Medicine and the Law

The South African (SA) medical internship training programme model was recently revised to extend training into the primary care platform. In this article, we reflect on the experiences of training under the new model from an intern perspective. We use these reflections to make recommendations to the Health Professions Council of SA on how to further improve the training model by implementing systems that guide and empower the intern doctor practising at a primary level of care.

1250 Introduction of a New Electronic System in Surgery during the COVID-19 Pandemic

Aim

The ongoing COVID-19 pandemic has impacted all aspects of clinical practice. Preventative measures to avoid spread of the virus has included maintaining social distancing, thus making surgical handovers and ward care particularly challenging. The surgical department at PAH were able to reflect on what improvements could be made to the current system during this time, with a particular focus on efficiency and information governance, while also maintaining social distancing. Due to the advancement in information technology, electronic systems have become widely used throughout the NHS and a quality improvement project was introduced to try and improve our department using an electronic handover

Method

A quality improvement project was carried out, with questionnaires sent out pre- and post-implementation to evaluate the impact of the new electronic handover.

Results

Implementation of the electronic handover improved the safety and efficiency of the surgical department, particularly with information governance (p < 0.001), efficiency of ward rounds (p = 0.002) and social distancing. Less doctors were taking lists home (p < 0.001) and fewer doctors needed to return to the MDT room during ward rounds to check key clinical information (p < 0.001). Close to 50% of doctors said that the implementation of an electronic system reduced the need to be in crowded MDT rooms to check patient information.

Conclusions

There were clear benefits to using an electronic healthcare system both for satisfaction of workers and for patient care. The project used pre-existing IT software that was modified through collaboration with the IT department and is something that will continue to be improved in the future.

160 Informed Consent for Surgery at Resumption of Elective Activity After the First Wave of COVID-19

Aim

The Royal College of Surgeons of England published guidance on consent during COVID-19. Through this study, we aimed to assess our local consent adherence to these guidelines on the resumption of elective activity after the first wave of COVID-19.

Method

This prospective review of consecutive elective surgical consent forms was conducted from 20 July 2020 to 16 August 2020 at the Princess Alexandra Hospital NHS Trust, England. The primary outcome was evidence of COVID-19 risk documentation on the consent forms.

Results

A total of 116 patients’ consent forms were reviewed. Most patients were American Society of Anaesthesiologists (ASA) grade 2 (n = 70; 60.34%). Only 25 consent forms (21.55%) had COVID -19 and its associated risks documented, with registrars being the most compliant (19/46; 41.3%) followed by consultants (6/51; 11.7%). With regards to the surgical sub-specialities, general surgery, orthopaedics and ENT had the highest compliance with the guidance.

Conclusions

As the elective activity resumes, peri-operative risks of COVID-19 should be weighted in during the informed consent process, as mentioned in the latest international guidelines on consent to avoid litigation and negligence claims.

Consumer liking of M. longissimus lumborum from New Zealand pasture-finished lamb is influenced by intramuscular fat

Palatability of meat is known to be affected by intramuscular fat (IMF), but the effect in relatively low-fat New Zealand lamb is unknown. This study evaluated the eating quality of 108 loins (M. longissimus lumborum) from a single flock of ewe-lambs. Loins ranged from 1.09-5.68% IMF and were stratified into 6 groups: 1.65, 2.12, 2.65, 3.20, 3.58 and 4.40%. Consumers' (n = 165) overall liking of lamb increased significantly at around 3% IMF, achieving maximum scores at 4% IMF. One consumer cluster (n = 111) showed a linear increase in overall liking with increasing IMF%, regarded as 'IMF lovers: the more the better', while a second cluster (n = 54) preferred 2.5-3.5% IMF, described as 'IMF optimizers: just the right amount'. IMF% was modestly correlated (~ + 0.25) with all sensory attributes except juiciness. Liking scores were modestly correlated with monounsaturated (~ + 0.25) and polyunsaturated (~ - 0.20) fatty acids. Results suggest aiming for IMF% levels in New Zealand lamb beyond 3% to maximize eating quality for premium markets in particular.

