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T K Rao

Publications and source records attributed to T K Rao.

At least 19 recordsLinked to original sources

Human immunodeficiency virus infection and renal failure.

Renal manifestations are an important component of HIV disease. Renal disease significantly contributes to morbidity and mortality in patients with HIV. Great progress has been made in identifying specific glomerular lesions and its pathogenesis. Newer antiretroviral agents offer great promise in preventing renal disease and also in patients with established HIVAN. Survival of patients with HIV and ESRD (irrespective of cause) who are receiving RRT continues to improve over the years. Acute reversible renal failure, a preventable complication, is also declining in hospitalized HIV patients. More and more physicians, who in the past were reluctant to care for patients with HIV and renal failure because of grim prognosis, are now becoming familiar with the renal sequelae and are encouraged by recent favorable results. As knowledge about viruses is expanding, the proper use of newer highly effective antiretroviral and other agents in complicated patients should further improve both the survival and quality of life in patients with HIV infection and renal disease.

AIDS-Associated Nephropathy↗

Acute renal failure syndromes in human immunodeficiency virus infection.

Two major groups of renal complications in human immunodeficiency virus (HIV) disease are a spectrum of disorders that result in potentially reversible acute renal failure, primarily acute tubular necrosis (ATN), and HIV-associated nephropathy (HIVAN), predominantly focal and segmental glomerulosclerosis (FSGS), leading to end-stage renal disease (ESRD). Fluid-electrolyte and acid-base derangements frequently encountered in acquired immune deficiency syndrome (AIDS) are major risk factors for the development of acute renal failure (ARF). HIVAN is an unusual form of poorly responsive glomerular disease characterized by nephrotic syndrome, FSGS, and a rapid fulminant progression to ESRD. ARF syndromes encountered in HIV patients are diverse in nature; many are similar to that in non-HIV subjects, whereas some are more common and unique. In general, HIV disease patients with ARF are younger and much sicker. Although ATN secondary to ischemic and toxic injuries is the commonest ARF syndrome, urinary obstruction is a rare cause of severe renal failure. In many AIDS patients afflicted with complicated infections and multi-organ failure, ATN is a terminal event, whereas in others treated aggressively, ARF is associated with good prognosis. In our large comparative study of severe ARF, recovery of renal function and mortality were determined by patient's general hemodynamic status, and not by the presence or absence of HIV infection. The prognosis of hemolytic uremic and thrombotic thrombocytopenic purpura syndromes often observed in HIV patients is much worse than in non-HIV patients. The syndrome of crystalluria-induced ARF is common, and protease inhibitor induced disease is confined to HIV patients.

AIDS-Associated Nephropathy↗

Uremia therapy in patients with end-stage renal disease and human immunodeficiency virus infection: has the outcome changed in the 1990s?

We conducted a cross-sectional survey to determine the relative course of patients with end-stage renal disease (ESRD) and human immunodeficiency virus (HIV) infection sustained on maintenance hemodialysis. All 34 patients with ESRD and HIV infection receiving hemodialysis in one hospital-based and three community-based outpatient hemodialysis facilities in Brooklyn, NY, were studied. We documented their known duration of HIV infection, duration of ESRD, and hemodialysis prescription, and noted the presence of clinical acquired immunodeficiency syndrome (AIDS). Total CD4 count, serum albumin concentration, and percent reduction of urea (predialysis blood urea nitrogen minus postdialysis blood urea nitrogen, divided by predialysis blood urea nitrogen x 100) were measured. The 34 study subjects (26 men and eight women) included 31 blacks (91%) and three Hispanics (9%) with a mean age of 42 +/- 7.5 years, 29 (85%) of whom had AIDS. Twenty subjects (59%) had a history of intravenous drug abuse. Only six subjects (18%) were receiving an antiretroviral drug (zidovudine = five, dideoxyinosine = one). In 23 subjects (68%), AIDS was diagnosed prior to ESRD and was presumed to be the cause of renal failure (HIV-associated nephropathy). The mean known duration of HIV infection was 50.5 +/- 34 months (median, 48 months); the mean duration of ESRD was 57 +/- 50 months, the mean total CD4 count was 140 +/- 150 cells/microL (median, 70 cells/microL), the mean hematocrit was 28% +/- 5%, and the mean serum albumin concentration was 3.5 +/- 0.37 g/dL. All subjects were receiving erythropoietin for anemia correction. The mean length of the prescribed thrice-weekly hemodialysis sessions was 3.5 +/- 0.4 hours. Our results suggest that the survival of many ESRD patients with HIV infection receiving hemodialysis has improved compared with the uniformly dismal survival rate reported in the 1980s. Decisions on whether to initiate renal replacement therapy in patients with AIDS and advanced renal failure should be individualized because the combination of ESRD and HIV infection does not necessarily signal near-term death.

