same duration. The hyperglycemia group had significantly increased renal tubular vacuolization (p < 0.001) compared to both control groups at 1 and 2 h. The isolated perfused kidney model recapitulates the renal tubular vacuolization phenotype found in hyperglycemia and may be a potential tool for the investigation into causal factors in renal histology. The full pattern of the Armanni-Ebstein phenomenon was not, however, reproduced, suggesting that this change requires more time or involves more complex factors.

Sudden Death Related to Diabetes Mellitus: Current and Emerging Relevance to the Forensic Pathologist

While diabetes mellitus (DM) has historically accounted for substantial worldwide morbidity and mortality, new and evolving epidemiologic trends are forcing the scientific community to view it as a type of emerging disease. This review will summarize the pathophysiology of the disease, present an update of current national statistics and changing epidemiologic patterns, discuss how DM might specifically lead to acute deaths falling under the jurisdiction of the medical examiner/coroner, and suggest a medicolegal standard of practice to maximize their capture and reporting.

Liver Pathology in First Presentation Diabetic Ketoacidosis at Autopsy

Diabetes mellitus is an enormous health burden on developed and developing nations. Eight percent of people in the United States are stated to have diabetes mellitus and 79 million people have impaired glucose tolerance. Sudden death from diabetic ketoacidosis (DKA) is common and nonalcoholic fatty liver disease (NAFLD) is a frequent finding in patients with diabetes mellitus and impaired glucose tolerance. Diabetic ketoacidosis accounts for around 1% of autopsy cases in our units and 25% of these cases did not have a previous diagnosis of diabetes mellitus. We have analyzed for the presence of NAFLD in 16 patients dying on first presentation of DKA. Some degree of NAFLD was present in all cases, with all but one case having some degree of steatosis and some degree of fibrosis was present in 14 out of 16 cases, though none where cirrhotic. Inflammation was present in nine of 13 cases and glyogenated nuclei in five of 13 cases. NAFLD can be well established in patients dying of DKA who were not known to be diabetic before death. The pathology shares features with alcoholic liver disease. They should not be mistakenly diagnosed as dying of other causes of ketoacidosis based upon the liver pathology present.

PI3K/AKT/mTOR pathway plays a major pathogenetic role in glycogen accumulation and tumor development in renal distal tubules of rats and men

Activation of the PI3K/AKT/mTOR pathway is a crucial molecular event in human clear cell renal cell carcinoma (ccRCC), and is also upregulated in diabetic nephropathy. In diabetic rats metabolic changes affect the renal distal tubular epithelium and lead to glycogen-storing Armanni-Ebstein lesions (AEL), precursor lesions of RCC in the diabetes induced nephrocarcinogenesis model. These lesions resemble human sporadic clear cell tubules (CCT) and tumor cells of human ccRCC.

Human sporadic CCT were examined in a collection of 324 nephrectomy specimen, in terms of morphologic, metabolic and molecular alterations, and compared to preneoplastic CCT and RCC developed in the rat following streptozotocin-induced diabetes or N-Nitrosomorpholine administration. Diabetic and non-diabetic rats were subjected to the dual PI3K/mTOR inhibitor, NVP/BEZ235.

Human sporadic CCT could be detected in 17.3% of kidney specimens. Human and rat renal CCT display a strong induction of the PI3K/AKT/mTOR pathway and related metabolic alterations. Proteins involved in glycolysis and de novo lipogenesis were upregulated. In in vivo experiments, dual inhibition of PI3K and mTOR resulted in a reduction of proliferation of rat diabetes related CCT and increased autophagic activity.

The present data indicate that human sporadic CCT exhibit a pattern of morphologic and metabolic alterations similar to preneoplastic lesions in the rat model. Activation of the PI3K/AKT/mTOR pathway in glycogenotic tubuli is a remarkable molecular event and suggests a preneoplastic character of these lesions also in humans.

Renal tubular epithelial vacuoles-a marker for both hyperlipidemia and ketoacidosis at autopsy

Review of 15 cases of nephrotic syndrome found that eight had significant hyperlipidemia with serum cholesterol levels ranging between 10.59 and 18.60 mmol/L (mean 12.88) and serum triglyceride levels between 2.30 and 9.92 mmol/L (mean 4.58); all of these cases displayed basal lipid vacuolization. Seven of the 15 study cases had normal-mild hyperlipidemia with serum cholesterol levels ranging between 4.71 and 7.54 mmol/L (mean 6.02) and serum triglyceride levels between 0.65 and 4.1 mmol/L (mean 1.57). Six of the seven cases had basal lipid vacuoles (86%). Of these, five cases were hyperlipidemic and one case had borderline hyperlipidemia with a serum cholesterol level of 4.71 mmol/L. Although hyperlipidemia was associated with renal tubular epithelial vacuolization, the vacuoles appeared morphologically different to those found in ketoacidosis. This study has shown that while hyperlipidemia in isolation may result in basal lipid vacuolization within renal tubular epithelial cells, the phenotype differs from that observed in ketoacidosis.