Relationship Between Smoking Status and Serum Lipids in a Hyperlipidemic Population and Analysis of Possible Confounding Factors

The aim of our study was to estimate the potential relationship between smoking behavior and other coronary heart disease risk factors in 250 hyperlipidemic patients. We present data obtained through self-reporting of the number of cigarettes smoked per day, measurements of three tobacco markers, and data on dietary habits and lipid variables. We measured cotinine (by HPLC) and thiocyanate and used a recent colorimetric assay for the indirect evaluation of the nicotine metabolites in a single urine specimen. Mean values of nicotine metabolites, expressed as cotinine equivalents, were 6.7, 39.9, and 79.4 mumol/L, respectively, for nonsmokers, light smokers (7.7 cigarettes per day), and heavy smokers (25.8 cigarettes per day). We found that light smokers have higher concentrations of cotinine and nicotine metabolites in proportion to the number of cigarettes smoked per day than do heavy smokers. Thus, the simple colorimetric assay can accurately evaluate smoking status. Hyperlipidemia and smoking are linked by an intricate network of multiple relations. The concentration of high-density lipoprotein (HDL) cholesterol is lower in heavy smokers, and the concentrations of triglycerides and cholesterol are higher. The 0.11 mmol/L difference in HDL cholesterol between light and heavy smokers is close to the results of previous papers; however, when gender, dietary habits (including alcohol intake), and data on body mass index are included in a multiple regression analysis, there is no longer an association between HDL cholesterol concentrations and smoking status. Therefore, these different dietary habits may be confounding factors that partly explain the pattern of lipid variables.

Effects of prolonged-release melatonin, zolpidem, and their combination on psychomotor functions, memory recall, and driving skills in healthy middle aged and elderly volunteers

BACKGROUND

Melatonin is an important regulator of the sleep-wake cycle. A prolonged-release formulation of melatonin (PR-M) that essentially mimics the profile of the endogenous production of the hormone is effective in the treatment of insomnia in patients aged 55 years and older. Because hypnotics result in impairments of various cognitive skills, it is important to examine the cognitive effects associated with the use of PR-M.

OBJECTIVES AND METHODS

The effects of therapeutic oral doses of PR-M (2 mg), zolpidem (10 mg) and their combination administered at bedtime on cognitive functions in healthy subjects aged 55 years and older (12 males + 4 females, age 59.4 +/- 3.2 years) were assessed in a randomized, double-blind, placebo-controlled, and four-way crossover study. Psychomotor functions, memory recall, and driving skills were assessed at 1 and 4 h following administration and the next morning.

RESULTS

Compared to placebo, PR-M alone did not impaired performances on any cognitive tasks. Zolpidem significantly impaired psychomotor and driving performance 1 h and 4 h post-dosing, and early memory recall; these impairment were exacerbated with PR-M co-administration. No effects on next morning psychomotor or driving performance were observed except that the decline in memory recall after zolpidem was more pronounced in the next day. No pharmacokinetic interactions were found.

CONCLUSIONS

This study extends previous researches showing impairment of cognitive functions by zolpidem within 5 h post-administration. Further, PR-M use was not found associated with impairment of psychomotor functions, memory recall, and driving skills, and point to a pharmacodynamic interaction between melatonin and GABA-A modulators.

SpO2 sensor embedded in a finger ring: design and implementation

A novel concept of Oxygen Saturation (SpO2) sensor embedded in a finger ring is presented in this paper. Due to the mechanical conception of the probe, the sensor fits any finger topology and assures a constant force applied to the phalanx. Ambient light artifacts are rejected at the analog electronics level. Finally, an innovative distribution of light sources and detectors and a dedicated signal processing procedure resolve the anatomical heterogeneity of different phalanx topologies, compensate low perfusion indexes due to the phalanx anatomy and estimates equivalent pulse oximetry SpO2 indexes. First in-vivo validation results of the novel sensor are discussed at the end of the paper.

SENSATION remote monitoring system for enabling the "anytime, anywhere" monitoring of patients with selected sleep disorders

The SENSATION Integrated Project aims at promoting the health, safety and quality of life of people and protect the environment by reducing relevant accidents and thus the impact on environment through the application of novel micro and nano sensors and related technologies, of low-cost and high-efficiency, for physiological state monitoring. The focus of the work will be the brain activity, including the sleep and wakefulness states and their boundaries, stress, inattention and hypovigilance states, for hypovigilance detection, prediction and management as well as diagnosis, treatment and remote monitoring of sleep disorders. In this paper, a presentation of the application scenarios of the integrated medical system will be made.

[Measurement of urinary free cotinine. Comparison with the level of expired air carbon monoxide]

BACKGROUND AND AIM

Cotinine is a very reliable index for the estimation of active or passive smoking. Sampling from a single urine void is well accepted by smokers who are willing to stop. It is not possible to exclude modification of urine cotinine according to beverage intake. The aim of this study was to determine if urine cotinine concentration must necessarily be adjusted to creatinine or not, by making comparison with expired air carbon monoxide.

