Prediction of Micro- and Macrovascular Complications in Type 2 Diabetes Mellitus using Heart Rate Variability.

OBJECTIVE: To explore the utility of heart rate variability (HRV), a noninvasive marker of cardiac autonomic activity, as a prescreening tool for the prediction of micro- and macrovascular complications in type 2 diabetes mellitus (T2DM). METHODS: Consenting type 2 diabetic patients of both genders between 30 and 70 years, without known micro- and macrovascular complications of diabetes, were enrolled. Patients with medications affecting the HRV were excluded. Prior to other screening tests, 15 minutes of resting electrocardiogram (ECG) (1 kHz) was recorded in enrolled patients, followed by an exercise stress test and assessment for nephropathy, retinopathy, and peripheral neuropathy. The patients with positive stress tests were referred for coronary angiography to confirm coronary artery disease. Based on screening test results, patients were grouped as Group I-T2DM without complications (n = 31) and Group II-T2DM with micro/macrovascular complications (n = 29), (total = 60). RESULTS: Group comparison and test for association were employed, and p-value of <0.05 was considered significant. Significantly reduced HRV (decreased standard deviation of NN interval) between groups and a strong association of HRV indices with complications of diabetes were observed. Logistic regression to classify complicated vs noncomplicated group was used, and an accuracy of 0.78 with 85% sensitivity, 74% specificity with area under the curve (AUC) of 0.83 was observed. CONCLUSION: Significantly reduced HRV, stronger association with complications, and 85% sensitivity, 74% specificity, and 78% accuracy of classification make HRV indices a promising prescreening tool to predict micro- and macrovascular complications in type 2 diabetes.

Rickettsia parkeri Rickettsiosis in Kidney Transplant Recipient, North Carolina, USA, 2023.

Spotted fever rickettsiosis is rarely observed in solid organ transplant recipients, and all previously reported cases have been associated with tick bite months to years after transplantation. We describe a kidney transplant recipient in North Carolina, USA, who had a moderately severe Rickettsia parkeri infection develop during the immediate posttransplant period.

Review of intravitreal VEGF inhibitor toxicity and report of collapsing FSGS with TMA in a patient with age-related macular degeneration.

Intravitreal vascular endothelial growth factor (VEGF) receptor blockade is used for a variety of retinal pathologies. These include age-related macular degeneration (AMD), diabetic macular edema (DME) and central retinal vein obstruction. Reports of absorption of intravitreal agents into systemic circulation have increased in number and confirmation of depletion of VEGF has been confirmed. Increasingly there are studies and case reports showing worsening hypertension, proteinuria, renal dysfunction and glomerular disease. The pathognomonic findings of systemic VEGF blockade, thrombotic microangiopathies (TMAs), are also being increasingly reported. One lesion that occurs in conjunction with TMAs that has been described is collapsing focal segmental glomerulosclerosis (cFSGS). cFSGS has been postulated to occur due to TMA-induced chronic glomerular hypoxia. In this updated review we discuss the mechanistic, pharmacological, epidemiological and clinical evidence of intravitreal VEGF toxicity. We review cases of biopsy-proven toxicity presented by our group and other investigators. We also present the third reported case of cFSGS in the setting of intravitreal VEGF blockade with a chronic TMA component that was crucially found on biopsy. This patient is a 74-year-old nondiabetic male receiving aflibercept for AMD. Of the two prior cases of cFSGS in the setting of VEGF blockade, one had AMD and the other had DME. This case solidifies the finding of cFSGS and its association with chronic TMA as a lesion that may be frequently encountered in patients receiving intravitreal VEGF inhibitors.

Osmotic Nephrosis and Acute Kidney Injury Associated With SGLT2 Inhibitor Use: A Case Report.

We report a case of a patient who developed dialysis-requiring acute kidney injury (AKI) after the use of canagliflozin. A 66-year-old man with type 2 diabetes who was recovering from left knee septic arthritis at a rehabilitation facility was admitted with oliguric AKI 5 days after starting treatment with canagliflozin, an inhibitor of sodium/glucose cotransporter 2 (SGLT2). The patient presented with hematuria, non-nephrotic-range proteinuria, and serum creatinine level of 6.8 (baseline, 1.1-1.3) mg/dL. There was no recent use of radiocontrast agents or exposure to other nephrotoxins. The patient subsequently required hemodialysis. Due to recent antibiotic use (ampicillin-sulbactam), acute interstitial nephritis was considered in the differential diagnosis. Kidney biopsy was performed, which showed the presence of osmotic nephropathy. The patient's kidney function returned to baseline after 2 weeks of hemodialysis. This case provides evidence of an association of osmotic nephropathy with the use of canagliflozin and discusses potential mechanisms. We recommend kidney biopsy for cases of severe AKI associated with SGLT2 inhibitors to better understand the relationship of this complication with the use of this class of medications.

