USE OF THE ARTIFICIAL KIDNEY—Its Place in the Treatment of Acute Renal Failure

Of 57 patients with severe, but potentially reversible, acute renal failure who were observed during a recent four-year period, some had dialysis with an artificial kidney and some did not.Twenty survived with the standard “conservative” management alone; 19 survived with a combination of “conservative” and “intensive” (that is, artificial kidney) treatment; 18 patients died.One error that was made in the management of all 18 patients who died, was excessive delay in the use of the artificial kidney.Hemodialysis should be used whenever serious electrolyte abnormality exists, whenever the blood urea nitrogen exceeds 150 mg. per 100 cc. or whenever clinical signs of uremia first appear. One or more of these indications will usually, but not always, become evident between the fifth and the eighth day of virtual anuria.     

Incidence of advanced chronic renal failure and the need for end stage renal replacement treatment.

OBJECTIVE--To determine the age related incidence of advanced chronic renal failure in two areas of England. DESIGN--Prospective study of patients newly identified as having advanced chronic renal failure within a two year period; subsequent monitoring of patients'' clinical course for a further 26 months. SETTING--Devon and Blackburn. SUBJECTS--Those patients in a population of 708,997 who developed advanced chronic renal failure (serum creatinine concentration greater than 500 mumol/l) for the first time during a two year period. MAIN OUTCOME MEASURES AND RESULTS--210 Patients (148 per million population per year) developed advanced chronic renal failure, 117 (51%) of whom were over 70. The age related incidence rose from 58 per million per year in those aged 20-49 to 588 per million per year in those aged 80 or over. Only 54% (113) of patients were referred to a nephrologist; 120 patients (57%) needed dialysis or died within three months of presenting without receiving dialysis, and 187 (89%) died or needed dialysis within three years. After those unsuitable for further treatment had been excluded, 78 patients per million population per year aged under 80 needed to start long term renal replacement treatment. CONCLUSIONS--Many patients suitable for renal replacement treatment are still not referred for nephrological opinion and are denied treatment. If the treatment rate in the United Kingdom rose from the 1988 rate of 55.1 per million per year to 78 per million per year then the number of patients receiving treatment would rise to about 800 per million. This is double the present number and has considerable but predictable resource implications for the NHS.     

Incidence of severe acute renal failure in adults: results of a community based study.

OBJECTIVE--To determine the age related incidence of severe acute renal failure in adults in two health districts in England. DESIGN--Prospective study of patients identified as having severe acute renal failure within a two year period; subsequent monitoring of outcome for a further two years. SETTING--Two health districts in Devon. SUBJECTS--Those adults in a population of 444,971 who developed severe acute renal failure (serum creatinine concentration > 500 mumol/l) for the first time during two years, with subsequent fall of the serum creatinine concentration below the index value. MAIN OUTCOME MEASURES AND RESULTS--125 adults (140 per million total population yearly, 172 per million adults) developed severe acute renal failure, of whom 90 (72%) were over 70. Age related incidence rose from 17 per million yearly in adults under 50 to 949 per million yearly in the 80-89 age groups. In 31 patients (25%) the cause was prostatic disease, which was related to a good prognosis (84% (26) alive at three months). Overall survival was 54% (67) at three months and 34% (42) at two years and was not significantly age related. 18 per million total population yearly (22 per million adult population) received acute dialysis. Referral rate for specialised opinion was 51 per million total population yearly with an estimated appropriate referral rate of 70 per million per year. CONCLUSIONS--The incidence of severe acute renal failure in the community is at least twice as high as the incidence reported from renal unit based studies. Prostatic disease, a preventable and treatable problem, is the most common cause. Survival figures indicate that age alone should not be a bar to specialist referral or treatment.     

Acute Renal Failure and Open Heart Surgery

A retrospective study of 428 open heart operations showed the incidence of mild and severe renal failure to be 26% and 4·7% respectively. The mortality rate was 38% in the mild cases and 70% in the severe cases. Only half of the patients whose death was associated with renal failure showed macroscopic or microscopic renal lesions at necropsy. The patients who developed renal impairment had significantly higher mean preoperative blood urea (40 mg/100 ml) than the non-renal-failure cases (33 mg/100 ml). Periods of perfusion over 60 minutes, mean perfusion pressures below 80 mm Hg, and multiple valve replacement operations also increased the incidence of renal failure. There was no statistical correlation between the age of individual patients, the degree of cooling, and postoperative blood urea values. There was no evidence to suggest that frusemide or mannitol separately or together influenced the development of renal failure. Peritoneal dialysis was preferred for initial treatment of patients with severe renal failure, and haemodialysis was required only in special cases.     

