Palopegteriparatide Treatment Improves Renal Function in Adults with Chronic Hypoparathyroidism: 1-Year Results from the Phase 3 PaTHway Trial.

INTRODUCTION: Individuals with chronic hypoparathyroidism managed with conventional therapy (active vitamin D and calcium) have an increased risk for renal dysfunction versus age- and sex-matched controls. Treatments that replace the physiologic effects of parathyroid hormone (PTH) while reducing the need for conventional therapy may help prevent a decline in renal function in this population. This post hoc analysis examined the impact of palopegteriparatide treatment on renal function in adults with chronic hypoparathyroidism. METHODS: PaTHway is a phase 3 trial of palopegteriparatide in adults with chronic hypoparathyroidism that included a randomized, double-blind, placebo-controlled 26-week period followed by an ongoing 156-week open-label extension (OLE) period. Changes in renal function over 52 weeks (26 weeks blinded + 26 weeks OLE) were assessed using estimated glomerular filtration rate (eGFR). A subgroup analysis was performed with participants stratified by baseline eGFR < 60 or ≥ 60 mL/min/1.73 m2. RESULTS: At week 52, over 95% (78/82) of participants remained enrolled in the OLE and of those, 86% maintained normocalcemia and 95% achieved independence from conventional therapy (no active vitamin D and ≤ 600 mg/day of calcium), with none requiring active vitamin D. Treatment with palopegteriparatide over 52 weeks resulted in a mean (SD) increase in eGFR of 9.3 (11.7) mL/min/1.73 m2 from baseline (P < 0.0001) and 43% of participants had an increase ≥ 10 mL/min/1.73 m2. In participants with baseline eGFR < 60 mL/min/1.73 m2, 52 weeks of treatment with palopegteriparatide resulted in a mean (SD) increase of 11.5 (11.3) mL/min/1.73 m2 (P < 0.001). One case of nephrolithiasis was reported for a participant in the placebo group during blinded treatment; none were reported through week 52 with palopegteriparatide. CONCLUSION: In this post hoc analysis of the PaTHway trial, palopegteriparatide treatment was associated with significantly improved eGFR at week 52 in addition to previously reported maintenance and normalization of serum and urine biochemistries. Further investigation of palopegteriparatide for the preservation of renal function in hypoparathyroidism is warranted. TRIAL REGISTRATION: ClinicalTrials.gov NCT04701203.

Chronic hypoparathyroidism is caused by inadequate parathyroid hormone (PTH) levels. Hypoparathyroidism is managed with conventional therapy (active vitamin D and calcium), but over time the disease itself and conventional therapy can increase the risk of medical complications including kidney problems. This study looked at how a new treatment for chronic hypoparathyroidism, palopegteriparatide (approved in the European Union under the brand name YORVIPATH^®), affects kidney function in adults in the PaTHway clinical trial. Participants were randomly assigned to receive palopegteriparatide or a placebo injection once daily along with conventional therapy. For both groups, clinicians used a protocol to eliminate conventional therapy while maintaining normal blood calcium levels. After 26 weeks, participants on placebo switched to palopegteriparatide. Ninety-five percent of participants were still enrolled in the PaTHway trial after 52 weeks. Of those, 86% had normal blood calcium levels and 95% did not need conventional therapy (not taking vitamin D and not taking therapeutic doses of calcium [> 600 mg/day]). After 52 weeks of treatment with palopegteriparatide, significant improvements were seen in a measure of kidney function called estimated glomerular filtration rate (eGFR). Improvements in eGFR from the beginning of the trial to week 52 were considered clinically meaningful for over 57% of participants. In participants with impaired kidney function at the beginning of the trial, eGFR improvements were even greater, and 74% of participants had a clinically meaningful improvement. These results suggest that palopegteriparatide treatment may be beneficial for kidney function in adults with chronic hypoparathyroidism, especially those with impaired kidney function.

