Disturbance of inorganic phosphate metabolism in diabetes mellitus: clinical manifestations of phosphorus-depletion syndrome during recovery from diabetic ketoacidosis

The Prevalence of Hypophosphatemia and its Associated Risk Factors in Diabetic Ketoacidosis Patients

Objective

We aimed to study the prevalence of hypophosphatemia and its associated risk factors in Diabetic Ketoacidosis (DKA) patients in the pediatric population.

Methodology

We included 65 subjects aged 7 months to 18 years old who were admitted to Hospital Universiti Sains Malaysia (HUSM) for DKA. Patients' socio-demographic and clinical characteristics, and biochemical examinations from their first admission for DKA were analyzed. The diagnosis of DKA was based on the International Society for Pediatric and Adolescent Diabetes (ISPAD) criteria. Multiple logistic regression models examined associations between different variables and hypophosphatemia.

Result

The prevalence of hypophosphatemia in DKA was highest on day 1, at 70.8%, with a mean age of 11 on presentation. Multiple logistic regression analysis showed plasma bicarbonate at day 3 [adjusted odds ratio (OR) 1.2, with a p-value of 0.027] and baseline hemoglobin [adjusted OR 0.62, with p-value 0.009] were significantly associated with hypophosphatemia during DKA.

Conclusion

The prevalence of hypophosphatemia in DKA pediatric patients admitted to our center was highest on day 1 of admission. There were many factors associated with hypophosphatemia from simple logistic regression analysis. However, our final model revealed that plasma bicarbonate on day 3 and baseline Hb were the only significant risk factors for hypophosphatemia in DKA patients in the pediatric population.

Phosphate and fibroblast growth factor 23 in diabetes

Diabetes is associated with a strongly elevated risk of cardiovascular disease, which is even more pronounced in patients with diabetic nephropathy. Currently available guideline-based efforts to correct traditional risk factors are only partly able to attenuate this risk, underlining the urge to identify novel treatment targets. Emerging data point towards a role for disturbances in phosphate metabolism in diabetes. In this review, we discuss the role of phosphate and the phosphate-regulating hormone fibroblast growth factor 23 (FGF23) in diabetes. We address deregulations of phosphate metabolism in patients with diabetes, including diabetic ketoacidosis. Moreover, we discuss potential adverse consequences of these deregulations, including the role of deregulated phosphate and glucose as drivers of vascular calcification propensity. Finally, we highlight potential treatment options to correct abnormalities in phosphate and FGF23. While further studies are needed to more precisely assess their clinical impact, deregulations in phosphate and FGF23 are promising potential target in diabetes and diabetic nephropathy.

Incidence and determinants of hypophosphatemia in diabetic ketoacidosis: an observational study

INTRODUCTION

Diabetic ketoacidosis (DKA) is a life-threatening complication of type 1 diabetes mellitus (T1DM) characterized by hyperglycemia and metabolic acidosis. Hypophosphatemia in DKA often occurs during hospital admittance for DKA. Literature on the magnitude, determinants and consequences of hypophosphatemia in DKA is scarce. Primary aim of this study was to investigate the incidence and consequences of hypophosphatemia during hospitalisation for DKA.

RESEARCH DESIGN AND METHODS

Cohort study among individuals with T1DM who were admitted for DKA between 2005 and 2020 in an academic and a non-academic hospital. Multivariate regression models were performed to investigate determinants of the lowest phosphate during the treatment of DKA.

RESULTS

A total of 127 episodes of DKA among 80 individuals were identified. Age at DKA presentation was 28 (22-46) years, 45% of the cases was female, diabetes duration was 13.2 (8.9-25.5) years with glycosylated hemoglobin levels of 91.9±26.2 mmol/mol. In 9% of all cases, DKA was the first presentation of T1DM. Lowest phosphate levelss reported during the treatment phase were 0.54 (0.32-0.83) mmol/L and hypophosphatemia was present in 74% (62/84). The time to lowest phosphate was 16 (8-23) hours. In multivariate analysis, baseline bicarbonate and hemoglobin at admission were significantly associated with the lowest phosphate level reported. No adverse effects of hypophosphatemia on hospital stay duration, morbidity or mortality were found, even if left untreated.

