Hospital Outcomes in Patients Hospitalized for COVID-19 Pneumonia: The Effect of SARS-CoV-2 Vaccination and Vitamin D Status

SARS-CoV-2 vaccination promises to improve outcomes for patients with COVID-19 pneumonia (most notably those with advanced age and at high risk for severe disease). Here, we examine serum 25-Hydroxyvitamin D (25(OH)D) status and outcomes in both old (>70 years) and young vaccinated (n = 80) and unvaccinated (n = 91) subjects, who were hospitalized due to COVID-19 pneumonia in a single center (Connolly Hospital Dublin). Outcomes included ICU admission and mortality. Serum 25(OH)D levels were categorized as D30 (<30 nmol/L), D40 (30-49.99 nmol/L) and D50 (≥50 nmol/L). In multivariate analyses, D30 was independently associated with ICU admission (OR: 6.87 (95% CI: 1.13-41.85) (p = 0.036)) and mortality (OR: 24.81 (95% CI: 1.57-392.1) (p = 0.023)) in unvaccinated patients, even after adjustment for major confounders including age, sex, obesity and pre-existing diabetes mellitus. While mortality was consistently higher in all categories of patients over 70 years of age, the highest observed mortality rate of 50%, seen in patients over 70 years with a low vitamin D state (D30), appeared to be almost completely corrected by either vaccination, or having a higher vitamin D state, i.e., mortality was 14% for vaccinated patients over 70 years with D30 and 16% for unvaccinated patients over 70 years with a 25(OH)D level greater than 30 nmol/L. We observe that high mortality from COVID-19 pneumonia occurs in older patients, especially those who are unvaccinated or have a low vitamin D state. Recent vaccination or having a high vitamin D status are both associated with reduced mortality, although these effects do not fully mitigate the mortality risk associated with advanced age.

Active management of hyponatraemia and mortality in older hospitalised patients compared with younger patients: results of a prospective cohort study

INTRODUCTION

Hyponatraemia is associated with increased morbidity and mortality; the aetiology and outcomes of hyponatraemia in older patients have not been defined in prospective studies.

METHODS

A single-centre 9-month prospective observational study in which clinical outcomes in hospitalised patients ≥ 65 years (older patients with hyponatraemia (OP-HN)) and those <65 years (young patients with hyponatraemia (YP-HN)) with hyponatraemia were analysed, and compared with eunatraemic controls (older patients with normonatraemia (OP-NN) and young patients with normonatraemia (YP-NN)).

RESULTS

In total, 1,321 episodes of hyponatraemia in 1,086 patients were included; 437 YP-HN, median age 54 years (IQR 44,60) and 884 OP-HN, median age 77 years (IQR 71,82). A total of 1,120 consecutive eunatraemic control patients were simultaneously recruited; 690 OP-NN, median age 77 years (IQR 71,83) and 430 YP-NN, median age 52 years (IQR 41,58). Euvolaemic hyponatraemia was the commonest cause of hyponatraemia in both age groups (48% in YP-HN and 46% in OP-HN). Sixty-two percent of OP-HN received hyponatraemia-directed treatment within the initial 48 h, compared with 55% of YP-HN, P = 0.01. Despite the greater treatment rates in OP-HN, younger patients were 24% more likely to be discharged with normal plasma sodium concentration (pNa) compared with older patients, relative risk (RR) 1.24 (95% confidence interval (CI) 1.12-1.37), P < 0.001.Using OP-NN as the reference group, the RR of in-hospital death in OP-HN was 2.15 (95% CI 1.3-3.56), P = 0.002. Using YP-NN as the reference group, the RR of in-hospital death in YP-HN was 4.34 (95% CI 1.98-9.56), P < 0.001.

CONCLUSION

Despite greater rates of HN-targeted treatment, the risk of in-hospital death is increased in older hyponatraemic patients compared with older eunatraemic controls. The impact of hyponatraemia on mortality is even greater in younger patients.