Five-Year Estimated Glomerular Filtration Rate in Adults with Chronic Hypoparathyroidism Treated with rhPTH(1-84): A Retrospective Cohort Study.

INTRODUCTION: Chronic hypoparathyroidism is associated with higher risk of developing chronic kidney disease compared with the general population. This study evaluated changes in estimated glomerular filtration rate (eGFR) over a 5-year period in adult patients with chronic hypoparathyroidism treated with recombinant parathyroid hormone (1-84), rhPTH(1-84), compared with a historical control cohort of patients who did not receive rhPTH(1-84). METHODS: This retrospective cohort study included patients with chronic hypoparathyroidism treated with rhPTH(1-84) in the REPLACE (NCT00732615), RELAY (NCT01268098), RACE (NCT01297309), and HEXT (NCT01199614 and continuation study NCT02910466) clinical trials. A historical control cohort who did not receive parathyroid hormone but who had enrollment criteria similar to those for the clinical trials was selected from the IBM® Explorys electronic medical record database (January 2007-August 2019). Outcomes of interest were the annual rate of change in eGFR from baseline (i.e., eGFR slope) and the predicted eGFR change from baseline at years 1 through 5. RESULTS: The study comprised 72 adult patients with chronic hypoparathyroidism treated with rhPTH(1-84) and 176 control patients who did not receive rhPTH(1-84). Over 5 years, eGFR remained stable in the rhPTH(1-84) cohort, whereas eGFR declined at a rate of 1.67 mL/min/1.73 m2 per year in the control cohort (P < 0.001 for eGFR slope in the control cohort). At 5 years, predicted eGFR in the rhPTH(1-84) cohort increased from baseline by 1.21 mL/min/1.73 m2, whereas eGFR in the control cohort declined by 10.36 mL/min/1.73 m2, after adjusting for baseline variables. The difference in eGFR slopes between the cohorts over 5 years was 1.37 mL/min/1.73 m2 per year (95% CI 0.62-2.13; P < 0.001). CONCLUSION: Long-term treatment with rhPTH(1-84) was associated with stable eGFR compared with eGFR decline in the controls not treated with rhPTH(1-84). Preservation of renal function conferred by rhPTH(1-84) may benefit patients with chronic hypoparathyroidism by reducing risk of long-term renal complications.

Serum Low-Density Lipoprotein Cholesterol and Cardiovascular Disease Risk Across Chronic Kidney Disease Stages (Data from 1.9 Million United States Veterans).

In the general population, elevated low-density lipoprotein (LDL) cholesterol levels are an important risk factor for cardiovascular disease (CVD) and mortality; however, the association of LDL with mortality risk and cardiovascular events are less clear in chronic kidney disease (CKD). We sought to examine the relationship of LDL with mortality and rates of atherosclerotic cardiovascular disease (ASCVD) and non-atherosclerotic cardiovascular-related (non-ASCVD) hospitalizations across CKD stages. Our analytical cohort consisted of 1,972,851 United States veterans with serum LDL data between 2004 and 2006. Associations of LDL with all-cause and cardiovascular mortality across CKD stages were evaluated using Cox proportional hazard models with adjustment for demographics, comorbid conditions, smoking status, prescription of statins and non-statin lipid-lowering drugs, body mass index, albumin, high-density lipoprotein, and triglycerides. Associations between LDL and ASCVD and non-ASCVD hospitalizations were estimated using negative binomial regression models across CKD stages. The cohort consisted of 5% female, 14% Black, 29% diabetic, 33% statin-users, and 44% current smokers, with a mean patient age of 64 ± 14 years. Patients with high LDL (≥160 mg/dL) had a higher risk of all-cause and cardiovascular mortality as well as ASCVD and non-ASCVD hospitalization rates across all CKD stages compared with the reference (LDL 70 to <100 mg/dL). The associations with all-cause and cardiovascular mortality and ASCVD hospitalization rate were attenuated at higher CKD stages. These trends were reversed with amplification of the association of high LDL with non-ASCVD hospitalization at higher CKD stages. In conclusion, associations of LDL with mortality and both ASCVD and non-ASCVD hospitalizations are modified according to kidney disease stage.

