Patency period of a metallic ureteral stent and its determinants in patients with malignant ureteral obstruction: a prospective review

Background Malignant ureteral obstruction caused by extrinsic compression of a primary malignant tumour or by metastatic disease is an indicator of poor prognosis with a median life expectancy of about one year. We examined clinical outcomes following Resonance Metallic Ureteral Stent (Cook Medical, Bloomington, IN) placement in patients with malignant ureteral obstruction. Methods This was a prospective study of patients with malignant ureteral obstruction who underwent Resonance Metallic Ureteral Stent placement from April 2016 to March 2021. We registered 21 patients (27 collecting systems) with malignant ureteral obstruction and observed them prospectively. The patients first underwent polymer ureteral stent placement followed by replacement with a metallic ureteral stent one month later. Primary outcome was the metallic ureteral stent patency period based on both serum creatinine and the level of hydronephrosis; secondary outcomes were factors affecting patency period and stent-related complications such as symptoms of obstruction (flank pain), bladder irritation, haematuria, and urinary tract infection (presence or absence of fever). Results The study comprised 21 patients (six men, 15 women) with a mean age of 72 years. The median stent patency period in days was not available (NA) (95% CI 210–NA) due to the inability to extract this value from the Kaplan–Meier curve because the event rate did not reach 50%, and the one-year patency rate was 59.2% (95% CI 23.2–82.9). A normal serum creatinine (0.65 to 1.07 mg/dL for men and 0.46 to 0.79 mg/dL for women) one week after polymer ureteral stent placement was a significant factor affecting the long-term metallic ureteral stent patency period. There were no major complications. Conclusion The Resonance Metallic Ureteral Stent was effective and safe for patients with malignant ureteral obstruction. A normal serum creatinine level one week after placement of a polymer ureteral stent may predict a longer patency period of metallic ureteral stents in patients with malignant ureteral obstruction.

Poststreptococcal Glomerulonephritis without Hypertension in a Patient with Concealed Skin Lesions

Poststreptococcal Glomerulonephritis (PSGN) is an acute inflammation of renal glomerular parenchyma and is sequelae of pharyngitis or skin infection caused by nephritogenic strains of group A beta-Haemolytic Streptococcus. PSGN is conventionally diagnosed based upon clinical findings and demonstration of recent streptococcal infection by a positive skin/throat culture or serologic tests. Hereby, authors present a case of PSGN in an 18-year-old normotensive male is reported who presented with anasarca. On evaluation, the patient had subnephrotic range proteinuria without haematuria and normal serum creatinine. Concealed healing skin lesions in the gluteal region, suggestive of impetigo were noted and hence, arrived at the diagnosis of PSGN. He was treated with intravenous antibiotics, following which symptoms improved. Young patients with acute presentation of oedema or proteinuria with possible renal cause warrants thorough head to foot examination for unseen skin lesions in otherwise overlooked areas. PSGN responds promptly with early antibiotic therapy.

Drug Utilization in Critically ill Adults with Augmented Renal Clearance Compared to Normal Renal Clearance: Implications for use of Antimicrobials with Predominant Renal Excretion

Background: Critically ill adults have augmented renal clearance, (ARC) decreasing the systemic circulation of drugs with predominant renal elimination. The phenomenon of ARC is crucial for antimicrobial drugs as it hinders with the therapeutic response and aids the development of antimicrobial resistance. We carried out the present study to assess the impact of ARC in an intensive care unit (ICU) of a tertiary care hospital. Methods: This was a prospective observational study carried out in critically ill patients with normal serum creatinine without any history of renal disease. Details on their demographic characteristics, clinical diagnoses, laboratory parameters including trough levels of vancomycin and gentamicin, ICU length of stay and clinical outcomes (discharged alive/death) were obtained. Creatinine clearance (Crcl) was estimated from 24-hour urine creatinine. Monte Carlo simulation test with 100000 iterations was used for predicting serum vancomycin trough levels with the observed Crcl. Results: Eighty patients were recruited in the study of which 52.5% had ARC. Patients in younger age and body weight were observed with a trend to have ARC. No significant differences were observed in any of the drug classes prescribed between patients with and without ARC, including the systemic antimicrobials. Although the observed serum trough levels of vancomycin in patients with ARC did not differ significantly from those without ARC, Monte Carlo simulation predicted that 90% of patients with ARC were likely to have trough levels between 5.63 and 7.85 mg/dl while those without ARC may have it between 7.75 to 9.82 mg/dl. Conclusion: Significant proportion of critically ill adults exhibit ARC and such patients are more likely to achieve lower trough concentrations of vancomycin than recommended. All critically ill adults with normal serum creatinine are be screened for ARC using urine creatinine as soon as possible for appropriate adjustment in the dosage regimen of antimicrobials with predominant renal elimination.

Anca-associated crescentic glomerulonephritis in a child with isolated renal involvement

ABSTRACT Pauci-immune glomerulonephritis (GN) is more common in elderly people compared to children and the etiology is not completely understood yet. Antineutrophil cytoplasmic antibody (ANCA) positivity occurs in 80% of the patients. We report a case of a 7-year-old girl who presented with malaise and mildly elevated creatinine diagnosed as ANCA-associated pauci-immune crescentic glomerulonephritis with crescents in 20 of 25 glomeruli (80%). Of these 20 crescents, 12 were cellular, 4 fibrocellular, and 4 globally sclerotic. She did not have purpura, arthritis, or systemic symptoms and she responded well to initial immunosuppressive treatment despite relatively severe histopathology. The patient was given three pulses of intravenous methylprednisolone (30 mg/kg on alternate days) initially and continued with cyclophosphamide (CYC; 2 mg/kg per day) orally for 3 months with prednisone (1 mg/kg per day). In one month, remission was achieved with normal serum creatinine and prednisone was gradually tapered. The case of this child with a relatively rare pediatric disease emphasizes the importance of early and aggressive immunosuppressive treatment in patients with renal-limited ANCA-associated pauci-immune crescentic GN even if with a mild clinical presentation. As in our patient, clinical and laboratory findings might not always exactly reflect the severity of renal histopathology and thus kidney biopsy is mandatory in such children to guide the clinical management and predict prognosis.

Elevation of serum creatinine in a renal transplant patient following oral creatine supplementation

We report the case of a renal transplant recipient presenting with elevated serum creatinine levels whilst taking oral creatine ethyl ester (CEE), but not creatine monohydrate (CM). Standard investigations for allograft dysfunction, including Doppler ultrasound and renal biopsy, were normal. Serum creatinine normalized following cessation of the supplement. CM is poorly absorbed and does not affect creatinine. In contrast, CEE is converted and absorbed as creatinine, elevating serum levels. In such cases, creatinine is not a valid surrogate for glomerular filtration rate (GFR). Alternate methods of GFR measurement should be considered and a rigorous clinical and drug history taken.