The effects of acute hyponatraemia on bone turnover in patients with subarachnoid haemorrhage: A preliminary report

CONTEXT

Animal data and cross-sectional human studies have established that chronic hyponatraemia predisposes to osteoporosis; the effects of acute hyponatraemia on bone turnover have not been determined. Our objective was to test the hypothesis that acute hyponatraemia leads to dynamic effects on bone turnover.

DESIGN

A prospective observational pilot study.

METHODS

Bone turnover markers [C-terminal crosslinking telopeptide of type 1 collagen (CTX-1), N-propeptide of type 1 collagen (P1NP) and osteocalcin] were measured prospectively over one week in 22 eunatraemic patients with subarachnoid haemorrhage. Patients treated with glucocorticoids were excluded.

RESULTS

Eight patients developed acute hyponatraemia, median nadir plasma sodium concentration 131 mmol/L (IQR 128-132), and 14 remained eunatraemic, nadir plasma sodium concentration 136 mmol/L (IQR 133-137). Significant main effects of hyponatraemia were found for P1NP (p = .02) and P1NP:CTX-1 ratio (p = .02), both fell in patients with acute hyponatraemia, with significant interaction between hyponatraemia and time from baseline for P1NP (p = .02). Significant main effects of time from baseline (p < .001) but not hyponatraemia (p = .07) were found for osteocalcin. For CTX-1, significant main effects of time from baseline (p = .001) but not hyponatraemia (p = .65) were found. There was a positive correlation between change in P1NP:CTX-1 ratio and nadir plasma sodium concentration, r = +.43, p = .04. Median serum cortisol (measured on days 1, 3 and 7) was higher in the hyponatraemia group than in those who remained eunatraemic, 545 nmol/L (IQR 373-778) versus 444 nmol/L (IQR 379-542) p = .03.

CONCLUSION

These data suggest that acute mild hyponatraemia is associated with a reduction in bone formation activity.

Active management of severe hyponatraemia is associated with improved mortality

OBJECTIVE

Severe hyponatraemia (plasma sodium concentration, pNa <120 mmol/L) is reported to be associated with mortality rates as high as 50%. Although there are several international guidelines for the management of severe hyponatraemia, there are few data on the impact of treatment.

DESIGN AND METHODS

We have longitudinally reviewed rates of specialist input, active management of hyponatraemia, treatment outcomes and mortality rates in patients with severe hyponatraemia (pNa <120 mmol/L) in 2005, 2010 and 2015, and compared the recent mortality rate with that of patients with pNa 120-125 mmol/L.

RESULTS

Between 2005 and 2010 there was a doubling in the rate of specialist referral (32 to 68%, P = 0.003) and an increase in the use of active management of hyponatraemia in patients with pNa <120 mmol/L (63 to 88%, P = 0.02), associated with a reduction in mortality from 51 to 15% (P < 0.001). The improved rates of intervention were maintained between 2010 and 2015, but there was no further reduction in mortality. When data from all three reviews were pooled, specialist consultation in patients with pNa <120 mmol/L was associated with a 91% reduction in mortality risk, RR 0.09 (95% CI: 0.03-0.26), P < 0.001. Log-rank testing on in-hospital survival in 2015 found no significant difference between patients with pNa <120 mmol/L and pNa 120-125 mmol/L (P = 0.56).

CONCLUSION

Dedicated specialist input and active management of severe hyponatraemia are associated with a reduction in mortality, to rates comparable with moderate hyponatraemia.

Fluid Restriction Therapy for Chronic SIAD; Results of a Prospective Randomized Controlled Trial

CONTEXT

Fluid restriction (FR) is the recommended first-line treatment for syndrome of inappropriate antidiuresis (SIAD), despite the lack of prospective data to support its efficacy.

DESIGN

A prospective nonblinded randomized controlled trial of FR versus no treatment in chronic SIAD.

