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Anti-LDL Receptor-Related Protein 2 (Anti-LRP2) nephropathy is a rare form of kidney disease that affects the older patients and is characterized with acute kidney injury (AKI) and progressive renal tubular injury associated with IgG immune complex deposits along the basement membrane of proximal tubules, and circulating autoantibodies to the proximal tubule brush border protein LRP2 (megalin). We present the case of a 79-year-old man who was hospitalized for worsening malaise, abdominal distention and bilateral lower extremity edema, diagnosed with AKI and had nephrotic range proteinuria. Percutaneous kidney biopsy revealed tubulointerstitial nephritis with IgG immune complex deposits along the basement membrane of proximal tubules and brush borders. Immunofluorescence staining for LRP2 (megalin) showed similar granular tubular basement membrane deposits along the proximal tubules and proximal tubule brush borders. Electron microscopy revealed global podocyte foot process effacement. The patient was started on oral prednisolone 1 mg/kg and rituximab at a dose of 375 mg/m 2 once weekly for 4 weeks with gradual tapering of prednisone. This case with AKI and nephrotic syndrome highlights the significant morphologic overlap with minimal change disease and anti-LRP2 nephropathy, which is associated with autoantibodies to the tubular brush border protein LRP2/megalin.

This article updates the qualitative research on Iran reported in the 2012 article by Tong et al. "The experiences of commercial kidney donors: thematic synthesis of qualitative research" (Tong et al. in Transpl Int 25:1138-1149, 2012). The basic approach used in the Tong et al. article is applied to a more recent and more comprehensive study of Iranian living organ donors, providing a clearer picture of what compensated organ donation is like in Iran since the national government began regulating compensated donation. Iran is the only country in the world where kidney selling is legal, regulated, and subsidized by the national government. This article focuses on three themes: (1) coercion and other pressures to donate, (2) donor satisfaction with their donation experience, and (3) whether donors fear social stigma. We found no evidence of coercion, but 68% of the paid living organ donors interviewed felt pressure to donate due to extreme poverty or other family pressures. Even though 27% of the living kidney donors interviewed said they were satisfied with their donation experience, 74% had complaints about the donation process or its results, including some of the donors who said they were satisfied. In addition, 84% of donors indicated they feared experiencing social stigma because of their kidney donation.

Transplantation remains the modality of choice for patients with end stage renal disease (ESRD). However, while there has been a steady rise in the number of patients with ESRD the supply of donors (combine living and deceased) has fallen far behind the need, resulting in an increasing number of qualified patients remaining on the wait-list, and thousands being removed from the list every year because of death or becoming too sick for transplantation. This has also fed to transplant tourism around the world. Several countries have implemented a variety of policies to overcome their organ shortage that are presented in this article. There is an urgent need for developing policies geared to the cultural norms of different societies and universally accepted ethical principles to remedy this public health issue.

Introduction: Earlier reports indicated that gentamicin should not be mixed with heparin due to precipitation and drug mixture incompatibility. With the recent increased interest in antibiotic lock technique for prophylaxis or adjuvant therapy for hemodialysis catheter-associated infections, it became prudent to reexamine the issue., Method: A mixture of gentamicin (100 µg/mL) and heparin (5,000 U/mL) in normal saline was stored for up to 4 weeks at 4ºC. Gentamicin concentration and bactericidal and anticoagulant activities were measured for up to 4 weeks of storage., Results: The mixture did not show any turbidity or precipitation after fresh preparation, at 48 hours or 4 weeks of storage at 4ºC. Gentamicin concentration (mean ± SD) was 89 ± 7.5 µg/mL, 87 ± 1.0 µg/mL and 85 ± 3.0 µg/mL; gentamicin bactericidal activity was at 1:256 ± 0, 1:256 ± 0 and 1:213 ± 74 dilutions, after fresh preparation, at 48 hours or 4 weeks of storage at 4ºC, respectively (p=NS). Heparin anti-Xa activity was 7,500 ± 990 U/mL and 6,700 ± 707 U/mL, fresh mixture vs. after 4 weeks of storage at 4ºC, respectively (p=NS)., Conclusion: In our in vitro experiments we showed that a mixture of gentamicin (100 µg/mL) and heparin (5,000 U/mL) in normal saline retained its gentamicin concentration, bactericidal activity and anticoagulant activity for up to 4 weeks of storage at 4ºC. We also present a brief review of the literature on this subject.