AIDS-Associated Nephropathy↗

Renal complications in HIV disease.

Renal consequences of HIV disease are diverse: some unique attributable to HIV infection per se and some coincidental reflecting the nature and severity of underlying primary illness. In addition, renal sequelae may also be iatrogenic, owing to a variety of therapeutic agents employed in the management of HIV infection. Renal failure from any cause, both reversible (acute) and irreversible (ESRD), contributes greatly to morbidity and mortality in HIV-infected patients. An understanding of the spectrum of renal derangements is essential for clinicians to manage patients with HIV disease better.

AIDS-Associated Nephropathy↗

Childhood AIDS nephropathy: a 10-year experience.

The objective of this study was to define the demographic, immunologic, and clinical characteristics of children with acquired immunodeficiency syndrome (AIDS) and AIDS nephropathy, and contrast this with the existing adult data. Data from 62 pediatric patients with AIDS who were treated at SUNY Health Science Center, Brooklyn, New York, between 1983 and 1993 were analyzed. Human immunodeficiency virus (HIV) infection was acquired during the neonatal period by vertical transmission (n = 60) or blood transfusion (n = 2). All children with AIDS who exhibited clinical nephropathy died (n = 16), with mean survival of 55.3 months. In contrast, 32 of 56 AIDS patients (70%) who did not manifest nephropathy were alive at the end of the study period. Patients with nephropathy were noted to have significantly lower CD4+ lymphocyte counts than those without nephropathy. These observations suggest that the predominant renal lesion in pediatric patients who acquired HIV infection during the perinatal period is focal segmental glomerulosclerosis, although a variety of other histological lesions were present. As in adults, the survival in children is dismal following the onset of clinical renal disease. In contrast to the adult population in whom multiple risk factors can potentially contribute to AIDS-associated nephropathy, occurrence of nephropathy in children with vertical HIV transmission provides convincing evidence for the pathogenetic role of HIV infection.

AIDS-Associated Nephropathy↗

Outcome of severe acute renal failure in patients with acquired immunodeficiency syndrome.

Among a spectrum of renal disorders encountered in patients infected with the human immunodeficiency virus (HIV), the lesion studied most often has been the glomerular disease known as HIV-associated nephropathy. Of the other coincidental renal perturbations reported, the most significant are a heterogenous group encompassing potentially reversible acute renal failure (ARF), primarily acute tubular necrosis. While HIV-associated nephropathy may frequently be seen in asymptomatic HIV-seropositive individuals, acute tubular necrosis almost always is encountered in patients with clinical acquired immunodeficiency syndrome (AIDS). We analyzed our decade's experience in the management of 146 HIV disease patients with ARF (132 AIDS patients and 14 HIV-seropositive patients) and compared it with a contemporaneous group of 306 non-HIV subjects with ARF. All patients evaluated for ARF between January 1984 and December 1993 by the Renal Division at Kings County Hospital Center, Brooklyn, NY, were reviewed. Only those patients with ARF who reached a serum creatinine concentration of 530 mumol/L or higher were included in the analysis. Ninety-one percent of 146 HIV disease patients with ARF were less than 50 years old compared with only 33% of the 306 non-HIV subjects (P < 0.001). Septicemia was directly or indirectly responsible for 75% of patients with ARF in the AIDS group and for 39% in the non-HIV subjects (P < 0.006). Urinary tract obstruction was the cause of ARF in 54 of 306 (17%) non-HIV patients compared with none in the HIV group (P < 0.00001).(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Associated Nephropathy↗

The efficacy of erythropoietin in human immunodeficiency virus-infected end-stage renal disease patients treated by maintenance hemodialysis.

The superimposition of human immunodeficiency virus (HIV) infection, associated opportunistic infections, and anti-retroviral therapy further worsens the severity of anemia in patients also suffering from end-stage renal disease. A major cause of anemia in renal failure is a deficiency of erythropoietin. The causes of anemia in HIV disease include direct and indirect stem cell inhibition by the virus, increased peripheral destruction of red blood cells, and bone marrow suppression by various opportunistic infections and therapeutic drugs, particularly zidovudine. We compared the efficacy of recombinant human erythropoietin (rHuEPO) therapy in improving the anemia in HIV-infected end-stage renal disease patients (group I) with that in nondiabetic (group II) and diabetic (group III) hemodialysis patients without HIV infection. All three groups of patients were comparable in dialysis prescription and serum iron studies. Iron supplementation was prescribed to all patients, and none received blood transfusions. After 8 weeks of rHuEPO therapy (administered intravenously in a dose of 100 U/kg body weight thrice weekly), the mean increase in hematocrit was similar in all responders (5.8% increase in hematocrit in 23 of 30 HIV patients and 6.7% increase in 24 of 30 non-HIV patients). Response in hematocrit was noted in HIV patients despite the presence of opportunistic infections in 15 and zidovudine administration in 11. Seven HIV-positive patients and six non-HIV patients failed to respond to rHuEPO. Irrespective of the HIV status, the baseline serum EPO levels in patients responding to rHuEPO were significantly lower than those in nonresponders.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Associated Nephropathy↗