INTERVENTIONS AND OUTCOME

A total of 46 patients with chronic asymptomatic SIAD were randomized to either FR (1 liter/day) or no specific hyponatremia treatment (NoTx) for 1 month. The primary endpoints were change in plasma sodium concentration (pNa) at days 4 and 30.

RESULTS

Median baseline pNa was similar in the 2 groups [127 mmol/L (interquartile range [IQR] 126-129) FR and 128 mmol/L (IQR 126-129) NoTx, P = 0.36]. PNa rose by 3 mmol/L (IQR 2-4) after 3 days FR, compared with 1 mmol/L (IQR 0-3) NoTx, P = 0.005. There was minimal additional rise in pNa by day 30; median pNa increased from baseline by 4 mmol/L (IQR 2-6) in FR, compared with 1 mmol/L (IQR 0-1) NoTx, P = 0.04. After 3 days, 17% of FR had a rise in pNa of ≥5 mmol/L, compared with 4% NoTx, RR 4.0 (95% CI 0.66-25.69), P = 0.35. After 3 days, 61% of FR corrected pNa to ≥130 mmol/L, compared with 39% of NoTx, RR 1.56 (95% CI 0.87-2.94), P = 0.24.

CONCLUSION

FR induces a modest early rise in pNa in patients with chronic SIAD, with minimal additional rise thereafter, and it is well-tolerated. More than one-third of patients fail to reach a pNa ≥130 mmol/L after 3 days of FR, emphasizing the clinical need for additional therapies for SIAD in some patients.

COVID-19 in adults: test menu for hospital blood science laboratories

Introduction

Coronavirus disease 2019 (COVID-19), is a respiratory illness caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The Clinical Blood Sciences Laboratory (CBSL) plays a key role in supporting the monitoring and management of patients with COVID-19 disease.

Objective

To provide a comprehensive CBSL testing protocol to support the medical management of SARS-CoV-2 infection.

Methods

Description of the biochemical, haematological and immunological tests that have a role in the assessment and monitoring of patients with COVID-19 infection.

Results

We provide a test menu for clinical laboratories to ensure the effective monitoring, management and prognostication of COVID-19 patients in hospital.

Conclusion

Given the rapidity with which patients with COVID-19 disease can deteriorate, we recommend regular testing with vigilance paid to the rate and trajectory of change in each of these parameters.

Oxycodone in Palliative Care-Art and Empathy Still Have a Place

A 47-year-old woman who was receiving palliative care for metastatic breast cancer, which included oxycodone, was found dead in bed. The femoral blood level of oxycodone at autopsy was 1200 µg/L, which is a value within the lethal range. Could the cause of death be attributed to misadventure or suicide? Would the coroner consider a recommendation of therapeutic drug monitoring in palliative care which could have a serious negative impact on pain relief practice? A narrative verdict was the outcome linking the primary cause of death with the drug cocktail found at autopsy.

Cerebrospinal fluid protein and glucose examinations and tuberculosis: Will laboratory safety regulations force a change of practice?

Cerebrospinal fluid (CSF) protein and glucose examinations are usually performed in chemical pathology departments on autoanalysers. Tuberculosis (TB) is a group 3 biological agent under Directive 2000/54/EC of the European Parliament but in the biochemistry laboratory, no extra precautions are taken in its analysis in possible TB cases. The issue of laboratory practice and safety in the biochemical analyses of CSF specimens, when tuberculosis infection is in question is addressed in the context of ambiguity in the implementation of current national and international health and safety regulations. Additional protective measures for laboratory staff during the analysis of CSF TB samples should force a change in current laboratory practice and become a regulatory issue under ISO 15189. Annual Mantoux skin test or an interferon-γ release assay for TB should be mandatory for relevant staff. This manuscript addresses the issue of biochemistry laboratory practice and safety in the biochemical analyses of CSF specimens when tuberculosis infection is in question in the context of the ambiguity of statutory health and safety regulations.