Nephrotic Syndrome Due to Primary Renal Disease in Adults: I. Survey of Incidence in South-east England

In a prospective survey of the nephritic syndrome due to primary renal disease in adult patients in the South-east Metropolitan Region of England 50 patients were seen in a two-year period—a minimum annual incidence of 9·0 new cases per million adult population. The frequency distribution of the three main histological groups was “minimal change” 30%, membranous nephropathy 12%, and proliferative glomerulonephritis 58%. The higher proportion of patients with minimal histological change compared with that found in most previously published series may be explained by the avoidance of selection of patients for inclusion. The much lower incidence of membranous nephropathy probably reflects the use of stricter histological criteria for this diagnosis.     

NONOBSTRUCTIVE OLIGURIA—Differential Diagnosis

A review is presented of ten years'' experience with the differential diagnosis of oliguria, utilizing the standard tests of renal function with the addition of the phenolsulfonphthalein excretion and urinary chloride measurements. The histories of 60 patients seen in consultation because of 24-hour urinary volume of less than 400 ml were studied in order to clarify the value of these tests. Particular attention was given to the postoperative “dilution state,” the oliguria of which tends to mimic that of “acute tubular necrosis.”In only 25 per cent of the 60 cases was “acute tubular necrosis” responsible for the oliguria. In the remaining 75 per cent of patients, oliguria was due either to the effects of simple dehydration without tubular damage, or to tubular dysfunction on a physiologic rather than an organic basis. Thus, three out of four patients with oliguria required aggressive and specific fluid-electrolyte therapy, often with the intensive use of potassium. One out of four required the opposite in therapy—controlled dehydration without added potassium and, on occasion, peritoneal or extracorporeal dialysis, in order to allow six to ten days for tubular repair.     

Volatile Organic Compounds in Uremia

Background

Although “uremic fetor” has long been felt to be diagnostic of renal failure, the compounds exhaled in uremia remain largely unknown so far. The present work investigates whether breath analysis by ion mobility spectrometry can be used for the identification of volatile organic compounds retained in uremia.

Methods

Breath analysis was performed in 28 adults with an eGFR ≥60 ml/min per 1.73 m², 26 adults with chronic renal failure corresponding to an eGFR of 10–59 ml/min per 1.73 m², and 28 adults with end-stage renal disease (ESRD) before and after a hemodialysis session. Breath analysis was performed by ion mobility spectrometryafter gas-chromatographic preseparation. Identification of the compounds of interest was performed by thermal desorption gas chromatography/mass spectrometry.

Results

Breath analyses revealed significant differences in the spectra of patients with and without renal failure. Thirteen compounds were chosen for further evaluation. Some compounds including hydroxyacetone, 3-hydroxy-2-butanone and ammonia accumulated with decreasing renal function and were eliminated by dialysis. The concentrations of these compounds allowed a significant differentiation between healthy, chronic renal failure with an eGFR of 10–59 ml/min, and ESRD (p<0.05 each). Other compounds including 4-heptanal, 4-heptanone, and 2-heptanone preferentially or exclusively occurred in patients undergoing hemodialysis.

Conclusion

Impairment of renal function induces a characteristic fingerprint of volatile compounds in the breath. The technique of ion mobility spectrometry can be used for the identification of lipophilic uremic retention molecules.     

Medical Students in Canadian Universities: Report of Statistics, 1966-67

Enrolment in the 13 Canadian medical schools in 1966-67 reached a new high of 4230, an increase of 5.1% over 1965-66. The percentage of women among medical students (12.1%) was close to that of the preceding three years. There has been a levelling off in the decline of students from outside Canada in 1966-67, when 9.5% of medical students were non-Canadian. The decline had been primarily in the number of American students, which continues. The number of students from Commonwealth countries has shown a steady increase during the eight-year period under review; in 1966-67, they make up nearly one-half of all non-Canadian students. It was noted that 18.5% of overseas students came to Canada under governmental or intergovernmental sponsorship. Of the Canadian students, 94% came from the “home” provinces of the medical schools.     

