Developing indicators and measures of high-quality for Australian general practice

BACKGROUND

Rising health costs and health inequity are major challenges in Australia, as internationally. Strong primary health care is well evidenced to address these challenges. Primary Health Networks (PHNs) work with general practices to collect data and support quality improvement; however, there is no consensus regarding what defines high quality. This paper describes the development of an evidence-based suite of indicators and measures of high-quality general practice for the Australian context.

METHODS

We reviewed the literature to develop a suitable framework and revise quality assurance measures currently in use, then reviewed these in three workshops with general practitioners, practice managers, nurses, consumers and PHN staff in western Sydney. We used a descriptive qualitative research approach to analyse the data.

RESULTS

A total of 125 evidence-based indicators were agreed to be relevant, and 80 were deemed both relevant and feasible. These were arranged across a framework based on the Quadruple Aim, and include structure, process and outcome measures.

CONCLUSIONS

The agreed suite of indicators and measures will be further validated in collaboration with PHNs across Australia. This work has the potential to inform health systems innovation both nationally and internationally.

Diabetes care and pregnancy outcomes for women with pregestational diabetes in Ireland

AIMS

Pre-gestational diabetes mellitus (PGDM) is associated with adverse outcomes. We aimed to examine pregnancies affected by PGDM; report on these pregnancy outcomes and compare outcomes for patients with type 1 versus type 2 diabetes mellitus; compare our findings to published Irish and United Kingdom (UK) data and identify potential areas for improvement.

METHODS

Between 2016 and 2018 information on 679 pregnancies from 415 women with type 1 Diabetes Mellitus and 244 women with type 2 diabetes was analysed. Data was collected on maternal characteristics; pregnancy preparation; glycaemic control; pregnancy related complications; foetal and maternal outcomes; unscheduled hospitalisations; congenital anomalies and perinatal deaths.

RESULTS

Only 15.9% of women were adequately prepared for pregnancy. Significant deficits were identified in availability and attendance at pre-pregnancy clinic, use of folic acid, attaining appropriate glycaemic targets and appropriate retinal screening. The majority of pregnancies (n = 567, 83.5%) resulted in a live birth but the large number of infants born large for gestational age (LGA) (n = 280, 49.4%), born prematurely <37 weeks and requiring neonatal intensive care unit (NICU) admission continue to be significant issues.

CONCLUSIONS

This retrospective cohort study identifies multiple targets for improvements in the provision of care to women with pre-gestational DM which are likely to translate into better pregnancy outcomes.

An Irish National Diabetes in Pregnancy Audit: aiming for best outcomes for women with diabetes

AIMS

The purpose of this study was to identify the number of pregnancies affected by pre-gestational diabetes in the Republic of Ireland; to report on pregnancy outcomes and to identify areas for improvement in care delivery and clinical outcomes.

METHODS

Healthcare professionals caring for women with pre-gestational diabetes during pregnancy were invited to participate in this retrospective study. Data pertaining to 185 pregnancies in women attending 15 antenatal centres nationally were collected and analysed. Included pregnancies had an estimated date of delivery between 1 January and 31 December 2015.

RESULTS

The cohort consisted of 122 (65.9%) women with Type 1 diabetes and 56 (30.3%) women with Type 2 diabetes. The remaining 7 (3.8%) pregnancies were to women with maturity-onset diabetes of the young (MODY) (n = 6) and post-transplant diabetes (n = 1). Overall women were poorly prepared for pregnancy and lapses in specific areas of service delivery including pre-pregnancy care and retinal screening were identified. The majority of pregnancies 156 (84.3%) resulted in a live birth. A total of 103 (65.5%) women had a caesarean delivery and 58 (36.9%) infants were large for gestational age.

CONCLUSIONS

This audit identifies clear areas for improvement in delivery of care for women with diabetes in the Republic of Ireland before and during pregnancy.

