Toxigenic and Metabolic Causes of Ketosis and Ketoacidotic Syndromes

Ketoacidosis and SGLT2 Inhibitors: A Narrative Review

An acute metabolic complication of diabetes mellitus, especially type 1, is diabetic ketoacidosis (DKA), which is due to an increase in blood ketone concentrations. Sodium/glucose co-transporter-2 inhibitor (SGLT2-i) drugs have been associated with the occurrence of a particular type of DKA defined as euglycemic (euDKA), characterized by glycemic levels below 300 mg/dL. A fair number of euDKA cases in SGLT2-i-treated patients have been described, especially in the last few years when there has been a significant increased use of these drugs. This form of euDKA is particularly insidious because of its latent onset, associated with unspecific symptomatology, until it evolves (progressing) to severe systemic forms. In addition, its atypical presentation can delay diagnosis and treatment. However, the risk of euDKA associated with SGLT2-i drugs remains relatively low, but it is essential to promptly diagnose and manage it to prevent its serious life-threatening complications. In this narrative review, we intended to gather current research evidence on SGLT2i-associated euDKA from randomized controlled trials and real-world evidence studies, its diagnostic criteria and precipitating factors.

Eu- or hypoglycemic ketosis and ketoacidosis in children: a review

The last decade has been characterized by exciting findings on eu- or hypoglycemic ketosis and ketoacidosis. This review emphasizes the following five key points: 1. Since the traditional nitroprusside-glycine dipstick test for urinary ketones is often falsely negative, the blood determination of β-hydroxybutyrate, the predominant ketone body, is currently advised for a comprehensive assessment of ketone body status; 2. Fasting and infections predispose to relevant ketosis and ketoacidosis especially in newborns, infants, children 7 years or less of age, and pregnant, parturient, or lactating women; 3. Several forms of carbohydrate restriction (typically less than 20% of the daily caloric intake) are employed to induce ketosis. These ketogenic diets have achieved great interest as antiepileptic treatment, in the management of excessive body weight, diabetes mellitus, and in sport training; 4. Intermittent fasting is more and more popular because it might benefit against cardiovascular diseases, cancers, neurologic disorders, and aging; 5. Gliflozins, a new group of oral antidiabetics inhibiting the renal sodium-glucose transporter 2, are an emerging cause of eu- or hypoglycemic ketosis and ketoacidosis. In conclusion, the role of ketone bodies is increasingly recognized in several clinical conditions. In the context of acid-base balance evaluation, it is advisable to routinely integrate both the assessment of lactic acid and β-hydroxybutyrate.

Succinate prodrugs as treatment for acute metabolic crisis during fluoroacetate intoxication in the rat

Sodium fluoroacetate (FA) is a metabolic poison that systemically inhibits the tricarboxylic acid (TCA) cycle, causing energy deficiency and ultimately multi-organ failure. It poses a significant threat to society because of its high toxicity, potential use as a chemical weapon and lack of effective antidotal therapy. In this study, we investigated cell-permeable succinate prodrugs as potential treatment for acute FA intoxication. We hypothesized that succinate prodrugs would bypass FA-induced mitochondrial dysfunction, provide metabolic support, and prevent metabolic crisis during acute FA intoxication. To test this hypothesis, rats were exposed to FA (0.75 mg/kg) and treated with the succinate prodrug candidate NV354. Treatment efficacy was evaluated based on cardiac and cerebral mitochondrial respiration, mitochondrial content, metabolic profiles and tissue pathology. In the heart, FA increased concentrations of the TCA metabolite citrate (+ 4.2-fold, p < 0.01) and lowered ATP levels (- 1.9-fold, p < 0.001), confirming the inhibition of the TCA cycle by FA. High-resolution respirometry of cardiac mitochondria further revealed an impairment of mitochondrial complex V (CV)-linked metabolism, as evident by a reduced phosphorylation system control ratio (- 41%, p < 0.05). The inhibition of CV-linked metabolism is a novel mechanism of FA cardiac toxicity, which has implications for drug development and which NV354 was unable to counteract at the given dose. In the brain, FA induced the accumulation of β-hydroxybutyrate (+ 1.4-fold, p < 0.05) and the reduction of mitochondrial complex I (CI)-linked oxidative phosphorylation (OXPHOSCI) (- 20%, p < 0.01), the latter of which was successfully alleviated by NV354. This promising effect of NV354 warrants further investigations to determine its potential neuroprotective effects.