Applicants to Canadian Medical Schools for 1966-67

An examination of applicants to Canadian medical schools for 1966-67 revealed that 4534 applications were received for the approximately 974 available places. The number of Canadian applications was 2866 and these were made by 1815 individual applicants, an increase of 48 over 1965-66. United States applicants declined from 1143 to 1013.Evaluations made by the schools concerning the acceptability of the Canadian applicants disclosed that 55 applicants who rated as “acceptable” by one or more schools failed to gain admission to any medical school in 1966-67 (as compared to 36 in 1965-66). However, of those applicants who did find a place 76 were evaluated as “marginal” or “unacceptable”, while another 126 were rated as “acceptable” by one school but “marginal” and/or “acceptable” by one or more other schools.These results were interpreted to imply that the Canadian medical schools were still experiencing difficulty in attracting well-qualified applicants for study in medicine.     

Tissue Matching and Early Rejection of Cadaveric-Donor Renal Allografts: The Importance of Unidentified Donor Antigens

Tissue typing has been reviewed in a series of 100 technically successful cadaveric-donor kidney grafts. The criterion of transplant failure was immunological rejection causing total loss of function within three months of operation.No significant correlation was observed between matching grade and graft failure due to early acute rejection. This is attributed to the failure to detect at least one “LA” or “4” antigen (as defined in our laboratory), representing a potential incompatibility, in 89% of the grafts, and in the remaining 11% to the lack of an available recipient with identical “LA” and “4” typing. Undetected antigens on the donor are usually incompatible, and probably these incompatibilities unfavourably influence early graft survival.If the results of cadaveric-donor renal transplantation are to equal those of transplantation from well-matched living related donors it will be necessary to type with sera which can recognize individually all HL-A antigens, including those not yet identified, and to create an international pool of over 1,000 potential recipients.     

The Probability of Death Following a Fracture of the Hip

All patients 45 years of age and over admitted with fractures of the hip to hospitals in the Atlantic Health Region of Nova Scotia were followed up over a two-year period. Actuarial methods were used to estimate survivorship from the date of fracture in 202 patients.Over-all, it was estimated that only 63.8% would be alive by one year post-fracture. This is 70% of the survival rate expected in the general population of corresponding age and sex. The period of greatest mortality was within the first 12 weeks. Patients surviving to one year could be considered “cured”, for after that their survivorship was at least as favourable as that of the “normal” population.Mortality was greatest in males in those 75 years of age and over and especially in patients who were relatively immobilized prior to their fracture. In this “dependent” group the relative survival ratio at one year was only 38%.     

Acute Kidney Injury Enhances Outcome Prediction Ability of Sequential Organ Failure Assessment Score in Critically Ill Patients

Introduction

Acute kidney injury (AKI) is a common and serious complication in intensive care unit (ICU) patients and also often part of a multiple organ failure syndrome. The sequential organ failure assessment (SOFA) score is an excellent tool for assessing the extent of organ dysfunction in critically ill patients. This study aimed to evaluate the outcome prediction ability of SOFA and Acute Physiology and Chronic Health Evaluation (APACHE) III score in ICU patients with AKI.

Methods

A total of 543 critically ill patients were admitted to the medical ICU of a tertiary-care hospital from July 2007 to June 2008. Demographic, clinical and laboratory variables were prospectively recorded for post hoc analysis as predictors of survival on the first day of ICU admission.

Results

One hundred and eighty-seven (34.4%) patients presented with AKI on the first day of ICU admission based on the risk of renal failure, injury to kidney, failure of kidney function, loss of kidney function, and end-stage renal failure (RIFLE) classification. Major causes of the ICU admissions involved respiratory failure (58%). Overall in-ICU mortality was 37.9% and the hospital mortality was 44.7%. The predictive accuracy for ICU mortality of SOFA (areas under the receiver operating characteristic curves: 0.815±0.032) was as good as APACHE III in the AKI group. However, cumulative survival rates at 6-month follow-up following hospital discharge differed significantly (p<0.001) for SOFA score ≤10 vs. ≥11 in these ICU patients with AKI.

Conclusions

For patients coexisting with AKI admitted to ICU, this work recommends application of SOFA by physicians to assess ICU mortality because of its practicality and low cost. A SOFA score of ≥ “11” on ICU day 1 should be considered an indicator of negative short-term outcome.     

Prevalence of advanced renal failure in Northern Ireland.