Historical Milestones in Peritoneal Dialysis.

Two and a half centuries have passed since the therapeutic use of peritoneal cavity for the treatment of ascites by peritoneal lavage was reported. George Ganter was the first to describe the use of peritoneal dialysis (PD) in humans. This chapter will describe the various milestones in the field of PD achieved over the years. These include the understanding of solute and water transport across the peritoneal membrane, developments in PD technique and technology, progress in the prevention and treatment of infections, and other important milestones.

Vancomycin-Associated Acute Kidney Injury with a Steep Rise in Serum Creatinine.

BACKGROUND: Vancomycin-associated (VA) acute kidney injury (AKI) is being increasingly recognized. A distinct pattern of rapid rise in serum creatinine (sCr) during VA-AKI has occasionally been observed. However, such scenarios remain underreported. METHODS: We conducted an online survey at the American Society of Nephrology Communities forum and reviewed publications of VA-AKI via PubMed or Google searching for cases of precipitous AKI (those with rise in sCr ≥1.5 mg/dL/day) attributable to vancomycin. RESULTS: We identified 12 original cases compiled from 6 different hospitals and 4 published cases (n = 16; 38% women, age 43.5 ± 16 years, weight 108 ± 23 kg, body mass index 35 ± 7 kg/m2) of precipitous AKI observed shortly after large cumulative doses of VA (8.8 ± 5 g). The median steepest 24-h rise in sCr was 2.6 mg/dL (range 1.5-3.5 mg/dL) and the slope of the initial 48-h sCr rise was greater than that of a control AKI (non-VA, n = 48) group (2.03 ± 0.1 vs. 0.62 ± 0.0 mg/dL/day; p < 0.0001). The steep rise in sCr in the VA-AKI was not accompanied by anuria. Overt rhabdomyolysis was absent in all cases. Further, in 3 precipitous VA-AKI cases, simultaneous serum cystatin C values did not rise precipitously, suggesting that the reductions in glomerular filtration rate were overestimated by the sCr increase. CONCLUSIONS: VA-AKI can manifest with a precipitous rise in sCr shortly after a high cumulative dose of vancomycin. True toxic tubular injury overrepresented by the sCr rise is postulated.

Acute Cardiac Tamponade: An Unusual Cause of Acute Renal Failure.

We are reporting a case of acute renal failure after cardiac surgery due to acute pericardial effusion. The patient had normal baseline renal function but developed acute oliguric renal failure with a significant increase in serum creatinine postoperatively. Pericardiotomy led to an improvement in blood pressure, immediate diuresis and quick recovery of renal function back to baseline. Pericardial tamponade should be included in the consideration of causes of the cardiorenal syndrome.

Postprostatectomy seizures: A case report.

A 75-year-old Caucasian male presented with generalized seizures half-hour post-transurethral resection of the prostate surgery. The intra-operative course was complicated by perforation of the posterior wall of the bladder neck during a difficult Foley catheter placement. This resulted in intraperitoneal extravasation of the glycine containing bladder irrigation fluid. An emergent laparotomy was performed, and 3.5-4 L of fluid was drained from the peritoneal cavity. Postoperative course was complicated by two seizures within a short interval. Patient developed profound hyponatremia (Na of 109 mEq/L). However, measured serum osmolality was normal (283 mOsm/kg). The serum osmolality remained relatively stable, indicating that the absorbed glycine and its metabolites remained osmotically active in the intravascular space (until they were dialyzed as mentioned later), making the hyponatremia less pernicious and an unlikely cause of patient's symptoms. The encephalopathy and seizures were ascribed to accumulation of toxic metabolites of glycine, especially ammonia (serum level -1261 mcmol/L). During a complicated postoperative period, patient developed oligo-anuric renal failure, and was started on slow low-efficiency dialysis for 8 hours resulting in rapid lowering of serum ammonia levels and glycine with reversal of encephalopathy including seizures. There was no recurrence of encephalopathy, seizures, or metabolic acidosis. Although rare, glycine toxicity may be life threatening. The pathophysiology, need for early detection and the role of early use of renal replacement therapy in acute glycine toxicity is discussed below.

A patient with hemoptysis and renal failure.

Pulmonary-renal syndrome is a medical emergency; etiology of which has broad differential diagnosis. Delay in both diagnosis and initiation of management may result in end-organ damage. Management decisions may have to be empiric till a rapid, definitive tissue diagnosis is established. We present such a case where prompt recognition and immediate treatment was initiated, although the patient sustained irreversible end-organ damage. The case also highlights the need to interpret the kidney biopsy data (namely, immunofluroscence findings) in the context of clinical presentation.

