Parathyroid hormone as a marker for the differential diagnosis of acute and chronic renal failure

It is often difficult to distinguish acute renal failure clinically from chronic renal failure, especially in patients who do not have records of their medical history. We investigated the magnitude of iPTH increase in ARF and the potential role of iPTH as a marker for differential diagnosis of ARF and CRF in new patients referred to our renal unit. We prospectively analyzed 122 (ARF n = 64, CRF n = 58) patients referred to our renal unit with serum creatinine higher than 2 mg/dL. ROC curve analysis was performed to investigate role of iPTH for differentiating ARF from CRF. The sensitivity, specificity, and positive predictive value of iPTH in discrimination of ARF and CRF were calculated. There was no statistically significant difference regarding the means of age, sex distribution, and serum chemistry between patients with ARF or CRF. But serum iPTH (p < 0.0001) levels were lower in patients with ARF than in those with CRF. A cutoff, set at 170 pg/mL for iPTH to discriminate patients with CRF, yielded a sensitivity of 88% and a specificity of 89%. This study confirms that the iPTH measurement is of clinical value in differentiating acute from chronic renal failure.     

Parathyroid Hormone as a Marker for the Differential Diagnosis of Acute and Chronic Renal Failure

It is often difficult to distinguish acute renal failure clinically from chronic renal failure, especially in patients who do not have records of their medical history. We investigated the magnitude of iPTH increase in ARF and the potential role of iPTH as a marker for differential diagnosis of ARF and CRF in new patients referred to our renal unit. We prospectively analyzed 122 (ARF n?=?64, CRF n?=?58) patients referred to our renal unit with serum creatinine higher than 2 mg/dL. ROC curve analysis was performed to investigate role of iPTH for differentiating ARF from CRF. The sensitivity, specificity, and positive predictive value of iPTH in discrimination of ARF and CRF were calculated. There was no statistically significant difference regarding the means of age, sex distribution, and serum chemistry between patients with ARF or CRF. But serum iPTH (p < 0.0001) levels were lower in patients with ARF than in those with CRF. A cutoff, set at 170pg/mL for iPTH to discriminate patients with CRF, yielded a sensitivity of 88% and a specificity of 89%. This study confirms that the iPTH measurement is of clinical value in differentiating acute from chronic renal failure.     

Plasma leptin concentration in patients with acute renal failure

BACKGROUND: Acute renal failure (ARF) is characterized by impaired excretory, endocrine, homeostatic and metabolic function of the kidneys. It is well-known that leptin is an adipose-derived polypeptide hormone which is predominantly biodegraded by the kidneys. Therefore, plasma leptin concentration is increased in chronic renal failure (CRF). However, its' concentrations in patients with ARF were not investigated until now. The aim of the present study was to evaluate plasma leptin concentration in patients with ARF. PATIENTS AND METHODS: 27 patients with ARF (age 44 +/- 4 years, BMI 26.0 +/- 0.9 kg/m2, means +/- SEM, 17 patients 15 M, 2 F recovered kidney function and 10 patients 7 M, 3 F died during the anuric phase), 27 hemodialysis patients (22 M, 5 F; age 45 +/- 2 years; BMI 26.2 +/- 0.8 kg/m2) with chronic renal failure (CRF) and 27 healthy subjects (HS) (22 M, 5 F; age 42 +/- 3 years; BMI 25.9 +/- 0.6 kg/m2) were examined. In patients with ARF, blood samples for plasma leptin and routinely assessed biochemical parameters were withdrawn before the first HD session (I), and in patients who survived a second time 5 days later during the anuric/oliguric phase (II), and a third one during the polyuric phase before discharge of the patient from hospital (III). In patients with CRF all examined parameters were estimated only once before a subsequent HD session. RESULTS: Patients with ARF (before the first HD session) and CRF did not differ significantly with respect to BMI, serum creatinine and blood hydrogen ion concentrations. Plasma leptin level in patients with ARF before the first HD session was similar to values obtained in HS, but significantly lower (p < 0.01) than in patients with CRF (2.5 (1.9 - 8.2) vs. 3.4 (2.5 - 8.3) vs. 8.4 (2.9 - 16.9) ng/ml in ARF, HS and CRF, respectively). There was no significant difference in leptinemia between patients with ARF who survived and who died. In patients with ARF who survived, improvement ofrenal function was accompanied by a slightly (not significant) declining tendency in plasma leptin concentration (5.6 +/- 2.2 vs. 4.8 +/- 1.7 vs. 4.5 +/- 1.3 ng/ml; I, II, III phases of ARF, respectively). CONCLUSIONS: In contrast to hemodialysis patients with chronic renal failure, patients with acute renal failure are characterized by normal plasma leptin concentration. Thus, difference in leptinemia between patients with chronic and acute renal failure seems to be due to preservation of large amounts of active renal parenchyma in ARF patients.     