OBJECTIVE--To determine the prevalence of advanced chronic renal failure in Northern Ireland as part of an assessment by the Renal Association of the level of service provision for treatment of such patients. DESIGN--Prospective notification of patients reaching a defined level of advanced chronic renal failure (serum creatinine concentration greater than or equal to 500 mumol/l or blood urea concentration greater than or equal to 25 mmol/l) within one year and follow up for at least three, and, at most, four years after notification. SETTING--Northern Ireland. PATIENTS--122 Patients with a serum creatinine or blood urea concentration higher than the defined level newly detected from 1 March 1985 to 28 February 1986. MAIN OUTCOME MEASURE--Survival after notification. RESULTS--77 Patients of all ages/million population/year had advanced chronic renal failure compared with 67/million/year between the ages of 5 and 80 found in an earlier study of the same population. 62% Of the patients were older than 50 years. Seventeen (14%) of the patients either required dialysis or died within one month of notification, 51 (42%) survived for at least three months, and 23 (19%) for one year or longer. Three patients, all of whom were attending a renal clinic, survived for periods of 43, 45, and 46 months respectively without renal replacement treatment. CONCLUSIONS--The increased number of new patients disclosed in this survey compared with the earlier survey is mainly owing to an increased number of older patients. Such patients often have disabilities other than renal failure, are less likely to be capable of self treatment, may develop complications more often and require more frequent hospital admissions, and may not be suitable for transplantation and consequently have considerable resource implications for the NHS.     

GERIATRIC PATIENTS IN A MENTAL HOSPITAL

An intensive study was made of men 55 years of age and over admitted to Napa State Hospital with either senile or arteriosclerotic brain disease. A ward treatment program, combining both the medical and psychiatric approaches, was applied to one-half of such patients admitted to a state hospital, with the aim of determining what, if any, effect this program would have on the course of the illnesses.Special laboratory studies showed: (a) Serial electroencephalograms and hospital adjustment ratings appeared to be positively correlated with the patients'' clinical course; (b) In 35 per cent of cases the electrocardiographic tracings at the time of admittance were within normal limits; (c) A “pathological level” of blood bromides was found in only one of 340 consecutive admissions in this age group.Sociopsychiatric study of 100 consecutively admitted patients revealed that: (a) 35 per cent of the patients were from the middle, and 65 per cent from the lower classes of society; (b) Only 59 per cent were admitted because of activities specifically psychotic. (c) 63 per cent needed admittance to this state hospital for observation and diagnosis, but only 44 per cent needed to stay for care and treatment; (d) In 88 per cent, specific emotional stresses were present just preceding and coincident with the clinical appearance of the organic brain syndrome.     

Multimorbidity combinations,costs of hospital care and potentially preventable emergency admissions in England: A cohort study

BackgroundPatients with multimorbidities have the greatest healthcare needs and generate the highest expenditure in the health system. There is an increasing focus on identifying specific disease combinations for addressing poor outcomes. Existing research has identified a small number of prevalent “clusters” in the general population, but the limited number examined might oversimplify the problem and these may not be the ones associated with important outcomes. Combinations with the highest (potentially preventable) secondary care costs may reveal priority targets for intervention or prevention. We aimed to examine the potential of defining multimorbidity clusters for impacting secondary care costs.Methods and findingsWe used national, Hospital Episode Statistics, data from all hospital admissions in England from 2017/2018 (cohort of over 8 million patients) and defined multimorbidity based on ICD-10 codes for 28 chronic conditions (we backfilled conditions from 2009/2010 to address potential undercoding). We identified the combinations of multimorbidity which contributed to the highest total current and previous 5-year costs of secondary care and costs of potentially preventable emergency hospital admissions in aggregate and per patient. We examined the distribution of costs across unique disease combinations to test the potential of the cluster approach for targeting interventions at high costs. We then estimated the overlap between the unique combinations to test potential of the cluster approach for targeting prevention of accumulated disease. We examined variability in the ranks and distributions across age (over/under 65) and deprivation (area level, deciles) subgroups and sensitivity to considering a smaller number of diseases.There were 8,440,133 unique patients in our sample, over 4 million (53.1%) were female, and over 3 million (37.7%) were aged over 65 years. No clear “high cost” combinations of multimorbidity emerged as possible targets for intervention. Over 2 million (31.6%) patients had 63,124 unique combinations of multimorbidity, each contributing a small fraction (maximum 3.2%) to current-year or 5-year secondary care costs. Highest total cost combinations tended to have fewer conditions (dyads/triads, most including hypertension) affecting a relatively large population. This contrasted with the combinations that generated the highest cost for individual patients, which were complex sets of many (6+) conditions affecting fewer persons. However, all combinations containing chronic kidney disease and hypertension, or diabetes and hypertension, made up a significant proportion of total secondary care costs, and all combinations containing chronic heart failure, chronic kidney disease, and hypertension had the highest proportion of preventable emergency admission costs, which might offer priority targets for prevention of disease accumulation. The results varied little between age and deprivation subgroups and sensitivity analyses.Key limitations include availability of data only from hospitals and reliance on hospital coding of health conditions.ConclusionsOur findings indicate that there are no clear multimorbidity combinations for a cluster-targeted intervention approach to reduce secondary care costs. The role of risk-stratification and focus on individual high-cost patients with interventions is particularly questionable for this aim. However, if aetiology is favourable for preventing further disease, the cluster approach might be useful for targeting disease prevention efforts with potential for cost-savings in secondary care.