The spectrum of expert reports on clinical biochemical toxicology and medicine from an Irish practice

The compounds which generated an expert opinion report in the area of medical toxicology in the period 1999 to 2015 are presented from the toxicological case files of a specialist in chemical pathology and general internal medicine. There were 132 different compounds from 86 cases. Alcohol was involved in 43%, drugs of abuse in 18.6%, volatile carbon compounds in 17.4%, metals in 9.3%, and carbon monoxide in 4.6%. Many compounds appeared once. The duty of the medical expert witness to provide an objective report for the court irrespective of the payer is stated. The addition of references from peer reviewed literature to substantiate the pros and cons of each case is recommended as a standard operating procedure in completing each report.

Fault lines in forensic medical toxicology in Ireland exposed through replies of pathologists and coroners to anonymous questionnaires

The attitudes and experiences of pathologists and coroners to the provision of biochemical forensic toxicology in the Republic of Ireland were determined using separate questionnaires to each group anonymously. Replies were received from 36/88 (41%) of pathologists and 19/71 (27%) of coroners. 37% of coroners considered that histopathologists give an adequate opinion in forensic toxicology yet 58% of pathologists reported that they did not have adequate access to expert medical interpretative toxicological opinion. For drug-drug interactions and metabolic diseases, 69% of pathologists were unhappy with the processes and 68% of coroner replies did not know if vitreous samples were used appropriately. There is a clear requirement for retraining of coroners and for the appointment of medical toxicology expertise to improve the quality of service for coroners.

The complexity of PSA interpretation in clinical practice

Prostate specific antigen (PSA) is central to the diagnosis of prostate cancer. Laboratories quote cut-off reference ranges for PSA but values within these boundaries do not equate with an absence of cancer nor do levels above the range equate with its presence. Convention places the cut-off value at 4 μg/L when calibrated to the Hybritech immunoassay technology and 3.0 or 3.1 μg/L if the PSA methods are calibrated to the WHO IRP 96/670 standard. The prevalence of prostate cancer in screened normal men over 55 years of age with PSA values less than 4 μg/L (Hybritech method) is 10.1% at a PSA of 0.6-1.0 μg/L. About 12.5% of these will be high grade. Two major randomised trials reported on PSA screening. The European trial (ERSPC) reported a risk reduction for prostate cancer death of 21% in the screened group but the US PLCO trial found no benefit. PSA results depend on calibration and there is a 22% difference between the older Hybritech and newer WHO standardisation. Biological variation in PSA is a geometric mean of 7.3%. External quality assessment schemes show wide variation in the performance of PSA analysis. Neither the American College of Physicians nor the UK National Health Service recommends screening except when there is increased risk through family history or ethnicity. Laboratories should detail their method calibration in each report and clinicians should be alerted to the potential misclassification of patients through PSA variation.

Proposing and developing a National Institute for Forensic Toxicology in Ireland - transformation through education

Toxicology for coroners is an important minority service whose quality is central to the validity and integrity of the death certification system. Multidisciplinary case conferences are routine practice in the major medical specialties. In conventional practice for the coroners’ courts, the dissecting pathologist is often relied upon to interpret toxicological data usually without specialist training. In Ireland the service is fragmented and there is at present no medically trained toxicologist directly involved in the direction or reporting of cases even where multiple drugs are found in blood at various levels and drug-drug interaction may be possible or likely. To encourage both medical professionals and political administration to confront the issues, the education literature on action research and critical incident methodology is reviewed to develop a strategy for change in this service. An example of action research being applied to medicine is used as an indicator that an action research template could be used to advocate for a new National Institute for Forensic Toxicology in Ireland. The main participant groups are identified and the development cycle outlined.

Methadone, codeine and acute haemorrhagic necrotising pancreatitis: which came first?