Risk of Chronic Kidney Disease and Estimated Glomerular Filtration Rate Decline in Patients with Chronic Hypoparathyroidism: A Retrospective Cohort Study.

INTRODUCTION: Chronic hypoparathyroidism, treated with conventional therapy of oral calcium supplements and active vitamin D, may increase the risk of kidney complications. This study examined risks of development and progression of chronic kidney disease (CKD) and estimated glomerular filtration rate (eGFR) decline in patients with chronic hypoparathyroidism. METHODS: A retrospective cohort study using a managed care claims database in the United States from January 2007 to June 2017 included patients with chronic hypoparathyroidism (excluding those receiving parathyroid hormone) and randomly selected patients without hypoparathyroidism followed for up to 5 years. Main outcome measures were (1) development of CKD, defined as new diagnosis of CKD stage 3 and higher or ≥ 2 eGFR measurements < 60 ml/min/1.73 m2 ≥ 3 months apart, (2) progression of CKD, defined as increase in baseline CKD stage, (3) progression to end-stage kidney disease (ESKD), and (4) eGFR decline ≥ 30% from baseline. Time-to-event analyses included Kaplan-Meier analyses with log-rank tests, and both unadjusted and adjusted Cox proportional hazards models were used to compare outcomes between cohorts. RESULTS: The study included 8097 adults with and 40,485 without chronic hypoparathyroidism. In Kaplan-Meier analyses, patients with chronic hypoparathyroidism had higher risk of developing CKD and CKD progression and higher rates of eGFR decline (all P < 0.001). In multivariable Cox models adjusted for baseline characteristics, hazard ratios (95% confidence intervals [CIs]) were 2.91 (2.61-3.25) for developing CKD, 1.58 (1.23-2.01) for CKD stage progression, 2.14 (1.51-3.04) for progression to ESKD, and 2.56 (1.62-4.03) for eGFR decline (all P < 0.001) among patients with chronic hypoparathyroidism compared with those without hypoparathyroidism. CONCLUSION: Patients with chronic hypoparathyroidism have increased risk of development and progression of CKD and eGFR decline compared with those without hypoparathyroidism. Further studies are warranted to understand underlying mechanisms for the associations between chronic hypoparathyroidism and kidney disease.

Systemic Bartonellosis Manifesting With Endocarditis and Membranoproliferative Glomerulonephritis.

Cat scratch disease caused by Bartonella species is mostly benign and self-limiting condition. Systemic infection is uncommon in immunocompetent host. We describe the case of a 66-year-old male who presented with sudden painless left eye blindness and brown-colored urine. Laboratory findings revealed progressively rising serum creatinine in association with nephrotic-range proteinuria at 7 g/day and glomerular hematuria on urinalysis. An echocardiogram demonstrated mitral and tricuspid valve vegetations despite multiple negative blood cultures. The left eye blindness was attributed to retinal artery occlusion from septic valvular embolus. Kidney biopsy showed membranoproliferative glomerulonephritis pattern of injury with "full house" pattern on immunofluorescent staining with subendothelial deposits on electron microscopy. Markedly elevated IgG (immunoglobulin G) titers for B henselae and B quintana were discovered. The patient had several cats at home. Kidney failure rapidly progressed to require hemodialysis. Once the diagnosis of systemic bartonellosis was confirmed, doxycycline (for 4 months) with rifampicin (for 3 months) were initiated. Repeat echocardiogram in 4 months demonstrated a resolution of valvular vegetations; however, the left eye blindness was permanent. In the present case the correct diagnosis of systemic bartonellosis allowed institution of appropriate antibiotic therapy and to also achieve a partial recovery of renal function and to discontinue hemodialysis.

