Active treatment in low-risk prostate cancer: a population-based study

Background

Active surveillance instead of active treatment (at) is preferred for patients with low-risk prostate cancer (lr-pca), but practice varies widely. We conducted a population-based study to assess the proportion of patients who underwent at between January 2011 and December 2014, and to evaluate factors associated with at.

Methods

The provincial cancer registry was linked to administrative health datasets to identify patients with lr-pca and to acquire demographic, tumour, and treatment data. The primary outcome was receipt of at during the first 12 months after diagnosis, defined as any receipt of external-beam radiotherapy, brachytherapy, radical prostatectomy, cryotherapy, or androgen deprivation. Univariate and multivariate logistic regression were used to analyze the correlation between patient and tumour factors and at.

Results

Of 1565 patients with lr-pca, 554 (35.4%) underwent at within 12 months of diagnosis. Radical prostatectomy was the most common treatment (58%), followed by brachytherapy (29.6%). Younger age [odds ratio (or) 0.92; 95% confidence interval (ci): 0.91 to 0.94], lower score (≥3) on the Charlson comorbidity index (OR: 0.36; 95% ci: 0.19 to 0.68), T2 stage (or: 3.05; 95% ci: 2.03 to 4.58), higher prostate-specific antigen (psa) at diagnosis (or: 1.13; 95% ci: 1.06 to 1.21), radiation oncologist consultation (or: 3.35; 95% ci: 2.55 to 4.39), and earlier diagnosis year (2012 or: 0.46; 95% ci: 0.34 to 0.63; 2013 or: 0.45; 95% ci: 0.32 to 0.63; 2014 or: 0.33; 95% ci: 0.23 to 0.47) were associated with a higher probability of at.

Conclusions

This contemporary population-based study demonstrates that approximately one third of patients with lr-pca undergo at. Patients of younger age, with less comorbidity, a higher tumour stage, higher psa, earlier year of diagnosis, and radiation oncologist consultation were more likely to undergo at. Further investigation is needed to identify strategies that could minimize overtreatment.

Roentgenologic Assessment of Spondylolisthesis

Variations when measuring slip and lumbar index were studied in three lumbar specimens with different degrees of artificially created L5-S1 spondylolisthesis. Lateral radiographs were obtained with the specimens tilted and/or rotated mimicking an every-day examination situation. Slip and lumbar index were measured; slip was estimated according to a measuring method advocated by Boxall et coll. (3) but slightly modified by us. Six radiologists evaluated each film independently. The magnitude of interobserver and intraobserver errors and variations due to positioning was found to be equally large—about 15 per cent each. Although the total measurement variation was not equal to the sum of errors involved, radiologic evaluation of degree of spondylolisthesis was found to be highly unreliable.

Roentgenologic Assessment of Spondylolisthesis

Different degrees of artificial L5-SI spondylolisthesis were created using a lumbar specimen. Lateral radiographs were obtained of each, with the specimen tilted and/or rotated. The true spondylolisthesis was determined stereophotogrammetrically. The slip, measured on the radiographs, was calculated according to two methods modified from Boxall et coll. (2). No significant difference in accuracy was found between these two methods. The difference in calculated slip between examinations needs to be at least 20 per cent of the sagittal length of L5 to be regarded as a true progression. A true progress of slip of less than 20 per cent is difficult to detect with statistical certainty.

Analysis of intraprostatic therapeutic effects in prostate cancer patients using [(11)C]-choline pet/ct after external-beam radiation therapy

PURPOSE

The objective of the present study was to analyze, with relatively high sensitivity and specificity, uptake properties of [(11)C]-choline in prostate cancer patients by means of positron-emission tomography (pet)/computed tomography (ct) imaging using objectively defined pet parameters to test for statistically significant changes before, during, and after external-beam radiation therapy (ebrt) and to identify the time points at which the changes occur.