The Presentation and Diagnosis of the First Known Community-Transmitted Case of SARS-CoV-2 in the Republic of Ireland

Introduction This case series describes the diagnosis of the first case of community transmission of SARS-CoV-2 in the Republic of Ireland. Cases Case 1: A 25 year old male presented with dyspnoea, cough and high fevers for 4 days. He was commenced on broad-spectrum antimicrobials and oxygen therapy. His respiratory function deteriorated in spite of these measures and he required mechanical ventilation. CT showed left upper lobe consolidation as well as multifocal ground-glass opacification. Case 2: A 43 year-old male presented with headache and was found incidentally to have pneumonia. He was recently diagnosed with pituitary apoplexy secondary to an adenoma with resultant pituitary insufficiency but MRI brain was stable. His respiratory function deteriorated in spite of antibiotics and he required mechanical ventilation. CT showed likely atypical infection with resultant ARDS. Outcome Both underwent nasopharyngeal RT-PCR testing for SARS-CoV-2. Patient 2 was positive. Patient 1 was extubated and made a good recovery. Patient 2 was transferred to another centre for ECMO therapy. He died 27 days after transfer. Conclusion Given the atypical presentations in generally otherwise young and healthy individuals, the decision was made outside of national guidance to perform testing for SARS-CoV-2. This diagnosis had far-reaching implications for the SARS-CoV-2 pandemic within Ireland.

Experiences of primary healthcare professionals and patients from an area of urban disadvantage: a qualitative study

BACKGROUND

The health disadvantage in socioeconomically marginalised urban settings can be challenging for health professionals, but strong primary health care improves health equity and outcomes.

AIM

To understand challenges and identify needs in general practices in a socioeconomically marginalised Australian setting.

DESIGN & SETTING

Qualitative methodology with general practices in a disadvantaged area of western Sydney.

METHOD

Semi-structured interviews with healthcare professionals and their patients were transcribed and analysed thematically under the guidance of a reference group of stakeholder representatives.

RESULTS

A total of 57 participants from 17 practices (comprising 16 GPs, five GP registrars [GPRs], 15 practice staff, 10 patients, and 11 allied health professionals [AHPs]), provided a rich description of local communities and patients, and highlighted areas of satisfaction and challenges of providing high quality health care in this setting. Interviewees identified issues with health systems impacting on patients and healthcare professionals, and recommended healthcare reform. Team-based, patient-centred models of primary health care with remuneration for quality of care rather than patient throughput were strongly advocated, along with strategies to improve patient access to specialist care.

CONCLUSION

The needs of healthcare professionals and patients working and living in urban areas of disadvantage are not adequately addressed by the Australian health system. The authors recommend the implementation of local trials aimed at improving primary health care in areas of need, and wider health system reform in order to improve the health of those at socioeconomic and health disadvantage.

First reported case in Ireland of MEN2A due to a rare mutation in exon 8 of the RET oncogene

We present the case of a 30-year-old female who was diagnosed with hereditary phaeochromocytoma secondary to a rare gene mutation in exon 8 of the RET oncogene. This genetic mutation was picked up as part of an extended genetic screen using a method known as next generation sequencing. Detection of this genetic mutation prompted further screening for the manifestation of multiple endocrine neoplasia type 2A (MEN2A). The patient subsequently underwent a thyroidectomy with histology confirming C-cell hyperplasia.

Periodontitis and type 2 diabetes: is oxidative stress the mechanistic link?

Periodontitis is a common, chronic inflammatory disease initiated by bacteria which has an increased prevalence and severity in patients with type 2 diabetes. Recent studies indicate that the co-morbid presence of periodontitis can, in turn, adversely affect diabetic status and the treatment of periodontitis can lead to improved metabolic control in diabetes patients. Current evidence points to a bidirectional interrelationship between diabetes and inflammatory periodontitis. The importance of oxidative stress-inflammatory pathways in the pathogenesis of type 2 diabetes and periodontitis has recently received attention. Given the bidirectional relationship between these two conditions, this review discusses the potential synergistic interactions along the oxidative stress-inflammation axis common to both type 2 diabetes and periodontitis, and the implications of this relationship for diabetic patients.

ABLE - assessment based learning

Over the past decade the Australian health care system has moved rapidly toward a greater emphasis on medical care being provided within the community. This trend can only continue as our population ages and levels of chronic and complex illness continue to rise. Primary care now includes: a higher proportion of general practitioners working in group practices supported by practice nurses and allied health professionals- both on site and in the community, increased patient presentations for chronic and complex disease - often compounded by mental health and social issues, and, more hospital in the home, early discharge and similar programmes enabling shared management of sicker patients in the community.