Attainment of Guideline-Directed Medical Treatment in Stable Ischemic Heart Disease Patients With and Without Chronic Kidney Disease.

BACKGROUND: Stable ischemic heart disease (SIHD) is prevalent in patients with chronic kidney disease (CKD); however, whether guideline-directed medical therapy (GDMT) is adequately implemented in patients with SIHD and CKD is unknown. HYPOTHESIS: Use of GDMT and achievement of treatment targets would be higher in SIHD patients without CKD than in patients with CKD. METHODS: This was a retrospective study of 563 consecutive patients with SIHD (mean age 67.8 years, 84% Caucasians, 40% females). CKD was defined as an estimated glomerular filtration rate (eGFR) of < 60 mL/min/1.73m2 using the four-variable MDRD Study equation. We examined the likelihood of achieving GDMT targets (prescription of high-intensity statins, antiplatelet agents, renin-angiotensin-aldosterone system inhibitors (RAASi), and low-density lipoprotein cholesterol levels < 70 mg/dL, blood pressure < 140/90 mmHg, and hemoglobin A1C < 7% if diabetes) in patients with (n = 166) and without CKD (n = 397). RESULTS: Compared with the non-CKD group, CKD patients were significantly older (72 vs 66 years; p < 0.001), more commonly female (49 vs 36%; p = 0.002), had a higher prevalence of diabetes (46 vs 34%; p = 0.004), and left ventricular systolic ejection fraction (LVEF) < 40% (23 vs. 10%, p < 0.001). All GDMT goals were achieved in 26% and 24% of patients with and without CKD, respectively (p = 0.712). There were no between-group differences in achieving individual GDMT goals with the exception of RAASi (CKD vs non-CKD: adjusted risk ratio 0.73, 95% CI 0.62-0.87; p < 0.001). CONCLUSIONS: Attainment of GDMT goals in SIHD patients with CKD was similar to patients without CKD, with the exception of lower rates of RAASi use in the CKD group.

A Case Report of Rash at Peritoneal Dialysis Exit Site.

The International Society for Peritoneal Dialysis recommends the regular application of topical antibiotic-containing preparations in addition to a routine exit site care to reduce the risk of exit site infection (ESI). Among these prophylactic antimicrobial preparations, topical gentamicin is one of the widely used and effective antibiotics for prevention of ESI and peritonitis in peritoneal dialysis (PD) patients. Overall, topical gentamicin is well tolerated; however, its use can be associated with the development of allergic contact dermatitis (ACD). We describe a first reported case of PD catheter exit site contact ACD due to topical gentamicin mimicking ESI. The patient in this report developed worsening violaceous in color and pruritic rash surrounding the PD catheter exit site that appeared 3 weeks after the initiation of gentamicin cream. The association between development of rash and initiation of topical gentamicin led to a suspicion of local reaction to gentamicin rather than ESI. Skin biopsy confirmed ACD. Discontinuation of the provoking agent and subsequent treatment with topical hydrocortisone application led to a resolution of the exit site rash. Any rash at a PD catheter exit site should be considered infectious until proven otherwise. However, it is important to be aware of noninfectious etiologies of exit site rashes as the treatment of these 2 conditions differs.

Application of ultrasound in nephrology practice.

Ultrasonography plays critical roles in many aspects of nephrology practice. Applications include the evaluation of the kidneys and urinary tract, guidance for the percutaneous kidney biopsy and temporary hemodialysis access placement, and vascular ultrasound of upper extremities related to the permanent hemodialysis access. The simplicity of technique and the limited spectrum of pathological changes coupled with portability, low cost, and safety make sonography the modality of choice for kidney and vascular imaging. This review summarizes the indications for kidney and vascular ultrasound and describes the most commonly encountered findings. Although many ultrasound findings are nonspecific, their diagnostic use is greatly enhanced by knowledge of the clinical presentation. Therefore, it is essential for nephrologists to possess skills in performing and interpreting ultrasound studies in order to improve the care of patients with kidney diseases.