METHODS

The study enrolled 11 patients with intermediate-risk prostate cancer treated with ebrt, who were followed for up to 12 months after ebrt. The [(11)C]-choline pet scans were performed before treatment (baseline); at weeks 4 and 8 of ebrt; and at 1, 2, 3, 6, and 12 months after ebrt.

RESULTS

Analysis of [(11)C]-choline uptake in prostate tissue before treatment resulted in a maximum standardized uptake value (suvmax) of 4.0 ± 0.4 (n = 11) at 40 minutes after injection. During week 8 of ebrt, the suvmax declined to 2.9 ± 0.1 (n = 10, p < 0.05). At 2 and 12 months after ebrt, suvmax values were 2.3 ± 0.3 (n = 10, p < 0.01) and 2.2 ± 0.2 (n = 11, p < 0.001) respectively, indicating that, after ebrt, maximum radiotracer uptake in the prostate was significantly reduced. Similar effects were observed when analyzing the tumour:muscle ratio (tmr). The tmr declined from 7.4 ± 0.6 (n = 11) before ebrt to 6.1 ± 0.4 (n = 11, nonsignificant) during week 8 of ebrt, to 5.6 ± 0.03 (n = 11, p < 0.05) at 2 months after ebrt, and to 4.4 ± 0.4 (n = 11, p < 0.001) at 12 months after ebrt.

CONCLUSIONS

Our study demonstrated that intraprostatic [(11)C]-choline uptake in the 11 analyzed prostate cancer patients significantly declined during and after ebrt. The pet parameters SUVmax and tmr also declined significantly. These effects can be detected during radiation therapy and up to 1 year after therapy. The prognostic value of these early and statistically significant changes in intraprostatic [(11)C]-choline pet avidity during and after ebrt are not yet established. Future studies are indicated to correlate changes in [(11)C]-choline uptake parameters with long-term biochemical recurrence to further evaluate [(11)C]-choline pet changes as a possible, but currently unproven, biomarker of response.

Hypertension after kidney transplantation

BACKGROUND

Few studies have examined the possible role of blood pressure (BP), independent of acute rejection and graft function, on outcomes after kidney transplantation.

METHODS

We investigated the prevalence, treatment, control, and clinical correlates of hypertension and its association with outcomes, using multivariate analyses with time-dependent covariates, in a retrospective cohort of 1,666 kidney transplant recipients.

RESULTS

Hypertension was common, and its control was poor. For example, at 1 year, only 55.5% had a BP less than 140 mm Hg. Control improved only slightly in 1993-2002 compared to 1976-2002, even as patients administered 2 or more antihypertensive medications at 1 year increased from 43.5% to 54.6%. Independent correlates of higher BP included male sex, age, donor age, diabetes, body mass index, the presence of native kidneys, and delayed graft function. Previous acute rejection was associated with higher BP at virtually all times after transplantation, and these associations were independent of estimated creatinine clearance (C(Cr)). Conversely, an association between BP and subsequent acute rejection was not statistically significant when differences in C(Cr) were taken into account. After adjusting for the effects of acute rejection, C(Cr), and other variables, each 10 mm Hg of systolic BP was associated with an increased relative risk for graft failure (1.12; 95% confidence interval, 1.08 to 1.15; P < 0.0001), death-censored graft failure (1.17; 1.12 to 1.22; P < 0.0001), and death (1.18; 1.12 to 1.23; P < 0.0001).

CONCLUSION

High BP is closely tied to graft function, but nevertheless is an independent risk factor for graft failure and mortality. Better strategies are needed to control BP after kidney transplantation.