We present the case of a patient with chronic hepatitis C and diabetes, who rapidly progressed to end stage renal disease upon initiation of IFNalpha therapy for his HCV infection. A kidney biopsy revealed advanced collapsing glomerulopathy.

Background: The anion gap (AG) is an important tool in the evaluation of metabolic acidosis. It is affected by many variables including serum albumin and globulin concentrations. HIV patients may have lower serum albumin and higher serum globulin concentrations. We hypothesized that the AG in HIV patients may differ from that of normal controls., Patients and Methods: We reviewed medical records of 248 stable HIV patients and compared their laboratory variables to 312 patients being evaluated for routine health maintenance in an outpatient setting., Results: The average serum albumin concentration was not different in patients with HIV and normal controls (43 +/- 6 g/L vs. 45 +/- 4 g/L). The serum globulin concentration was significantly higher in the HIV patients when compared with that of normal controls (37 +/- 9 g/L vs. 28 +/- 6 g/L; p<0.05). The AG in the HIV patients was significantly lower than that of normal controls (9.4 +/- 1.9 mmol/L vs. 10.8 +/- 2.7 mmol/L; p<0.05). The slope of the regression line that describes the inverse relationship between serum globulin and AG was 0.147 mmol per g/L. Using this slope, AG could be adjusted for abnormal serum globulin levels: adjusted anion gap = anion gap + 0.147 x (globulin - 29)., Conclusion: Our results indicate that the AG is lower in HIV patients and that this decrement may be due to the increase in serum globulin concentrations. Since a high serum AG metabolic acidosis may be masked by a deceitfully normal AG in patients with elevated serum globulin concentrations, calculation of corrected AG should be undertaken to avoid a costly delay in diagnosis and treatment.

We present 2 new cases of pasteurella multocida induced peritonitis in patients on long term CCPD. We also briefly review the literature on a total of 16 cases (including the present 2 cases) reported in the English literature.

Background: Iron deficiency is a common and important cause of poor response to erythropoietin in patients with severe chronic renal failure (CRF). Oral iron supplements fail to correct iron deficiency in these patients. Ferric gluconate has a low side effect profile, however the recommended dose of 62.5 to 125 mg per treatment is not practical for patients who are not on hemodialysis (HD)., Methods: We retrospectively analyzed the incidence rate of side effects associated with 250 mg of ferric gluconate infused over 1 to 4 hrs. Seventy-nine treatments were administered to 40 patients who had severe CRF. Five patients had received treatments on consecutive days (2 to 4 treatments)., Results: Four treatments in two patients were associated with side effects, which included diarrhea, vomiting, low back pain, hypotension and burning sensation in feet. The duration of infusion did not influence the side effect profile., Conclusion: Our preliminary results suggest that 250 mg of ferric gluconate infused over 14 hrs may be safe with infrequent side effects (5%). It is also more convenient and practical for patients who are not on maintenance HD.

We present a 77-year-old male with moderate chronic renal insufficiency from diabetic nephropathy who developed severe metabolic acidosis and life threatening hyperkalemia on treatment with regular dose of trimethoprim-sulfamethoxazole (TMP-SMZ) for urinary tract infection. The metabolic acidosis and hyperkalemia resolved upon appropriate medical intervention and discontinuation of TMP-SMZ. While hyperkalemia has commonly been reported with high dose of TMP-SMZ, severe metabolic acidosis is quite uncommon with regular dose TMP-SMZ. We emphasize that patients with renal tubular acidosis (RTA), renal insufficiency, aldosterone deficiency, old age with reduced renal mass and function, and angiotensin converting enzyme (ACE)-inhibitor therapy are at high risk of developing these severe and potentially life threatening complications.