Validation of Liano score in acute renal failure: a prospective study in Indian patients

Aim  To validate Liano score as a prognostic scoring system in acute renal failure (ARF): a prospective study in Indian patients. Patients and methods  Prospective study including 100 patients over a period of 1 year, from March 2006 to July 2007. Inclusion criteria were patients with no previous renal disease or any systemic disease known to affect the kidney and who presented with acute rise (hours to days) in serum creatinine. Exclusion criteria were patients with preexisting chronic renal failure, age younger than 12 years and ultrasound of the abdomen showing contracted kidneys. Results and conclusions  In this study there were 68 males and 32 females. Peak incidence by age was in the fifth decade. There was no increased mortality in any age group (p = 0.278). A total of 19 patients had pre-renal ARF, 74 patients had intrinsic ARF, of which 46 were acute tubular necrosis (ATN); 7 patients had obstructive ARF. A total of 21 patients had Liano score greater than 0.9, of which 18 patients died and 3 were discharged against medical advice in a critical condition (and died later at home). Calculated sensitivity was 62.1%, specificity was 100% and positive predictive value was 100%. Sensitivity and specificity when calculated separately for intrinsic renal ARF (after excluding post renal ARF) were 60.7% and 100%, respectively. There was statistically significant correlation between Liano score and mortality (p < 0.001).     

The effects of acute renal failure on long-term renal function

The relationship between acute renal failure (ARF) and long-term renal function remains unknown. We therefore undertook a study of patients at the Baltimore VA Hospital to examine the effects of a bout of acute renal injury on long-term renal function. We retrospectively reviewed the relationship between serum creatinine and time of observation for 6058 individuals who had values greater than 1.4 mg/dL in any two consecutive years. Individuals were stratified according to total years of observation with a minimum of two years. Severity of acute renal injury was divided into mild, moderate, and severe with elevations in baseline creatinine of < 50%, 50-300% and > 300% respectively. Sporadic elevations in creatinine were evident in 8-15% of the population. There were a total of 1328 episodes of acute renal failure in 916 patients that were suitable for analysis. Mild ARF on a substrate of normal or mildly abnormal renal function resolved without long-term sequelae. Moderate and severe ARF occurred more frequently on a background of reduced renal function but baseline function was retained in at least 60% of patients. We conclude that ARF is more frequent in patients with chronic kidney disease but it is not invariably associated with an accelerated course to end-stage renal disease or death. Overall, the majority of ARF events resolved without adverse long-term effects suggesting appropriate management in the majority of instances.     

The Effects of Acute Renal Failure on Long-Term Renal Function

The relationship between acute renal failure (ARF) and long-term renal function remains unknown. We therefore undertook a study of patients at the Baltimore VA Hospital to examine the effects of a bout of acute renal injury on long-term renal function. We retrospectively reviewed the relationship between serum creatinine and time of observation for 6058 individuals who had values greater than 1.4 mg/dL in any two consecutive years. Individuals were stratified according to total years of observation with a minimum of two years. Severity of acute renal injury was divided into mild, moderate, and severe with elevations in baseline creatinine of <50%, 50–300% and >300% respectively. Sporadic elevations in creatinine were evident in 8–15% of the population. There were a total of 1328 episodes of acute renal failure in 916 patients that were suitable for analysis. Mild ARF on a substrate of normal or mildly abnormal renal function resolved without long-term sequelae. Moderate and severe ARF occurred more frequently on a background of reduced renal function but baseline function was retained in at least 60% of patients. We conclude that ARF is more frequent in patients with chronic kidney disease but it is not invariably associated with an accelerated course to end-stage renal disease or death. Overall, the majority of ARF events resolved without adverse long-term effects suggesting appropriate management in the majority of instances.     