CONCLUSIONS

Hypophosphatemia during DKA is common and increases with severe acidosis. However, in this study it was not related to adverse outcomes. Although limitations of this retrospective study should be taken into account, the routine and repeated measurement of phosphate levels in DKA could be reconsidered, provided that possible symptoms related to hypophosphatemia are monitored.

Clinical profile and outcomes in COVID-19 patients with diabetic ketoacidosis: A systematic review of literature

BACKGROUND AND AIM

To conduct a systematic literature review and analyze the demographic/biochemical parameters and clinical outcomes of COVID-19 patients with diabetic ketoacidosis (DKA) and combined DKA/HHS (hyperglycemic hyperosmolar syndrome).

METHODS

PubMed, Scopus, Embase, and Google Scholar databases were systematically searched till August 3, 2020 to identify studies reporting COVID-19 patients with DKA and combined DKA/HHS. A total of 19 articles reporting 110 patients met the eligibility criteria.

RESULTS

Of the 110 patients, 91 (83%) patients had isolated DKA while 19 (17%) had DKA/HHS. The majority of the patients were male (63%) and belonged to black ethnicity (36%). The median age at presentation ranged from 45.5 to 59.0 years. Most of the patients (77%) had pre-existing type 2 diabetes mellitus. Only 10% of the patients had newly diagnosed diabetes mellitus. The median blood glucose at presentation ranged from 486.0 to 568.5 mg/dl, being higher in patients with DKA/HHS compared to isolated DKA. The volume of fluid replaced in the first 24 h was higher in patients with DKA/HHS in contrast to patients with DKA alone. The in-hospital mortality rate was 45%, with higher mortality in the DKA/HHS group than in the isolated DKA group (67% vs. 29%). pH was lower in patients who had died compared to those who were discharged.

CONCLUSION

DKA in COVID-19 patients portends a poor prognosis with a mortality rate approaching 50%. Differentiating isolated DKA from combined DKA/HHS is essential as the latter represents nearly one-fifth of the DKA cases and tends to have higher mortality than DKA alone.

The Association Between Hemoglobin HbA1c with Serum Inorganic Phosphate in Children with Type 1 Diabetes

BACKGROUND

Diabetes mellitus is one of the most common chronic metabolic diseases in children and adolescents, which changes the cellular metabolism. Phosphorus is an essential element for metabolism. Early in the progression of diabetes, a paradoxical metabolic imbalance in inorganic phosphate (Pi) occurs that may lead to reduced high energy phosphate and tissue hypoxia. While low and high uncontrolled blood sugars can be easily recognized by clinical symptoms, low and high plasma inorganic phosphate remain unrecognizable. Therefore, we aimed to assess the association between hemoglobin A1c (HbA1c) with serum inorganic phosphate in children with type 1 diabetes.

MATERIALS AND METHODS

This cross-sectional study was conducted on 102 patients selected from a pediatric ward in 17th Shahrivar hospital in Rasht, North of Iran. Clinical data including age, sex, height, weight, BMI, duration of diabetes, the level of HbA1c, and phosphorus were gathered. The level of HbA1c was adjusted by age in the final analysis.

RESULTS

The mean age of samples was 9.98±3.91 years old and 46 participants (45.1%) were male. It was found that HbA1c had a reversed and significant relationship with BMI (r=-0.215 and P=0.03), but there was no correlation between phosphate, age, height and weight, duration of diabetes mellitus, or rate of insulin consumption with HbA1c (P>0.05).

CONCLUSION

The finding showed that HbA1c had a reversed relationship with BMI but there was no correlation between phosphate and HbA1c.