Effect of PACAP treatment on kidney morphology and cytokine expression in rat diabetic nephropathy

Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide, exerting diverse effects. One of its frequently examined functions is cell protection, which is achieved mainly via inhibiting apoptotic, inflammatory and oxidative processes. All its three receptors (PAC1, VPAC1, VPAC2) are expressed in the kidney and PACAP has been shown to have protective effects against different renal pathologies. Diabetic nephropathy is the leading cause of end stage renal disease. The aim of the present study was to investigate the possible ameliorative effect of PACAP in streptozotocin-induced diabetic nephropathy and to evaluate its anti-inflammatory effect in this model. Diabetes was induced by a single intravenous injection of streptozotocin (65 mg/kg) in male Wistar rats. PACAP-treated animals were administered ip. 20 μg PACAP every second day, while untreated animals were given vehicle. Kidneys were removed after 8-weeks survival. Besides the complex histological analysis (glomerular PAS positive area/glomerulus area, tubular damage, arteriolar hyalinosis), expression of several cytokines was evaluated by cytokine array and Luminex assay. Histological analysis revealed severe diabetic changes in kidneys of control diabetic animals (glomerular PAS-positive area expansion, tubular damage, Armanni-Ebstein phenomenon). PACAP treatment significantly diminished the damage. Diabetic kidneys showed significant cytokine activation compared to their healthy controls. PACAP was effective in downregulation of several cytokines including CINC-1, TIMP-1, LIX, MIG, s-ICAM. To conclude, PACAP is effective in ameliorating diabetic nephropathy at least partly through its well-known anti-inflammatory effect. These results raise the opportunity for the use of PACAP as a possible therapeutic or preventive method in treating the complications of diabetes.

The role of the Armanni-Ebstein lesion, hepatic steatosis, biochemical analysis and second generation anti-psychotic drugs in fatal diabetic ketoacidosis

Diabetic ketoacidosis (DKA) is an acute severe complication of diabetes and characterized by a complex disordered metabolic state due to an absolute or relative insulin deficiency, leads to hyperglycaemia, ketoacidosis and ketonuria. DKA can cause sudden unexpected death and often yields minimal and/or subtle autopsy findings or a negative autopsy and the diagnosis mainly depends upon biochemical analysis of body fluids. This communication highlights the role of Armanni-Ebstein lesion, hepatic steatosis, biochemical analysis and second generation anti-psychotic drugs in 25 adult cases of fatal diabetic ketoacidosis. The study recognises and reconfirms that fatal DKA occurs in both type I and II diabetes. The macroscopic autopsy features observed in this study are non-specific and do not guide the pathologist towards the diagnosis of fatal DKA. Once other possibilities have been excluded, the Armanni-Ebstein lesion alone or the combination of hepatic steatosis and Armanni-Ebstein lesion in an otherwise negative autopsy of a sudden unexpected death should raise the suspicion of DKA as the cause of death and indicate biochemical analysis of body fluids. Our findings also remind forensic pathologists to search for fatal DKA in sudden unexpected death with a negative autopsy, where there is a history of second generation anti-psychotic treatment.

The Armanni-Ebstein Lesion and the Postmortem Diagnosis of Ketoacidosis

The diagnoses of ketoacidosis and disturbances of glucose metabolism are difficult at autopsy because of changes in glucose concentrations postmortem. The Armanni-Ebstein lesion is a histological change in the kidney that has been reported as a marker of diabetic ketoacidosis. This paper examines the specificity of the Armanni-Ebstein lesion and the diagnosis of alterations in glucose metabolism and ketoacidosis at autopsy. The Armanni-Ebstein lesion consists of subnuclear vacuolation of the proximal tubules. The vacuoles contain fat and can be demonstrated on fresh and formalin fixed tissue using standard fat stains. Recently it has been reported in other conditions associated with non-diabetic ketoacidosis. The lesion has the same appearance whatever the cause of the ketoacidosis. This review, with illustrative cases shows the Armanni-Ebstein lesion is a marker of ketoacidosis and not specific for diabetic ketoacidosis. It may be seen in cases of diabetic and alcoholic ketoacidosis and in starvation and hypothermia, in which ketoacidosis occurs. It has also been reported in isopropanol poisoning.