Acute Renal Failure Complicating Severe Acute Pancreatitis

The records of 563 patients admitted to the hospital with diagnosis of acute pancreatitis have been studied retrospectively. The aim of the study was to investigate the prevalence of acute renal failure (ARF) in these patients, and to evaluate the most important risk factors for ARF development and mortality. The prevalence of ARF in studied population was 14%, but only 3.8% of ARF patients with acute pancreatitis had isolated renal failure. Other patients had additional failure of other organ systems, 68.4% of whom had multiorgan failure (MOF) before the onset of ARF. In only 8.9% of ARF patients was the renal system the first organ system to fail. Patients with ARF were significantly older, had more preexisting chronic diseases (including chronic renal failure), usually had MOF, and local pancreatic complications relative to these in the group with normal renal function. The development of ARF was directly influenced by severity of acute pancreatitis. The mortality rate in ARF patients was 74.7%, compared to an 7.4% mortality of patients with acute pancreatitis and normal renal function. Preexisting chronic disease, the presence of MOF and their number, local pancreatic complications, and older age of the patients increased mortality in ARF patients. The prognosis of patients with oliguric ARF requiring renal replacement therapy was extremely poor, indicating the importance of prevention of ARF in the patients with acute pancreatitis.     

Acute and chronic renal failure in liver transplantation

We have performed a retrospective review of the incidence and etiologies of acute renal failure (ARF) in 105 adult patients receiving liver transplants. The prevalence of chronic renal failure was also determined. ARF occurred in 94.2% of these patients. Acute tubular necrosis was the leading cause of ARF and was associated with the highest mortality. Factors associated with increased mortality included: (1) peak serum creatinine greater than 3 mg/dl, (2) multiple liver transplants and (3) the need for dialysis. Pretransplant renal failure did not increase mortality. Chronic renal failure developed in 83% of patients at latest follow-up (mean: 30.5 +/- 7.9 months).     

Acute renal failure in patients with acute pancreatitis: prevalence, risk factors, and outcome

A total of 267 consecutive patients presenting with acute pancreatitiswere studied restrospectively. We analysed the collected datato determine the prevalence of acute renal failure (ARF), andfactors significantly predisposing to its occurrence and outcome.The prevalence of ARF in our patients was 16%. Only 2% had isolatedARF. Seventy-three percent of patients with additional organsystem failure suffered ARF after the onset of other organ failure.The number of organ system failure was significantly greaterbefore, compared to after, the development of ARF. Using multiplelogistic regression we found that pre-existing chronic diseaseand cardiovascular and haematological failure were independentrisk factors positively related to the development of ARF, whereassystemic infection was not. Overall mortality from ARF was 81%.Chronic disease, local complications and the presence of additionalorgan system failure and their number significantly increasedmortality in ARF patients. No patients requiring renal replacementtherapy survived. ARF is a common complication of severe acute pancreatitis, butoccurs late in the disease course, and mostly preceded by otherorgan system failure. The prognosis of patients with ARF isextremely poor, indicating that more emphasis should be placedon prevention of ARF.     

一氧化氮与大鼠缺血性急性肾衰竭关系的实验研究

目的 研究一氧化氮（ＮＯ）在缺血性急性肾衰竭病理过程中的作用。方法 通过夹闭大鼠双侧肾蒂４５分钟后再松夹复制出急性肾衰（ＡＲＦ）模型,各组在松夹后分别静滴生理盐水,Ｌ－精氨酸,Ｄ－精氨酸,Ｎ－硝基－Ｌ－精氨酸（ＮＬＡ）。结果 与盐水对照组相比,Ｌ－精氨酸组菊糖清除率和再灌注早期的尿流率增高（Ｐ〈０．０５）,尿钠排泄分数下降（Ｐ〈０．０５）,肾病理损害也较轻（Ｐ〈０．０５）,ＮＬＡ虽升高血压（Ｐ〈０     