Advances in paediatrics in 2019: current practices and challenges in allergy, endocrinology, gastroenterology, public health, neonatology, nutrition, nephrology, neurology, respiratory diseases and rheumatic diseases

We highlight the main developments that have been published during the first semester of the last year in the Italian Journal of Pediatrics. We have carefully chosen information from numerous exciting progresses issued in the Journal in the field of allergy, endocrinology, gastroenterology, neonatology, nutrition, nephrology, neurology, public health, respiratory diseases and rheumatic diseases. The impact on the care of patients has been placed in the broader context of studies that appeared in other journals. We think that many observations can be used directly to upgrade management of patients.

Diabetic ketoacidosis

Diabetic ketoacidosis (DKA) is the most common acute hyperglycaemic emergency in people with diabetes mellitus. A diagnosis of DKA is confirmed when all of the three criteria are present - 'D', either elevated blood glucose levels or a family history of diabetes mellitus; 'K', the presence of high urinary or blood ketoacids; and 'A', a high anion gap metabolic acidosis. Early diagnosis and management are paramount to improve patient outcomes. The mainstays of treatment include restoration of circulating volume, insulin therapy, electrolyte replacement and treatment of any underlying precipitating event. Without optimal treatment, DKA remains a condition with appreciable, although largely preventable, morbidity and mortality. In this Primer, we discuss the epidemiology, pathogenesis, risk factors and diagnosis of DKA and provide practical recommendations for the management of DKA in adults and children.

Circadian rhythm of activin A and related parameters of mineral metabolism in normal and uremic rats

Activin A is a new fascinating player in chronic kidney disease-mineral and bone disorder (CKD-MBD), which is implicated in progressive renal disease, vascular calcification, and osteodystrophy. Plasma activin A rises early in the progression of renal disease. Disruption of circadian rhythms is related to increased risk of several diseases and circadian rhythms are observed in mineral homeostasis, bone parameters, and plasma levels of phosphate and PTH. Therefore, we examined the circadian rhythm of activin A and CKD-MBD-related parameters (phosphate, PTH, FGF23, and klotho) in healthy controls and CKD rats (5/6 nephrectomy) on high-, standard- and low-dietary phosphate contents as well as during fasting conditions. Plasma activin A exhibited circadian rhythmicity in healthy control rats with fourfold higher values at acrophase compared with nadir. The rhythm was obliterated in CKD. Activin A was higher in CKD rats compared with controls when measured at daytime but not significantly when measured at evening/nighttime, stressing the importance of time-specific reference intervals when interpreting plasma values. Plasma phosphate, PTH, and FGF23 all showed circadian rhythms in control rats, which were abolished or disrupted in CKD. Plasma klotho did not show circadian rhythm. Thus, the present investigation shows, for the first time, circadian rhythm of plasma activin A. The rhythmicity is severely disturbed by CKD and is associated with disturbed rhythms of phosphate and phosphate-regulating hormones PTH and FGF23, indicating that disturbed circadian rhythmicity is an important feature of CKD-MBD.

Effects of diabetic ketoacidosis in the respiratory system

Diabetes affects approximately 30 million persons in the United States. Diabetes ketoacidosis is one of the most serious and acute complications of diabetes. At the time of presentation and during treatment of diabetic ketoacidosis (DKA), several metabolic and electrolyte derangements can ultimately result in respiratory compromise. Most commonly, hypokalemia, hypomagnesemia and hypophosphatemia can eventually lead to respiratory muscles failure. Furthermore, tachypnea, hyperpnea and more severely, Kussmaul breathing pattern can develop. Also, hydrostatic and non-hydrostatic pulmonary edema can occur secondary to volume shifts into the extracellular space and secondary to increased permeability of the pulmonary capillaries. The presence of respiratory failure in patients with DKA is associated with higher morbidity and mortality. Being familiar with the causes of respiratory compromise in DKA, and how to treat them, may represent better outcomes for patients with DKA.