MATERIAL AND METHODS

Carbon monoxide was measured in 53 smokers coming for the first time in a smoking cessation program. Urine cotinine was measured by HPLC-UV. The cut-off value for abstinence is 8ppm and 0.05 mg/L, repectively. Urine creatinine was determined using the Jaffe reaction.

RESULTS

Mean CO level was 18.5 +/- 10.6 ppm and mean urine cotine was 1.45 +/- 0.86 mg/L. Eight smokers had CO 8 ppm. They should be considered as abstinent. However, only one of them had a cotinine under the detection limit. Urine creatinine varied in a large range (0.7 - 35 mmol/L). But, cotinine was only weakly correlated to creatinine (r = 0.279, p = 0.037). There was a highly significant correlation between cotinine and CO (0.649, p = 0.0001). The correlation of cotinine/creatinine versus CO was not significant (r = 0.249, p = 0.072). In order to take into account fluid intake, urine cotinine of each sample was adjusted as if creatinine was equal to the mean (8.3 mmol/L) of the group of subjects. The correlation observed with adjusted or non adjusted cotinine and CO (r = 0.640, p < 0.0001) was the same.

CONCLUSION

Urine cotinine from a single void is an accurate index of tobacco smoking at the individual level. There is no need to adjust cotinine concentration, taking into account urine creatinine. Measurement of urine cotinine can be useful to manage smokers who deliberately wish to overcome tobacco dependence, offering the opportunity to provide an adequate level of nicotine substitutive therapy. It is also of peculiar importance to follow-up pregnant women and smokers for whom cessation is required after a clinical event. Finally, absence of cotinine in urine can be used to document abstinence from tobacco products.

[Urinary cotinine and nicotine metabolites measurement]

According to the recent regulations (Circulaire DGS/DH du 3 avril 2000), tobacco dependence must be determined by the measurement of urine nicotine metabolites. Various assay methods are presently available. They were tested in order to evaluate their analytical performances and to determine how they can be used for the clinical management of smoking cessation.

MATERIAL AND METHODS

Urine samples from a single void (n = 97) were obtained from active and abstinent smokers (with or without nicotine substitutive therapy). They were all analyzed by the various methods. Cotinine concentration was measured in six laboratories, using HPLC combined with UV detection according to a standardized procedure (Ann Biol Clin 2002 : 60 : 263-72). Immunoassay methods were also tested and the values obtained from urine samples were compared to urine cotinine measured by HPLC-UV.

RESULTS

HPLC-UV: Urinary cotinine varied in a range from undetectable to 4 mg/L. An interlaboratory comparison was performed according to the Valtec procedure (calculation of equation of Deming, chart of differences). There was a good accordance between laboratories. Cotinine concentration was only slightly influenced by fluid intake, as shown by a poorly significant correlation between cotinine and creatinine (r = 0.23, p = 0.05). Homogeneous immunoassays: The two homogeneous immunoassays (Cotinine) from Thermo Electron and Cotinine Enzyme Immunoassay commercialized by Microgenics were highly correlated (r = 0.97). The correlation was not so strong with HPLC-UV (r = 0.86). Firstly, values were found higher with immunoassays because antibodies crossreact with 3-hydroxycotinine. Secondly, the ratio of immunoassays values to HPLC-UV values varied according to urine specimens. Finally, there was a highly significant correlation with urine creatinine (r = 0.40, p = 0.0001), thus indicating the influence of fluid intake. Heterogeneous immunoassay: The kit Metabolites of Nicotine commercialized by DPC France was tested on the analyzer Immulite, using a procedure specifically established for urine. Antibodies revealed a large spectrum of nicotine metabolites. Therefore, the values were much higher than those observed for the same urine samples with homogeneous immunoassays.

CONCLUSION

HPLC-UV can be recommended for the measurement of urinary cotinine, as it was shown a good accordance between laboratories. The low detection limit is of interest for the diagnosis of Environmental Tobacco Smoking. Homogeneous immunoassays can be easily used for routine analysis as they can be performed directly on urine specimen. The results must be interpreted according to cut-off values specifically established according to homogeneous or heterogeneous immunoassays. Variability induced by fluid intake must be taken into account. The interest of the heterogeneous immunoassay needs to be confirmed for the diagnosis of Environmental Tobacco Smoking.