Plasma metabolomics of oral squamous cell carcinomas based on NMR and MS approaches provides biomarker identification and survival prediction

Metabolomics has proven to be an important omics approach to understand the molecular pathways underlying the tumour phenotype and to identify new clinically useful markers. The literature on cancer has illustrated the potential of this approach as a diagnostic and prognostic tool. The present study aimed to analyse the plasma metabolic profile of patients with oral squamous cell carcinoma (OSCC) and controls and to compare patients with metastatic and primary tumours at different stages and subsites using nuclear magnetic resonance and mass spectrometry. To our knowledge, this is the only report that compared patients at different stages and subsites and replicates collected in diverse institutions at different times using these methodologies. Our results showed a plasma metabolic OSCC profile suggestive of abnormal ketogenesis, lipogenesis and energy metabolism, which is already present in early phases but is more evident in advanced stages of the disease. Reduced levels of several metabolites were also associated with an unfavorable prognosis. The observed metabolomic alterations may contribute to inflammation, immune response inhibition and tumour growth, and may be explained by four nonexclusive views-differential synthesis, uptake, release, and degradation of metabolites. The interpretation that assimilates these views is the cross talk between neoplastic and normal cells in the tumour microenvironment or in more distant anatomical sites, connected by biofluids, signalling molecules and vesicles. Additional population samples to evaluate the details of these molecular processes may lead to the discovery of new biomarkers and novel strategies for OSCC prevention and treatment.

Examination of Postmortem β-Hydroxybutyrate Increase in Forensic Autopsy Cases

Ketoacidosis is one of the common diseases that sometimes result in death. In forensic autopsy cases, the measuring of ketone bodies, especially β-hydroxybutyrate (BHB), is useful in diagnosing postmortem ketoacidosis as a cause of death. However, increased BHB values are not always indicative of ketoacidosis. Other causes of death, such as hypothermia, are known to increase BHB values. In addition, sometimes, we experience cases of increased BHB values that are unlikely to be associated with the pathophysiology or the cause of death resulting in an increase in BHB values. In this study, autopsies were performed to determine the relationship between blood BHB values and the postmortem interval (PMI). The patients were divided into four groups: PMI ≤ 24 h, PMI ≤ 48 h, PMI ≤ 72 h, and PMI > 72 h. The BHB values for each group were then compared. Based on the analysis, patients with a PMI ≤ 72 h and those with a PMI > 72 h had significantly higher BHB values than patients with a PMI ≤ 24 h. In conclusion, there remains a possibility that the BHB values increase after death. Forensic pathologists should consider PMI when diagnosing ketoacidosis as the cause of death.

Measuring ketone bodies for the monitoring of pathologic and therapeutic ketosis

BACKGROUND

The ketone bodies β-hydroxybutyrate (BOHB) and acetone are generated as a byproduct of the fat metabolism process. In healthy individuals, ketone body levels are ∼0.1 mM for BOHB and ∼1 part per million for breath acetone (BrAce). These levels can increase dramatically as a consequence of a disease process or when used therapeutically for disease treatment. For example, increased ketone body concentration during weight loss is an indication of elevated fat metabolism. Ketone body measurement is relatively inexpensive and can provide metabolic insights to help guide disease management and optimize weight loss.

METHODS

This review of the literature provides metabolic mechanisms and typical concentration ranges of ketone bodies, which can give new insights into these conditions and rationale for measuring ketone bodies.

RESULTS

Diseases such as heart failure and ketoacidosis can affect caloric intake and macronutrient management, which can elevate BOHB 30-fold and BrAce 1000-fold. Other diseases associated with obesity, such as brain dysfunction, cancer, and diabetes, may cause dysfunction because of an inability to use glucose, excessive reliance on glucose, or poor insulin signaling. Elevating ketone body concentrations (e.g., nutritional ketosis) may improve these conditions by forcing utilization of ketone bodies, in place of glucose, for fuel. During weight loss, monitoring ketone body concentration can demonstrate program compliance and can be used to optimize the weight-loss plan.