A thirty percent chronic decline in inverse serum creatinine is an excellent predictor of late renal allograft failure

We previously reported that the percentage of change in inverse serum creatinine (Delta1/Cr) was the best of several time-dependent serum creatinine-derived predictors of renal allograft failure in patients not administered cyclosporine (CsA). To further validate the utility of Delta1/Cr, we collected creatinine levels (mean, 90.7 +/- 45.2 creatinine measurements) in 100 patients treated for 6.7 +/- 5.9 years with CsA. We also validated Delta1/Cr using a limited creatinine-sampling strategy, then performed multivariate Cox proportional hazards analysis of 1,663 transplantations. A time-dependent covariate determined by the date of first chronic decline (excluding creatinine levels from periods of acute rejection) in Delta1/Cr to less than -30% of baseline similarly was predictive of graft failure in 101 patients treated without CsA (relative risk, 5.04; 95% confidence interval, 2.18 to 11.6; P = 0.0002) and 100 patients treated with CsA (relative risk, 5.02; 95% confidence interval, 2.50 to 10.1; P < 0.0001). A limited creatinine-sampling strategy (measured at 1 week, 1, 3, 6, 12, 18, 24, and 36 months, and each year thereafter) reduced the ability of Delta1/Cr less than -30% to predict graft failure. In 1,663 patients, Delta1/Cr less than -30% first occurred a median of 1.0 years posttransplantation (n = 792 of 1,663 patients) and 3.0 years before graft failure (n = 478 of 897 patients with graft failure). In a multivariate model (n = 1,663) that included baseline function, acute rejection, and other covariates, Delta1/Cr less than -30% was a strong independent predictor of graft failure (relative risk, 2.56; 95% confidence interval, 2.12 to 3.09; P < 0.0001). Thus, Delta1/Cr less than -30% is an excellent predictor of graft failure that is similarly predictive in patients treated with and without CsA. A limited sampling strategy for creatinine diminishes, but does not negate, the usefulness of Delta1/Cr less than -30%.

Defining the risk of elective cyclosporine withdrawal in stable kidney transplant recipients

Although it is known that elective cyclosporine (CsA) withdrawal increases the risk for acute rejection, few studies have been large enough to identify risk factors for acute rejection after CsA withdrawal. We examined risk factors for acute rejection in 464 kidney transplant recipients who underwent elective CsA withdrawal. The incidence of acute rejection within 6 months of CsA withdrawal was 20/141 (14.2%) in the period January 1986 to May 1989, but only 14/323 (4.5%) since May 1989 (p = 0.0002). Among those transplanted since May 1989, the incidence was 5/20 (25%) for those with both 2 HLA-B and 2 HLA-DR mismatches, compared with only 9/298 (3.0%) for those with fewer mismatches (p < 0.0001). In Cox proportional hazards analysis, risk factors for acute rejection within 6 months, or at any time after elective CsA withdrawal, were date of transplant January 1986 to May 1989 (compared with more recently May 1989 to March 1999), younger age, obesity, as well as B and DR mismatches. Recipient race (83% were white), acute rejection during the first year before withdrawal (31%), mycophenolate mofetil (17%), and other variables failed to predict postwithdrawal acute rejection. We concluded that avoiding CsA withdrawal in the relatively small number of recipients with both 2 HLA-B and 2 HLA-DR mismatches could further reduce our already low incidence of acute rejection following elective CsA withdrawal.

Axially loaded magnetic resonance image of the lumbar spine in asymptomatic individuals

STUDY DESIGN

For this study, 43 asymptomatic individuals underwent magnetic resonance imaging of the lumbar spine in both supine psoas-relaxed position and supine axial compression in extension. The change in dural cross-sectional area between positions at each disc level was calculated.

OBJECTIVES

To evaluate the effect of axial loading on asymptomatic individuals, as compared with the effect on patients who have clinical signs of lumbar spinal canal stenosis, and to assess the effect that different magnitude and duration of the applied load have on the dural cross-sectional area.

SUMMARY OF BACKGROUND DATA

Degenerative changes in the spine are found in both symptomatic and asymptomatic individuals. A study of patients with suspected clinical lumbar spine encroachment examined in both psoas-relaxed position and axial compression in extension with computed tomographic myelography or magnetic resonance imaging of the lumbar spine is reported. A significant decrease in dural cross-sectional area was found, respectively, in 80% and 76% of the patients.

