Acquired multiple acyl-CoA dehydrogenase deficiency and marked selenium deficiency causing severe rhabdomyolysis in a horse.

This report describes a case of severe rhabdomyolysis in a pregnant mare associated with histopathologic and biochemical features of both selenium deficiency and acquired multiple acyl-CoA dehydrogenase deficiency (MADD) due to seasonal pasture myopathy (SPM). This case highlights the importance of assessing plasma selenium levels in horses with clinical signs of pasture myopathy as this deficiency may be a contributing or exacerbating factor.

Déficience multiple acquise de déshydrogénase acyl-CoA et carence en sélénium marquée causant une rhabdomyolyse grave chez un cheval. Ce rapport décrit le cas d'une rhabdomyolyse grave chez une jument gravide associée à des caractéristiques histopathologiques et biochimiques de la carence en sélénium et d'une carence multiple acquise de déhydrogénase acyl-CoA (MADD) causées par la myopathie saisonnière des pâturages (SPM). Ce cas souligne l'importance d'évaluer les niveaux de sélénium dans le plasma des chevaux manifestant des signes cliniques de myopathie du pâturage car cette carence peut être un facteur contributif ou aggravant.(Traduit par Isabelle Vallières).

Sarcopenia, adiposity and large discordance between cystatin C and creatinine-based estimated glomerular filtration rate in patients with cancer.

BACKGROUND: Creatinine-based estimated glomerular filtration rate (eGFRCRE) may overestimate kidney function in patients with sarcopenia. While cystatin C-based eGFR (eGFRCYS) is less affected by muscle mass, it may underestimate kidney function in patients with obesity. We sought to evaluate the relationship between body composition defined by computed tomography (CT) scans and discordance between creatinine, eGFRCRE and eGFRCYS in adult patients with cancer. METHODS: This study is a cross-sectional study of consecutive adults with cancer with an abdominal CT scan performed within 90 days of simultaneous eGFRCRE and eGFRCYS measurements between May 2010 and January 2022. Muscle and adipose tissue cross-sectional areas were measured at the level of the third lumbar vertebral body using a validated deep-learning pipeline. CT-defined sarcopenia was defined using independent sex-specific cut-offs for skeletal muscle index (<39 cm2/m2 for women and <55 cm2/m2 for men). High adiposity was defined as the highest sex-specific quartile of the total (visceral plus subcutaneous) adiposity index in the cohort. The primary outcome was eGFR discordance, defined by eGFRCYS > 30% lower than eGFRCRE; the secondary outcome was eGFRCYS > 50% lower than eGFRCRE. The odds of eGFR discordance were estimated using multivariable logistic regression modelling. Unadjusted spline regression was used to evaluate the relationship between skeletal muscle index and the difference between eGFRCYS and eGFRCRE. RESULTS: Of the 545 included patients (mean age 63 ± 14 years, 300 [55%] females, 440 [80.7%] non-Hispanic white), 320 (58.7%) met the criteria for CT-defined sarcopenia, and 136 (25%) had high adiposity. A total of 259 patients (48%) had >30% eGFR discordance, and 122 (22.4%) had >50% eGFR discordance. After adjustment for potential confounders, CT-defined sarcopenia and high adiposity were both associated with >30% eGFR discordance (adjusted odds ratio [aOR] 1.90, 95% confidence interval [CI] 1.12-3.24; aOR 2.01, 95% CI 1.15-3.52, respectively) and >50% eGFR discordance (aOR 2.34, 95% CI 1.21-4.51; aOR 2.23, 95% CI 1.19-4.17, respectively). A spline model demonstrated that as skeletal muscle index decreases, the predicted difference between eGFRCRE and eGFRCYS widens considerably. CONCLUSIONS: CT-defined sarcopenia and high adiposity are both independently associated with large eGFR discordance. Incorporating valuable information from body composition analysis derived from CT scans performed as a part of routine cancer care can impact the interpretation of GFR estimates.

Medication-related adverse events in patients with cancer and discrepancies in cystatin C- versus creatinine-based eGFR.