CONCLUSIONS

The role of ketone bodies in states of pathologic and therapeutic ketosis indicates that accurate measurement and monitoring of BOHB or BrAce will likely improve disease management. Bariatric surgery is examined as a case study for monitoring both types of ketosis.

Characterization and outcome of 11 children with non-diabetic ketoacidosis

OBJECTIVES

To study the clinical and laboratory features, management, and outcome of pediatric non-diabetic ketoacidosis (NDKA).

METHODS

Between May 2018 and April 2020, we prospectively collected children under 18 years who presented with ketoacidosis, defined as ketosis (urinary ketones ≥++ and/or serum β-hydroxybutyrate level ≥3 mmol/L) and metabolic acidosis (pH <7.3 and HCO₃ ^- <15 mmol/L). Children with HbA1c level ≥6.5% at initial presentation and those meeting the diagnostic criteria for DM during follow-up were excluded. Data were collected on demographics, clinical and laboratory features, management, and outcome.

RESULTS

Eleven children with 19 episodes of NDKA were identified. The median age was 12 months (range from 5 months to 5 years). They manifested dehydration and disturbed conscious level (all cases), convulsions (n=6), hypoglycemia (n=6), hyperglycemia (n=2) and significant hyperammonemia (n=4). Most cases required intensive care management. Death or neurodevelopmental impairment occurred in six cases. Seven cases had inborn errors of metabolism (IEMs). Other cases were attributed to starvation, sepsis, and salicylate intoxication.

CONCLUSIONS

This is the largest case series of pediatric NDKA. Ketoacidosis, even with hyperglycemia, is not always secondary to diabetes mellitus. IEMs may constitute a significant portion of pediatric NDKA. Increased awareness of this unfamiliar condition is important for prompt diagnosis, timely management, and better outcome.

Non-diabetic ketoacidosis associated with a low carbohydrate, high fat diet in a postpartum lactating female

A 31-year old non-diabetic woman presented to our hospital with symptoms of dehydration, drowsiness, fatigue, shortness of breath and vomiting present for two consecutive days prior to admission. She had started a low carbohydrate, high fat (LCHF) diet to induce weight loss while breastfeeding her 4-month-old child 2 weeks prior to admission. The patient was found to have a severely high anion gap metabolic acidosis. It was determined to be due to ketoacidosis, which was as a result of carbohydrate restriction in the presence of increased metabolic demands related with the synthesis and secretion of milk. She denied alcohol use or ingestion of any drugs prior to admission. The patient underwent dialysis and received insulin, 5% dextrose water alongside a well-balanced diet with adequate calories. All abnormal laboratory results normalized and follow-up visits were done. Lactating women are at risk of developing ketoacidosis due to high metabolic demands of the body to produce milk. LCHF diets may exacerbate the body's demand to meet its milk production requirement and result in ketoacidosis. Health professionals need to be aware of the complications of LCHF diet in this population to prevent mortality associated with this condition.

Review article: Accelerated starvation of childhood: Have I judged ketones?

Acute ketosis is an important physiological mechanism to prevent irreversible neurological damage from hypoglycaemia during starvation, and represents a significant metabolic stress. A cohort of children adapt to relatively short periods of reduced caloric intake by generating large quantities of ketone bodies. When excessive, the gastrointestinal symptoms of starvation ketosis such as nausea and pain may create a vicious cycle that delays spontaneous resolution. The presence of ketones can be dismissed as a normal feature of childhood metabolism, sometimes even when extreme. A broader understanding of this process under the banner of 'accelerated starvation of childhood' is helpful for clinicians managing acute illness in children. We advocate that children less than 7 years of age with a history suggestive of accelerated starvation of childhood should be screened by emergency clinicians for ketosis using a simple and cheap bedside capillary test, even if glucose levels are greater than 2.6 mmol/L. Identification and appropriate management of ketosis may alleviate the distressing gastrointestinal symptoms associated with many minor illnesses, and potentially prevent hypoglycaemia in some children. Appropriate advice to carers may be helpful to prevent further episodes. Illustrative case examples from our own practice are provided.

Acute liver failure in two dogs following ingestion of cheese tree (Glochidion ferdinandi) roots

OBJECTIVE

To describe the management and resolution of acute liver failure (ALF) in two dogs following ingestion of cheese tree (Glochidion ferdinandi) roots.