Respiratory failure in a diabetic ketoacidosis patient with severe hypophosphatemia

Phosphate is essential in regulating human metabolic processes, and severe hypophosphatemia can induce neurologic and hematological complications and result in respiratory failure and cardiac dysfunction. Therefore, correction of severe hypophosphatemia can be pivotal in the management of diabetic ketoacidosis (DKA). We report the case of a 14-year-old female who was diagnosed with type 1 diabetes and referred to our institute for treatment of DKA. Although the patient received fluid and continuous insulin administration according to the current DKA treatment protocol, generalized tonic seizures and cardiac arrest developed. After cardiopulmonary resuscitation, the patient recovered and was stable. Within 16 hours after DKA treatment, the patient developed respiratory failure with severe hypophosphatemia that required mechanical ventilation. Concurrent neurologic evaluation revealed no specific abnormalities. The patient recovered without any complications after correcting the hypophosphatemia. We suggest vigilant monitoring of the phosphate level in DKA patients and active replacement when required.

Supraventricular tachycardia as a complication of severe diabetic ketoacidosis in an adolescent with new-onset type 1 diabetes

Diabetic ketoacidosis (DKA) is one of the most common causes of morbidity and mortality in new-onset type 1 diabetes (T1D). Supraventricular tachycardia (SVT), however, is a very rare complication of DKA. We present the case of a patient with new-onset T1D who presented with DKA. He received intravenous fluid resuscitation, insulin and potassium supplementation and subsequently developed SVT, confirmed on a 12-lead electrocardiograph despite a structurally normal heart. Vagal manoeuvres and adenosine failed to restore sinus rhythm, but flecainide was successful. We conclude that SVT can occur as a complication of DKA, including in new-onset T1D. Our case is the first of this phenomenon occurring in new-onset childhood diabetes, as the few prior documented cases had established diabetes. Furthermore, a combination of potassium derangement, hypophosphataemia and falling magnesium levels may have precipitated the event.

Respiratory failure in diabetic ketoacidosis

Respiratory failure complicating the course of diabetic ketoacidosis (DKA) is a source of increased morbidity and mortality. Detection of respiratory failure in DKA requires focused clinical monitoring, careful interpretation of arterial blood gases, and investigation for conditions that can affect adversely the respiration. Conditions that compromise respiratory function caused by DKA can be detected at presentation but are usually more prevalent during treatment. These conditions include deficits of potassium, magnesium and phosphate and hydrostatic or non-hydrostatic pulmonary edema. Conditions not caused by DKA that can worsen respiratory function under the added stress of DKA include infections of the respiratory system, pre-existing respiratory or neuromuscular disease and miscellaneous other conditions. Prompt recognition and management of the conditions that can lead to respiratory failure in DKA may prevent respiratory failure and improve mortality from DKA.

Disturbance of inorganic phosphate metabolism in diabetes mellitus: its relevance to the pathogenesis of diabetic retinopathy

Early in the progression of diabetes, a paradoxical metabolic imbalance in inorganic phosphate (Pi) occurs that may lead to reduced high energy phosphate and tissue hypoxia. These changes take place in the cells and tissues in which the entry of glucose is not controlled by insulin, particularly in poorly regulated diabetes patients in whom long-term vascular complications are more likely. Various conditions are involved in this disturbance in Pi. First, the homeostatic function of the kidneys is suboptimal in diabetes, because elevated blood glucose concentrations depolarize the brush border membrane for Pi reabsorption and lead to lack of intracellular phosphate and hyperphosphaturia. Second, during hyperglycemic-hyperinsulinemic intervals, high amounts of glucose enter muscle and fat tissues, which are insulin sensitive. Intracellular glucose is metabolized by phosphorylation, which leads to a reduction in plasma Pi, and subsequent deleterious effects on glucose metabolism in insulin insensitive tissues. Hypophosphatemia is closely related to a decrease in adenosine triphosphate (ATP) in the aging process and in uremia. Any interruption of optimal ATP production might lead to cell injury and possible cell death, and evidence will be provided herein that such cell death does occur in diabetic retinopathy. Based on this information, the mechanism of capillary microaneurysms formation in diabetic retinopathy and the pathogenesis of diabetic retinopathy must be reevaluated.