Zidovudine is beneficial in human immunodeficiency virus associated nephropathy.

Human immunodeficiency virus associated nephropathy (Hivan) is a distinct renal disease described in patients infected with the human immunodeficiency virus (HIV). Hivan is characterized by a nephrotic syndrome, enlarged kidneys, a histologic finding of focal and segmental glomerulosclerosis, and a very rapid progression to end-stage renal disease (ESRD). No therapeutic intervention has been shown, in a prospective evaluation, to either alter the course of established Hivan or to influence the emergence of Hivan in HIV-infected patients. We conducted a prospective study on 23 consecutively selected patients seen between 1989 and 1992 who were infected with the HIV, 14 (61%) of whom had significant proteinuria (> or = 2+). Percutaneous kidney biopsy was performed in 5 (36%) of the 14 subjects who had significant proteinuria, and histologic examination of the kidney tissue revealed focal and segmental glomerulosclerosis in all 5 cases. Of the 14 subjects with proteinuria, 8 (57%) also had azotemia (serum creatinine level > or = 1.3 mg/dl). Nine (39%) of 23 subjects admitted intravenous drug use, while 9 (39%) of 23 subjects have had an opportunistic infection before enrollment in the study. The known duration of HIV infection before initiation of zidovudine therapy was 10.3 +/- (SD) 8 months. The mean CD4 count before zidovudine therapy was 195.9 +/- 117 (range 21-654) cells/mm3. The mean dose of zidovudine administered was 543 +/- 117 (range 400-800) mg daily for a period of 20.4 +/- 11 (range 6-38) months.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Associated Nephropathy↗

Salvage of clotted jugular vein hemodialysis catheters.

Jugular venous catheters (JVC) provide rapid, vascular access for both emergency and maintenance hemodialysis in both acute and end-stage renal disease. Clotting and occlusion of JVC is a common problem necessitating alternate vascular access. Urokinase will declot 80-90% of central venous catheters; however, recurrence of catheter occlusion is frequent. We successfully employed a guide wire insertion technique to salvage occluded JVC after failed urokinase infusion. In 24 patients JVCs, inserted for either temporary or permanent vascular access, clotted within 6-55 days of initiating hemodialysis. Urokinase (5,000 IU) instilled into both arterial and venous limbs of the catheter had been unsuccessful in restoring patency. In these patients, we inserted a soft-tipped guide wire into both lumina. In 21 of 24 patients (87.5%), guide wire insertion opened the occluded JVC, permitting immediate initiation of hemodialysis. We conclude that for clotted JVC unresponsive to urokinase infusion, guide wire insertion can salvage most catheters thereby facilitating hemodialysis.

Adult↗

Morphological transformation of Syrian hamster embryo cells in primary culture by malachite green correlates well with the evidence for formation of reactive free radicals.

Malachite green (MG) (green crystals with metallic luster and very soluble in water) is highly cytotoxic to mammalian cells and also acts as a liver tumor promoter. In view of its industrial importance and possible exposure to individuals, MG poses a potential environmental health hazard. We have studied the effect of MG on the formation of morphologically transformed colonies using Syrian hamster embryo (SHE) cell transformation assay. MG induced a dose-related increase in the formation of transformed foci, the optimum concentration being 0.05 micrograms/ml. Electron spin resonance (ESR) analysis using 5,5-dimethyl-1-pyrroline N-oxide (DMPO) as a spin-trapping agent showed the formation of reactive free radicals during the in vitro metabolism of MG. The present study suggests a close relationship between the morphological transformation of SHE cells by MG and the possible involvement of reactive free radical formation.

Animals↗

Human immunodeficiency virus (HIV) associated nephropathy.

