Dual X-ray absorptiometry detects disease- and treatment-related alterations of bone density in prostate cancer patients

Metastatic bone disease is an important clinical problem which has proven difficult to study because of a lack of noninvasive investigative modalities. Here we show that dual-energy X-ray absorptiometry (DXA) scanning provides clinically useful information about the status of metastatic bone lesions in cancer patients undergoing palliative treatment. In the study group of 21 patients, a significant increase in metastatic bone mineral density (BMD) was confirmed in prostate (n = 14) relative to breast (n = 7) cancer patients. With respect to the prostate cancer cohort, further increases in lesional BMD were evident in all evaluable patients in whom biochemical progression occurred; conversely, lesional BMD declined in patients who had a partial response to therapy. BMD of uninvolved bone decreased with all types of androgen-deprivation therapy regardless of whether patients responded or relapsed. We conclude that BMD changes in both lesional and uninvolved bone are readily detectable in metastatic prostate cancer, and propose that DXA scanning represents a promising new approach to monitoring the natural history and therapeutic course of this disease.

Urinary catecholamine excretion in relation to renal function

The urinary excretions of the free catecholamines noradrenaline, adrenaline and dopamine were measured in 50 patients (33 men and 17 women) with chronic renal failure. Stability studies showed that the catecholamines were stable in unacidified urine as long as the pH was not greater than 7.5 and the urine was acidified within 2-3 h of collection. The outputs of noradrenaline and dopamine correlated positively with creatinine clearance and in patients with clearances above 40 mL/min were similar to those in healthy volunteers (n = 20). However, adrenaline output was not correlated with creatinine clearance although it was lower in patients with renal failure compared with healthy volunteers. The urinary free catecholamine output during the first 10 days after a renal transplant was significantly less than normal, presumably because renal function was still impaired. However, in patients treated with cyclosporin A (CyA) combined with prednisolone the catecholamine excretion was lower compared with those treated with CyA and azathioprine. Impairment in renal function can have a marked effect on the output of free catecholamines and must be borne in mind when interpreting values that may have pathological significance.

Bias due to incomplete follow up in a cohort study

AIM

To investigate the bias introduced by incomplete follow up in a cohort study of ocular outcome after premature birth.

METHODS

A geographically defined cohort of children born before 32 weeks' gestation was prospectively recruited at birth to study the ocular outcome at 2 years. On the basis of attendance at 2 years, the children's families were allocated to one of three groups: group 1 attended for follow up, group 2 were difficult to trace, and group 3 were very reluctant for assessment. All children were examined by a single ophthalmologist, masked to these groupings.

RESULTS

558 children (98.8% of study group) were examined, of whom 505 were in group 1, 20 in group 2, and 33 in group 3. The groups which were more difficult to study (groups 2 and 3) showed a significantly higher prevalence of ocular abnormalities, including strabismus (p=0. 02) and cicatricial retinopathy of prematurity (p=0.002) compared with those attending for follow up. Further, not all of these cases could have been identified by review of the children's previous records. Ocular abnormalities would be underestimated by 16% (11.3% in group 1 compared with 13.4% in the total cohort, p=0.77).

CONCLUSIONS

This study suggests that the prevalence of abnormalities would be underestimated by incomplete follow up, as those subjects who were most difficult to obtain for study had a significantly higher prevalence of abnormalities.

Risk factors for strabismus in children born before 32 weeks' gestation

AIM

To investigate risk factors associated with strabismus in children born prematurely.

METHODS

Prospective study of all children born before 32 weeks' gestation between 1 January 1990 and 31 December 1991 in a geographically defined population of approximately 3 million in the Northern Region of the United Kingdom. All children were examined aged 2 years by the same ophthalmologist and paediatrician.

RESULTS

558 children (98.6% of study group) were examined. Logistic regression showed an increased risk of strabismus in children with cicatricial retinopathy of prematurity (p=0.02), refractive error (p=0.003), family history of strabismus (p<0.0001), and poor neurodevelopmental outcome (p<0.0001), in particular impaired locomotor skills (p=0.008) and hand-eye coordination (p=0. 001). Gestational age and regressed acute ROP were not independent risk factors for strabismus (p=0.92 and 0.85 respectively).