Attitudes, awareness and oral health-related quality of life in patients with diabetes

The purpose of this study was to assess the knowledge diabetic patients have of their risk for periodontal disease, their attitude towards oral health and their oral health-related quality of life (OHRQL). One hundred and one consecutive patients (age range 31-79 years) recruited from a diabetic outpatient clinic participated in the study. Twenty-seven per cent of participants had type 1 diabetes, 66% type 2 and 7% did not know what type of diabetes they had. The length of time since participants were diagnosed as diabetic ranged from 1 to 48 years. Metabolic control of diabetes as determined by HbA1c levels ranged from 6.2% to 12.0% compared with the normal range of 4.5-6.0%. Thirty-three per cent of participants were aware of their increased risk for periodontal disease, 84% of their increased risk for heart disease, 98% for eye disease, 99% for circulatory problems and 94% for kidney disease. Half of the participants who were aware of their increased risk for periodontal disease had received this information from a dentist. Dental attendance was sporadic, with 43% reporting attendance within the last year. OHRQL was not significantly affected by the presence of diabetes in the group surveyed, in comparison with a previous survey of non-diabetic patients. A significant association was found between metabolic control and dentate status. Awareness of the potential associations between diabetes, oral health and general health needs to be increased in diabetic patients.

The cost of treating type 2 diabetes (CODEIRE)

Diabetes mellitus is the most common chronic metabolic disease and a major source of morbidity and mortality. Type 2 diabetes (T2D) is by far the most prevalent form of diabetes accounting for around 90% of cases worldwide. In recent years it has become apparent that a diabetes epidemic is unfolding as a result of increasing obesity, sedentary lifestyles and an ageing population. The enormity of the diabetes epidemic raises concern about the total cost to healthcare systems. This study was undertaken to investigate the direct healthcare costs of managing T2D in Ireland. Data was captured on 701 diabetes patients attending four diabetes centres. A bottom-up, prevalence-based design was used, which collected data on hospital resource use and clinical outcome measures over a 12-month period (1999/2000). The study was observational in nature, focusing on usual care of patients with T2D. Although the true prevalence of T2D in Ireland is unknown, conservative estimates are 3.9% for diagnosed diabetes and 6% for both diagnosed and undiagnosed diabetes. Using these figures the annual total direct cost was estimated at 377.2 million euro for diagnosed diabetes and 580.2 million euro for both diagnosed and undiagnosed diabetes. This corresponds to 4.1% and 6.4% of total healthcare expenditure respectively. Hospitalisations were the main driver of costs, accounting for almost half of overall costs, while ambulatory and drug costs accounted for 27% and 25% respectively. Hospitalisation costs were high because 60% of patients had developed complications. The most common microvascular and macrovascular complications were neuropathy and angina respectively. The annual cost of care for patients with microvascular and macrovascular complications were 1.8 and 2.9 times the cost of treating those without clinical evidence of complications respectively. The figure for patients with both types of complications was 3.8. This study shows that T2D is a very costly disease, largely due to the cost of and the management of complications. Many diabetes related complications are preventable, therefore it would appear a cost-effective approach for government to invest in the prevention of T2D and diabetes related complications.

Gastric electrical stimulation: a report of two cases

Gastroparesis refractory to prokinetic agents poses a major challenge to the physician and patient, alike. In the past 5 years, electrical methods to treat gastroparesis have emerged from animal and human experiments to a potentially valuable tool in clinical gastroenterology. One of these methods, known as gastric electrical stimulation (GES), is being increasingly used in specialized centres worldwide, but had never been tried in Ireland. We describe here our experience with the first two implantations of gastric neurostimulators performed in Ireland and the outcome with these 2 patients. Our results at 6 months show reduction in symptoms and improvement in quality of life, which is encouraging and should prompt further evaluation of GES for patients with gastroparesis refractory to medical therapy.