CASE SUMMARIES

A 2-year-old male entire Bullmastiff and a 5-year-old female neutered German Shepherd dog were presented for acute-onset lethargy and vomiting after chewing on tree roots of a cheese tree. Both dogs developed clinical abnormalities consistent with ALF, including hepatic encephalopathy, marked increase in alanine aminotransferase activity and bilirubin concentration, and prolonged coagulation times. Treatment included administration of intravenous fluids, hepatoprotectants, vitamin K₁ , antibiotics, lactulose, antacids, antiemetics, and multiple fresh frozen plasma transfusions. Follow-up examinations performed 30 days after initial presentation revealed the dogs to be clinically healthy with serum biochemical and coagulation profiles within reference intervals.

NEW OR UNIQUE INFORMATION

This is the first report describing ALF in two dogs following ingestion of cheese tree (G. ferdinandi) roots. In this clinical setting, despite a poor prognosis, survival and recovery of adequate liver function were possible with medical management.

Hyperkalemia in patients treated with endoradiotherapy combined with amino acid infusion is associated with severe metabolic acidosis

Background

Amino acid co-infusion for renal protection in endoradiotherapy (ERT) applied as prostate-specific membrane antigen (PSMA)-targeted radioligand therapy (RLT) or peptide receptor radionuclide therapy (PRRT) has been shown to cause severe hyperkalemia. The pathophysiology behind the rapid development of hyperkalemia is not well understood. We hypothesized that the hyperkalemia should be associated with metabolic acidosis.

Results

Twenty-two patients underwent ERT. Prior to the first cycle, excretory kidney function was assessed by mercapto-acetyltriglycine (MAG-3) renal scintigraphy, serum biochemistry, and calculated glomerular filtration rate (eGFR). All patients received co-infusion of the cationic amino acids L-arginine and L-lysine for nephroprotection. Clinical symptoms, electrolytes, and acid-base status were evaluated at baseline and after 4 h.

No patient developed any clinically relevant side effects. At baseline, acid base status and electrolytes were normal in all patients. Excretory kidney function was normal or only mildly impaired in all except two patients with stage 3 renal insufficiency. All patients developed hyperkalemia. Base excess and HCO₃⁻ were significantly lower after 4 h. In parallel, mean pH dropped from 7.36 to 7.29. There was a weak association between calculated (r = − 0.21) as well as MAG-3-derived GFR (r = − 0.32) and the rise in potassium after 4 h.

Conclusion

Amino acid co-infusion during ERT leads to severe metabolic acidosis which induces hyperkalemia by potassium hydrogen exchange. This novel finding implies that commercially available bicarbonate solutions might be an easy therapeutic option to correct metabolic acidosis rapidly.

Electronic supplementary material

The online version of this article (10.1186/s13550-018-0370-z) contains supplementary material, which is available to authorized users.

Effects of feeding drunken horse grass infected with Epichloë gansuensis endophyte on animal performance, clinical symptoms and physiological parameters in sheep

BACKGROUND

Many reports showed that grass-endophyte symbiosis induced livestock poisoned. Yet, there is no study evaluating clinical symptoms and physiological parameters in sheep fed Epichloë gansuensis endophyte-infected grass. The objective of the present study was to investigate these indexes by feeding sheep with endophyte-infected A. inebrians (E+ Group) or endophyte-free A. inebrians (E- Group) drunken horse grass or alfalfa hay (Control Group).

RESULTS

The Epichloë endophyte caused obvious toxicity symptoms in the sheep fed E+ A. inebrians, with 1 of the 5 sheep having died by the 35th day. The feed intake and body weight gain of the E+ Group were significantly less than the E- and control groups (P < 0.05). Serum concentrations of alanine aminotransferase (ALT, 45.5 mmol/L) and aspartate aminotransferase for the E+ group (AST, 139.3 mmol/L) were significantly (P < 0.05) greater than for the E- (ALT, 31.2 mmol/L; AST, 78.6 mmol/L) and control (ALT, 32.6 mmol/L; AST, 56.6 mmol/L) groups at the fifth week; serum concentration of creatinine for the E+ group (63.8 mmol/L) was also significantly (P < 0.05) greater than for E- (56.6 mmol/L) and control groups (58.5 mmol/L). Meanwhile, urine biochemical indices for the E+ group indicated that ketone and occult blood were significantly (P < 0.05) elevated compared to the other groups while urine pH values were significantly (P < 0.05) acidic. The relative weight of heart, brain, liver, lung and kidney for Group E+ were almost two fold more than the other groups, but uterus weight was about half that found for Group E- or Control.