[Antiviral sensitivity of herpes simplex virus in immunocompromised patients]

The Herpes simplex Virus (HSV) resistance to acyclovir (ACV) occurs in a 5% of the inmunocompromised patients, approximately. The treatment with analogs of nucleosides, causes the appearance of resistent HSV-ACV stocks (ACVr) which can be produced by alteration in genes coding for the TK or the DNA-polymerase. A previous large-scale clinical study on ACVr HSV strains isolated from patients infected with human immunodeficiency virus indicated that 96% of ACVr HSV mutants were low producers of, or deficient in, TK activity (TK-), with 4% being TK mutants with an altered substrate specificity. No DNA Pol mutants were isolated. The pirophosphate analogs generate resistance in the gene of DNA-polymerase by mutation. In this paper we show the methodology used for the determination of sensibilite profiles to ACV and Phoscarnet (PFA) in a population of inmunocompromised patients. We analized 46 HSV strain from vesicular injuries of transplanted patients. All samples, were inoculated in human fibroblasts and the HSV isolates were identified by inmunofluorescence whith monoclonal antibodies. These strains were amplified and the profile of susceptibility determinated in Vero cells, using 100 tissue culture inhibition dosis 50 (TCID50) of each Viral stock and the specific antiviral drugs in different concentrations. The cytopathic effect (CPE) was evaluated after 72hs. post infection. The 50% inhibitory concentration (CI50) was calculated from the percentage of inhibition of the ECP based on the concentration of the drug. From 46 isolations, 26 were HSV-1 and 20 were HSV-2. Two of them, one HSV-1 and one HSV-2, were resistant to ACV and none of the isolates were resistant to PFA.

[What perception have smokers of nicotine and tar yields of cigarettes?]

INTRODUCTION

Advertising information on cigarette package participate to the reduction of health risks from smoking. Impact on smokers has been poorly studied. This study intended to determine the smoker perception of nicotine and tar yields of cigarettes.

METHODS

Consulting in an outpatient smoking cessation clinic, 171 smokers answered freely and spontaneously to a questionnaire evaluating their perception of nicotine and tar yields, cigarette consumption (number and brand), nicotine dependence. Simultaneously, biological tobacco markers were measured.

RESULTS

The number of cigarettes, nicotine dependence and specific tobacco markers were not significantly different according to the cigarette type: "full savour", "light" or "ultra light". Women smoked less than men and 54% preferred "light" cigarettes versus 37% of men. These smokers were entering a tobacco cessation program, it was assumed they had lead a prior reflection about their smoking habits. Only 8% of them gave the correct values of nicotine and tar yields and 14% gave approximate values. Tar levels were highly underestimated.

CONCLUSIONS

This study shows that smokers have actually no interest for nicotine and tar yields. As the new decree which modifies manufacture's obligation concerning the legal mentions, is applicable in January 2004 in France; our conclusion may change in the future.

[Prescription of bone remodeling markers in hospitals]

Biochemical markers of bone turnover have for several years been considered as valuable parameters in research clinical studies, but their use in individual patients is still debated. Recently several position papers have proposed guidelines for their use in clinical practice in patients with post menopausal osteoporosis. In the present article, we report the results of a survey which aims at comparing the actual modalities of prescription of French physicians with the above-mentioned recommendations. We contacted by phone clinical chemists from 158 different hospitals and asked them to transmit to the concerned physicians of their hospital a detailed questionnaire for assessing which bone marker(s) is (are) prescribed and for which purpose (s), and if not prescribed, the reason of non prescription. We were able to analyze 309 questionnaires from 89 hospitals including 5 specialties, rheumatology (35.9%), endocrinology (18.1%), gynecology (11.0%), internal medicine (22.0%) and geriatry (12.9%). The results showed large discrepancies between the mode of prescription of a subset of physicians and the guidelines. The most often evoked reason for non prescription was a lack of information about bone markers suggesting a need for teaching courses. This survey has also shown that many physicians do not know exactly which parameters are effectively measured in their hospital and which are addressed to specialized laboratories underlining the importance of the dialogue between clinicians and clinical chemists. We propose that in a given hospital, the present article may serve as a basis for a discussion between clinicians and biologists about the development and/or the optimization of the measurements of these markers of bone turnover.

[Biomarkers of tobacco smoke exposure]