Renal failure in the ICU: comparison of the impact of acute renal failure and end-stage renal disease on ICU outcomes

BACKGROUND: Acute renal failure (ARF) is associated with a persistent high mortality in critically ill patients in intensive care units (ICUs). Most studies to date have focused on patients with established, intrinsic ARF or relatively severe ARF due to multiple factors. None have examined outcomes of dialysis-dependent chronic renal failure [end-stage renal disease (ESRD)] patients in the ICU. We examined the incidence and outcomes of ARF in the ICU using a standard definition and compared these to outcomes of ICU patients with either ESRD or no renal failure. We sought to determine the impact of renal dysfunction and/or loss of organ function on outcome. METHODS: We prospectively scored 1530 admissions to eight ICUs over a 10-month period for illness severity at ICU admission using the Acute Physiological and Chronic Health Evaluation (APACHE III) evaluation tool. Patients were defined as having ARF based on the definition of Hou et al (Am J Med 74:243-248,1983) designed to detect significant measurable declines in renal function based on serum creatinine. ESRD patients were identified as being chronically dialysis-dependent prior to ICU admission and the remainder had no renal failure. Clinical characteristics at ICU admission and ICU and hospital outcomes were compared between the three groups. RESULTS: We identified 254 cases of ARF, 57 cases of ESRD and 1219 cases of no renal failure for an incidence of ARF of 17%. Roughly half the ARF patients had ARF at ICU admission and the remainder developed ARF during their ICU stay. Only 11% of ARF patients required dialysis support. ARF patients had significantly higher acute illness severity scores than those with no renal failure, whereas patients with ESRD had intermediate severity scores. ICU mortality was 23% for patients with ARF, 11% for those with ESRD, and 5% for those with no renal failure. There was no difference in outcome between patients who had ARF at ICU admission and those who developed ARF in the ICU. Patients with ARF severe enough to require dialysis had a mortality of 57%. APACHE III predicted outcome very well in patients with no renal failure and patients with ARF at the time of scoring but underpredicted mortality in those who developed ARF after ICU admission and overestimated mortality in patients with ESRD. CONCLUSIONS: ARF is common in ICU patients and has a persistent negative impact on outcomes, although the majority of ARF is not severe enough to require dialysis support. The mortality of patients with ARF from all causes is almost exactly similar to that noted using the same criteria two decades ago. More profound ARF requiring dialysis continues to have an even greater mortality. Nevertheless, acute declines in renal function are associated with a mortality that is not well explained simply by loss of organ function. The majority of ARF patients who did not require dialysis still had a considerably higher mortality than the ESRD patients, all of whom required dialysis; while ARF patients who did require dialysis had a much higher morality than ESRD patients. APACHE III performs well and captures the mortality of patients with ARF at the time of scoring. Development of ARF after scoring has a profound effect on standardized mortality. We were unable to identify a unique mortality associated with ARF, but the presence of measurable renal insufficiency continues to be a sensitive marker for poor outcome.     

Successful transplantation of kidneys from deceased donors with acute renal failure: Three-year results

BACKGROUND: Kidneys from deceased donors with acute renal failure (ARF) are generally not accepted for transplantation because of the expected poor outcome. This prospective study examined the utilization of kidneys from donors with ARF for transplantation and the outcomes. METHODS: Fifty-five kidneys from donors with ARF were transplanted. The outcome was compared with concurrent and matched 55 recipients of standard criteria donor (SCD) kidneys and 55 expanded criteria donor (ECD) kidneys. ARF kidneys were accepted from donors aged <50 years, a negative history for kidney disease, and a negative pretransplant biopsy for chronic structural changes. The immunosuppression was similar in all three groups. The outcome measurements included three-year patient and graft survival, biopsy-proven acute rejection (BPAR), subclinical acute rejection (SCAR), and chronic allograft nephropathy (CAN), serum creatinine, and creatinine clearance. RESULTS: Three-year patient and graft survival was 90% and 90% in ARF group, 100% and 89% in SCD group and 83% and 66% in ECD group. BPAR and SCAR were comparable in the groups but CAN was significantly higher in ECD group. Mean serum creatinine levels were 1.9+/-1.1, 1.9+/-0.9, and 2.2+/-1.3 mg/dl and mean creatinine clearances were 66+/-15, 68+/-14, and 58+/-10 mls/minute in ARF, SCD, and ECD groups, respectively (SCD and ARF vs. ECD P = 0.04). CONCLUSIONS: Transplantation of kidneys from selected deceased donors with ARF provides comparable survival and function compared to kidneys from non-ARF donors and may be considered for transplantation to expand the donor pool to overcome the current acute shortage of kidneys.     