CONCLUSIONS

We conclude that the Epichloë endophyte infection is the cause of A. inebrians toxicity to sheep. Interestingly, none of the measured parameters differed significantly between E- and the control groups, which implied that drunken horse grass could be utilized efficiently by sheep when not infected by the Epichloë endophyte.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY POSITION STATEMENT ON THE ASSOCIATION OF SGLT-2 INHIBITORS AND DIABETIC KETOACIDOSIS

ABBREVIATIONS

AACE = American Association of Clinical Endocrinologists ACE = American College of Endocrinology DKA = diabetic ketoacidosis EMA = European Medicines Agency FDA = U.S. Food and Drug Administration SGLT-2 = sodium glucosecotransporter 2 T1D = type 1 diabetes T2D = type 2 diabetes.

Quantitative Clinical Diagnostic Analysis of Acetone in Human Blood by HPLC: A Metabolomic Search for Acetone as Indicator

Using high-performance liquid chromatography (HPLC) and 2,4-dinitrophenylhydrazine (2,4-DNPH) as a derivatizing reagent, an analytical method was developed for the quantitative determination of acetone in human blood. The determination was carried out at 365 nm using an ultraviolet-visible (UV-Vis) diode array detector (DAD). For acetone as its 2,4-dinitrophenylhydrazone derivative, a good separation was achieved with a ThermoAcclaim C18 column (15 cm × 4.6 mm × 3 μm) at retention time (t R) 12.10 min and flowrate of 1 mL min(-1) using a (methanol/acetonitrile) water elution gradient. The methodology is simple, rapid, sensitive, and of low cost, exhibits good reproducibility, and allows the analysis of acetone in biological fluids. A calibration curve was obtained for acetone using its standard solutions in acetonitrile. Quantitative analysis of acetone in human blood was successfully carried out using this calibration graph. The applied method was validated in parameters of linearity, limit of detection and quantification, accuracy, and precision. We also present acetone as a useful tool for the HPLC-based metabolomic investigation of endogenous metabolism and quantitative clinical diagnostic analysis.

Beta-hydroxybutyrate Concentrations in Dogs with Acute Pancreatitis and Without Diabetes Mellitus

BACKGROUND

β-hydroxybutyrate (BOHB) concentrations have not been quantified in dogs with acute pancreatitis (AP).

OBJECTIVE

The aim of this study was to investigate BOHB concentrations in dogs with AP.

ANIMALS

A total of 154 client-owned dogs without DM.

METHODS

Prospective clinical study. Dogs were enrolled into 1 of 3 groups: AP, sick without an AP diagnosis, or fasted. Dogs were diagnosed with AP (44) if they had vomiting or anorexia, and either ultrasonographic findings consistent with AP or increased pancreatic lipase. Sick dogs without AP (68) had vomiting or anorexia but a diagnosis of AP was either not suspected or was excluded based on ultrasonographic findings or a normal pancreatic lipase. Dogs without anorexia or vomiting that were fasted for over 10 hours for a procedure were also enrolled (42). BOHB was measured on whole blood with a portable ketone meter. The Kruskal-Wallis test was performed to compare BOHB in the 3 groups. Pair-wise comparisons were performed using the Mann-Whitney test and Bonferroni corrected P-values are reported.

RESULTS

Median BOHB concentration was significantly higher in dogs with AP (0.3 mmol/L, range 0-2.9 mmol/L) compared to sick dogs without AP (0.20 mmol/L, range 0-0.9 mmol/L, P = .007) and fasted dogs (0.1 mmol/L, range 0-0.4 mmol/L, P = .0001). Median BOHB concentration was significantly higher in sick dogs without AP compared to fasted dogs (P = .0002).