Tobacco smoking is a major risk factor for cancer, cardiovascular diseases and respiratory illnesses. Smoking is increasing among children and adolescents with subsequent consequences on the health. Furthermore, maternal tobacco smoking during pregnancy adversely affects prenatal growth. Nicotine, the most important tobacco alkaloid, is responsible for maintaining tobacco addiction. According to a recent Circulaire de la direction générale de la santé, nicotine dependence should be determined through questionnaires and quantitative estimate of nicotine metabolites. Nicotine blood level fluctuates and urinary nicotine excretion is of short duration. Nicotine is intensively metabolized in the liver and oxidized into cotinine. Urinary measurement of cotinine appears to be highly related with the degree of intoxication and to allow the differentiation between non exposed and exposed non-smokers. In order to check the present application of nicotine metabolites measurement, a survey was conducted in 340 smoking cessation units. Forty percent physicians (n = 137) answered the survey. For 17% of them, the quantification of nicotine metabolites is included in their daily practise and for 79%, guidelines about cotinine measurement should be given in France. Sixty-seven biologists answered the survey. Recommendations for immunoassay and HPLC determination of cotinine should be given as reported by 66 and 44% of them respectively. Indeed, urinary cotinine measurement with high performance liquid chromatography is highly sensitive and specific. However, immunoassays are more convenient. These two approaches are presently under investigation in order to provide guidelines for optimal use in various clinical situations. Traditional measures for nicotine dependence are the number of cigarettes smoked per day, nicotine intake expressed as mg per day, Fagerstr m questionnaire, expired air carbon monoxide, thiocyanates and cotinine levels in biological fluids. Urinary cotinine measurement is the most useful for the follow-up of smoking cessation including adjustment of nicotine replacement therapy, especially after a clinical event or for the follow-up of smoking pregnant women. It allows the detection of passive smoke exposure in children who are hospitalized for recurrent respiratory illnesses.

Association with the Syndrome "Basses Richesses" of Sugar Beet of a Phytoplasma and a Bacterium-Like Organism Transmitted by a Pentastiridius sp

ABSTRACT The syndrome "basses richesses" of sugar beet (SBR) was first observed in 1991 in Burgundy, France. A cixiid planthopper, Pentastiridius beieri, has been proved to be involved in the transmission to sugar beet of a stolbur phytoplasma, which could be detected in some affected plants. In 2000, periwinkle and sugar beet exposed to field-collected cixiids developed symptoms similar to SBR on sugar beet. Use of 4'-6-diamidino-2-phenylindole (DAPI) staining and transmission electron microscopy confirmed the presence of phytoplasma in some of the plants, which were also positive for this pathogen in a polymerase chain reaction (PCR) analysis. A phloem-restricted gram-negative bacteria was seen in all other plants with symptoms but PCR-negative for phytoplasma. Three primer pairs reported as diagnostic for phloem-limited bacteria were tested but only primers specific for 'Candidatus Phlomobacter fragariae' gave a positive signal, which related to the presence of DAPI-stained bacteria-like objects in diseased plants. Although phytoplasma and bacterium-like organisms were associated with the same macroscopic symptoms on sugar beet, histochemical analysis of phloem cells showed that phytoplasma were associated with cell necrosis and cell wall lignification, while bacteria were associated with these same abnormalities as well as deposit of phenolic compounds in the lumen of phloem cells.

[Scleredema adultorum in secondary hyperparathyroidism]

Scleredema adultorum, or Buschke's scleredema, belongs to the group of mucinoses. It is characterised by thickened and indurated skin. Histopathology shows thickened dermis with an infiltration of mucin between swollen collagen bundles. There are reports about many associations with scleredema adultorum, e.g., with diabetes mellitus and multiple myeloma. One case is known with associated primary hyperparathyroidism. For the first time we report a case of scleredema adultorum and secondary hyperparathyroidism, in a 46-year-old patient. Both forms of hyperparathyroidism have increased levels of parathormone. Therefore, these increased levels could have an influence on collagen metabolism.

[Biochemical diagnosis of pheochromocytoma and neuroblastomas]

Pheochromocytoma and neuroblastoma are distinct tumours, but their biological diagnosis is based on secretion increase of one or several catecholamines. Assays have to be very sensible and specific for an early diagnosis. 24 hours urinary catecholamines and metabolites are currently measured, but technical improvements permit plasma metanephrine assay, an excellent indicator of pheochromocytoma. HPLC coupled to electrochemical detection represents the most efficient methodology. After a review of urinary and plasma assay methods, the authors show usual values of catecholamines, metanephrines, HVA and VMA, according to ages, and give examples of results encountered in classical or not tumours and in falsely positive cases. Urinary metanephrine assay is the most sensible and specific in biological diagnosis of pheochromocytoma, while catecholamines and VMA assays lack of sensibility. Results have to be given by 24 hours and by creatinine ratio. Metanephrine assay can be performed also in plasma and exhibits the same interest. However, in urine as in plasma, in case of renal failure, results cannot be interpreted. Neuroblastoma biological diagnosis is based classically on HVA, VMA, and dopamine assays, nowadays only in 24 hours urine (or in urinary micturition for screening), and results are also expressed as creatinine ratio. But even if several assays are advisable, 5% of the neuroblastoma cases do not produce increased catecholamine values. In some cases, metanephrine assay could be of interest. After the age of 12 months, clinical expression of neuroblastoma is dramatic in 70% of cases. So, a biological screening has been experimented in several countries including France. A French translation of the consensus conference report (1998) is appended, which shows the complexity of neuroblastoma screening. Now, there is no evidence that early tumour detection by screening lessens the mortality rate, but a weak benefit is not excluded.