Acute and chronic renal disease in hospitalized AIDS patients

We performed a retrospective chart analysis on 449 AIDS patients admitted to Bellevue Hospital Center from 1983-1986 to characterize the etiologies and clinical course of acute renal failure (ARF) and to define the incidence and clinical course of AIDS-associated nephropathy (AAN) in an unselected hospitalized AIDS population. Defining ARF as a rise from baseline serum creatinine of at least 2.0 mg%, we found 88 cases (a prevalence of almost 20%) or 14.5 cases per 100 admissions. Volume depletion was the most common etiology and was as severe a cause of ARF as other etiologies. There were 21 cases of ARF in 17 patients with a peak serum creatinine greater than or equal to 6.0 mg%. Volume depletion accounted for 7/21 of these cases. Baseline renal insufficiency existed in 9/17 patients (12/21 cases) and volume depletion was the cause of ARF in 3 of these cases. Only 4 cases required dialysis. There were 34 patients (prevalence of 7.6% or 3.0 cases per 100 patient-years) with otherwise unexplained chronic renal insufficiency and/or persistent qualitative or quantitative proteinuria and thus were defined on clinical grounds to have AIDS-associated nephropathy. Thirty-two of these patients (94%) had evidence of AAN at or within 1 year of presentation. Eleven patients (32%) reached ESRD (serum creatinine greater than or equal to 6.0 mg%); 9 patients did so within 1 year of presentation and 3 required dialysis. In those with adequate follow-up (9 cases), the mean survival from time of ESRD was 25.5 days and all cases died within 6 months of reaching ESRD.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ultrasonographic study on kidneys in patients with chronic renal failure. Part I. Ultrasonic measurement of renal size and analysis of renal ultrasonotomograms

Ultrasonograms of 546 kidneys were obtained in 280 patients undergoing chronic dialysis. Dialysed kidneys could be detected in 529 of the 546 kidneys (96.9%) by ultrasonic examination. The ultrasonic diagnoses on dialysed kidneys were contracted kidney in 313 kidneys (59.2%) and acquired cystic disease of the kidney in 107 kidneys (20.2%). Ultrasonic measurement of the size of kidney (length and thickness) revealed that the kidneys in patients with chronic renal failure were much smaller than normal ones. But the kidneys in patients undergoing dialysis for more than 8 years gradually increased in size with incidence of acquired renal cysts. The kidneys in patients with diabetic nephropathy were greater in length and thickness than those with chronic glomerulonephritis. Sonographic features of dialysed kidneys were unclear renal imaging, unidentified central echoes, cortico-medulla + border and increased parenchymal echogenicity. Irregularity of the renal contour had a tendency to increase in number with incidence of cysts in long-term dialysis patients. The ultrasonograms of the kidneys with diabetic nephropathy showed fewer changes than normal ones. No major complication of the kidney was detected in the present study. However, two retroperitoneal hematomas and one renal cell carcinoma developed within two years after this examination. We believe that regular screening of the kidneys by ultrasonic examination is mandatory in patients on chronic dialysis for early diagnosis and treatment of these complications.     

Importance of serum ferritin levels in patients with renal failure

Study results on acute phase reactants of renal failure patients are controversial. In this study, we enrolled 39 patients and divided them into 2 groups: acute renal failure (ARF), and chronic renal failure (CRF) patients. As opposed to CRF patients, the patients with ARF had higher serum ferritin levels that were independent of anemia parameters and other acute phase reactants.     