Acute haemorrhagic necrotising pancreatitis lead to the death at home of a young female who was on a methadone maintenance programme. Toxic levels of codeine with potentially lethal levels of methadone and morphine were found at post-mortem. Whether opiates caused the pancreatitis or were the consequence of self-medication for pain is impossible to differentiate. Forensic toxicology may pose the question but be unable to provide the answer.

B-type natriuretic peptide in the cardiology department

Heart Failure is one of the fastest growing cardiovascular diseases of the 21st century. Echocardiogram is considered the gold standard for diagnosis, but is costly, time consuming and not readily accessible to all patients. Our aim was to assess the diagnostic utility of BNP to risk stratify patients for ECHO. Seventy-four GP referred, non-pregnant patients of > or = 18 years with a working diagnosis of HF were recruited. Patients were given two appointments to attend the Cardiology Department and at each, were examined by the same cardiologist, had their medications recorded and blood drawn for BNP analysis. ECHO was performed at the second visit. The diagnosis of HF was confirmed in 49 of 74 patients (66%). The clinical utility of BNP to rule-in HF was evaluated using ROC curve analysis. The AUC was satisfactory at 0.691 (C.I. 0.573-0.793). The positive likelihood ratio (+LR) was 5.87, negative likelihood ratio (-LR) was 0.58, the positive predictive value was 92% and a negative predictive value was 47%. One-third of patients (n = 25) had a BNP >178 pg/mL, 23 of whom had HF confirmed. At this decision threshold BNP correctly classified 23 of 25 patients who were confirmed not to have HF (Specificity for HF of 92%). A BNP of > or = 178 pg/mL can be used to prioritise GP patients for ECHO.

Poisonings and clinical toxicology: a template for Ireland

BACKGROUND

Poisons information is accessed around the clock in the British Isles from six centres of which two are in Ireland at Dublin and Belfast accompanied by consultant toxicologist advisory service. The numbers of calls in Ireland are down to about 40 per day due to easy access to online data bases. Access to Toxbase, the clinical toxicology database of the National Poisons Information Service is available to National Health Service (NHS) health professionals and to Emergency Departments and Intensive Care units in the Republic of Ireland. There are 59 Toxbase users in the Republic of Ireland and 99 % of activity originates in Emergency Departments. All United States Poison Control Centres primarily use Poisindex which is a commercial database from Thomson Reuters.

RESULTS

Information on paracetamol, diazepam, analgesics and psycho-active compounds are the commonest queries. Data from telephone and computer accesses provide an indicator of future trends in both licit and illicit drug poisons which may direct laboratory analytical service developments. Data from National Drug-Related Deaths Index is the most accurate information on toxicological deaths in Ireland. Laboratory toxicology requirements to support emergency departments are listed.

CONCLUSIONS

Recommendations are made for a web-based open access Toxbase or equivalent; for a co-location of poisons information and laboratory clinical toxicology; for the establishment of a National Clinical Toxicology Institute for Ireland; for a list of accredited medical advisors in clinical toxicology; for multidisciplinary case conferences in complex toxicology cases for coroners; for the establishment of a national clinical toxicology referral out-patients service in Ireland.

Atrial natriuretic peptide increases urinary albumin excretion in people with normoalbuminuric type-2 diabetes

BACKGROUND

Atrial natriuretic peptide (ANP) is elevated in patients with type-2 diabetes and microalbuminuria. The purpose of this study is to evaluate if ANP increases Urinary Albumin Eaxcretion Rate (UAER) in type-2 diabetes.

METHODS

Eight normoalbuminuric diabetic subjects underwent a randomised single blind study of 60 min intravenous infusion of ANP or vehicle. Eight non-diabetic controls underwent ANP infusion alone. Seven normoalbuminuric type-2 diabetes subjects received further ANP infusions during euglycaemia and during hyperglycaemia.

