[Investigation of the safety and usefulness of a renal biopsy for older elderly patients ≥75 years old].

AIM: We herein report the safety and usefulness of a kidney biopsy in older elderly patients (≥75 years old). METHODS: A retrospective observational study was conducted in older elderly patients who had received a renal biopsy at the Department of Nephrology, Shimane University Hospital, from January 1, 2008, to December 31, 2018. The native renal biopsy results of 52 later-stage elderly patients were analyzed (29 men and 23 women). RESULTS: The most common indication for a renal biopsy was nephrotic syndrome (n = 22), followed by rapidly progressive glomerulonephritis (n = 12) and asymptomatic urinary abnormalities (n = 12). The most common pathological diagnosis was membranous nephropathy (n = 12), followed by ANCA-associated nephritis (n= 8), minimal change nephrotic syndrome (6 case), membranoproliferative glomerulonephritis (n = 5), IgA nephropathy (n = 4), and diabetic nephropathy (n = 3). The concordance rate between the clinical and pathological diagnoses was 53.8%. The only complication of the renal biopsy was hemorrhaging requiring blood transfusion (1 patient; 1.9%). The hemoglobin level decreased by 0.5±0.05 d/dL after the biopsy. CONCLUSION: The rate of serious complications associated with a renal biopsy was comparable to that in previous reports in younger patient. Renal biopsies can therefore be safely performed even in older elderly patients. The concordance rate of the clinical and pathological diagnoses was about 50%. Therefore, renal biopsies should be performed in older elderly patients when necessary.

Peritoneal dialysis-associated infection caused by Mycobacterium abscessus: a case report.

BACKGROUND: Peritoneal dialysis (PD)-associated infection caused by Mycobacterium spp. is rare. Mycobacterium abscessus is one of the most resistant acid-fast bacteria, and treatment is also the most difficult and refractory. Thus, we report a case of PD-associated peritonitis caused by Mycobacterium abscessus that was difficult to treat and led to PD failure. CASE PRESENTATION: We recently encountered a 56-year-old man who developed PD-associated infection. We initially suspected exit-site infection (ESI) and tunnel infection (TI) caused by methicillin-resistant coagulase-negative Staphylococcus. However, antibiotic therapy did not provide any significant improvement. Thus, we performed simultaneous removal and reinsertion of a PD catheter at a new exit site. The patient subsequently developed peritonitis and Mycobacterium abscessus was detected in the peritoneal effluent. Thus, the reinserted catheter was removed, hemodialysis was started, and the patient was eventually discharged. CONCLUSIONS: In cases of refractory ESI or TI, it is important to consider non-tuberculous mycobacteria as the potentially causative organism. Even if acid-fast bacterial staining is negative or not performed, detection of Gram-negative bacillus may lead to suspicion and early identification of Mycobacterium spp. In PD-associated infection by Mycobacterium abscessus, catheter removal is necessary in many cases. Simultaneous removal and reinsertion of the catheter is not recommended, even in cases of ESI or TI. Reinsertion should only be attempted after complete resolution of peritoneal symptoms. After removal of the catheter, careful follow-up is necessary, paying attention to complications such as wound infection, peritonitis, and ileus. In addition, the selection and treatment period of antibiotics in PD-associated infection by Mycobacterium abscessus remains unclear, and it is an important topic for future discussion.

Indications for Percutaneous Drainage in Patients with Huang Class 3B Emphysematous Pyelonephritis: A Case Report and Literature Review.

Emphysematous pyelonephritis (EPN) is a severe urinary tract infection common in patients with diabetes. Nephrectomy is recommended when the Huang classification is ≥3B. We herein report a case in which nephrectomy was avoided using antimicrobial agents and percutaneous drainage (PCD). A 59-year-old man was diagnosed with EPN (Huang classification 3B). The causative bacteria were Escherichia coli. Despite high-risk factors, EPN was cured with kidney preservation and PCD because the emphysema and abscess were not extensive. Thus, PCD should be considered in patients with Huang Class 3B EPN and high-risk factors if emphysema and abscess are not extensive.

Osteomalacia caused by atypical renal tubular acidosis with vitamin D deficiency: a case report.

Osteomalacia is a systemic metabolic bone disease. Hypophosphatemia is one of the most important causes of impaired mineralization. Here, we describe a case of osteomalacia associated with atypical renal tubular acidosis. A 43-year-old woman was admitted to our hospital due to sustained unrelieved bilateral flank pain. She had a history of fragile fracture with vitamin D deficiency and had been treated with active vitamin D. On admission, she presented with hypophosphatemia, hypocalcemia, high bone-specific alkaline phosphatase level, bone pain, and low bone mineral density. Multiple areas of uptake were also confirmed by bone scintigraphy, and she was diagnosed with osteomalacia. An increased dose of alfacalcidol was initiated for her vitamin D deficiency; her symptoms remained unstable and unrelieved. Her blood gas examination revealed metabolic acidosis without an increase in the anion gap (HCO3- 11.8 mEq/L, anion gap 3.2 mEq/L). Tubular dysfunction, tubular damage, kidney stones, and inadequate urinary acidification were all observed, suggesting the presence of renal tubular acidosis from a combination of both distal and proximal origin. She also had overt proteinuria, decreased renal function, and hypothalamic hypogonadism. In addition to alfacalcidol, sodium bicarbonate and oral phosphorus supplementation were initiated. After this prescription, her pain dramatically improved in association with the restoration of acid-base balance and electrolytes; renal dysfunction and proteinuria were unaltered. This case indicated that careful assessments of tubular function and acid-base balance are essential for the management of osteomalacia in addition to the evaluation of the calcium/phosphate balance and vitamin D status.

A Remarkable Elevation in the Procalcitonin Levels Due to Diabetic Ketoacidosis in a Hemodialysis Patient.

Procalcitonin (PCT), a marker of the inflammatory response during infections, can be elevated by diabetic ketoacidosis (DKA). A male patient in his 50s with diabetic nephropathy on hemodialysis presented with vomiting and a reduced level of consciousness and was diagnosed with DKA. His PCT level was markedly elevated, but bacterial cultures (blood, urine, and stool) were negative. The PCT level decreased after DKA improvement. In this patient, DKA probably enhanced the PCT levels. As DKA can increase the PCT levels, an elevation of the PCT levels in DKA patients may not be indicative of infectious diseases, and non-infectious causes of DKA should therefore be considered.