[Hepatotoxicity of a synthetic cortisol antagonist: OP'DDD (mitotane)]

The adrenolytic agent, Op'DDD (Mitotane) has been employed for almost 50 years for treatment of Cushing's syndrome. Despite clinical observations of elevation of hepatic enzymes encountered in patients taking the drug, there are few published data regarding the frequency, time course and factors that might influence hepatic toxicity of Mitotane. We analysed 10 patients consecutively treated with Mitotane for Cushing's syndrome. We measured hepatic transaminase and gamma glutamyl transferase before, during and after treatment. The study population included 6 women and 4 males, with a mean age of 41 years. Seven patients presented Cushing's disease while two had adrenal tumours and one had an undetermined origin of Cushing's syndrome. After a progressive increase, patients were being treated with a mean dosage of 9 g per day. All patients had elevation of either GGT or ALAT and all but one had elevation of transaminase (the maximum increase was sixfold the basal value). The only variable correlated with hepatic increase was the body mass index. In contrast, the severity of the disease, alcohol intake, and other biological characteristics were not correlated with transaminase elevations. We conclude that transaminase increase is encountered in the vast majority of patients treated with Mitotane. Levels at which the drug should be withdrawn remain to be established.

Intergeniculate leaflets lesion delays but does not prevent the integration of photoperiodic change by the suprachiasmatic nuclei

The duration of the photosensitive phase of the suprachiasmatic nuclei (SCN), as revealed by light-induced Fos protein expression, depends on the photoperiod and is tied to the length of the night. We show here in Syrian hamsters that after a transfer from long to short photoperiod, lengthening of the photosensitive phase of the SCN is significantly delayed but not abolished when the intergeniculate leaflets (IGL) are lesioned. Thus IGL modulate the integration by the SCN of a photoperiodic change.

Mycoses in the transplanted patient

The incidence of invasive fungal infection (IFI) has increased considerably over the past 20 years, and transplant recipients are at especially high risk for fungal infections owing to their overall immunosuppressed condition. Organ transplantation procedures were incorporated as a therapeutic option for many patients who lacked the normal functions of organs such as the heart, liver, kidney, lung, pancreas and small bowel. The prevalence of IFI in solid organ transplant (SOTR) patients ranges from 5 to 50% in kidney and liver transplants, respectively. In bone marrow transplant (BMT) patients, IFI are major causes of morbidity and mortality due to the protracted neutropenic period and graft-versus-host disease. Candida spp. and Aspergillus spp. account for >80% of fungal episodes in both SOTR and BMT. The development of new immunosuppressive agents, new prophylaxis strategies (as pre-emptive therapy) and the improvement in surgical techniques led to increase survival of transplant recipients. In this session, a clear and concise update of the recent advances in the laboratory diagnosis of candidiasis and aspergillosis in this kind of patients was presented. However, we still need to establish more rapid, sensitive and specific methods for IFI diagnosis. Representatives of the 'Subcomision de Infecciones en el Paciente Neutropenico y Transplantado (SIPNYT)' de la Sociedad Argentina de Infectologia (SADI), presented the results of an unusual multicenter study both retrospective and descriptive studies of IFI in SOTR and BMT patients in Argentina. In addition, a study of IFI in 1,861 SOTR patients from four centers and the analysis of IFI in 2,066 BMT patients from all 12 BMT centers from Argentina was presented. From these studies it can be concluded that 'all transplant recipients are not the same' and that they should be stratified according to their different risk degrees in order to determine the best prophylaxis and treatment strategies.

[New non-lipidic biological markers of atherosclerosis]

Recent research indicates that both inflammation and infection of coronary arteries are intimately involved in the development and the progression of atherosclerosis. Pathophysiological mechanisms of formation of the atheromatous plaque are complex, resulting from the activation of endothelial cells, monocytes and foam cells, and smooth muscle cells. Numerous molecules are involved in these mechanisms, including adhesion molecules, pro-inflammatory and anti-inflammatory cytokines, chemokines, extracellular matrix remodelling enzymes, coagulation and fibrinolysis factors and infectious agents. Studies have suggested a potential role for these molecules as markers of the development of coronary artery disease and of adverse cardiac-related outcomes in patients with known coronary artery syndromes, in combination with independent risk factors such as homocysteine. This review presents recent data that could contribute to use of these markers for the diagnosis and the evolution of atherosclerosis. in clinical practice.