Prevalence and lifestyle determinants of the metabolic syndrome

Participants with the metabolic syndrome are at risk of developing type 2 diabetes and coronary heart disease. The aim of this study was to determine the role of lifestyle risk factors in the development of the metabolic syndrome with particular reference to physical activity, smoking and alcohol consumption. We performed a cross sectional study of the prevalence of CVD risk factors and glucose intolerance, including type 2 diabetes involving a group of 1473 men and women were sampled from 17 general practice lists in the South of Ireland. A total of 1018 attended for screening, giving a response rate of 69%. Participants completed a detailed health and lifestyle questionnaire and provided fasting blood samples for analysis of glucose, insulin and lipids. The metabolic syndrome was defined according to the current WHO criteria. The prevalence of the metabolic syndrome was 21.0% (95% C.I. 18.7% to 24.1%). In multivariate analyses with the metabolic syndrome as the dependent variable we observed a significant, independent inverse association with physical activity level (OR = 0.60; 95% CI, 0.39-0.90 for medium and OR = 0.51; 95% CI, 0.28-0.93) for high level of activity relative to the low level of activity group). Ex-drinkers had a higher prevalence of the syndrome in multivariate analysis relative to occasional drinkers, (OR = 2.38; 95% CI, 1.08-5.26). Prevalence of the metabolic syndrome was not significantly associated with current alcohol consumption or with smoking status. These data highlight the importance of physical inactivity in the aetiology of the metabolic syndrome.

Alcohol intake and insulin resistance. A cross-sectional study

BACKGROUND AND AIM

The development of insulin resistance is a critical step in the pathogenesis of type 2 diabetes. The effect of alcohol intake on insulin sensitivity/resistance is not well defined. The aim of this study was to examine the association between alcohol intake and insulin resistance in a sample of middle-aged men and women with data on a wide range of potential confounding factors, including diet.

METHODS

We performed a cross sectional study involving a group of 1018 men and women, sampled from 17 general practice lists in the South of Ireland, with a response rate of 69%. Participants completed a detailed health and lifestyle questionnaire and a food frequency questionnaire and provided fasting blood samples for analysis of glucose and insulin. Insulin resistance was estimated on the basis of fasting glucose and insulin, using the glucose homeostasis model (HOMA scores). Insulin resistance was defined as the upper quartile of the HOMA scores.

RESULTS

We found evidence of a U-shaped relationship between alcohol intake and insulin resistance fitted as a continuous variable (HOMA scores) with lowest levels in light drinkers (between 0.5 to 0.99 units per day) relative to the other drinking categories. However no significant association between alcohol intake and HOMA score was observed in fully adjusted analyses, including adjustment for dietary saturated fat and fruit and vegetables intake. In logistic regression analysis with insulin resistance (categorical) as the dependent variable, we observed that ex-drinkers were at higher risk of insulin resistance compared to occasional drinkers independently of age, sex, BMI and waist circumference, (OR=2.4, 95% CI, 1.1-5.7, p=0.04). On further adjustment for potential confounders including diet this association was also attenuated and was non-significant.

CONCLUSIONS

The reported effects of alcohol intake on insulin resistance may be confounded by other aspects of lifestyle, especially diet.

Rationalising the design of polymeric thermoresponsive biomaterials

We investigated the cell adhesion and growth of a series of thermoresponsive copolymers of N-isopropylacrylamide (NIPA) and N-tert-butylacrylamide (NtBA) above their lower critical solubility temperatures (LCST). It was found that cell adhesion and growth on the solvent cast films improved with increasing the NtBA content in the copolymers. The improvement was dependent on cell line. The surfaces of copolymers were analysed by atomic force microscopy. The topography of polymer films was not dependent on composition. The differences in the cell attachment and growth were attributed to the variation of surface energy with composition. The surface energy of copolymers decreased with the increase in the NtBA content. We conclude that poly(N-isopropylacrylamide) (poly(NIPA)) is a relatively poor substrate for cell growth and proliferation. However, its ability to support cell growth can be significantly improved by suitable modification.