The safety of gadolinium in patients with stage 3 and 4 renal failure.

BACKGROUND: Although there is a well-documented risk of acute renal failure (ARF) with the iodinated contrast agents, intravenous gadolinium-based contrast agents are considered non-nephrotoxic and have been widely used for magnetic resonance imaging (MRI). However, debate continues regarding the safety issue of gadolinium, especially in patients with kidney failure. Therefore, we aimed to evaluate the safety of gadolinium in patients with stage 3 and 4 renal failure as well as risk factors for nephrotoxicity. METHOD: We retrospectively analysed 473 patients with chronic renal failure who underwent angiographic MRI procedures in our centre from February 1999 to March 2005 in whom gadolinium was used as the sole contrast agent at a dose of 0.2 ml/kg. Among them, 91 patients with stage 3 or 4 renal failure according to K/DOQI definition, who had available data in their files, were enrolled in the study. The ARF was defined as an increase of at least 0.5 mg/dl in serum creatinine level over baseline after using gadolinium. RESULTS: Eleven of 91 (52 males, 39 females; median age 59 years; median estimated glomerular filtration rate (eGFR) 33 ml/min/1.73 m2) patients developed ARF (12.1%). The median eGFR was lower in patients with ARF than in those who did not develop ARF. The risk factors for ARF were baseline eGFR, older age, diabetic nephropathy and low baseline haemoglobin and albumin levels. Baseline eGFR and diabetic nephropathy were determined as the independent risk factors in regression analysis. CONCLUSIONS: An ARF can occur after gadolinium-based contrast agents in patients with moderate to severe chronic renal failure. Risk factors for ARF after gadolinium toxicity include diabetic nephropathy and low GFR.     

Acute renal failure in falciparum malaria: clinical characteristics, demonstration of oxidative stress, and prognostication

In this prospective study, we aimed to assess the clinical characteristics of acute renal failure (ARF), determine oxidative stress, as well as to predict the outcome in patients with severe falciparum malaria (FM). The study included a total of 75 subjects; there were 25 adult patients with acute severe FM and ARF, 25 adult patients with uncomplicated FM without ARF, and 25 age- and sex-matched healthy subjects who served as controls. In patients with severe FM and ARF (n = 25), renal failure was non-oliguric in 28% and oliguric in 72%. The average duration of renal failure was 10.53 ± 4.0 days. Sixty percent recovered and 40% died. All patients with non-oliguric presentation recovered. The mean serum malondialdehyde (MDA) levels were 0.82 ± 0.43 μmol/L, 2.97 ± 1.11 μmol/L, and 6.86 ± 2.62 μmol/L, respectively, in healthy controls, in patients with uncomplicated FM, and in those with severe FM with ARF. The Acute Physiology Age and Chronic Health Evaluation II (APACHE II) score, Sequential Organ Failure Assessment (SOFA) score, and the Acute Tubular Necrosis-Individual Severity Index (ATN-ISI) score were all significantly higher in the expired group (19 ± 5.49) when compared to the survivor group (14.4 ± 3.15) (P = 0.014). Kaplan-Meier survival analysis showed that survival was low in patients with delayed hospitalization and longer duration of symptoms. Also, we observed a high occurrence of acute respiratory distress syndrome and central nervous system involvement among the patients who expired.     

Acute renal failure following bone marrow transplantation: a retrospective study of 272 patients