Background: Creatinine-based estimated glomerular filtration rate (eGFRCRE) may overestimate kidney function in patients with cancer. Cystatin C-based eGFR (eGFRCYS) is an alternative marker of kidney function. We investigated whether patients with an eGFR discrepancy, defined as eGFRCYS >30% lower than the concurrent eGFRCRE, had an increased risk of adverse events resulting from renally-cleared medications. Patients and Methods: We conducted a cohort study of adult patients with cancer who had serum creatinine and cystatin C measured on the same day between May 2010 and January 2022 at two academic cancer centers in Boston, MA. The primary outcome was the incidence of each of the following medication-related adverse events: 1) supratherapeutic vancomycin levels (>30µg/mL); 2) trimethoprim-sulfamethoxazole-related hyperkalemia (>5.5mEq/L); 3) baclofen-induced neurotoxicity; and 4) supratherapeutic digoxin levels (>2.0ng/mL). Results: 1988 patients with cancer had simultaneous eGFRCYS and eGFRCRE. The mean age was 66 years (SD±14), 965 (49%) were female, and 1555 (78%) were non-Hispanic white. eGFR discrepancy occurred in 579 patients (29%). Patients with eGFR discrepancy were more likely to experience medication-related adverse events compared to those without eGFR discrepancy: vancomycin levels >30µg/mL (24% vs. 10%, p=0.004), trimethoprim- sulfamethoxazole-related hyperkalemia (24% vs. 12%, p=0.013), baclofen-induced neurotoxicity (25% vs. 0%, p=0.13), and supratherapeutic digoxin levels (38% vs. 0%, p=0.03). The adjusted OR for vancomycin levels >30µg/mL was 2.30 (95% CI 1.05 - 5.51, p = 0.047). Conclusion: Among patients with cancer with simultaneous assessment of eGFRCYS and eGFRCRE, medication-related adverse events occur more commonly in those with eGFR discrepancy. These findings underscore the importance of accurate assessment of kidney function and appropriate dosing of renally-cleared medications in patients with cancer.

Adverse kidney outcomes of CDK 4/6 inhibitors for metastatic breast cancer.

Cyclin-dependent kinase (CDK) 4/6 inhibitors have significantly improved overall and progression free survival of patients with metastatic breast cancer, but their effect on short and long-term kidney function is unknown. We found that early, mild estimated glomerular filtration rate (eGFR) decline was common in patients treated with CDK 4/6 inhibitors; however, severe kidney injury is rare and long-term eGFR decline is uncommon.

Medication-Related Adverse Events and Discordancies in Cystatin C-Based vs Serum Creatinine-Based Estimated Glomerular Filtration Rate in Patients With Cancer.

Importance: Serum creatinine-based estimated glomerular filtration rate (eGFRcr) may overestimate the glomerular filtration rate (GFR) in patients with cancer. Cystatin C-based eGFR (eGFRcys) is an alternative marker of GFR. Objective: To determine whether the therapeutic drug levels and adverse events (AEs) associated with renally cleared medications were higher in patients with cancer whose eGFRcys was more than 30% lower than their eGFRcr. Design, Setting, and Participants: This cohort study analyzed adult patients with cancer at 2 major academic cancer centers in Boston, Massachusetts. These patients had their creatinine and cystatin C measured on the same day between May 2010 and January 2022. The date of the first simultaneous eGFRcr and eGFRcys measurement was considered to be the baseline date. Exposure: The primary exposure was eGFR discordance, defined as an eGFRcys that was more than 30% lower than the eGFRcr. Main Outcomes and Measures: The primary outcome was risk of the following medication-related AEs within 90 days of the baseline date: (1) supratherapeutic vancomycin trough level greater than 30 µg/mL, (2) trimethoprim-sulfamethoxazole-related hyperkalemia (>5.5 mEq/L), (3) baclofen toxic effect, and (4) supratherapeutic digoxin level (>2.0 ng/mL). For the secondary outcome, a multivariable Cox proportional hazards regression model was used to compare 30-day survival of those with vs without eGFR discordance. Results: A total of 1869 adult patients with cancer (mean [SD] age, 66 [14] years; 948 males [51%]) had simultaneous eGFRcys and eGFRcr measurement. There were 543 patients (29%) with an eGFRcys that was more than 30% lower than their eGFRcr. Patients with an eGFRcys that was more than 30% lower than their eGFRcr were more likely to experience medication-related AEs compared with patients with concordant eGFRs (defined as eGFRcys within 30% of eGFRcr), including vancomycin levels greater than 30 µg/mL (43 of 179 [24%] vs 7 of 77 [9%]; P = .01), trimethoprim-sulfamethoxazole-related hyperkalemia (29 of 129 [22%] vs 11 of 92 [12%]; P = .07), baclofen toxic effects (5 of 19 [26%] vs 0 of 11; P = .19), and supratherapeutic digoxin levels (7 of 24 [29%] vs 0 of 10; P = .08). The adjusted odds ratio for vancomycin levels more than 30 µg/mL was 2.59 (95% CI, 1.08-7.03; P = .04). Patients with an eGFRcys more than 30% lower than their eGFRcr had an increased 30-day mortality (adjusted hazard ratio, 1.98; 95% CI, 1.26-3.11; P = .003). Conclusions and relevance: Results of this study suggest that among patients with cancer with simultaneous assessment of eGFRcys and eGFRcr, supratherapeutic drug levels and medication-related AEs occurred more commonly in those with an eGFRcys more than 30% lower than their eGFRcr. Future prospective studies are needed to improve and personalize GFR estimation and medication dosing in patients with cancer.

