Optimal use of SGLT2 inhibitors in diabetic kidney transplant recipients.

Sodium-glucose cotransporter 2 inhibitor (SGLT2i), a glucosuric agent initially approved for use as an antidiabetic agent, was unexpectedly found to confer cardio-and reno-protective effects in individuals with or without type 2 diabetes mellitus. Despite mounting evidence suggesting that SGLT2i provides cardio- and reno-protective benefits in both diabetic and non-diabetic and in chronic kidney disease (CKD) patients in the general population, reservations for its use in the transplant setting persist due to concerns for increased risk of genital mycotic and urinary tract infections. A comprehensive review of the literature on the efficacy and safety of SGLT2i use in diabetic kidney transplant recipients is herein presented followed by authors' opinion on its optimal use in this patient population.

Severe Hyperphosphatemia in a Patient with Mild Acute Kidney Injury.

Hyperphosphatemia may arise from various conditions including exogenous ingestion, extracellular shifts due to cell death or alterations in acid-base status, increased bone resorption, hormonal dysregulations leading to reduced renal excretion, reduced kidney function, or faulty measurement techniques. We herein present a case of a young pregnant woman who presented with mild acute kidney injury (AKI), invasive mucormycosis receiving liposomal amphotericin, and hyperphosphatemia out of proportion to the degree of kidney injury. While the patient was given routine phosphate-binding agent by her primary care team for presumed AKI-associated hyperphosphatemia, a full investigation by the renal consulting team for contributing factors other than kidney injury revealed that she actually had pseudohyperphosphatemia associated with the use of liposomal amphotericin. Erroneous treatment of pseudohyperphosphatemia may have been detrimental to this pregnant patient. A literature review for conditions associated with pseudohyperphosphatemia other than the use of liposomal amphotericin will be discussed.

Development of the phenylpyrazolo[3,4-d]pyrimidine-based, insulin-like growth factor receptor/Src/AXL-targeting small molecule kinase inhibitor.

Rationale: The type I insulin-like growth factor receptor (IGF-1R) signaling pathway plays key roles in the development and progression of numerous types of human cancers, and Src and AXL have been found to confer resistance to anti-IGF-1R therapies. Hence, co-targeting Src and AXL may be an effective strategy to overcome resistance to anti-IGF-1R therapies. However, pharmacologic targeting of these three kinases may result in enhanced toxicity. Therefore, the development of novel multitarget anticancer drugs that block IGF-1R, Src, and AXL is urgently needed. Methods: We synthesized a series of phenylpyrazolo[3,4-d]pyrimidine (PP)-based compounds, wherein the PP module was conjugated with 2,4-bis-arylamino-1,3-pyrimidines (I2) via a copper(I)-catalyzed alkyne-azide cycloaddition reaction. To develop IGF-1R/Src/AXL-targeting small molecule kinase inhibitors, we selected LL6 as an active compound and evaluated its antitumor and antimetastatic effects in vitro and in vivo using the MTT assay, colony formation assays, migration assay, flow cytometric analysis, a tumor xenograft model, the KrasG12D/+ -driven spontaneous lung tumorigenesis model, and a spontaneous metastasis model using Lewis lung carcinoma (LLC) allografts. We also determined the toxicity of LL6 in vitro and in vivo. Results: LL6 induced apoptosis and suppressed viability and colony-forming capacities of various non-small cell lung cancer (NSCLC) cell lines and their sublines with drug resistance. LL6 also suppressed the migration of NSCLC cells at nontoxic doses. Administration of LL6 in mice significantly suppressed the growth of NSCLC xenograft tumors and metastasis of LLC allograft tumors with outstanding toxicity profiles. Furthermore, the multiplicity, volume, and load of lung tumors in KrasG12D/+ transgenic mice were substantially reduced by the LL6 treatment. Conclusions: Our results show the potential of LL6 as a novel IGF-1R/Src/AXL-targeting small molecule kinase inhibitor, providing a new avenue for anticancer therapies.

Acute Kidney Failure in a Young African American Male.

Retroperitoneal fibrosis (RPF) is a condition characterized by chronic inflammatory and fibrotic changes in the retroperitoneum that can lead to serious complications including kidney failure, mesenteric and limb ischemia, and deep venous thrombosis among others. Affected individuals may present with nonspecific symptomology that would require a high clinical index of suspicion for prompt diagnosis. We herein discuss a case of a young African-American man with recurrent deep venous thrombosis who presents with a 4-week history of constant aching pain of abdomen and back and kidney failure. Initial noncontrast computed tomogram (CT) only revealed mild bilateral hydroureteronephrosis with inflammatory changes but without obvious mass or lymphadenopathy. At the insistence of the renal consulting team to rule out RPF, a CT-urogram was performed which revealed an infiltrative mass encasing the aorta, inferior vena cava, and common iliac vessels. Laparoscopic biopsy revealed dense fibroadipose tissue, lymphocytic aggregates, focal scattered IgG4-positive plasma cells, and fibrin deposition. Patient underwent bilateral nephrostomy placement and empirical corticosteroid therapy with resolution of kidney failure. Our case illustrates a classic presentation of RPF with relatively benign findings on noncontrast CT that could have been missed if clinicians did not keep a high index of suspicion for the condition.