RESULTS

ANP increased urinary sodium (191.3 +/- 80.7 to 529.2 +/- 263.4 mumol/min, mean +/- SD, and P < 0.001) and UAER (72.2 +/- 73.4 to 224.9 +/- 182.9.5 mug/min, and P < 0.01) in diabetic subjects. In controls, UAER did not change significantly (P = 0.16); however, the natriuretic response to ANP was similar to diabetic subjects (P = 0.98). Hyperglycaemic did not enhance the albuminuric response to ANP (P = 0.88).

CONCLUSION

ANP increases UAER in normoalbuminuric type-2 diabetic subjects.

The albuminuric action of atrial natriuretic peptide is not modified by ACE-inhibition with perindopril in Type 2 diabetes

AIMS

Atrial natriuretic peptide (ANP) increases urine albumin excretion (UAER) in humans with Type 1 diabetes. The aim of this study was to establish if ANP increases UAER in microalbuminuric subjects with Type 2 diabetes and to examine whether the albuminuric action of ANP was inhibited by pre-treatment with the ACE-inhibitor perindopril.

METHODS

Seven microalbuminuric, normotensive males with Type 2 diabetes were entered into a randomised, double-blind, three-armed study of (i) intravenous infusion of ANP (0.25 microg/kg/min in 0.9% NaCl) after 3 weeks' pre-treatment with placebo, (ii) intravenous infusion of vehicle (0.9% NaCl only) after 3 weeks' pre-treatment with placebo, or (3) intravenous infusion of ANP (0.25 microg/kg/min in 0.9% NaCl) after 3 weeks' pre-treatment with perindopril, 4 mg daily.

RESULTS

Baseline parameters were similar on all three study days. During the placebo/vehicle arm there was no change in urine flow rate (UFR, P=0.61), urine cyclic guanosine monophosphate (UcGMP P=0.48) or UAER (P=0.99). During the placebo/ANP arm there was a rise in UFR [13.7+/-2.8 (mean+/-sd) to 25.7+/-7.7 mL/min, P<0.001], UcGMP (60.0+/-36.6 to 160.8+/-118.5 micromol/mmolCr, P=0.045) and UAER [5.13 [2.4-11.6][median (range)] to 71.6 [21.6-175.1] mg/mmolCr, P<0.001]. Pre-treatment with perindopril did not alter the changes in UFR (P=0.63), UcGMP (P=0.46) or UAER (P=0.99) to infusion of ANP, compared with the placebo/ANP arm.

CONCLUSION

ANP increases UAER in microalbuminuric patients with Type 2 diabetes and the albuminuric action of ANP is not inhibited by pre-treatment with the ACE inhibitor perindopril.

Twelve-year experience in the investigation and treatment of paragangliomas

We report a 12-year laboratory experience in the diagnosis of 37 patients with phaeochromocytoma, one with malignant paraganglioma and one with ganglioneuroblastoma. Surgery was performed in eight different hospitals, which underlines the difficulty of ensuring uniformity of investigations. Of the 37 with phaeochromocytoma, 15 were in the right adrenal gland, 12 were on the left, seven were bilateral and three were extra adrenal. Twenty-three were male and 15 were female; the median age was 36 years. Four of five patients with von Hippel-Lindau disease had bilateral adrenal tumours and four had neurofibromatosis. None had multiple endocrine neoplasia. Using essential hypertensive patients as a reference population, diagnostic sensitivity was 80% for noradrenaline, 54.4% for adrenaline, 19.1% for dopamine, 93.3% for total normetanephrine, 33.3% for total metanephrine, 78.7% for 3-methoxy-4-hydroxymandelic acid (HMMA) and 23.5% for homovanillic acid (HVA). However, if each patient's results were taken as a package, the sensitivities were 100% for noradrenaline, 63.6% for adrenaline, 30.3% for dopamine and 89% for HMMA. Seven recent patients had gene analysis. There were six (15.4%) deaths due directly or indirectly to the paraganglioma. Postoperative blood pressures were normal in 74%. The decrement in catecholamine values post-surgery is shown. Urinary noradrenaline values fell by a mean of 94.5% and the use of urinary noradrenaline as a tumour marker is also demonstrated.