METHODS

The study subjects underwent magnetic resonance imaging examinations in both psoas-relaxed position and axial compression in extension. The examination of the subject under axial compression in extension was performed with the lumbar spine in a supine position using a compression device. Degenerative changes in and adjacent to the spinal canal were registered. The dural cross-sectional areas were determined for psoas-relaxed position and axial compression in extension, then compared. In seven reexamined individuals, the dural cross-sectional area was calculated after an axial load corresponding to 25% and 50% of their body weight and a loading time of 5 to 60 minutes.

RESULTS

A significant decrease in dural cross-sectional area from psoas-relaxed position to axial compression in extension was found in 24 individuals (56%), most frequently at L4-L5, and increasingly with age. In four individuals (5 disc levels), a decrease in dural cross-sectional area to less than 100 mm2 from psoas-relaxed position to axial compression in extension was found. In seven reexamined individuals, a significant decrease in dural cross-sectional area was found: in five after 5 minutes load of 25% of their body weight, and in two with 50% of their body weight.

CONCLUSIONS

Using magnetic resonance imaging, a significant decrease in dural cross-sectional area after axial loading was found less frequently in asymptomatic than in symptomatic subjects. The decrease was more frequent at L4-L5, and increasingly with age. The load should be 50% of the subject's body weight applied for at least 5 minutes.

The diagnostic effect from axial loading of the lumbar spine during computed tomography and magnetic resonance imaging in patients with degenerative disorders

STUDY DESIGN

Patients with low back pain, sciatica, and neurogenic claudication were observed during computed tomographic myelography or magnetic resonance imaging in psoas-relaxed position and axially compressed supine position of the lumbar spine.

OBJECTIVE

To estimate the clinical value of axially loaded imaging in patients with degenerative disorders of the lumbar spine.

SUMMARY OF BACKGROUND DATA

Computed tomography and magnetic resonance imaging still are performed with the lumbar spine in a supine relaxed position, which results in unloading of the spine and enlargement of the canal.

METHODS

A device for axial loading of the lumbar spine in computed tomography and magnetic resonance imaging was used. Altogether, 172 patients were examined in psoas-relaxed position and axially compressed supine position of the lumbar spine: 50 patients with computed tomographic myelography and 122 patients with magnetic resonance imaging. If a significant decrease (>15 mm2) in the dural sac cross-sectional area to values smaller than 75 mm2 (the borderline value for stenosis) was found during examination in axial loading, or if a suspected disc herniation, narrow lateral recess, narrow intervertebral foramen, or intraspinal synovial cyst changed to being obvious at the axial loading examination, this was regarded as additional information important for the treatment.

RESULTS

Additional valuable information was found in 50 of 172 patients (29%) during examination in axial loading. In the different diagnostic groups, additional valuable information was found in 69% of the patients with neurogenic claudication, in 14% of the patients with sciatica, and in 0% of the patients with low back pain. The percentage of additional valuable information increased to 50% in the patients with sciatica, if recommended inclusion criteria for examinations in axial loading were used. A narrowing of the lateral recess causing compression of the nerve root was found at 42 levels in 35 patients at axial loading.

CONCLUSION

According to the study results, axially loaded imaging adds frequent additional valuable information, as compared with conventional imaging methods, especially in patients with neurogenic claudication, but also in patients with sciatica if defined inclusion criteria are used.

