C3 glomerulopathy masquerading as acute postinfectious glomerulonephritis.

We report the case of a 63-year-old man who presented with acute kidney injury, active urine sediment, nephrotic syndrome, and hypocomplementemia after a recent report of a sore throat. Kidney biopsy showed diffuse proliferative and exudative glomerulonephritis with C3-dominant staining by immunofluorescence. Taken together, clinical and pathologic findings were most suggestive of acute postinfectious glomerulonephritis, although the history of full nephrotic syndrome, presence of segmental membranoproliferative features, and absence of classic subepithelial hump-shaped deposits were unusual for this condition. Three months after the initial biopsy, the patient continued to have hypocomplementemia and nephrotic syndrome, prompting a repeated kidney biopsy that showed findings most consistent with C3 glomerulopathy. C3 glomerulopathy is a proliferative pattern of glomerulonephritis characterized by complement deposits that stain solely or dominantly for C3. A subset of cases of C3 glomerulopathy have features that overlap extensively with acute postinfectious glomerulonephritis. Clinicians and pathologists should be aware of the similar findings seen in these 2 conditions.

Daily ultrafiltration results in improved blood pressure control and more efficient removal of small molecules during hemodialysis.

BACKGROUND: Although prior studies have shown that frequent hemodialysis (HD) can lead to improved control of dry weight in end-stage renal disease patients, there are no clinical studies examining whether this can improve blood pressure (BP) control and can also shorten the dialysis time needed to achieve satisfactory removal of small molecules. Several models of wearable dialysis systems are now under various stages of development. These devices present the possibility of hemodialyzing patients to their dry weights. We have built a prototype of a wearable ultrafiltration (UF) device that can provide daily UF. Apart from better fluid control, we hypothesize that separating HD from UF will result in better BP control, and adequate weekly small molecule removal could be achieved with a decreased duration of dialysis. We tested the hypothesis in current HD patients using conventional dialysis equipment. METHODS: Thirteen patients were selected from a large urban HD center. The experimental period consisted of 4 weeks of daily UF (4 days/week of UF alone and 2 days/week of HD with UF). The duration of the HD sessions was increased by 15-30 min to maintain weekly standard Kt/V >2.0. The patients were then returned to their conventional 3 days/week of HD with UF and studied for 4 weeks. Predialysis BPs, interdialytic weight gains, and Kt/V results of the experimental and return periods were compared with those of the 3-month control period. No changes were made in antihypertensive or other medication during the study. RESULTS: During the experimental period, mean arterial pressure decreased from 110 to 95 mm Hg (p < 0.001), systolic BP from 158 to 136 mm Hg (p < 0.001), while interdialytic weight gains were reduced from 3.25 to 1.21 liters (p < 0.0001). During the experimental period, weekly standard Kt/V of 2.16 was achieved in 8.24 h/week of HD, as compared to 11.14 h/week. CONCLUSIONS: Volume control with daily UF results in improved BP control and, by separating the UF function from HD, adequate weekly standard Kt/V >2 can be achieved with twice weekly HD.

The path to wearable ultrafiltration and dialysis devices.

Wearable blood processing devices offer an attractive solution to problems inherent in clinic-based, intermittent end-stage renal disease therapies. What is involved in transitioning even a part of the current clinic-based population to ambulatory therapy has not been clearly enumerated. This paper addresses what a first-generation wearable device might accomplish, how issues of safety will need to be addressed, and what will make the device attractive to, and manageable by, the patient. Medical, technological, and economic issues are identified.

Acute kidney injury in the setting of AIDS, bland urine sediment, minimal proteinuria and normal-sized kidneys: a presentation of renal lymphoma.

Acute kidney injury in HIV patients is primarily related to HIV-mediated viral or immunological disease or to treatment-related toxicity (tenofovir). Neoplasms are a rare cause of non-obstructive acute kidney injury, primarily because when they occur, they manifest as discrete masses and not as diffuse infiltration of the renal parenchyma. Diffusely infiltrating tumors include carcinoma of the renal pelvis invading the renal parenchyma, renal lymphoma, squamous cell carcinoma (from lung) metastasizing to the kidney and infiltrating sarcomatous type of renal cell carcinoma. To be classified as a true case of renal lymphoma, the tumor should have escaped detection on routine imaging preceding biopsy, and lymphoma-associated renal failure/nephrotic proteinuria should have given rise to the indication for kidney biopsy. We present here a case of an acute kidney injury due to renal lymphoma in a patient with acquired immune deficiency syndrome that manifested clinically as bland urine sediment, minimal proteinuria and normal-sized kidneys. Chemotherapy resulted in complete reversal of acute kidney injury.