Homocysteine and lipid lowering agents. A comparison between atorvastatin and fenofibrate in patients with mixed hyperlipidemia

BACKGROUND

Hyperhomocysteinemia is a risk factor for cardiovascular disease. Elevation in homocysteine levels has recently been demonstrated during lipid lowering treatment with fibrates. We compared the effect of a statin and a fibrate (atorvastatin and fenofibrate) on plasma levels of homocysteine and other thiol compounds in hyperlipidemic patients.

METHOD AND RESULTS

The study was of open randomized, parallel design with a preliminary screening phase, and a 6 week placebo period. After the placebo period, patients were allocated randomly to atorvastatin or fenofibrate for a 6 month period. Plasma thiols were assayed by high pressure liquid chromatography with fluorescence detection. There were 29 patients in the fenofibrate group and 24 in the atorvastatin group. Fenofibrate induced a significant increase in both homocysteine and cysteine plasma levels (+35.8 and +18%, respectively, P<0.0001); by contrast, cysteinylglycine remained stable. There were no significant changes in any thiol compounds in the atorvastatin group. Both treatments induced a significant decrease in uric acid, although fenofibrate was noticeably more effective than atorvastatin (-22.8 and -6.4%, respectively). Fenofibrate induced a non-significant increase in creatinine (12%) while atorvastatin reduced it (4.7%, NS).

CONCLUSION

Our study confirms that the induction of elevations in plasma homocysteine and cysteine levels are a distinct feature of the pleiotropic effects of fibrates. Further studies are needed not only to investigate the potential deleterious effects of this modification, but also to define the specific mechanism which underlies such fibrate-mediated action.

[Biochemical markers of bone remodeling: pre-analytical variations and guidelines for their use. SFBC (Société Française de Biologie Clinique) Work Group. Biochemical markers of bone remodeling]

Biochemical markers of bone turnover have been developed over the past 20 years that are more specific for bone tissue than conventional ones such as total alkaline phosphatase and urinary hydroxyproline. They have been widely used in clinical research and in clinical trials of new therapies as secondary end points of treatment efficacy. Most of the interest has been devoted to their use in postmenopausal osteoporosis, a condition characterized by subtle modifications of bone metabolism that cannot be detected readily by conventional markers of bone turnover. Although several recent studies have suggested that biochemical markers may be used for the management of the individual patient in routine clinical practice, this has not been clearly defined and is a matter of debate. Because of the crucial importance to clarify this issue, the Société Francaise de Biologie Clinique prompted an expert committee to summarize the available data and to make recommendations. The following paper includes a review on the biochemical and analytical aspects of the markers of bone formation and resorption and on the sources of variability such as sex, age, menstrual cycle, pregnancy and lactation, physical activity, seasonal variation and effects of diseases and treatments. We will also describe the effects of pre-analytical factors on the measurements of the different markers. Finally based on that review, we will make practical recommendations for the use of these markers in order to minimize the variability of the measurements and improve the clinical interpretation of the data.

[Hyperhomocysteinemia and arterial or venous thrombosis. Retrospective study of 75 cases]

OBJECTIVE

Previous studies suggest that hyperhomocysteinemia may be a risk factor for arterial and venous thrombosis. We retrospectively analyzed data from 75 patients with thrombosis.

PATIENTS AND METHODS

Thirty-four patients had arterial thrombosis, 22 venous thrombosis and 19 venous and arterial thrombosis. Of the 75 patients (49 men and 26 women, mean age 49 +/- 15 years) about two-thirds had recurrent episodes of thrombosis.

RESULTS

Hyperhomocysteinemia was defined as serum homocysteine level above 14.1 mumol/l (mean + 2.7 SD in healthy subjects) and was found in 67 patients (89%, CI95% = 80-95). Mean total homocysteine concentration was 21.6 +/- 13.6 mumol/l for the 75 patients. About half of the patients were smokers, 35% had hypertension and 25% high serum cholesterol. There was no significant relationship between serum homocysteine level and smoking status, hypertension or serum cholesterol level. Ten patients (13%, CI95% = 7-23) had low serum cobalamin (< 150 pmol/l). Serum folates were < or = 10 nmol in 41% of the patients in the arterial thrombosis group (CI95% = 25-59), in 27% in the venous thrombosis group (CI95% = 11-50), and in 31% in the arterial and venous thrombosis group (CI95% = 13-57). Thirteen patients received vitamin B supplementation. Hyperhomocysteinemia decreased in 12/13 patients (CI95% = 64-100) and returned to normal values in 9/13 patients (69%, CI95% = 38-91).