Jonathan Stokes and co-workers explore patterns of multimorbidity and implications for the organization and costs of care.     

Predicting cardiovascular risk in England and Wales: prospective derivation and validation of QRISK2

Objective To develop and validate version two of the QRISK cardiovascular disease risk algorithm (QRISK2) to provide accurate estimates of cardiovascular risk in patients from different ethnic groups in England and Wales and to compare its performance with the modified version of Framingham score recommended by the National Institute for Health and Clinical Excellence (NICE).Design Prospective open cohort study with routinely collected data from general practice, 1 January 1993 to 31 March 2008.Setting 531 practices in England and Wales contributing to the national QRESEARCH database.Participants 2.3 million patients aged 35-74 (over 16 million person years) with 140 000 cardiovascular events. Overall population (derivation and validation cohorts) comprised 2.22 million people who were white or whose ethnic group was not recorded, 22 013 south Asian, 11 595 black African, 10 402 black Caribbean, and 19 792 from Chinese or other Asian or other ethnic groups.Main outcome measures First (incident) diagnosis of cardiovascular disease (coronary heart disease, stroke, and transient ischaemic attack) recorded in general practice records or linked Office for National Statistics death certificates. Risk factors included self assigned ethnicity, age, sex, smoking status, systolic blood pressure, ratio of total serum cholesterol:high density lipoprotein cholesterol, body mass index, family history of coronary heart disease in first degree relative under 60 years, Townsend deprivation score, treated hypertension, type 2 diabetes, renal disease, atrial fibrillation, and rheumatoid arthritis.Results The validation statistics indicated that QRISK2 had improved discrimination and calibration compared with the modified Framingham score. The QRISK2 algorithm explained 43% of the variation in women and 38% in men compared with 39% and 35%, respectively, by the modified Framingham score. Of the 112 156 patients classified as high risk (that is, ≥20% risk over 10 years) by the modified Framingham score, 46 094 (41.1%) would be reclassified at low risk with QRISK2. The 10 year observed risk among these reclassified patients was 16.6% (95% confidence interval 16.1% to 17.0%)—that is, below the 20% treatment threshold. Of the 78 024 patients classified at high risk on QRISK2, 11 962 (15.3%) would be reclassified at low risk by the modified Framingham score. The 10 year observed risk among these patients was 23.3% (22.2% to 24.4%)—that is, above the 20% threshold. In the validation cohort, the annual incidence rate of cardiovascular events among those with a QRISK2 score of ≥20% was 30.6 per 1000 person years (29.8 to 31.5) for women and 32.5 per 1000 person years (31.9 to 33.1) for men. The corresponding figures for the modified Framingham equation were 25.7 per 1000 person years (25.0 to 26.3) for women and 26.4 (26.0 to 26.8) for men). At the 20% threshold, the population identified by QRISK2 was at higher risk of a CV event than the population identified by the Framingham score.Conclusions Incorporating ethnicity, deprivation, and other clinical conditions into the QRISK2 algorithm for risk of cardiovascular disease improves the accuracy of identification of those at high risk in a nationally representative population. At the 20% threshold, QRISK2 is likely to be a more efficient and equitable tool for treatment decisions for the primary prevention of cardiovascular disease. As the validation was performed in a similar population to the population from which the algorithm was derived, it potentially has a “home advantage.” Further validation in other populations is therefore advised.     

Severity Assessment of Lower Respiratory Tract Infection in Malawi: Derivation of a Novel Index (SWAT-Bp) Which Outperforms CRB-65

Objective

To assess the validity of CRB-65 (Confusion, Respiratory rate >30 breaths/min, BP<90/60 mmHg, age >65 years) as a pneumonia severity index in a Malawian hospital population, and determine whether an alternative score has greater accuracy in this setting.