Acromegaly and colorectal cancer: a comprehensive review of epidemiology, biological mechanisms, and clinical implications

Acromegaly is an endocrine disorder characterised by sustained hypersecretion of growth hormone (GH) with concomitant elevation of insulin-like growth factor (IGF)-I, and is associated with malignancy and premature mortality from cardiovascular and respiratory diseases. In particular, there may be an increased risk of colorectal neoplasia, but the exact extent of this is contentious. Colonoscopy-based studies of adenoma prevalence rates in acromegalic patients are misleading, but population-based studies on colorectal cancer risk are more consistent - a meta-analysis estimated a pooled risk ratio of 2.04 (95 % CI: 1.32, 3.14). Possible mechanisms underlying this increased risk include direct actions as a consequence of elevated levels of circulating GH and IGF-I and/or other perturbations within the IGF system. Other possible mechanisms include altered bile acid secretion, altered cellular immunity, hyperinsulinaemia, shared genetic susceptibility and increased bowel length. However, most explanations only offer indirect evidence, and the expectation of acromegaly as a natural model of colorectal carcinogenesis has not materialised. From a clinical perspective, it seems reasonable to consider a once-only colonoscopic screening at approximately age 55 years, but potential risks and benefits should be balanced.

Established cardiovascular disease and CVD risk factors in a primary care population of middle-aged Irish men and women

Contemporary Irish data on the prevalence of major cardiovascular disease (CVD) risk factors are sparse. The primary aims of this study were (1) to estimate the prevalence of major cardiovascular disease risk factors, including Type 2 Diabetes Mellitus, in the general population of men and women between the ages of 50 and 69 years; and (2) to estimate the proportion of individuals in this age group at high absolute risk of cardiovascular disease events on the basis of pre-existing cardiovascular disease or as defined by the Framingham equation. Participants were drawn from the practice lists of 17 general practices in Cork and Kerry using stratified random sampling. A total of 1018 people attended for screening (490 men, 48%) from 1473 who were invited, a response rate of 69.1%. Cardiovascular disease risk factors and glucose intolerance are common in the population of men and women aged between 50 and 69 years. Almost half the participants were overweight and a further quarter met current international criteria for obesity, one of the highest recorded prevalence rates for obesity in a European population sample. Forty per cent of the population reported minimal levels of physical activity and 19% were current cigarette smokers. Approximately half the sample had blood pressure readings consistent with international criteria for the diagnosis of hypertension, but only 38% of these individuals were known to be hypertensive. Eighty per cent of the population sample had a cholesterol concentration in excess of 5 mmol/l. Almost 4% of the population had Type 2 Diabetes Mellitus, of whom 30% were previously undiagnosed. A total of 137 participants (13.5%) had a history or ECG findings consistent with established cardiovascular disease. Of the remaining 881 individuals in the primary prevention population, a total of 20 high-risk individuals (19 male) had a risk of a coronary heart disease event > or = 30% over ten years according to the Framingham risk equation, giving an overall population prevalence of 2.0% (95% CI 1.3 - 3.0). At a risk level > or = 20% over ten years, an additional 91 individuals (8.9%) were identified. Thus a total of 24.4% of the population were at risk either through pre-existing CVD (13.5%) or an estimated 10-year risk exceeding 20% according to the Framingham risk equation (10.9%). Thus a substantial proportion of middle-aged men are at high risk of CVD. The findings emphasise the scale of the CVD epidemic in Ireland and the need for ongoing monitoring of risk factors at the population level and the need to develop preventive strategies at both the clinical and societal level.

Circulating insulin-like growth factor II and colorectal adenomas

Circulating insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) may be risk factors for the development of colorectal cancer. On the other hand, IGF-II and IGFBP-2 are overexpressed in colorectal carcinomas. These contrasting backgrounds led us to investigate the relationship between serum IGF-I, IGF-II, IGFBP-2, and IGFBP-3 and the presence of colorectal adenomas, known precursors of colorectal carcinoma, in 345 volunteers attending a screening flexible sigmoidoscopy trial (entry criteria: healthy, aged 55-64 yr). The most striking finding was an elevated mean serum IGF-II in individuals with adenomas (n = 52) compared with controls (mean difference, 139 ng/mL; 95% confidence intervals, 82, 196; P < 0.0001). Logistic regression adjusting for confounding factors confirmed the significant association between IGF-II and adenoma occurrence (P < 0.0001) and revealed an additional positive association with serum IGFBP-2 (P < 0.0001). However, there was no association found between either serum IGF-I and/or IGFBP-3 and the presence of adenomas. Additionally, in 31 individuals with adenomas in whom levels were determined pre- and postpolypectomy, there was a significant fall in mean IGF-II (P < 0.001) and IGFBP-2 (P < 0.001) after adenoma removal, but no difference in IGF-II and IGFBP-2 concentrations between repeated samples in 20 individuals without adenomas. Immunohistochemical studies demonstrated IGF-II expression in 83% of all adenomas, which contrasted with absent expression in normal colonic expression and hyperplastic polyps. This study has shown for the first time that serum IGF-II may be a tumor marker in individuals with colorectal adenomas. Further studies are needed to validate these relationships in larger populations, including individuals undergoing colonoscopy.

