MPO-ANCA-positive conversion and microscopic polyangiitis development in idiopathic interstitial pneumonia: a case report.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a systemic autoimmune disease characterized by necrotizing inflammation of the small blood vessels. ANCA-associated vasculitis is subclassified into three variants: granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, and microscopic polyangiitis (MPA). Myeloperoxidase (MPO) ANCA is a marker antibody for MPA. Interstitial pneumonia (IP) is occasionally complicated with MPA. However, only a few cases of idiopathic IP develop MPO-ANCA-positive conversion and MPA. Therefore, we present a case of a 70-year-old Japanese man with idiopathic IP who developed MPO-ANCA-positive conversion and MPA. We performed renal biopsy, which revealed pauci-immune crescentic glomerulonephritis. The patient was treated with intravenous methylprednisolone pulse therapy and oral prednisone, and the patient's laboratory data gradually improved with steroid therapy. The association between the production of MPO-ANCA and IP remains unclear, and the present case suggests that IP plays a role in inducing MPO-ANCA production. Patients with idiopathic IP should be followed-up carefully for an examination of increased MPO-ANCA levels and MPA development. In addition, early gastric cancer was detected during upper gastrointestinal endoscopy in our case, and it could also be important not to miss malignancy in patients with ANCA-associated vasculitis.

Inhibition of sodium-glucose cotransporter 2 suppresses renal stone formation.

BACKGROUND AND AIMS: Nephrolithiasis is a common renal disease with no effective medication. Sodium-glucose cotransporter-2 (SGLT2) inhibitors, an anti-diabetic agent, have diuretic and anti-inflammatory properties and could prevent nephrolithiasis. Here, we investigated the potential of SGLT2 inhibition against nephrolithiasis using large-scale epidemiological data, animal models, and cell culture experiments. METHODS: This study included the data of diabetic patients (n = 1,538,198) available in the Japanese administrative database and divided them according to SGLT2 inhibitor prescription status. For animal experiments, renal calcium oxalate stones were induced by ethylene glycol in Sprague-Dawley rats, and phlorizin, an SGLT1/2 inhibitor, was used for the treatment. The effects of SGLT2-specific inhibition for renal stone formation were assessed in SGLT2-deficient mice and a human proximal tubular cell line, HK-2. RESULTS: Nephrolithiasis prevalence in diabetic men was significantly lower in the SGLT2 inhibitor prescription group than in the non-SGLT2 inhibitor prescription group. Phlorizin attenuated renal stone formation and downregulated the kidney injury molecule 1 (Kim1) and osteopontin (Opn) expression in rats, with unchanged water intake and urine volume. It suppressed inflammation and macrophage marker expression, suggesting the role of the SGLT2 inhibitor in reducing inflammation. SGLT2-deficient mice were resistant to glyoxylic acid-induced calcium oxalate stone formation with reduced Opn expression and renal damages. High glucose-induced upregulation of OPN and CD44 and cell surface adhesion of calcium oxalate reduced upon SGLT2-silencing in HK-2 cells. CONCLUSION: Overall, our findings identified that SGLT2 inhibition prevents renal stone formation and may be a promising therapeutic approach against nephrolithiasis.

Safety of peritoneal dialysis catheter surgery under dexmedetomidine and local anesthesia for elderly patients in Japan: a single-center prospective cohort study.

BACKGROUND: The number of patients aged ≥ 75 years and who need renal replacement therapy is steadily increasing. The study aimed to determine the safety of open surgery for peritoneal dialysis (PD) catheter placement in such patients. METHODS: This prospective cohort study included patients who underwent PD catheter placement by open surgery under dexmedetomidine (DEX) and local anesthesia at our institution from January 2015 to February 2021. Patients were divided into the following two groups according to age at the time of surgery: ≥ 75 years (group A) and < 75 years (group B). We compared the perioperative and postoperative complications (i.e., time to the first PD-related peritonitis and catheter obstruction requiring surgical intervention within 1 year) between the groups. RESULTS: A total of 118 patients were categorized into groups A (n = 65) and B (n = 53). No significant intergroup differences were observed in the postoperative fever, total duration of surgery, perioperative hemoglobin decrease, changes in the white blood cell count and C-reactive protein, postoperative catheter leakage, postoperative hospital stay, time to the first PD-related peritonitis, and catheter obstruction requiring surgical intervention within 1 year. CONCLUSIONS: The surgery for PD catheter placement by open surgery under DEX and local anesthesia in elderly patients is safe and effective.

The Impact of Preoperative Risk Factors on Peritoneal Dialysis-Related Peritonitis: A Single-Center Prospective Study in Japan.

Background and Objectives: Peritoneal dialysis (PD)-related peritonitis is a critical problem. However, preoperative risk factors for PD-related peritonitis have not been established. Thus, we aimed to determine the preoperative risk factors for PD-related peritonitis. Materials and Methods: This is a single-center prospective observational study. All peritonitis episodes during the study period were recorded, and preoperative and intraoperative clinical parameters were compared between patients with and without peritonitis to examine risk factors for PD-related peritonitis. Furthermore, subcutaneous and abdominal fat volumes were evaluated using computed tomography. Results: Among a total of 118 patients, 24 patients developed peritonitis. The proportion of male patients (83% vs. 61%, p = 0.04), body mass index (25 vs. 22 kg/m2, p = 0.04), and subcutaneous fat area (120 vs. 102 cm2, p = 0.01) were significantly higher and the proportion of patients living with family members (75% vs. 94%, p = 0.02) was significantly lower in the peritonitis group than in the non-peritonitis group. There were no significant differences in age, operation method, surgeon experience, previous abdominal surgery, medical history of diabetic nephropathy, serum albumin level, and renal function between the two groups. Conclusions: Male patients with high subcutaneous fat who are living alone might be at higher risk of PD-related peritonitis. These characteristics might be useful in risk assessment and patient education before PD induction.