Design

Forty three variables were prospectively recorded during the first 48 hours of admission in all patients admitted to Queen Elizabeth Central Hospital, Malawi, for management of lower respiratory tract infection over a two month period (N = 240). Calculation of sensitivity and specificity for CRB-65 in predicting mortality was followed by multivariate modeling to create a score with superior performance in this population.

Results

Median age 37, HIV prevalence 79.9%, overall mortality 18.3%. CRB-65 predicted mortality poorly, indicated by the area under the ROC curve of 0.649. Independent predictors of death were: Male sex, “S” (AOR 2.6); Wasting, “W” (AOR 6.6); non-ambulatory, “A” (AOR 2.5); Temp >38°C or <35°C, “T” (AOR 3.2); BP<100/60, “Bp” (AOR 3.7). Combining these factors to form a severity index (SWAT-Bp) predicted mortality with high sensitivity and specificity (AUC: 0.867). Mortality for scores 0–5 was 0%, 3.3%, 7.4%, 29.2%, 61.5% and 87.5% respectively. A score ≥3 was 84% sensitive and 77% specific for mortality prediction, with a negative predictive value of 95.8%.

Conclusion

CRB-65 performs poorly in this population. The SWAT-Bp score can accurately stratify patients; ≤2 indicates non-severe infection (mortality 4.4%) and ≥3 severe illness (mortality 45%).     

Comprehensive Characterization of Human Genome Variation by High Coverage Whole-Genome Sequencing of Forty Four Caucasians

Whole genome sequencing studies are essential to obtain a comprehensive understanding of the vast pattern of human genomic variations. Here we report the results of a high-coverage whole genome sequencing study for 44 unrelated healthy Caucasian adults, each sequenced to over 50-fold coverage (averaging 65.8×). We identified approximately 11 million single nucleotide polymorphisms (SNPs), 2.8 million short insertions and deletions, and over 500,000 block substitutions. We showed that, although previous studies, including the 1000 Genomes Project Phase 1 study, have catalogued the vast majority of common SNPs, many of the low-frequency and rare variants remain undiscovered. For instance, approximately 1.4 million SNPs and 1.3 million short indels that we found were novel to both the dbSNP and the 1000 Genomes Project Phase 1 data sets, and the majority of which (∼96%) have a minor allele frequency less than 5%. On average, each individual genome carried ∼3.3 million SNPs and ∼492,000 indels/block substitutions, including approximately 179 variants that were predicted to cause loss of function of the gene products. Moreover, each individual genome carried an average of 44 such loss-of-function variants in a homozygous state, which would completely “knock out” the corresponding genes. Across all the 44 genomes, a total of 182 genes were “knocked-out” in at least one individual genome, among which 46 genes were “knocked out” in over 30% of our samples, suggesting that a number of genes are commonly “knocked-out” in general populations. Gene ontology analysis suggested that these commonly “knocked-out” genes are enriched in biological process related to antigen processing and immune response. Our results contribute towards a comprehensive characterization of human genomic variation, especially for less-common and rare variants, and provide an invaluable resource for future genetic studies of human variation and diseases.     

Plasma creatinine and urea: creatinine ratio in patients with raised plasma urea.

We examined the plasma urea and creatinine concentrations and the ratio between them according to diagnosis in 100 unselected and 31 selected adult hospital patients with a plasma urea concentration greater than or equal to 10 mmol/l (60mg/100ml). We also examined plasma urea and creatinine concentrations in 350 unselected consecutive patients, but found no useful relation between the two values. Congestive heart failure was the most common identifiable cause of a raised plasma urea concentration in the 100 unselected patients (36%). Among these 100 patinets the plasma creatinine concentration was a more useful discriminant between prerenal uraemia and intrinsic renal failure than was the urea:creatinine ratio or the plasma urea concentration. A plasma creatinine concentration greater than 250 mumol/1 (2-8 mg/100ml) indicated intrinsic renal failure with a 90% probability.     

Fibrinogen Catabolism Study of Three Patients with Bacterial Endocarditis and Renal Disease

Three patients with bacterial endocarditis who developed renal failure have been studied by means of a radiofibrinogen catabolism study. Two were studied at the time of bacteraemia and one during the subsequent “immunological phase” of circulating immune complexes. Accelerated fibrinogen catabolism was found in all cases. Intravascular coagulation may be an important factor in the pathogenesis of proliferative glomerulonephritis in such cases.