Evaluation of standard haemodynamic tests of autonomic function and HbA1c as predictors of delayed gastric emptying in patients with type 1 diabetes mellitus

We examined the relation between chronic glycaemic control (using glycosylated haemoglobin), haemodynamic autonomic function and rate of gastric emptying in 16 patients with type 1 diabetes mellitus. Gastric emptying was measured using a paracetamol absorption technique. Parameters of gastric emptying include area under the plasma paracetamol concentration time curve. Patients were classified as diabetic autonomic neuropathy positive or negative using five standardized haemodynamic reflex tests. Area under the plasma paracetamol concentration time curve in the neuropathy positive (10.36 (4.5) mmol.-1. min) and negative (9.84 (3.0) mmol.-1. min) groups were similar (.P.=0.42) using unpaired Student's.t. -tests. Glycosylated haemoglobin concentration and area under the plasma paracetamol concentration time curve (.n.=16) demonstrated a Pearson's correlation co-efficient of 0.24. Neither tests of haemodynamic autonomic function, nor concentration of glycosylated haemoglobin, are predictive of diabetic gastroparesis.

Clinical studies of multiple endocrine neoplasia type 1 (MEN1)

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterized by the combined occurrence of parathyroid, pancreatic islet and anterior pituitary tumours. To facilitate a screening programme for MEN1, we investigated 709 people (364 males and 345 females, age range 1-84 years) from 62 MEN1 families, and 36 non-familial MEN1 patients. Of those investigated, 220 (95 males and 125 females, age range 8-79 years) suffered from MEN1. Parathyroid, pancreatic and pituitary tumours occurred in 95%, 41% and 30% of the patients, respectively. Parathyroid tumours were the first manifestation of MEN1 in 87% of patients, and amongst the pituitary and pancreatic tumours, somatotrophinomas and gastrinomas were more common in patients above the age of 40 years, whilst insulinomas occurred more frequently in patients below the age of 40 years. Biochemical screening indicated that the penetrance of MEN1 by the ages of 20, 35 and 50 years was 43%, 85% and 94%, respectively, and that the development of MEN1 was confined to first-degree relatives in 91% of patients and to second-degree relatives in 9% of patients. These findings have helped to define a proposed screening programme for MEN1.

11 beta-Hydroxysteroid dehydrogenase activity in Cushing's syndrome: explaining the mineralocorticoid excess state of the ectopic adrenocorticotropin syndrome

A characteristic feature of the ectopic ACTH syndrome is a state of mineralocorticoid excess, although the etiology remains obscure. Some forms of endocrine hypertension, such as licorice ingestion, have been explained by cortisol acting as a mineralocorticoid in the setting of inhibition or deficiency of 11 beta-hydroxysteroid dehydrogenase (11 beta HSD). This enzyme is responsible for the conversion of cortisol (F) to hormonally inactive cortisone, and its activity in vivo can be inferred from the ratio of the urinary excretion of tetrahydrocortisol (THF) and its isomer (5 alpha THF) to tetrahydrocortisone. Twenty-two patients with Cushing's syndrome (11 pituitary dependent, 9 ectopic, and 2 adrenal adenomas) and 13 controls were studied. Compared to controls. Cushing's patients had a significant increase (P < 0.001) in the excretion of all principal metabolites of F, secondary to a 5- to 6-fold increase in the cortisol secretion rate [median, 34.0 (range, 13.3-327) mg/day in Cushing's vs. 6.1 (range, 2.5-10.3) mg/day in controls]. The THF plus 5 alpha THF/tetrahydrocortisone ratio was significantly increased in Cushing's syndrome regardless of etiology [mean, 1.81 (range, 1.09-9.99) in Cushing's vs. 0.81 (range, 0.51-1.47) in controls; P < 0.001), indicative of defective 11 beta HSD activity. Furthermore, compared to patients with pituitary-dependent Cushing's, this ratio was significantly higher in patients with the ectopic ACTH syndrome (4.12 vs. 1.49; P < 0.01) and was inversely correlated with serum potassium levels (r = -0.57; P = 0.01; n = 22). One explanation for the mineralocorticoid excess state of the ectopic ACTH syndrome appears to be that cortisol gains inappropriate access to the mineralocorticoid receptor through failure of its normal metabolism by 11 beta HSD. The reason for the defective 11 beta HSD activity is unclear, but it may be secondary to substrate saturation, inhibition by other adrenal steroids, or product inhibition.