Comparing methods for monitoring serum creatinine to predict late renal allograft failure

Few studies have systematically investigated what changes in chronic renal allograft function best predict subsequent graft failure, when these changes occur, and whether they occur soon enough to allow possible intervention. We collected serum creatinine values (mean, 183 +/- 75 values/patient) measured over a maximum follow-up of 22 years in 101 consecutive renal transplant recipients (excluding creatinine levels from periods of acute rejection). We determined the dates of first decline in inverse creatinine (Delta1/Cr; < -20%, -30%, -40%, -50%, and -70%), declines in estimated creatinine clearance (CCr; <55, 45, 35, 25, and 15 mL/min), and declines in measured slope of 1/Cr over time. We used time-dependent covariates in Cox proportional hazards analyses to determine the relative effect of each renal function parameter on outcomes while adjusting for other risk factors. The best predictor of subsequent graft failure was Delta1/Cr. Delta1/Cr less than -40% first occurred at a median of 1.28 years after transplantation in 73 patients, and 67 patients went on to have graft failure a median of 3.28 years after Delta1/Cr less than -40%. The independent relative risk for graft failure attributable to Delta1/Cr less than -40% was 5.91 (95% confidence interval, 3.25 to 10.8; P < 0.0001). A decline in CCr, eg, less than 45 mL/min, also was a strong predictor of subsequent graft failure. Conversely, declines in allograft function estimated from slopes of 1/Cr were poor predictors of graft failure. In analysis limited to patients followed up for 2.5 years or less, Delta1/Cr continued to predict graft failure, suggesting that Delta1/Cr will be a useful predictor in populations with shorter follow-up. If confirmed in other populations, eg, patients treated with calcineurin inhibitors, this simple marker of chronic allograft dysfunction may prove to be a practical tool for defining patients at high risk for late graft failure.

Cytomegalovirus disease is not a major risk factor for ischemic heart disease after renal transplantation

BACKGROUND

It has been suggested that cytomegalovirus infection increases the risk of ischemic heart disease. Both cytomegalovirus and ischemic heart disease are common after renal transplantation, suggesting a possible causal association in this population.

METHODS AND PATIENTS

We studied 1004 consecutive renal transplants with no prior history of ischemic heart disease and grafts that functioned at least 12 months. We performed univariate and multivariate analyses to examine the effect of cytomegalovirus disease and other risk factors (measured during the first posttransplant year) on the development of primary ischemic heart disease events after the first posttransplant year.

RESULTS

More than 1 year after transplantation, 116 patients (11.6%) experienced their first ischemic event (75 myocardial infarction, 12 percutaneous angioplasty, 18 bypass grafting, and 11 deaths). Patients with ischemic heart disease were more likely to have known risk factors (age, diabetes, smoking, hypercholesterolemia, systolic blood pressure, low serum albumin, and acute rejections). However, the incidence of cytomegalovirus disease was not different for those with or without ischemic heart disease (36.2% vs. 31.1%). Moreover, a similar proportion of those with and without ischemic heart disease (19.8% vs. 15.5%) had a rise in cytomegalovirus antibodies during follow-up. By multivariate analysis, risk factors for ischemic heart disease (P<0.05) were age, diabetes, smoking, low serum albumin, and two or more acute rejections during the first year. Cytomegalovirus disease was not associated with ischemic heart disease events: unadjusted relative risk=1.14 (95% confidence interval 0.78-1.67, P=0.485). After adjusting for multiple risk factors, the relative risk was 0.91 (0.60-1.37, P=0.657).

CONCLUSION

These data suggest that cytomegalovirus disease is not a significant risk factor for the development of primary ischemic heart disease after renal transplantation.

Fluid balance in patients with chronic renal failure assessed with N-terminal proatrial natriuretic peptide, atrial natriuretic peptide and ultrasonography