Efficacy of LDL apheresis for the treatment of cholesterol crystal embolism: A prospective, controlled study.

This study was performed to evaluate the efficacy and safety of LDL apheresis (LDL-A) for the treatment of cholesterol crystal embolism (CCE) after cardiovascular procedures. We conducted a prospective multicenter study of 34 patients with CCE and 15 historical control patients. The present participants underwent six sessions of LDL-A for 4 weeks and underwent medical therapy with corticosteroids and statins. The mean creatinine concentration and estimated glomerular filtration rate at baseline were 3.82 ± 2.29 mg/dL and 17.8 ± 9.9 mL/min/1.73 m2 , respectively. The prevalence of maintenance dialysis at 24 weeks was significantly lower in the present participants than in the historical controls (3.1% vs. 40.0%, respectively; p < 0.0001), but the mortality rate at 24 weeks was comparable (19% vs. 33%, respectively). Although 45 adverse events occurred in 23 participants, there were no unexpected adverse events. LDL-A for CCE reduces the prevalence of maintenance dialysis 24 weeks later and is well tolerated. This study was registered in the Japan Registry of Clinical Trials (jRCTs022180029) and clinicaltrials.gov (NCT01726868).

Efficacy of low-density lipoprotein apheresis combined with corticosteroids for cholesterol crystal embolism.

BACKGROUND: Corticosteroids have been widely used in patients with cholesterol crystal embolism (CCE) and low-density lipoprotein apheresis (LDL-A) was reported to reduce the risk of end-stage renal disease in patients with CCE. This study was designed to evaluate the renoprotective effects of LDL-A in combination with corticosteroids in patients with CCE. METHODS: Thirty-five patients with CCE who, between 2008 and 2013, had shown renal deterioration after vascular interventions were retrospectively evaluated. All patients received corticosteroids; of these, 24 also received LDL-A and 11 did not, designated LDL-A and control groups, respectively. Differences in eGFR (ΔeGFR), 3 months and 1 year after CCE diagnosis, were compared in the two groups. RESULTS: The median estimated glomerular filtration rate (eGFR) in all patients was 38.9 [interquartile range (IQR) 31.9-49.4] ml/min/1.73 m2 at baseline (before vascular intervention). At diagnosis, it was 14.4 (IQR 11.3-21.8) ml/min/1.73 m2. The initial corticosteroid dose was 0.34 ± 0.10 mg/kg/day. The mean number of LDL-A treatment sessions in the LDL-A group was 4.3 ± 1.8. eGFR was increased significantly after LDL-A treatments, from 15.0 (IQR 12.3-20.1) to 19.6 (IQR 14.3-23.6) ml/min/1.73 m2 (P < 0.05). ΔeGFR tended to be higher in the LDL-A than in the control group at 3 months [median 6.5 (IQR 5.1-9.3) vs. 2.6 (IQR -0.6 to 6.3) ml/min/1.73 m2, P = 0.095] and was significantly higher at 1 year [median 7.5 (IQR 5.4-8.7) vs. 2.2 (IQR -3.8 to 5.1) ml/min/1.73 m2, P = 0.019]. CONCLUSIONS: LDL-A plus corticosteroids may restore deteriorated renal function better than corticosteroids alone in patients with CCE.

Low-Density Lipoprotein Apheresis Ameliorates Renal Prognosis of Cholesterol Crystal Embolism.

Drugs such as corticosteroids and statins have been used to treat cholesterol crystal embolism (CCE), but the prognosis remains poor. This study evaluated the efficacy of low-density lipoprotein apheresis (LDL-A) in patients with CCE. Patients with CCE who showed renal deterioration after vascular interventions were studied retrospectively. Information on demographic variables, clinical measurements, and medication use was collected. The outcomes were incidence of maintenance dialysis and mortality at 24 weeks. A total of 49 patients with CCE were included, among whom 37 (76%) were diagnosed pathologically and the remainder were diagnosed clinically. The median estimated GFR at baseline and at diagnosis were 40.5 and 13.4 mL/min per 1.73 m(2) , respectively. Corticosteroids were used in 42 patients (86%), statins in 30 patients (61%), and angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in 29 patients (59%). LDL-A was performed in 25 patients (LDL-A group), and not in 24 patients (control group). Smoking (100% vs. 72%, P = 0.02), white blood cell count (8900/mm(3) vs. 7000/mm(3) ) and corticosteroid use (96% vs. 75%) were higher in the LDL-A group compared with the control group, but there were no differences in other demographic and clinical parameters between the groups. Patients in the LDL-A group had a lower incidence of maintenance dialysis (2/25 (8%) vs. 8/24 (33%), P < 0.05), and a trend towards lower mortality (2/25 (8%) vs. 7/24 (29%), P = 0.074). These results suggest that LDL-A decreases the risk of maintenance dialysis in severe renal CCE patients after vascular interventions.