Evidence for neuropeptide Y synthesis in the rat anterior pituitary and the influence of thyroid hormone status: comparison with vasoactive intestinal peptide, substance P, and neurotensin

Neuropeptide Y (NPY), a 36-amino acid member of the pancreatic polypeptide family, was found to be present by RIA and immunocytochemistry in the rat anterior pituitary gland. NPY prohormone messenger RNA (mRNA) was identified in the pituitary by Northern blot analysis. The possible regulation of NPY was examined by determining the effects of thyroid hormone manipulation on peptide synthesis. Three other anterior pituitary neuropeptides, neurotensin (NT), substance P (SP), and vasoactive intestinal peptide (VIP), were studied for comparison. Hypothyroidism was found to significantly increase the pituitary content of NPY, SP, and VIP and their respective mRNAs but to decrease the quantity of NT. Immunocytochemistry revealed very weak NPY immunoreactivity in scattered cells in control rat anterior pituitaries, but in hypothyroid rats a greater number of positive cells were seen, and the staining was relatively intense. These positive cells were identified as a subset of thyrotropes. In T4-induced hyperthyroidism NPY, NT, and VIP levels were unaffected whereas SP concentrations fell considerably. TRH treatment produced a decrease in NT and had no effect on NPY, SP, or VIP. These changes were found only in the pituitary; no net change occurred in hypothalamic peptide and mRNA levels. Since the changes in pituitary peptide and mRNA levels occurred coordinately it appears that regulation by thyroid hormone status occurs, at least in part, directly at the level of gene transcription. The changes in these 4 regulatory peptides in hypothyroidism and their known powerful effects on pituitary function suggest that they may have a significant paracrine or autocrine influence in controlling the alterations in pituitary secretion.

Investigation of aminoglycoside nephrotoxicity in cystic fibrosis patients

Cystic fibrosis patients are a special risk group for nephrotoxic effects of amino-glycosides (AG). The traditional methods of assessing renal damage are very insensitive, and toxicity is not detected until serious functional damage is evident. The aims of the present study were to monitor early markers of nephrotoxicity in cystic fibrosis patients treated with gentamicin. Urinary excretion of beta-N-acetylglucosaminase (beta-NAG, a lysosomal enzyme) and low molecular weight proteins as identified on sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) were prospectively studied in cystic fibrosis outpatients and inpatients. Urinary excretions of beta-NAG and low molecular weight proteins were normal in cystic fibrosis patients not being treated with gentamicin. All patients being treated with intravenous gentamicin (average dose, 2.5 g over 9 days) showed markedly elevated urinary excretion of beta-NAG. SDS-PAGE of serial urine samples from CF patients during intravenous AG therapy showed increasing excretion of low molecular weight proteins. Protein excretion profiles from control subjects showed no change over equivalent time periods. CF patients receiving nebulized AG did not show altered protein excretion. beta-NAG excretion patterns were similar to changes detected in the SDS-PAGE system. No gross nephrotoxicity developed in these patients. Blood urea nitrogen, plasma creatinine, and plasma magnesium concentrations remained within normal limits. The pattern of protein excretion on SDS-PAGE was consistent with renal tubular rather than glomerular damage. The SDS-PAGE system provides an additional means of monitoring early subclinical nephrotoxicity of AG in CF patients.