CONCLUSIONS AND CLINICAL IMPORTANCE

In dogs without DM, BOHB is significantly higher in dogs with AP compared to other dogs. The diagnostic utility of this finding remains to be investigated.

Lactation Ketoacidosis: An Unusual Entity and a Review of the Literature

A 31-year-old woman presented to the hospital with symptoms of nausea, malaise, and emesis. She was breastfeeding her 10-month-old infant. She was found to have severe ketoacidosis. The patient was not in diabetic ketoacidosis or alcoholic ketoacidosis; nor had she ingested any toxins. After she was admitted to the hospital, received intravenous fluids, and stopped breastfeeding, her symptoms resolved. She was found to have lactation ketoacidosis, an uncommon condition in humans. A review of all causes of ketoacidosis is presented with special emphasis on lactation ketocacidosis.

Interventions for preventing or treating malnutrition in problem drinkers who are homeless or vulnerably housed: protocol for a systematic review

BACKGROUND

Problem alcohol drinking in homeless and vulnerably housed people can lead to malnutrition, which is associated with complications such as alcohol-related brain damage. Homeless alcohol drinkers are likely to have worse health outcomes and different nutritional needs compared with housed alcohol-drinking persons. It is not clear whether interventions to improve nutritional status in this population have been effective. The purpose of this review is to assess the effectiveness and cost-effectiveness of interventions for preventing or correcting micronutrient deficiencies and other forms of malnutrition and related comorbidities in this population.

METHODS/DESIGN

A systematic search for studies of a nutrition-based intervention applied in the homeless or vulnerably housed population with problem drinking will be conducted. The following electronic databases will be systematically searched for relevant studies: MEDLINE, EMBASE, Web of Science, PsycINFO, CAB abstracts, CINAHL, Cochrane Public Health Group Register and Cochrane Drugs and Alcohol Group Register. Screening of identified abstracts for relevance and assessment of papers for inclusion will be done in duplicate. One reviewer will extract data from the studies and assess quality, and this will be checked by another reviewer. Discrepancies will be resolved by consensus. The primary outcomes are (mal)nutrition status or micronutrient deficiencies or change in (mal)nutrition status or micronutrient deficiencies, measures of liver damage and cognitive function. Secondary outcomes include comorbidities, quality of life and functional scales, resources used to deliver treatment, uptake/acceptability of the intervention and engagement with treatment services. Results will be analysed descriptively, and, if appropriate, meta-analyses will be performed.

DISCUSSION

The results of this review should help to inform the development of effective interventions that can be implemented in the community to improve the health of homeless people who are problem drinkers.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015024247.

Bilateral putaminal necrosis and bronopol toxicity

Among alcohols, methanol intoxication is the most frequently associated with cerebral toxicity, causing retinal damage and putaminal necrosis. This consequence is believed to be due to the transformation of methanol into formic acid. We describe the case of a patient who presented with acute impairment of consciousness and tetraparesis after she had been drinking several bottles of a topical antiseptic solution (Lysoform Medical) containing 2-bromo-2-nitro-1,3-propandiol (bronopol) among excipients, in order to lose weight during previous months. Moreover, she had been on a strict slimming diet. Soon after admission, a severe respiratory and metabolic impairment became rapidly evident, requiring an intensive care unit admission. Cerebral MRI showed the presence of bilateral putaminal necrosis. She recovered in 10 days, surprisingly, without any evident clinical neurological signs. Methanol, also bronopol, when diluted in aqueous solution, at warm temperature and/or higher pH, may release formaldehyde, which is converted into formic acid, a basal ganglia toxic compound.

Septic ketoacidosis

Various unmeasured anions other than lactate appear in the blood of septic patients, including ketones. However, the occurrence of sepsis-induced ketoacidosis without diabetes mellitus has not been reported to date. We herein describe severe ketoacidosis in a patient with septic shock despite the absence of diabetes, alcohol and starvation. A 76-year-old woman presented with septic shock due to acute obstructive cholangitis. She exhibited ketoacidosis and a remarkably strong ion gap, except for ketones. Sepsis alone may lead to ketoacidosis in patients without diabetes under specific conditions. The accumulation of ketones and other strong anions can occur in cases involving a decreased metabolic function. There may be a pathological condition called septic ketoacidosis.