The N-terminal proatrial natriuretic peptide (proANP) has become an important parameter for assessing the prognosis of patients with cardiac disease. Its use for evaluating the hydration status in patients with chronic renal failure, however, is still under investigation. The present study comprised 12 haemodialysis (HD) and 17 pre-dialysis patients. In the HD patients, the inferior vena cava diameter during quiet expiration (IVCe) was estimated by ultrasonography and plasma concentrations of N-terminal proANP, atrial natriuretic peptide (ANP) and cyclic guanosine monophosphate (cGMP) were measured before and 4 h after termination of HD. In the pre-dialysis patients venous blood samples were taken during rest to measure plasma N-terminal proANP and ANP and serum creatinine. Normal values for N-terminal proANP and ANP were obtained from 18 healthy volunteers. The plasma concentrations of N-terminal proANP and ANP in healthy volunteers were 328 +/- 92 and 11.4.0 +/- 3.1 pM L-1, respectively. In pre-dialysis patients, serum creatinine ranged from 110 to 447 microM L-1 and was significantly correlated to plasma N-terminal proANP (r = 0.60, P < 0.05) but not to ANP. This may indicate that N-terminal proANP is more dependent on renal function for its clearance than ANP, which is probably cleared by extrarenal mechanisms as well. In HD patients, IVCe was significantly correlated to the three hormones before HD, most strongly to N-terminal proANP. After dialysis, IVCe was significantly correlated to ANP and cGMP but was not correlated to N-terminal proANP. This may suggest that proANP takes a longer time than other hormones to reflect changes in intravascular volume. In conclusion, N-terminal proANP is a hormone closely related to degree of renal function. Furthermore, it is a sensitive marker reflecting the interdialytic hydration status in HD patients, as indicated by its high correlation to IVCe, a standard method which is used frequently nowadays to assess the body hydration. However N-terminal proANP could not reflect the acute changes in fluid volume induced by HD, probably because it is slowly metabolized.

TTX blocks baclofen-induced phase shifts of the mammalian circadian pacemaker in vitro

The mammalian circadian pacemaker, located in the suprachiasmatic nucleus (SCN), expresses 24-h rhythms when isolated in vitro. The GABA(A) agonist, muscimol, induces phase advances during the mid-subjective day, while the GABA(B) agonist, baclofen, induces both daytime phase advances and nighttime phase delays. Here, we present evidence that tetrodotoxin (TTX) completely blocks baclofen-induced phase shifts in vitro, but does not block in vitro phase advances induced by muscimol. These results suggest that GABA(A), but not GABA(B), receptors are located on SCN pacemaker cells.

Long-term results and complications of renal transplantation: the Hennepin experience

Approximately one sixth of patients receiving renal transplants have a functioning kidney beyond 20 years. Chronic rejection is the predominant cause of late allograft loss. Malignancy, cardiovascular disease, hepatic failure, and infections are the major causes of late death. Early detection and control of the risk factors that contribute to patient death should favorably influence the long-term success of renal transplantation.

"True" mycotic aneurysm of a renal artery allograft

A 60-year-old white man sustained a rupture of the renal artery 6 weeks after a cadaveric kidney transplantation. The bleeding site was repaired, and culture of the hematoma showed an isolated growth of Candida albicans. Blood and urine cultures were negative. Systemic antifungal therapy was initiated. Bleeding from the renal artery recurred, eventually requiring removal of the transplanted kidney. Histopathology of the resected specimen showed budding yeast in the wall of the renal artery, but no evidence of fungal invasion of the kidney. The patient received 6 weeks of amphotericin B therapy and currently remains on hemodialysis therapy.

Dynamic effects on the lumbar spinal canal: axially loaded CT-myelography and MRI in patients with sciatica and/or neurogenic claudication

STUDY DESIGN

In patients with sciatica or neurogenic claudication, the structures in and adjacent to the lumbar spinal canal were observed by computed tomographic myelography or magnetic resonance imaging in psoas-relaxed position and during axial compression in slight extension of the lumbar spine.

OBJECTIVES

To determine the mechanical effects on the lumbar spinal canal in a simulated upright position.

SUMMARY OF BACKGROUND DATA

For years, functional myelographic investigation techniques were shown to be of value in the evaluation of suspected encroachment of the spinal canal. Since the advent of computed tomography and magnetic resonance imaging, there have been few clinical and experimental attempts that have imitated these techniques. The data indicate that the space within the canal is posture dependent.