Patients with HIV infection can manifest a spectrum of potentially reversible forms of acute renal failure and a unique form of nephropathy clinically characterized by nephrotic syndrome, a rapid progression to irreversible uremia in weeks, and a poor prognosis despite maintenance dialysis therapy. Typical histologic features consist of focal and segmental glomerulosclerosis, with some distinct and unusual electron microscopic features in the kidney. HIV-associated nephropathy (HIVAN) is predominantly a disease of young black men; about half are intravenous drug addicts and the remaining half belong to various groups at risk for HIV infection. Evidence points to a viral etiology in the pathogenesis of HIVAN. Currently, no effective forms of therapy are available for HIV-associated nephropathy. It is hoped that the newer antiviral agents given early and for prolonged periods may change the natural history of HIVAN, which at present is a fulminant form of irreversible renal syndrome.

AIDS-Associated Nephropathy↗

The value to the anesthesia-surgical care team of the preoperative cardiac consultation.

A retrospective analysis of 202 consultations for preoperative cardiology evaluation was conducted. The most common problems generating the consultation were: (1) abnormal electrocardiogram, 45 patients; (2) chest pain, 36 patients; (3) history of myocardial infarction, 27 patients; (4) dysrhythmia, 25 patients; and (5) hypertension, 23 patients. The most common diagnoses by the consultants were: (1) arteriosclerotic heart disease, 46 patients; (2) angina, 20 patients; and (3) hypertension, 40 patients. Mitral valve prolapse was the most common valvular disease (18 patients). Of the consultation requests, 108 asked for an evaluation; 79 asked for a "clearance"; 9 did not specifically ask for anything; and 6 asked a highly specific question. Most consultations provided a diagnosis (96%), addressed the problem (80%), and provided logical recommendations (96%). A minority of the consultations "cleared" a patient (28%), provided for follow-up care (41%), or suggested intraoperative monitoring techniques (41%). Out of the 189 patients who eventually had surgery, 137 patients had no change in their preoperative therapy, while 52 patients had a change in preoperative therapy. There was no difference in the incidence of complications between these two groups. An important finding was that 15% of the study group (31 patients) had disease processes (hypertension and angina) that were newly diagnosed by the consultant or felt to be not adequately treated before the consultation. It is concluded that few requesting anesthesiologists and surgeons ask for clarification of a specific problem, while most responses from the cardiology consultants provided necessary information. In addition, the preoperative cardiac consultation was found to identify medical conditions requiring long-term care and follow-up.

Adolescent↗

HIV infection in a high prevalence hemodialysis unit.

The number of intravenous drugs users (IVDUs) developing end-stage renal disease at our institution increased 400% between 1981 and 1987. During this period the total number of IVDUs in our catchment area remained stable and referral patterns to our hospital were unchanged. A serologic, clinical and risk-factor survey for HIV infection was conducted in our maintenance hemodialysis unit with the objective of evaluating the interrelationship between HIV infection and the increasing incidence of renal failure in IVDUs. The risk of nosocomial transmission of HIV in a hemodialysis unit with an expected high prevalence of infection was also investigated. The effect of HIV seropositivity on the clinical course of patients receiving maintenance hemodialysis was evaluated prospectively. Twenty-seven (39%) out of 70 maintenance hemodialysis patients tested were seropositive for HIV. Twenty-three (88%) out of 26 IVDUs receiving dialysis were seropositive for HIV. Despite marked CD4 cell depletion (mean CD4 cell count 225), none of the seropositive patients had AIDS when first evaluated and only one developed AIDS during 12 months of follow-up. None of the dialysis staff members or dialysis patients without HIV risk factors was seropositive for HIV. IVDUs who develop end-stage renal disease appear to have a high rate of infection with HIV. We can expect that the number of HIV-infected dialysis patients will continue to increase. Fortunately, even in a high prevalence hemodialysis unit, the risk of nosocomial transmission of HIV appears to be low.

Cross Infection↗

Renal syndromes in the acquired immunodeficiency syndrome (AIDS): lessons learned from analysis over 5 years.

Renal syndromes associated with the Acquired immunodeficiency syndrome include: potentially reversible acute renal failure, AIDS associated nephropathy which leads to end stage renal disease, and AIDS developing in patients who are being treated by maintenance hemodialysis. The longitudinal study of 95 patients with AIDS and various forms of renal syndrome at two urban institutions indicates that both acute and chronic renal failure is increasing yearly. While some patients with acute renal failure recover renal function and survive for prolonged period, the mortality of dialyzed patients with irreversible renal failure continues to be unsatisfactory. There is a great need for collecting data from high risk areas to analyze the results of maintenance dialysis therapy in patients with AIDS, to assess the economic impact of uremia therapy, and for long-term planning of available resources.

Acquired Immunodeficiency Syndrome↗