Kidney function in patients with ovarian cancer treated with poly (ADP-ribose) polymerase (PARP) inhibitors.

BACKGROUND: Poly (ADP-ribose) polymerase inhibitors (PARPi) have revolutionized the treatment of ovarian cancer; however, real-world data on kidney function among patients treated with PARPi are lacking. METHODS: We identified adults treated with olaparib or niraparib between 2015 and 2021 at a major cancer center in Boston, MA, USA. We determined the incidence of any acute kidney injury (AKI), defined as at least a 1.5-fold rise in serum creatinine from baseline in the first 12 months following PARPi initiation. We calculated the percentage of patients with any AKI and sustained AKI and adjudicated the etiologies by manual chart review. We compared trajectories in estimated glomerular filtration rate (eGFR) among PARPi-treated and carboplatin and paclitaxel-treated patients with ovarian cancer, matched by baseline eGFR. RESULTS: Of 269 patients, 60 (22.3%) developed AKI, including 43 of 194 (22.1%) olaparib-treated patients and 17 of 75 (22.7%) niraparib-treated patients. Only 9 of 269 (3.3%) had AKI attributable to the PARPi. Of the 60 patients with AKI, 21 (35%) had sustained AKI, of whom 6 had AKI attributable to the PARPi (2.2% of the whole cohort). eGFR declined within 30 days post-PARPi initiation by 9.61 (SD = 11.017) mL/min per 1.73 m2 but recovered by 8.39 (SD = 14.05) mL/min per 1.73 m2 within 90 days after therapy cessation. There was no difference in eGFR at 12 months post-therapy initiation in patients receiving PARPi or controls receiving carboplatin and paclitaxel (P = .29). CONCLUSIONS: AKI is common following PARPi initiation as is a transient decline in eGFR; however, sustained AKI directly attributable to the PARPi and long-term eGFR decline are uncommon.

Clinical Features of Acute Kidney Injury in the Early Post-Transplantation Period Following Reduced-Intensity Conditioning Allogeneic Hematopoietic Stem Cell Transplantation.

Allogeneic hematopoietic stem cell transplantation (HCT) is a potentially curative therapy for patients with hematologic malignancies but is associated with acute kidney injury (AKI). To date, few studies have examined risk factors for AKI at engraftment, or the relationship between AKI and clinical outcomes. This study examined the incidence and risk factors for periengraftment AKI, as well as the association between AKI and overall survival (OS) and nonrelapse mortality (NRM). We conducted a retrospective analysis of adult patients undergoing reduced-intensity conditioning (RIC) allogeneic HCT at the Dana-Farber Cancer Institute between 2012 and 2019. Periengraftment (day 0 to day 30) AKI incidence and severity were defined using modified KDIGO (Kidney Disease: Improving Global Outcomes) criteria. Factors associated with periengraftment AKI risk were examined using Cox regression analysis. The impact of periengraftment AKI on OS and NRM (defined as death without recurrent disease after HCT), was evaluated using Cox regression and the Fine and Gray competing risks model, respectively. Kidney recovery, defined as a return of serum creatinine (SCr) to within 25% of baseline or liberation from kidney replacement therapy (KRT), was examined at day 90 post-HCT. Periengraftment AKI occurred in 330 of 987 patients (33.4%) at a median of 13 days (interquartile range, 4 to 30 days) post-transplantation. Factors associated with a higher multivariable-adjusted risk of AKI were supratherapeutic rapamycin (hazard ratio [HR], 1.56; 95% confidence interval [CI], 1.20 to 2.03; P < .001), fludarabine/melphalan conditioning (HR, 1.35, 95% CI, 1.01 to 1.81; P = .05, compared to fludarabine/busulfan and fludarabine, cyclophosphamide, and total body irradiation), HCT Comorbidity Index ≥4 (HR, 1.43; 95% CI, 1.14 to 1.79; P = .002), albumin <3.4 g/dL (HR, 2.04; 95% CI, 1.33 to 3.12; P = .001), hemoglobin ≤12 (HR, 1.96; 95% CI, 1.38 to 2.78; P < .001), supratherapeutic tacrolimus (HR, 1.45; 95% CI, 1.07 to 1.95; P = .02), and baseline SCr >1.1 mg/dL (HR, 1.87; 95% CI, 1.48 to 2.35; P < .001). Periengraftment AKI was associated with worse OS (HR, 1.40; 95% CI, 1.16 to 1.71; P < .001) and NRM (subdistribution HR, 2.10; 95% CI, 1.52 to 2.89; P < .001). Kidney recovery occurred in 18%, 15%, and 30% of patients with stage 1, stage 2, and stage 3 AKI without KRT, respectively, and 4 of 16 patients (25%) were liberated from KRT. Periengraftment AKI is common among RIC allogeneic HCT recipients. We identified several important risk factors for periengraftment AKI. Its association with worse OS and NRM underscores the importance of timely recognition and management.