The microvillous membrane of human placental syncytiotrophoblast cells contains a high ATPase activity. The purpose of this study was to characterize this activity and to investigate the presence of vacuolar type H+ ATPase in this membrane. Intact brush border membrane vesicles strongly hydrolyzed ATP, reflecting the presence of ATPase on the external side of the membrane. The ATPase activity was entirely Mg2+ dependent and increased with pH. At pH 7.5, Vmax was 31.0 +/- 1.7 mumol/mg/20 min and Km 0.18 +/- 0.03 mM ATP. Hydrolysis of ATP was not influenced by the presence of bicarbonate or alkaline phosphatase inhibitors, but at pH 8 it decreased by half following addition of 100 microM dicyclohexylcarbodiimide (DCCD). At pH 7.5, 1 mM N-ethylmaleimide (NEM) depressed this activity by less than 5%. Opening the membrane vesicles with 0.1% desoxycholate (DOC) or Triton-X neither revealed any additional ATPase activity nor altered the low sensitivity to NEM. Treatment of these membranes with 1% cholate decreased the ATPase activity by more than 70% and did not enhance the sensitivity of ATP hydrolysis to NEM. 10(-7) M Bafilomycin, which reduced by 56 +/- 9% the ATPase activity in dog kidney brush border membranes treated with 0.1% DOC, had no effect on placental brush border membranes subjected to the same procedure. Finally, neither immunocytochemical staining using monoclonal antibody to the M(r) 31000 subunit of V-type H+ ATPase, nor electron microscopic examination detected the presence of H(+) ATPase in placental membranes. In conclusion, the placental brush border membrane is the site of a strong "ecto" ATPase activity which is partially DCCD sensitive.(ABSTRACT TRUNCATED AT 250 WORDS)

This study examines the effects of acute in vitro acid-base disorders on Na+/H+ and H(+)-ATPase transporters in rabbit kidney proximal tubules (PT). PT suspensions were incubated in solutions with varying acid base conditions for 45 min and utilized for brush border membrane (BBM) vesicles preparation. BBM vesicles were studied for Na+/H+ exchange activity (assayed by 22Na+ influx) or abundance (using NHE-3 specific antibody) and H(+)-ATPase transporter abundance (using antibody against the 31 kDa subunit). The Na+/H+ exchanger activity increased by 55% in metabolic acidosis (pH 6.5, HCO3- 3 mM) and decreased by 41% in metabolic alkalosis (pH 8.0, HCO3- 90 mM). The abundance of NHE-3 remained constant in acidic, control, and alkalotic groups. H(+)-ATPase abundance, however, decreased in metabolic acidosis and increased in metabolic alkalosis by 57% and 42%, respectively. In PT suspensions incubated in isohydric conditions (pH 7.4), Na+/H+ exchanger activity increased by 29% in high HCO3- group (HCO3- 96 mM) and decreased by 16% in the low HCO3- groups (HCO3- 7 mM. The NHE-3 abundance remained constant in high, normal, and low [HCO3-] tubules. The abundance of H(+)-ATPase, however, increased by 82% in high [HCO3-] and decreased by 77% in the low [HCO3-] tubules. In PT suspensions incubated in varying pCO2 and constant [HCO3-], Na+/H+ exchanger activity increased by 35% in high pCO2 (20% pCO2, respiratory acidosis) and decreased by 32% in low pCO2 (1.5% pCO2, respiratory alkalosis) tubules. The NHE-3 abundance remained unchanged in high, normal, and low pCO2 tubules.(ABSTRACT TRUNCATED AT 250 WORDS)