Cardio-renal syndrome.

In today's clinical practice, a physician takes care of increasing number of patients with both cardiac and renal dysfunction. Due to our increased understanding of pathogenesis of cardiac dysfunction in patients with renal failure and vice versa, the definition of Cardio-Renal Syndrome has undergone a change. This article discusses briefly the types and pathogenesis of the Cardio-Renal Syndromes.

Renal replacement therapies.

The kidneys perform a wide array of functions in the body, most of which are essential for life. Regulation of water and electrolytes, excretion of metabolic waste and of bioactive substances like hormones, drugs etc., which affect bodily functions; regulation of arterial blood pressure, red blood cell and vitamin D production; are some of the major functions that the kidneys perform. It is obvious then, that patients with renal failure present a steep challenge to the physician taking care of this special population. Renal replacement therapy remains only a part of treatment that helps substitute the regulation of water and electrolytes, removal of metabolic waste, and to a certain extent removal of drugs and other bioactive substances from the body. This article aims to provide an understanding of different types of renal replacement therapy, mainly to patients with end-stage renal disease (ESRD).

Acquired factor VIII inhibitor in a nonhemophilia patient on hemodialysis: challenges in management.

It is well known that the uremic milieu predisposes patients to an increased risk of bleeding. We report a case of a patient on hemodialysis who developed recurrent unexplained bleeding episodes. His renal failure was secondary to systemic lupus erythematosus. Further investigations revealed that his bleeding was secondary to the development of acquired inhibitors to factor VIII: C following a flare up of his systemic lupus erythematosus. Management issues related to recurrent bleeding in this situation are discussed and reviewed.

Role of plasmapheresis in the management of myeloma kidney: a systematic review.

Multiple myeloma complicated by acute renal failure is a diagnosis often encountered by the practicing nephrologist. The role of plasmapheresis in such patients has been of interest for decades. Three randomized controlled trials (RCTs) and multiple observational trials have evaluated the potential role of plasmapheresis in the management of this condition. This systematic review presents the results of these trials regarding survival benefits, recovery from dialysis, and improvement in renal function. A comprehensive search revealed 56 articles. Of these, only 8 articles met our inclusion criteria (3 RCTs, 1 correction of results, and 4 observational trials). Two of the 3 RCTs showed no difference in survival benefit. Two of the 3 RCTs showed a greater percentage of patients stopping dialysis in the intervention group; however, these results were not reproduced in the largest trial. All the studies showed an improvement in renal function for patients receiving plasmapheresis; however, only 2 RCTs and 1 retrospective study showed a statistically significant improvement in renal function among patients who received plasmapheresis in comparison with a control group. Our systematic review does not suggest a benefit of plasmapheresis independent of chemotherapy for multiple myeloma patients with acute renal failure in terms of overall survival, recovery from dialysis, or improvement in renal function.

The emerging role of biomarkers in diabetic and hypertensive chronic kidney disease.

Currently used measures to assess kidney function and injury are largely inadequate. Markers such as serum creatinine, formulas to estimate glomerular filtration rate, cystatin C, and proteinuria largely identify an underlying disease process that is well established. Thus, there has been a recent effort to identify new biomarkers that reflect kidney function, early injury, and/or repair that ultimately can relate to progression or regression of damage. Several biomarkers emerged recently that are able to detect kidney damage earlier than is currently possible with traditional biomarkers such as serum creatinine and proteinuria. Identification of urine biomarkers has proven to be beneficial in recent years because of ease of handling, stability, and the ability to standardize the various markers to creatinine or other peptides generally already present in the urine. Recent markers such as neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), and podocin have garnered a lot of attention. The emergence of these and other biomarkers is largely because of the evolution of novel genomic and proteomic applications in investigations of acute kidney injury and chronic kidney disease. In this article, we focus on the applications of these biomarkers in disease.

Warfarin-induced skin necrosis.

There is a lack of guidelines regarding the selection of patients who need intravenous heparin, duration of intravenous heparin, and future use of warfarin in prevention and treatment of warfarin-induced skin necrosis. This case report emphasizes the challenges in dealing with vitamin K antagonists (VKA) therapy.

Continuous ambulatory peritoneal dialysis in a patient with isolated right heart failure and ascites: a case report.

Peritoneal dialysis is the ultrafiltration therapy of choice for the long-term ambulatory management of patients with diuretic-resistant refractory congestive heart failure. Here we report a case of patient with right heart failure, massive ascites, and refractory to medical treatment treated with continuous ambulatory peritoneal dialysis.