CONCLUSIONS

This study has identified factors which are independently related to strabismus (although not necessarily causative) and others which are related only indirectly. This may contribute both to the management of children born prematurely and to future studies of the aetiology of strabismus.

Urinary excretion of pyridinium crosslinks in healthy 4-10 year olds

Urinary pyridinoline and deoxypyridinoline, pyridinium crosslinks released during breakdown of mature collagen, might serve as useful markers of bone resorption. Before their role can be identified, reference values must be established. In this study, free pyridinoline (f-Pyr), free deoxypyridinoline (f-DPyr), and creatinine (Cr) were measured in first morning void urine samples from 250 girls and 265 boys between the ages of 4 and 10 years. Overall, there was a decrease in f-Pyr:Cr and f-DPyr:Cr ratios with increasing age in both sexes, but there was a wide range of values for individuals of similar ages. Further studies are required to assess whether urinary pyridinium crosslink excretion is sufficiently deranged in conditions affecting bone metabolism for the measurement of these compounds to be of clinical value.

Evaluation of a new method for the analysis of free catecholamines in plasma using automated sample trace enrichment with dialysis and HPLC

BACKGROUND

Analysis of urinary free catecholamines was automated recently, but analysis of plasma samples posed special difficulties. The present study was undertaken to evaluate a new method for the automated analysis of plasma catecholamines.

METHODS

The procedure is based on an improved sample handling system that includes dialysis and sample clean-up on a strong cation trace-enrichment cartridge. The catecholamines norepinephrine, epinephrine, and dopamine are then separated by reversed-phase ion-pair chromatography and quantified by electrochemical detection.

RESULTS

Use of a 740- microL sample is required to give the catecholamine detection limit of 0.05 nmol/L and analytical imprecision (CV) between 1.1% and 9.3%. The assay can be run unattended, although >12 h of analysis time is not recommended without cooling of the autosampler rack. Comparison (n = 68) of the automated cation-exchange clean-up with the well-established manual alumina procedure gave excellent agreement (mean, 3.78 +/- 2.76 and 3.8 +/- 2.89 nmol/L for norepinephrine and 0.99 +/- 1.72 and 1.08 +/- 1.78 nmol/L for epinephrine). Hemodialysis had no clear effect on plasma norepinephrine. Epinephrine concentrations were similar (0.05 < P < 0.1) in chronic renal failure patients (0.24 +/- 0.3 nmol/L; n = 15) and healthy controls (0.5 +/- 0.24 nmol/L; n = 31). Dopamine was not quantified, being usually <0.2 nmol/L.

CONCLUSION

The availability of such a fully automated procedure should encourage the more widespread use of plasma catecholamine estimation, e.g., after dialysis, exercise, or trauma/surgery and in the investigation of catecholamine-secreting tumors, particularly in the anuric patient.

Pre-dialysis serum albumin is a poor indicator of nutritional status in stable chronic haemodialysis patients

The correlation between pre-dialysis serum albumin and mortality has been linked with malnutrition. We measured pre and post-dialysis albumin in 86 stable haemodialysis patients and compared them with anthropometric measurements and body mass index (BMI). On the basis of pre-dialysis albumin 13% of patients would be classified as high risk, whilst on the basis of post-dialysis albumin only 12% would be classified as high risk. Change in albumin could be predicted by fluid removal during haemodialysis. Pre-dialysis albumin correlated weakly with mid upper arm circumference (MUAC). Post dialysis albumin correlated with MUAC and triceps skin fold thickness (TSF). There was a weak negative correlation between age and post-dialysis albumin. TSF strongly correlated with MUAC and BMI. Pre-dialysis albumin appears to be a poor predictor of nutritional status and does not correlate well with other nutritional parameters. The excess risk of death associated with a low pre-dialysis albumin may be related to fluid overload rather than malnutrition.