Comparison of bacterial culture, histopathology, and immunohistochemistry for the diagnosis of Johne's disease in culled dairy cows.

Paired samples of formalin-fixed, paraffin-embedded ileum and lymph node from 204 culled dairy cows were investigated for evidence of infection by Mycobacterium avium subsp. paratuberculosis. Of the samples, 151 were from animals that were tissue-culture positive for M. avium subsp. paratuberculosis, and 53 were from animals that were tissue and fecal culture negative. From the culture-positive animals, M. avium subsp. paratuberculosis was isolated from 78 samples of ileum and from 107 samples of lymph node. Ziehl-Neelsen acid-fast and immunoperoxidase stained slides were examined for 15 minutes each. Acid-fast organisms were identified in 7 of 78 (8.97%) and 6 of 106 (5.61%) culture-positive ileum and lymph node samples, respectively. Immunohistochemical (IHC) analysis of the same tissues identified infection in the ileum of 9 of 78 (11.54%) and in the lymph node of 5 of 106 (4.67%) culture-positive tissues. All tissues from culture-negative animals tested negative when using acid-fast and IHC staining. The sensitivity of these 2 tests in detecting M. avium subsp. paratuberculosis in culled dairy cows was not significantly different, and the tests exhibited substantial to almost perfect agreement. Both tests were much less sensitive than bacterial culture, detecting less than 6% of tissues positive compared with culture.

Cisplatin, gentamicin, and p-aminophenol induce markers of endoplasmic reticulum stress in the rat kidneys.

In vitro evidence of the involvement of the endoplasmic reticulum (ER) during drug-induced renal toxicity is accumulating. ER stress and ER-mediated cell death markers have been reported after exposure of renal cells to model toxicants and nephrotoxic drugs in various in vitro models, but in vivo experiments with clinically relevant nephrotoxic compounds are lacking. In order to determine the relevance of the in vitro findings, markers of ER stress (XBP1 messenger RNA processing and protein expression; GRP78 and GRP94 upregulation) and ER-mediated cell death (caspase-12 and calpain activation) were examined in kidney tissue of rats exposed to nephrotoxic doses of cisplatin (CIS), gentamicin (GEN), and p-aminophenol (PAP), a nephrotoxic metabolite of acetaminophen. XBP1 signaling was observed with all three drugs and was associated with increased expression of GRP94 and GRP78 in GEN- and PAP-treated animals, but surprisingly not after CIS exposure. m-Calpain expression was increased after 7 days of CIS treatment, whereas it was decreased in PAP-treated rats. Caspase-12 cleavage products were increased after CIS, GEN, and PAP administration. The results of this study demonstrate that three clinically relevant nephrotoxic drugs are all associated with changes in markers of ER stress and ER-mediated cell death in vivo. Further investigation is warranted to determine the role of the ER, the calpain system, and caspase-12 in drug-induced renal cell death.

Calpain inhibition but not reticulum endoplasmic stress preconditioning protects rat kidneys from p-aminophenol toxicity.

p-Aminophenol (pAP, 225 mg/kg) administration to rats induced renal failure and has been associated with markers of endoplasmic reticulum (ER) stress, as well as calpain and caspase-12 activation in kidneys. To determine the importance of ER stress and calpain during pAP-induced nephrotoxicity, rats were pretreated with low, nontoxic, doses of ER stress inducers or with the selective calpain inhibitor PD150606 (3 mg/kg). Prior ER stress induced by tunicamycin and oxidized dithiothreitol did not result in protection against renal failure, but PD150606 administration was protective and decreased significantly the rise in creatinine and blood urea nitrogen observed after 24-h post-pAP administration. pAP-induced XBP1 upregulation was not modified by calpain inhibition, but a trend to lower GRP94 induction was determined, suggesting that pAP-induced ER stress was mostly calpain independent. In contrast, pAP-induced caspase-12 cleavage products were significantly decreased with PD150606 pretreatment, demonstrating that caspase-12 activation was calpain dependent. This study reveals the importance of calpain in pAP-induced renal failure. Further research with other nephrotoxicants needs to be performed to determine if calpain activation is a common feature of drug-induced renal failure.