CONCLUSION

Our data show that hyperhomocysteinemia is frequently found in arterial and venous thrombosis. Further studies are needed to determine the clinical impact of homocysteine lowering therapy.

Kinetics of serum tumor marker concentrations and usefulness in clinical monitoring

Only a few markers have been instrumental in the diagnosis of cancer. In contrast, tumor markers play a critical role in the monitoring of patients. The patient's clinical status and response to treatment can be evaluated rapidly using the tumor marker half-life (t(1/2)) and the tumor marker doubling time (DT). This report reviews the interest of determining these kinetic parameters for prostate-specific antigen, human chorionic gonadotropin, alpha-fetoprotein, carcinoembryonic antigen, cancer antigen (CA) 125, and CA 15-3. A rise in tumor markers (DT) is a yardstick with which benign diseases can be distinguished from metastatic disease, and the DT can be used to assess the efficacy of treatments. A decline in the tumor marker concentration (t(1/2)) is a predictor of possible residual disease if the timing of blood sampling is soon after therapy. The discrepancies in results obtained by different groups may be attributable to the multiplicity of immunoassays, the intrinsic characteristics of each marker (e.g., antigen specificity, molecular heterogeneity, and associated forms), individual factors (e.g., nonspecific increases and renal and hepatic diseases) and methods used to calculate kinetics (e.g., exponential models and timing of blood sampling). This kinetic approach could be of interest to optimize patient management.

Cysteine is a cardiovascular risk factor in hyperlipidemic patients

Several studies have reported that moderate hyperhomocysteinemia is related to an increased risk for atherosclerosis, but few data are available with regard to any other thiol compound having a potential vascular toxicity. Therefore, we measured both total cysteine and homocysteine plasma levels in patients with hyperlipidemia (242 males and 147 females, 41-65 years old). Homocysteine was higher in males than in females, 13.2+/-4.1 versus 11.1+/-3.4 micromol/l (P<0.0001). The mean cysteine level was 243.3+/-45.7 micromol/l in the whole study population. The subjects were split in two groups, symptomatic patients with cardiovascular disease (n = 106) and asymptomatic subjects (n = 283). Blood pressure, smoking status, total cholesterol, LDL-cholesterol and triglycerides did not statistically differ between groups, but the mean HDL-cholesterol level was lower in symptomatic patients (1.24+/-0.38 versus 1.42+/-0.41, P<0.0001). Cysteine levels were higher in patients with cardiovascular disease than in asymptomatic patients, respectively 254.7+/-47.7 versus 239.1+/-44.3 micromol/l (P = 0.003). A similar result was found for homocysteine, respectively 13.1+/-4.3 versus 12.2+/-3.9 micromol/l (P = 0.05). To analyse whether cysteine levels were related to atherosclerosis independently of age, adjusted levels were compared between asymptomatic patients with normal carotid arteries (n = 176), carotid atherosclerosis (n = 107) and symptomatic patients (n = 106). Age adjusted cysteine levels differed significantly between groups (P = 0.027) while the P-value was of borderline significance for homocysteine (P = 0.09). Odds ratios for having symptomatic cardiovascular disease were 1.81 (95% CI, 1.02-3.21) and 2.05 (95% CI, 1.16-3.60) for the mid and highest tertiles of cysteine using the lowest as the reference. After adjustment in a multivariate model including age, sex, and creatinine, the odds ratio for disease remained significant between the highest tertile versus the lowest (OR = 1.89). Adjusted odds ratios were found to be weaker when homocysteine tertiles were compared. Our data suggest that plasma total cysteine is a risk factor for atherosclerosis in hyperlipidemic patients.

Chagas' disease in patients with kidney transplants: 7 years of experience 1989-1996

Chagas' disease was present in 17.22% of persons undergoing kidney transplantation in an Argentine Hospital. The criterion for attributing reactivation of chronic Chagas' disease and transmission of Trypanosoma cruzi to grafts was detection of parasites in blood (patent parasitemia) or tissues. Reactivation was diagnosed in 5 (21.7%) of 23 recipients. Ten (43.4%) of 23 chagasic recipients without reactivation of chronic Chagas' disease had abrogation of serological reactivity. T. cruzi infection was transmitted to 3 (18.7%) of 16 non-chagasic recipients. Reactivation and infection were diagnosed by patent parasitemia or cutaneous panniculitis. For diagnosis, detection of parasites in blood and tissues had more relevance than serology. Sequential monitoring detected early reactivation and infection, permitting application of preemptive or therapeutic therapy with benznidazole, thus inhibiting, in all patients, severe clinical disease produced by a progressive and systemic replication of the parasite.