Usefulness of pindolol in neurocardiogenic syncope

We prospectively studied the efficacy of pindolol, a beta-adrenergic blocker with intrinsic sympathomimetic activity (ISA), for the prevention of syncope recurrences in 31 patients with recurrent neurocardiogenic syncope. Pindolol proved to be an effective treatment, even in patients who had previously failed treatment with conventional beta blockers, suggesting a clinical benefit from addition of ISA to beta blockade in this setting.

The incorporation of lamotrigine into the routine automated sequential trace enrichment of dialysates assay of anticonvulsants

We have extended automated sequential trace enrichment of dialysates and high performance liquid chromatography to include the simultaneous assay of lamotrigine with other anticonvulsant drugs: phenobarbitone, carbamazepine and phenytoin. The procedure is reliable and precise (between-batch coefficients of variation < 2.8%) with no interference from other commonly prescribed drugs. Patients on lamotrigine presented with serum concentrations up to 67 mumol/L with no adverse effects, suggesting that the therapeutic range may need re-appraisal.

Refractive errors in children born before 32 weeks gestation

PURPOSE

To document the refractive errors in a cohort of children born before 32 weeks gestation.

METHODS

All children born before 32 weeks gestation between 1 January 1990 and 31 December 1991 to mothers resident in the Northern Region of the National Health Service were examined at 2 years old (n = 558).

RESULTS

Stage 3 or worse retinopathy of prematurity (ROP) was associated with myopia. In those not developing stage 3 or worse ROP, the refractive errors were myopia in 1.5%, hypermetropia > 4 dioptres (D) in 5.4%, anisometropia > 1 D in 1.1% and astigmatism > 1.25 D in 5.7%.

CONCLUSION

The incidence of refractive errors in those not developing stage 3 or worse ROP was similar to that in the general population.

The performance of an infra-red interactance instrument for assessing total body fat

Infra-red interactance has been evaluated as a technique for measuring total body fat in comparison with a range of alternative methods. The alternative techniques employed were neutron activation analysis, tritiated water dilution, whole-body potassium-40 counting, skinfold anthropometry, bioelectrical impedance analysis and the body mass index. The study group consisted of 43 healthy adults (16 males and 27 females). For 11 women, measurements were obtained before and after 11 weeks on a very low-calorie diet, giving a total of 54 sets of data. Correlation coefficients between infra-red interactance and the other techniques varied between 0.58 (p < 0.0002) and 0.80 (p < 0.0001) for females, and between 0.64 (p < 0.009) and 0.94 (p < 0.0001) for males. The average fat for the study group was underestimated by 15% using infra-red interactance in comparison with the average fat obtained from the other techniques. It was also noted that the infra-red interactance instrument yielded a very narrow range of body fats in females in comparison with the other techniques. It is essential that these differences are reconciled before infra-red interactance takes a significant role in body composition analysis.

Audit of 6 years' experience of breast fine needle aspiration (FNA) cytology using the cytospin method; improvement through multidisciplinary clinical audit

A breast FNA cytology service for palpable breast lumps was commenced in 1989 using the cytospin method. Over the following 6 years 2314 aspirates were received. The results were audited in detail in 1990, 1991/1992 and 1994. Multidisciplinary clinical audit meetings followed each audit cycle. Practice change was agreed after each audit. Each audit cycle was followed by demonstrable improvement in the complete sensitivity of the technique, being respectively 79%, 88% and 96%. The cytospin method is a viable alternative to the conventional smear method.

Reliability of rectal biopsy in distinguishing between chronic inflammatory bowel disease and acute self-limiting colitis

AIMS

In order to assess the validity of previously proposed criteria for the differentiation of chronic inflammatory bowel disease (CIBD) from acute self-limiting colitis (ASLC) all rectal biopsies were reported by a single histopathologist with a long-term gastrointestinal interest over a 4.5-year period.

METHODS AND RESULTS

The presence or absence of distorted crypt architecture, increased lymphocytes and plasma cells, villous mucosal architecture, granulomata, basal lymphoid aggregates, basal giant cells and Paneth cell metaplasia was noted for each biopsy. The definite presence of any of the above features, with the exception of intramucosal granulomata, was regarded as indicative of CIBD. Eighteen months later all available case notes were examined and the presenting clinical symptoms and working clinical diagnosis extracted. The final diagnosis, histopathological diagnosis and the presence or absence of any of the above histopathological features were correlated and the positive predictive value of each histopathological feature was calculated. A correct diagnosis of either CIBD or ASLC was made in 80 of 84 and 29 of 31 cases, respectively.

