Septic Ketoacidosis-A Potentially Lethal Entity with Renal Tubular Epithelial Vacuolization

Autophagy ablation in skeletal muscles worsens sepsis-induced muscle wasting, impairs whole-body metabolism, and decreases survival

Septic patients frequently develop skeletal muscle wasting and weakness, resulting in severe clinical consequences and adverse outcomes. Sepsis triggers sustained induction of autophagy, a key cellular degradative pathway, in skeletal muscles. However, the impact of enhanced autophagy on sepsis-induced muscle dysfunction remains unclear. Using an inducible and muscle-specific Atg7 knockout mouse model (Atg7iSkM-KO), we investigated the functional importance of skeletal muscle autophagy in sepsis using the cecal ligation and puncture model. Atg7iSkM-KO mice exhibited a more severe phenotype in response to sepsis, marked by severe muscle wasting, hypoglycemia, higher ketone levels, and a decreased in survival as compared to mice with intact Atg7. Sepsis and Atg7 deletion resulted in the accumulation of mitochondrial dysfunction, although sepsis did not further worsen mitochondrial dysfunction in Atg7iSkM-KO mice. Overall, our study demonstrates that autophagy inactivation in skeletal muscles triggers significant worsening of sepsis-induced muscle and metabolic dysfunctions and negatively impacts survival.

Renal Tubular Epithelial Subnuclear Vacuolization in Hypothermia and Diabetic Ketoacidosis-A Retrospective Autopsy Study

ABSTRACT

Subnuclear vacuolization of the renal tubular epithelium refers to discrete lipid vacuoles displacing the nuclei toward the lumen. This phenomenon has been associated with conditions sharing fatal ketoacidosis as a common denominator. This retrospective study aimed to investigate renal tubular epithelial subnuclear vacuolization and other postmortem examination findings in fatal hypothermia and diabetic ketoacidosis (DKA) cases.Fourteen cases with hypothermia and 19 cases with DKA were included. More cases with DKA had focal or diffuse subnuclear vacuolization compared with hypothermia cases (89% vs 43%; P = 0.007). In 6 cases with DKA, formalin pigment was detected within subnuclear vacuoles, whereas no case with hypothermia had formalin pigment deposition. Comparative analyses of hypothermia and DKA cases revealed further differences: Vitreous beta-hydroxybutyrate was higher in the DKA group compared with the hypothermia group (P = 0.044), whereas blood ethanol concentrations were higher in the latter (P = 0.008). Hypothermia cases were older compared with the DKA cases (P = 0.022).When all cases were included in the statistical analysis, cases with subnuclear vacuolization had higher vitreous beta-hydroxybutyrate and blood ethanol concentrations (P = 0.029 and 0.023, respectively). The findings corroborate the results of previous studies suggesting a link between subnuclear vacuolization and increased levels of ketoacidosis.

Diet-induced Ketoacidosis in a Non-diabetic: A Case Report

Introduction

Anion gap metabolic acidosis is a common disorder seen in the emergency department. The differential can include toxicological, renal, endocrine, infectious, and cardiogenic disorders. Ketosis, however, is one of the rarer causes of metabolic acidosis seen by the emergency physician in developed nations.

Case Report

A 53-year-old female presented after starting a low-carbohydrate ketogenic diet for weight loss. She reported xerostomia, nausea with abdominal pain and a 17-pound weight loss over the previous 22 days. Labs revealed an anion-gap metabolic acidosis with ketosis. She was treated with 5% dextrose in normal saline and a sliding scale insulin coverage. Her anion gap corrected during her hospital course and was discharged on hospital day three.

Discussion

The ketogenic diet typically consists of a high-fat, adequate protein and low carbohydrate diet that has previously been thought to be relatively safe for weight loss. However, when carbohydrates are completely removed from the diet an overproduction of ketones bodies results in ketoacidosis. Treatment should be aimed at halting the ketogenic process and patient education.

Conclusion

Although rarely included in the differential for metabolic acidosis, diet-induced ketosis should be included by the emergency physician when faced with a patient who recently changed their eating patterns.

Review article: Ketoacidosis in the emergency department

Diabetic ketoacidosis, a life-threatening complication of type 1 diabetes mellitus, is a common cause of presentation to EDs. Two new drug classes have been found to cause ketoacidosis with distinctive presentations. The sodium-glucose transport protein 2 inhibitors used in the management of type 2 diabetes mellitus may present with ketoacidosis with normal glucose levels. Ketoacidosis with these medications may be prolonged and recur after initial resolution. Checkpoint inhibitors may present with fulminant diabetic ketoacidosis in individuals with previously normal glucose tolerance. Ketoacidosis may also occur as a result of starvation and alcohol excess, as well as a number of rare causes. Other causes of metabolic acidosis with both high and normal anion gap need to be considered in the differential diagnosis of ketoacidosis. Diabetic ketoacidosis may also present with biochemical changes suggestive of myocardial ischaemia and pancreatitis in the absence of these pathologies. The present paper reviews ketone body metabolism, ketone testing and the causes and differential diagnosis of ketoacidosis with particular relevance to emergency medicine.

Vitreous humor endogenous compounds analysis for post-mortem forensic investigation

The chemical and biochemical analysis of bodily fluids after death is an important thanatochemical approach to assess the cause and time since death. Vitreous humor (VH) has been used as a biofluid for forensic purposes since the 1960s. Due to its established relevance in toxicology, a literature review highlighting the use of VH with an emphasis on endogenous compounds has not yet been undertaken. VH is a chemically complex aqueous solution of carbohydrates, proteins, electrolytes and other small molecules present in living organisms; this biofluid is useful tool for its isolated environment, preserved from bacterial contamination, decomposition, autolysis, and metabolic reactions. The post-mortem analysis of VH provides an important tool for the estimation of the post-mortem interval (PMI), which can be helpful in determining the cause of death. Consequently, the present review evaluates the recent chemical and biochemical advances with particular importance on the endogenous compounds present at the time of death and their modification over time, which are valuable for the PMI prediction and to identify the cause of death.

A diabetic ketoacidosis in a context of hyperglycemia addiction

We herein present a case of a 20-year-old woman who suffered from type I diabetes mellitus and died from a diabetic ketoacidosis in a context of addiction to hyperglycemia. Diabetic ketoacidosis is a lethal complication of insulin-dependent diabetes mellitus, which can result from insulin therapy stoppage. This can occur voluntarily with suicidal intent or involuntarily due to treatment inaccessibility, forgotten injections, or material deficiency. A new possibility is investigated in our case study: hyperglycemia addiction. The patient was treated by insulin glargine and insulin aspartate. She regularly stopped insulin glargine injections seeking the asthenia sensation produced by hyperglycemia, keeping the insulin aspartate injections to treat the disabling symptom related to hyperketonemia.

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.