To assess the incidence, risk factors, and course of acute renal failure (ARF) following bone marrow transplantation (BMT), a retrospective analysis of 272 patients receiving transplants at the Fred Hutchinson Cancer Research Center during 1986 was undertaken. The patients were divided into three groups: group 1, hemodialysis requiring ARF; group 2, mild renal insufficiency (doubling of serum creatinine, Scr, but no dialysis); group 3, relatively normal post-BMT renal function (no doubling of Scr). Fifty-three percent of patients at least doubled their Scr (Groups 1 and 2), and 24% required dialysis. The degree of renal functional impairment had a dramatic impact on patient mortality rates (84%, 37%, and 17% in groups 1, 2, and 3, respectively). Jaundice (bilirubin greater than or equal to 2.0 mg/dL), weight gain (greater than or equal to 2.0 kg), amphotericin B use, and a pretransplant Scr greater than or equal to 0.7 mg/dL were independently associated with the subsequent development of dialysis-requiring ARF (P less than 0.001; relative risks, 3.0 to 7.7). Neither aminoglycoside/vancomycin/cyclosporine A use nor acute graft v host disease correlated with the development of ARF. A mismatched graft was a significant risk factor for ARF by univariate but not by multivariate analysis. Within 48 hours before doubling the Scr, 63% of group 1 patients had positive blood cultures and 39% developed hypotension. Of the 26 group 1 patients who had urine Na concentrations measured, 85% had values less than or equal to 40 mEq/L. Autopsy kidney specimens provided no clear explanation for ARF in the vast majority of patients in group 1.(ABSTRACT TRUNCATED AT 250 WORDS)     

Histological features of acute tubular necrosis in native kidneys and long-term renal function

There are few studies on the relationship between the morphology of acute tubular necrosis (ATN) in native kidneys and late functional recovery. Eighteen patients with acute renal failure (ARF) who had undergone renal biopsy were studied. All had the histological diagnosis of ATN and were followed for at least six months. Clinical characteristics of ARF were analyzed, and histological features were semi-quantitatively evaluated (tubular atrophy, interstitial inflammatory infiltrate, interstitial fibrosis, and ATN). According to the maximal GFR achieved during the follow-up, patients were divided into two groups: complete recovery (GFR >or= 90 mL/min/1.73 m(2)) and partial recovery (GFR < 90 mL/min/1.73 m(2)). Only 39% of the patients achieved complete recovery. Patients with partial recovery achieved their maximal GFR (63 +/- 9 mL/min/1.73 m(2)) 37 +/- 14 months after ARF, a period of time similar to those patients with complete recovery (i.e., 54 +/- 22 months). Patients with partial recovery had more severe ARF: oliguria was more frequent (90 versus 17%, p < 0.01), and they had higher peak creatinine (13.85 +/- 1.12 versus 8.95 +/- 1.30 mg/dL, p = 0.01), and longer hospitalization (45 +/- 7 versus 20 +/- 4 days, p = 0.03). No single histological parameter was associated with partial recovery, but the sum of all was when expressed as an injury index [4.00 (2.73-5.45) versus 2.00 (1.25-3.31), p < 0.05]. In conclusion, among patients with atypical ATN course, those with more severe ARF and tubule-interstitial lesions are more prone to partial recovery.     

A trial of thyroxine in acute renal failure

A trial of thyroxine in acute renal failure. BACKGROUND: Acute renal failure (ARF) remains a serious medical problem with a high mortality rate. Efforts to shorten the course of ARF might reduce this mortality. Since thyroxine has been shown in experimental models to shorten the course of ARF, we designed a trial to determine if a defined course of thyroxine would alter the course or change the mortality of clinical ARF. METHODS: A prospective, randomized, placebo-controlled, double-blind trial of thyroxine was carried out in patients with ARF. End points were the percentage requiring dialysis, the percentage recovering renal function, time to recovery, and mortality. RESULTS: Fifty-nine patients were randomized to receive either thyroxine or placebo. The groups were well matched in terms of basal and entry creatinines, age, sex, APACHE II scores at entry, and percentage oliguric. Baseline thyroid functions, including T3, T4, rT3, and thyroid stimulating hormone (TSH) levels, were equal between the two groups and typical of patients with euthyroid sick syndrome. Thyroxine resulted in a progressive and sustained suppression of TSH levels in the treated group, but had no effect on any measure of ARF severity. Mortality was higher in the thyroxine group than the control group (43 vs. 13%) and correlated with suppression of TSH. CONCLUSIONS: In contrast to the beneficial effects seen in experimental ARF, thyroxine has no effect on the course of clinical ARF and could have a negative effect on outcome through prolonged suppression of TSH. Critically ill euthyroid sick patients should not be replaced with thyroid hormone.