Development of a 4-aminopyrazolo[3,4-d]pyrimidine-based dual IGF1R/Src inhibitor as a novel anticancer agent with minimal toxicity.

BACKGROUND: Both the type I insulin-like growth factor receptor (IGF1R) and Src pathways are associated with the development and progression of numerous types of human cancer, and Src activation confers resistance to anti-IGF1R therapies. Hence, targeting both IGF1R and Src concurrently is one of the main challenges in combating resistance to the currently available anti-IGF1R-based anticancer therapies. However, the enhanced toxicity from this combinatorial treatment could be one of the main hurdles for this strategy, suggesting the necessity of developing a novel strategy for co-targeting IGF1R and Src to meet an urgent clinical need. METHODS: We synthesized a series of 4-aminopyrazolo[3,4-d]pyrimidine-based dual IGF1R/Src inhibitors, selected LL28 as an active compound and evaluated its potential antitumor effects in vitro and in vivo using the MTT assay, colony formation assays, flow cytometric analysis, a tumor xenograft model, and the Kras G12D/+ -driven spontaneous lung tumorigenesis model. RESULTS: LL28 markedly suppressed the activation of IGF1R and Src and significantly inhibited the viability of several NSCLC cell lines in vitro by inducing apoptosis. Administration of mice with LL28 significantly suppressed the growth of H1299 NSCLC xenograft tumors without overt toxicity and substantially reduced the multiplicity, volume, and load of lung tumors in the Kras G12D/+ -driven lung tumorigenesis model. CONCLUSIONS: The present results suggest the potential of LL28 as a novel anticancer drug candidate targeting both IGF1R and Src, providing a new avenue to efficient anticancer therapies. Further investigation is warranted in advanced preclinical and clinical settings.

2017 update on pain management in patients with chronic kidney disease.

The prevalence of pain has been reported to be >60-70% among patients with advanced and end-stage kidney disease. Although the underlying etiologies of pain may vary, pain per se has been linked to lower quality of life and depression. The latter is of great concern given its known association with reduced survival among patients with end-stage kidney disease. We herein discuss and update the management of pain in patients with chronic kidney disease with and without requirement for renal replacement therapy with the focus on optimizing pain control while minimizing therapy-induced complications.

Cisplatin-Induced Renal Salt Wasting Requiring over 12 Liters of 3% Saline Replacement.

Cisplatin is known to induce Fanconi syndrome and renal salt wasting (RSW). RSW typically only requires transient normal saline (NS) support. We report a severe RSW case that required 12 liters of 3% saline. A 57-year-old woman with limited stage small cell cancer was admitted for cisplatin (80 mg/m2) and etoposide (100 mg/m2) therapy. Patient's serum sodium (SNa) decreased from 138 to 133 and 125 mEq/L within 24 and 48 hours of cisplatin therapy, respectively. A diagnosis of syndrome of inappropriate antidiuretic hormone secretion (SIADH) was initially made. Despite free water restriction, patient's SNa continued to decrease in association with acute onset of headaches, nausea, and dizziness. Three percent saline (3%S) infusion with rates up to 1400 mL/day was required to correct and maintain SNa at 135 mEq/L. Studies to evaluate Fanconi syndrome revealed hypophosphatemia and glucosuria in the absence of serum hyperglycemia. The natriuresis slowed down by 2.5 weeks, but 3%S support was continued for a total volume of 12 liters over 3.5 weeks. Attempts of questionable benefits to slow down glomerular filtration included the administration of ibuprofen and benazepril. To our knowledge, this is the most severe case of RSW ever reported with cisplatin.

Multiple Electrolyte and Metabolic Emergencies in a Single Patient.

While some electrolyte disturbances are immediately life-threatening and must be emergently treated, others may be delayed without immediate adverse consequences. We discuss a patient with alcoholism and diabetes mellitus type 2 who presented with volume depletion and multiple life-threatening electrolyte and metabolic derangements including severe hyponatremia (serum sodium concentration [SNa] 107 mEq/L), hypophosphatemia ("undetectable," <1.0 mg/dL), and hypokalemia (2.2 mEq/L), moderate diabetic ketoacidosis ([DKA], pH 7.21, serum anion gap [SAG] 37) and hypocalcemia (ionized calcium 4.0 mg/dL), mild hypomagnesemia (1.6 mg/dL), and electrocardiogram with prolonged QTc. Following two liters of normal saline and associated increase in SNa by 4 mEq/L and serum osmolality by 2.4 mosm/Kg, renal service was consulted. We were challenged with minimizing the correction of SNa (or effective serum osmolality) to avoid the osmotic demyelinating syndrome while replacing volume, potassium, phosphorus, calcium, and magnesium and concurrently treating DKA. Our management plan was further complicated by an episode of significant aquaresis. A stepwise approach was strategized to prioritize and correct all disturbances with considerations that the treatment of one condition could affect or directly worsen another. The current case demonstrates that a thorough understanding of electrolyte physiology is required in managing complex electrolyte disturbances to avoid disastrous outcomes.