METHODS

Portable devices for axial loading of the lumbar spine in computed tomographic and magnetic resonance examinations were developed. Fifty patients (94 sites) were studied with computed tomographic myelography, and 34 patients (80 sites) with magnetic resonance in psoas-relaxed position followed by axial compression in slight extension. The dural sac cross-sectional area at L2 to S1, the deformation of the dural sac and the nerve roots, and the changes of the tissues surrounding the canal were observed.

RESULTS

In 66 of the investigated 84 patients, there was a statistically significant reduction of the dural sac cross-sectional area in at least one site during axial compression in slight extension. Of the investigated patients, 29 passed the borderlines for relative (100 mm2) or absolute stenosis (75 mm2) in 40 sites. In 30 patients, there was deformation of the dural sac in 46 sites. In 11 of the patients investigated with magnetic resonance imaging, there was a narrowing of the lateral recess in 13 sites, during axial compression in slight extension.

CONCLUSIONS

Axial loading of the lumbar spine in computed tomographic scanning and magnetic resonance imaging is recommended in patients with sciatica or neurogenic claudication when the dural sac cross-sectional area at any disc location is below 130 mm2 in conventional psoas-relaxed position and when there is a suspected narrowing of the dural sac or the nerve roots, especially in the ventrolateral part of the spinal canal in psoas-relaxed position. The diagnostic specificity of the spinal stenosis will increase considerably when the patient is subjected to an axial load.

Isolation of haemorphin-related peptides from filter membranes collected in connection with haemofiltration of human subjects

This paper describes the extraction and isolation from dialysis filters of two peptides containing the opioid active sequence haemorphin-7. The filter devices were obtained from uraemic patients subjected to haemofiltration. Following acidic extraction of the filter membranes the peptides were purified by size-exclusion, ion-exchange chromatography and finally by reversed-phase chromatography using different columns and different chromatographic systems. The purification was guided by radioimmunoassay and the structure of the final products was elucidated by N-terminal sequencing and fast-atom bombardment mass spectrometry as well as micro-electrospray mass spectrometry. The isolated peptides were suggested to be identical to fragments 1-41 and 32-41 of the beta-chain of human haemoglobin.

R-HuEPO hyporesponsiveness--who and why?

The most common cause of limited response to recombinant human erythropoietin (r-HuEPO) is unrecognized, mild-to-moderate iron deficiency, either at the start of treatment or secondary to enhanced iron utilization by newly formed erythrocytes. Iron stores in patients with chronic renal failure (CRF) are often depleted through gastrointestinal bleeding, blood loss during haemodialysis, and blood sampling. Mobilization of iron stores may be inadequate, especially during rapid haemoglobin regeneration. Aluminium overload may also interfere with gastrointestinal and cellular iron uptake. Overt or unrecognized infection or inflammation is another common cause of hyporesponsiveness, and is a consequence of increased blood concentrations of cytokines such as tumour necrosis factor (TNF), interleukin-1 (IL-1), and interferon-gamma (IFN-gamma), which suppress erythrocyte stem-cell proliferation. Less common causes include severe secondary hyperparathyroidism and myeloma (during chemotherapy). Response to r-HuEPO can be best predicted by baseline fibrinogen (a marker of subclinical inflammation); baseline transferrin receptor (sTfR) concentrations (a marker of functional iron deficiency); and sTfR increment after 2 weeks (a marker of early change in erythropoietic activity).

Treatment of renal calcium stone disease with the synthetic glycosaminoglycan pentosan polysulphate

Glycosaminoglycans (GAGs) are potent inhibitors of calcium oxalate growth and aggregation. The synthetic GAG pentosan polysulphate (PPS) was used in the treatment of patients with renal calcium stone disease. Altogether, 121 patients were included in an open trial over a 3-year-period. The average stone episode rate and the stone operation rate were no different during treatment and in the pretreatment period. Altogether 48% of the patients were entirely stone-free during follow-up, whereas 29/56 patients who continued to form stones reported smaller stones that were more easily passed. It is concluded that there may be a role for PPS in the treatment of recurrent renal calcium stone disease, but a controlled study may be needed.