Ameliorative Effects of Ethanolic Leaf Extract ofAzadirachta indicaon Renal Histologic Alterations in Streptozotocin-Induced Diabetic Rats

We studied the effect of ethanolic leaf extract of Azadirachta indica (AIE) on the microanatomy of the kidney of streptozotocin-induced diabetic rats. Thirty male Wistar rats (161–190 g) were randomly assigned to one of five treatment groups of six animals each: control, diabetic, diabetic + AIE, diabetic + metformin, AIE only. Diabetes was induced with a single intraperitoneal dose of streptozotocin (70 mg/kg body weight). AIE and metformin were administered orally for 50 days (50 d) at 500 mg/kg bw/d and 350 mg/kg bw/d, respectively. Blood glucose was estimated by glucose oxidase method; plasma urea and creatinine were assayed; and paraffin sections of the kidney were stained by periodic acid-Schiff technique. Untreated diabetic rats exhibited marked hyperglycemia. Renal histopathology of these animals showed features of diabetic nephropathy, with nodular glomerulosclerosis and vacuolation of proximal tubule cells (Armanni-Ebstein phenomenon). These feature were absent in the diabetic rats treated with AIE. Besides, plasma urea and creatinine were not significantly different from the control in this group (p > 0.05), in contrast to the untreated diabetic rats, where significant increases in these markers (p < 0.05). These findings showed that the leaf extract of Azadirachta indica ameliorates hyperglycemia and diabetic nephropathy in rats.

Sudden adult death

In the investigation of sudden death in adults, channelopathies, such as long QT syndrome, have risen to the fore in the minds of forensic pathologists in recent years. Examples of these disorders are touched upon in this review as an absence of abnormal findings at postmortem examination is characteristic and the importance of considering the diagnosis lies in the heritable nature of these conditions. Typically, a diagnosis of a possible channelopathy is evoked as an explanation for a 'negative autopsy' in a case of apparent sudden natural death. However, the one potential adverse effect of this approach is that subtle causes of sudden death may be overlooked. The intention of this article is to review and discuss potential causes of sudden adult death (mostly natural) that should be considered before resorting to a diagnosis of possible channelopathy. Nonetheless, it becomes apparent that many of the potential causes of sudden death can have a genetic basis. Thus, it becomes an important consideration that there may be a genetic basis to sudden death that extends beyond the negative autopsy.

Accumulation of triglycerides in the proximal tubule of the kidney in diabetic coma

AIMS

The present study was initiated by a very recent histochemical observation of lipid accumulation in the renal cortex of a woman who died in a diabetic coma. Two older reports of lipid accumulation in the kidneys of patients who died, most likely in a state of non-regulated diabetes, supported this observation. We have examined whether lipid accumulation in the renal cortex is characteristic of diabetic coma and, if so, which type of lipid accumulates.

METHODS

Three groups were studied. Ten subjects who died in a diabetic coma, eight diabetics who died of known causes unrelated to diabetes, and seven normal control subjects without any diagnosed diabetes who died of known causes. All were subjected to histological examination for lipid accumulation in the renal cortex. Detailed analysis of cortex lipids was performed for two of the subjects who died in a diabetic coma and all diabetic controls as well as non-diabetic control subjects.

RESULTS

All subjects who died in a diabetic coma showed vacuolar lesions staining strongly for lipid in the proximal tubules. Neither normal controls nor non-coma diabetics showed these lesions. Compared with normal controls, renal cortex lipid was about tripled in the two analysed diabetic coma subjects due to 60-100-fold increases of triglycerides. The non-coma diabetics did not differ from the other controls with respect to triglycerides or other types of lipid, except that cholesteryl esters were elevated, though still a quantitatively minor component.

CONCLUSION

Our findings strongly indicate that vacuolar lesions in the proximal tubules are characteristic of diabetic coma and that they are caused by accumulated triglycerides. Therefore, histological examination of renal cortex using a lipid stain may be a useful forensic tool in establishing diabetic coma as the cause of death.

Lipids in the proximal tubules of the kidney in diabetic coma

Vacuolization of the renal tubular epithelial cells (the Armanni-Ebstein lesion) associated with diabetic hyperglycemia is usually regarded as an accumulation of glycogen. In a case of death of diabetic coma, the vacuoles were stained strongly for lipids. This observation may have both clinical and therapeutic consequences, and may increase our knowledge of the metabolism in diabetes.