A novel pathway for the management of hypertension for hospitalized patients.

About 65 million Americans, one fourth of the adult population in the United States, and over 1 billion people worldwide have hypertension (HTN). HTN therefore is present in 1 of every 4 patients admitted to any US hospital. Surprisingly, no guidelines are available for the management of inpatient HTN. Based on a comprehensive search of the literature we are proposing a pathway for the management of HTN in nonpregnant hospitalized patients. The pathway provides a definition and clinical assessment of HTN for patients admitted to the hospital. The assessment is followed by an organ/system based therapeutic approach specifying timing, blood pressure goals, recommended antihypertensive drug therapy and the sequence of add-on drugs. The pathway specifically discusses assessment and management of HTN in patients with (1) acute aortic syndrome, (2) acute neurologic syndrome, (3) acute coronary syndrome, (4) congestive heart failure, (5) renal failure, and (6) secondary forms. Finally, the pathway provides a step by step recommendation for the management of in hospital HTN and of hypertensive emergencies.

Membraneless dialysis--is it possible?

Direct contact between uremic blood and a fluid capable of receiving uremic toxins is possible. Such contact by itself is, however, not beneficial because the selection of molecules that are removed is dependent on diffusion coefficients in blood. This selection is inadequate and would result in the exhaustion of a patient's albumin pool before useful reduction in the urea pool was achieved. Direct contact that is accomplished by sandwiching blood between two layers of a sheathing fluid, followed by diafiltration of the sheathing fluid through conventional membranes and recirculation of the sheathing fluid, is possible. This adaptation of membraneless transport of molecules from blood eliminates almost all contact of blood with solid artificial surfaces and the subsequent diafiltration and recirculation of the sheathing fluid allows precise control of what is removed from the system. Slightly hyperosmotic protein is carried back by the recirculating sheathing fluid. Only solutes and water that pass the diafilter, which operates on a cell-free fluid, are able to leave the system. The system depends strongly on the ability to keep cells out of the sheathing fluid. Preliminary results and earlier reports indicate that this separation is possible and more precise measurements are underway. A quantitative design of a wearable dialyzer based on a circulating sheathing fluid is presented.

Guidelines for the reporting of renal artery revascularization in clinical trials.

Although the treatment of atherosclerotic renal artery stenosis with use of percutaneous angioplasty, stent placement, and surgical revascularization has gained widespread use, there exist few prospective randomized controlled trials (RCTs) comparing these techniques to each other or against the standard of medical management alone. To facilitate this process as well as help answer many important questions regarding the appropriate application of renal revascularization, well-designed and rigorously conducted trials are needed. These trials must have clearly defined goals and must be sufficiently sized and performed so as to withstand intensive outcomes assessment. Toward this end, this document provides guidelines and definitions for the design, conduct, evaluation, and reporting of renal artery revascularization RCTs. In addition, areas of critically necessary renal artery revascularization investigation are identified. It is hoped that this information will be valuable to the investigator wishing to conduct research in this important area.

Guidelines for the reporting of renal artery revascularization in clinical trials.

Although the treatment of atherosclerotic renal artery stenosis with use of percutaneous angioplasty, stent placement, and surgical revascularization has gained widespread use, there exist few prospective randomized controlled trials (RCTs) comparing these techniques to each other or against the standard of medical management alone. To facilitate this process as well as help answer many important questions regarding the appropriate application of renal revascularization, well-designed and rigorously conducted trials are needed. These trials must have clearly defined goals and must be sufficiently sized and performed so as to withstand intensive outcomes assessment. Toward this end, this document provides guidelines and definitions for the design, conduct, evaluation, and reporting of renal artery revascularization RCTs. In addition, areas of critically necessary renal artery revascularization investigation are identified. It is hoped that this information will be valuable to the investigator wishing to conduct research in this important area.