Novel C6-substituted 1,3,4-oxadiazinones as potential anti-cancer agents.

The insulin-like growth factor 1 receptor (IGF-1R) is a membrane receptor tyrosine kinase over-expressed in a number of tumors. However, combating resistance is one of the main challenges in the currently available IGF-1R inhibitor-based cancer therapies. Increased Src activation has been reported to confer resistance to anti-IGF-1R therapeutics in various tumor cells. An urgent unmet need for IGF-1R inhibitors is to suppress Src rephosphorylation induced by current anti-IGF-1R regimens. In efforts to develop effective anticancer agents targeting the IGF-1R signaling pathway, we explored 2-aryl-1,3,4-oxadiazin-5-ones as a novel scaffold that is structurally unrelated to current tyrosine kinase inhibitors (TKIs). The compound, LL-2003, exhibited promising antitumor effects in vitro and in vivo; it effectively suppressed IGF-1R and Src and induced apoptosis in various non-small cell lung cancer cells. Further optimizations for enhanced potency in cellular assays need to be followed, but our strategy to identify novel IGF-1R/Src inhibitors may open a new avenue to develop more efficient anticancer agents.

Management of patients with a failed kidney transplant: Dialysis reinitiation, immunosuppression weaning, and transplantectomy.

The number of patients reinitiating dialysis after a failed transplant increases over time and has more than doubled between the year 1988 and 2010 (an increase from 2463 to 5588). More importantly, patients returning to dialysis have been shown to have a greater than three-fold increase in the annual adjusted mortality rates compared with those with a functioning graft. Continuation of immunosuppression to preserve residual graft function has been implicated to be a contributing factor, seemingly due to immunosuppression-associated cardiovascular and infectious complications and malignancy risk, among others. Nonetheless, maintenance low-dose immunosuppression has been suggested to confer survival benefit in patients returning to peritoneal dialysis. Whether early vs late reinitiation of dialysis or whether transplantectomy has an impact on patient survival remains poorly defined. Consensus guidelines for the management of a failed allograft are lacking. In this article, we present a literature overview on the ideal timing of dialysis reinitiation after graft loss, the management of immunosuppression after graft failure, and the risks and benefits of transplantectomy. The authors' perspectives on the management of this special patient population are also discussed.

Correction of hyponatremia and osmotic demyelinating syndrome: have we neglected to think intracellularly?

BACKGROUND: Osmotic demyelination syndrome (ODS) is a complication generally associated with overly rapid correction of hyponatremia. Traditionally, nephrologists have been trained to focus solely on limiting the correction rate. However, there is accumulating evidence to suggest that the prevention of ODS is beyond achieving slow correction rates. METHODS: We (1) reviewed the literature for glial intracellular protective alterations during hyperosmolar stress, a state presumed equivalent to the rapid correction of hyponatremia, and (2) analyzed all available hyponatremia-associated ODS cases from PubMed for possible contributing factors including correction rates and concurrent metabolic disturbances involving hypokalemia, hypophosphatemia, hypomagnesemia, and/or hypoglycemia. RESULTS: In response to acute hyperosmolar stress, glial cells undergo immediate extracellular free water shift, followed by active intracellular Na(+), K(+) and amino acid uptake, and eventual idiogenic osmoles synthesis. At minimum, protective mechanisms require K(+), Mg(2+), phosphate, amino acids, and glucose. There were 158 cases of hyponatremia-associated ODS where both correction rates and other metabolic factors were documented. Compared with the rapid correction group (>0.5 mmol/L/h), the slow correction group (≤0.5 mmol/L/h) had a greater number of cases with concurrent hypokalemia (49.4 vs. 33.3 %, p = 0.04), and a greater number of cases with any concurrent metabolic derangements (55.8 vs. 38.3 %, p = 0.03). CONCLUSION: Glial cell minimizes volume changes and injury in response to hyperosmolar stress via mobilization and/or utilization of various electrolytes and metabolic factors. The prevention of ODS likely requires both minimization of correction rate and optimization of intracellular response during the correction phase when a sufficient supply of various factors is necessary.