Milestones in the evolution of phaeochromocytoma diagnosis

The history of the discovery of phaeochromocytoma and the original pathological descriptions are described. The clinical history first described in 1886 later led to the realisation that the clinical symptoms and the raised blood pressure were a consequence of catecholamine and the other hormone production by the tumour. The elucidation of its clinical associations with von Hippel Lindau disease neurofibromatosis, multiple endocrine neoplasias and Carney's triad are detailed. Pathologists and scientists are credited with establishing the current biochemical diagnoses. The developments of magnetic resonance imaging and computerised tomography have allowed accurate anatomical localisation. Gene mutations for the clinical syndromes have been identified over the last 14 years. Thus the diagnosis and treatment of this potentially lethal tumour has been made progressively easier.

Acute psychosis due to the interaction of legal compounds--ephedra alkaloids in 'vigueur fit' tablets, caffeine in 'red bull' and alcohol

A short-lasting episode of acute psychosis in a 32-year-old male which followed the consumption of alcohol, caffeine and 'vigueur fit' tablets containing ephedra alkaloids is reported. Less than two days after the event, a urine sample contained 22 microg/ml of ephedrine and 5 microg/ml of pseudoephedrine. Despite detailed pharmacological evidence being given at a jury trial, he was convicted of assault and trespass and was fined pounds sterling 16,000. An earlier incident involving misbehaviour on an aircraft again involving alcohol and ephedrine resulted in a conviction and a court order to provide twice weekly urine tests for alcohol for a period of six months. He stopped taking the alkaloid tablets after the second incident. There was no history of aberrant behaviour in this man outwith the period when taking these tablets. Ephedra alkaloids may cause psychosis and their effects can be exaggerated by interaction with caffeine and ethanol. To protect the public, the use of stimulant drugs in over-the-counter weight control programmes should be prescription only and the package insert should include a warning on the dangers of concomitant use of ethanol.

Catecholamine secretion and ploidy in phaeochromocytoma

The aim was to evaluate 24 hr urine catecholamine, HMMA and HVA excretion in relation to ploidy in phaeochromocytoma. Data from five diploid and nine tetraploid tumours showed a significant reduction in urine noradrenaline (p = 0.02) and HMMA (p = 0.03) in diploid tumours but no difference in adrenaline, dopamine and HVA excretion using the Mann-Whitney U test. None of the patients showed recurrence after a mean of 5.7 years of follow up. A review of published ploidy studies in phaeochromocytoma shows that malignancy is more than six times more common in non-diploid tumours but diploidy does not equate with benignity. No biochemical marker is a reliable index of malignancy. All patients should undergo lifetime review for recurrence.

123I-metaiodobenzylguanidine scans in phaeochromocytoma diagnosis: current clinical practice and relationship to biochemical screening

The use in practice of 123I-metaiodobenzylguanidine (MIBG) scans in phaeochromocytoma diagnosis in a teaching hospital over an eight-year period is reported. MIBG scans were performed in 43 patients and the clinical context is reviewed and reported in 42 of these. A paraganglioma and five phaeochromocytomas were found in the MIBG series. There were no false negative MIBG scans. CT was performed in 61.9%, abdominal ultrasound in 45.3% and MRI in 7.1% of the patients. Urinary catecholamines and metanephrines are considered the best screening tests for phaeochromocytoma and false positive biochemistry values were associated with MIBG scans in 35% of the cases. Despite published limitations on its sensitivity, MIBG scans were the only modality used in 21.4%; 25% of the scans were performed for clinical reasons when the biochemical screen was within the reference range. MIBG is superior to CT and MRI for the localisation of suspected recurrence after surgery and is also useful for the detection of extra adrenal tumours and metastases.