CONCLUSIONS

Villous mucosal architecture and Paneth cell metaplasia were found to be specific features of CIBD. Distorted crypt architecture, basal lymphoid aggregates and plasma cell infiltration of the lamina propria were also useful features but strict definition of these features is required and discussed. Intramucosal epithelioid granulomas were identified in eight cases of CIBD and four cases of ASLC. In association with ruptured crypts intramucosal granulomas are not specific features of Crohn's colitis.

Estimating social adjustment following spinal trauma--II: Population trends and effects of compensation on adjustment

Adaptation to, or acceptance of, acquired spinal cord injury is accepted as an essentially longitudinal process. Changes in an individual's social, financial and domestic positions in turn affect issues concerning quality of life and self-image. The responses of 302 individuals with spinal cord injury in the United Kingdom and United States of America are presented to produce individual profiles of social adjustment. The differences between the UK and USA groups are presented, together with a combined analysis which addresses, in particular, the effects which being involved in litigation has on the process of social adjustment. Individual data concerning social adjustment, provided through a scale developed by the authors, and the utility of graphical presentation of the data is also presented. Such presentation has been found to have particular importance in clinical interview, situations by providing a framework for further exploration of individual adjustment difficulties, and in legal settings.

Estimating social adjustment following spinal trauma--I: Who is more realistic--patient or spouse? A statistical justification

Whilst assessment of functional independence has been accomplished, to a greater extent, following spinal trauma, assessing social adjustment remains an area requiring considerable further investigation. Providing premorbid estimation of adjustment is an area which presents a number of methodological difficulties both in the collection and interpretational of longitudinal data. Such analyses tend to allow overall estimates of adjustment to be made but which lack individual specificity. Analyses are presented of over 250 individuals, and their closest relative's assessment, of social adjustment to their spinal cord injury. Using a modification of an established scale for assessing social adjustment it has been possible to establish the statistical level of agreement and address the hypothesis of differential perception of the extent of adjustment problems by the injured person and their closest relative. The study allows for the conclusion that an injured person's perception of adjustment is at least as reliable as their closest relative, and that there is further evidence to support the essential accuracy of their estimations of premorbid and current levels of adjustment. Both issues are of clinical importance, particularly in relation to any medico-legal compensation aspects.

Metaiodobenzylguanidine as an index of atrioventricular nodal adrenergic activity

Despite its importance, little is known about the uptake, storage and release of catecholamines in the atrioventricular (AV) node and His bundle. Previous in vitro studies have been limited by metabolism of norepinephrine. Metaiodobenzylguanidine (MIBG) shares many transport properties with norepinephrine and is considered a functional marker of adrenergic activity.

METHODS

We used [125I]MIBG +/- 99mTc-sestamibi (99mTc-MIBI) and [123I]MIBG +/- 201TI] to evaluate regional differences in adrenergic activity between cardiac conductive and contractile elements in rats. Histological localization of the AV node and His bundle was performed using stains for acetylcholinesterase.

RESULTS

Densitometric evaluation of autoradiographs, obtained from 20-mu thick sections of hearts from rats injected with either [125I]MIBG +/- 99mTc-MIBI (n = 4) and [123I]MIBG +/- 201TI (n = 6), revealed that there was approximately 30% more MIBG uptake in the AV node and His bundle compared to atrial or ventricular muscle (p < 0.05). Color-coded functional maps, generated by computer to simultaneously display 123I or [125I]MIBG and perfusion markers, revealed that the heterogeneous distribution of MIBG was independent of myocardial blood flow.

CONCLUSION

When used as a selective functional marker of adrenergic activity in the cardiac conduction system, 123I- or [125I]MIBG autoradiography demonstrates increased adrenergic activity in the AV node and His bundle compared with the left ventricle. MIBG imaging provides a new research technique to probe in vivo modulation of AV nodal and His bundle sympathetic activity.