BK virus infection following kidney transplantation: an overview of risk factors, screening strategies, and therapeutic interventions.

PURPOSE OF REVIEW: In recipients of kidney transplants, the emergence of BK virus (BKV)-associated clinical syndromes, such as viruria, viremia, and BK nephropathy, coincided with the advent of potent immunosuppressive therapy. There is currently no standardized protocol for the management of BK viruria or viremia, or established BK nephropathy. Suggested risk factors for BKV replication and a literature overview on various treatment strategies for BKV-associated clinical syndromes are presented, followed by the authors' proposed approach for screening, monitoring, and treatment of post-transplant BKV infection. RECENT FINDINGS: BKV infection can occur under all combinations of immunosuppressive therapy. Although both humoral and cellular immunity may be essential, BKV-specific T-cell immunity appears to play a pivotal role in controlling BKV replication. Monitoring BKV-specific immune response might prove useful in guiding therapeutic intervention. The beneficial effects of antiviral agents remain unclear. Development of T-cell or antibody-based vaccines against BKV is a subject of future research. SUMMARY: In the absence of conclusive evidence that any particular immunosuppressive agent has a specific influence over another on BKV infection risk and the unclear benefit of antiviral agents, intensive monitoring of serum BKV using PCR and immunological containment of BKV replication should remain the mainstay of therapy. The routine recommendations of antiviral agents in the treatment of BKV-associated clinical syndromes await results of large prospective randomized trials.

Hypomagnesemia: a clinical perspective.

Although magnesium is involved in a wide spectrum of vital functions in normal human physiology, the significance of hypomagnesemia and necessity for its treatment are under-recognized and underappreciated in clinical practice. In the current review, we first present an overview of the clinical significance of hypomagnesemia and normal magnesium metabolism, with a focus on renal magnesium handling. Subsequently, we review the literature for both congenital and acquired hypomagnesemic conditions that affect the various steps in normal magnesium metabolism. Finally, we present an approach to the routine evaluation and suggested management of hypomagnesemia.

Membranoproliferative glomerulonephritis in patients with chronic venous catheters: a case report and literature review.

Chronic indwelling catheters have been reported to be associated with membranoproliferative glomerulonephritis (MPGN) via the activation of the classical complement pathway in association with bacterial infections such as coagulase negative staphylococcus. We herein provide supporting evidence for the direct causal relationship between chronic catheter infections and MPGN via a case of recurrent MPGN associated with recurrent catheter infections used for total parenteral nutrition (TPN) in a man with short gut syndrome. We also present a literature review of similar cases and identify common clinical manifestations that may serve to aid clinicians in the early identification of MPGN associated with infected central venous catheterization or vice versa. The importance of routine monitoring of kidney function and urinalysis among patients with chronic central venous catheterization is highlighted as kidney injury may herald or coincide with overtly infected chronic indwelling central venous catheters.

Kidney transplantation in the obese transplant candidates: to transplant or not to transplant?

The prevalence of obesity (body mass index ≥30 kg/m(2)) at the time of transplantation among kidney transplant recipients in the United States has doubled between 1987 and 2001 and continues to increase inexorably. Single-center and large registry studies in kidney transplant recipients demonstrated that high body mass index (BMI) at transplant is associated with increased risk of wound and surgical site infections, delayed graft function (DGF), acute rejection episodes, and graft loss, among others. Hence, in many centers, obese transplant candidates are denied a transplant based on their body mass index (BMI) alone. The impact of obesity on short- and long-term graft and patient outcomes after kidney transplantation are herein revisited, followed by the authors' proposed approach to evaluate and select obese transplant candidates for a kidney transplant. Suggested interventions to optimize the health of such candidates are also discussed.

Screening strategies and predictive diagnostic tools for the development of new-onset diabetes mellitus after transplantation: an overview.

New-onset diabetes mellitus after transplantation (NODAT) is a serious and common complication following solid organ transplantation. NODAT has been reported in 2% to 53% of all solid organ transplants. Kidney transplant recipients who develop NODAT have variably been reported to be at increased risk of fatal and nonfatal cardiovascular events and other adverse outcomes including infection, reduced patient survival, graft rejection, and accelerated graft loss compared with those who do not develop diabetes. Limited clinical studies in liver, heart, and lung transplants similarly suggested that NODAT has an adverse impact on patient and graft outcomes. Early detection and management of NODAT must, therefore, be integrated into the treatment of transplant recipients. Studies investigating the best screening or predictive tool for identifying patients at risk for developing NODAT early after transplantation, however, are lacking. We review the clinical predictive values of fasting plasma glucose, oral glucose tolerance test, and A1C in assessing the risk for NODAT development and as a screening tool. Simple diabetes prediction models that incorporate clinical and/or metabolic risk factors (such as age, body mass index, hypertriglyceridemia, or metabolic syndrome) are also presented.