Roentgenologic assessment of spondylolisthesis. II. An evaluation of progression

Different degrees of artificial L5-S1 spondylolisthesis were created using a lumbar specimen. Lateral radiographs were obtained of each, with the specimen tilted and/or rotated. The true spondylolisthesis was determined stereophotogrammetrically. The slip, measured on the radiographs, was calculated according to two methods modified from Boxall et coll. No significant difference in accuracy was found between these two methods. The difference in calculated slip between examinations needs to be at least 20 per cent of the sagittal length of L5 to be regarded as a true progression. A true progress of slip of less than 20 per cent is difficult to detect with statistical certainty.

Inhibition of sodium urate crystal adherence to bladder surface by polysaccharide

Bladder surface glycosaminoglycan (polysaccharide) has been shown to act in a nonspecific manner as an antiadherence factor and may potentially be important in the pathogenesis (and prevention) of renal calculi. It has been shown that when present, bladder surface GAG will reduce the adherence of both calcium and calcium oxalate crystals. This study was conducted to see if a similar effect would be found with uric acid crystals, in that the presence of the normal bladder mucus with its contained GAG and exogenously supplied polysaccharide, pentosanpolysulfate, would be inhibitory to crystal adherence. Radioactively labeled uric acid crystals were made by dissolving 14C labeled sodium urate to a point of saturation at pH 7.5 and then rapidly lowering the pH to 5.5. These crystals were placed into four groups of bladders: 1) normal bladders, 2) bladders rendered mucus deficient with hydrochloric acid, 3) mucus deficient bladders which were pre-treated with sodium pentosanpolysulfate prior to crystal addition and 4) mucus deficient bladders to which were added crystals pretreated with pentosanpolysulfate. There was a significant rise in crystal adherence after acid treatment of the bladder, a 2.3-fold increase, which was blocked with prior treatment of the crystals with pentosanpolysulfate and to a lesser degree by pretreating mucus deficient bladders with pentosanpolysulfate.

Successful renal transplantation in progressive systemic sclerosis

Hemodialysis and renal transplantation were done in a patient with progressive systemic sclerosis and renal failure. The patient's clinical course following transplantation was uncomplicated, and a biopsy of the renal allograft done 14 months after transplantation did not show recurrence of the original disease. These observations favor the consideration of early renal transplantation in patients with scleroderma and renal failure.

Hepatic veno-occlusive disease in a renal transplant patient receiving azathioprine

Central vein phlebitis and occlusion developed in a patient who was receiving immunosuppressive therapy with azathioprine (Imuran) and prednisone after renal transplantation. He had been well for 1 year before evidence of liver disease was noted; once begun, it progressed to hepatocellular failure in spite of a change in immunosuppressants from azathioprine to cyclophosphamide. Several known causes of venoocclusive disease and the possible causes in this patient are discussed.

Acid-base status in dogs during long term anaesthesia

The acid-base status in dogs anaesthetized with chloralose or combinations of chloralose and barbiturates was studied. No surgical procedures were used to elucidate whether the anesthesia per se changes in the acid-base status. Irrespective of the anaesthetic used, a progressive metabolic acidosis developed after 2-3 hours. This progressed for several hours despite normal arterial blood pressure and pulse rate. A theoretical model, based on the results, is presented. Even the induction of anesthesia caused an impairment of the peripheral circulation. This impairment, in combination with rising body temperature, might be strong enough to cause a detectable metabolic acidosis. It is concluded that, as compared with blood pressure and pulse rate, the acid-base status of the blood is a reliable and early sign of the impairment of circulation during anesthesia.