[ETHICAL ASPECTS OF INFORMED CONSENT IN REFRACTIVE SURGERY]. / ASPECTS ÉTHIQUES DU CONSENTEMENT ECLAIRÉ EN CHIRURGIE RÉFRACTIVE.

With the introduction of the use of Laser assisted surgery, refractive eye surgery knows a very large success. Surgery of well being, it requires that an extensive information is delivered to the patient concerning the benefit and possible side-effects of the available treatments. This information process may reduce the frequency of negligence claims relating to Laser eye surgery.

[End of life care in the elderly]. / Gérer la fin de vie chez le sujet âgé.

The increase in life expectancy is associated with a good quality of life until a very old age. However, the unavoidable aging process eventually affects the autonomy of the patient and may force the individual to live in a nursing home. The alteration of sensorial functions and the increased number of degenerative diseases may finally induce a physical and psychological burden that might lead to resort to palliative care, end of life sedation, and in some cases, euthanasia.

[The medical decision for the non-competent patient]. / La décision médicale chez le patient incompétent: aspects légaux et ethiques.

The evolution of the therapeutic relation from a paternalistic to a collaborative one has increased the legal and ethical problems related to the medical care in non competent patients. The recent Belgian law on the rights of the patient (August 22, 2002 ) and the advice of the Belgian Council of the Medical Association on this matter provide the practitioner with clear directives. However, the responsibility of the final decision always remains in the hands of the medical doctor as the protector of the patient.

[Anterior lenticonus: diagnostic aid in Alport syndrome]. / Le lenticône antérieur: aide diagnostique au syndrome d'Alport.

Anterior lenticonus is a rare condition in which the lens presents a conical protrusion of its anterior cortex. Sometimes isolated, it may be an ocular manifestation of Alport syndrome, a hereditary nephritis accompanied by deafness and other ocular signs such as flecked retinopathy or posterior polymorphous corneal dystrophy. All these manifestations are a result of a genetic defect in type IV collagen, a major component of basal membranes in the human body. The clinical aspects and therapy of anterior lenticonus and Alport syndrome are described, as well as the exploration that must begin when anterior lenticonus is discovered. This exploration is essential so that this diagnosis can be made as soon as possible.

Effect of hemodiafiltration on pulmonary hemodynamics in endotoxic shock.

Hemofiltration can improve pulmonary hemodynamics during septic shock. The main objective of the study was to determine whether hemodiafiltration (HDF) would also have beneficial effects on pulmonary hemodynamics during septic shock. In the Endo group, six anesthetized pigs received a 0.5 mg/kg endotoxin infusion over 30 min. In the HDF group (n = 6), HDF was started 30 min after the end of the endotoxin infusion, while in the Control group (n = 4) they received HDF but no endotoxin infusion. Pulmonary hemodynamics were analyzed in detail with a four-element windkessel model. Although in the Control group, HDF did not alter pulmonary hemodynamic parameters, in the HDF group, it was responsible for an amplification of the deleterious pulmonary vascular response to endotoxin insult. Our results show that HDF must be used cautiously in septic shock since it can precipitate right heart failure by increasing pulmonary vascular resistance.

[Prevention of chronic renal failure in the adult]. / Prévention de l'insuffisance rénale chronique chez l'adulte.

Chronic renal failure is an unrecognised disease, with an insidious and rather silent development, for which the general practitioners are too often passive. This review would like to insist on the detection of people at risk or with early abnormalities, on the optimal guidelines to slowdown the evolution to more severe and irreversible stages, on the prevention of uremic and cardiovascular complications and on the preparation to end stage renal treatments.

[Prevention of diabetic nephropathy: from microalbuminuria to end-stage renal insufficiency]. / Prévention de la néphropathie diabétique: de la microalbuminurie à l'insuffisance rénale terminale.

Diabetic nephropathy is one of the leading causes of end-stage renal failure in western countries. This disease develops over several years. Early stages, if they are detected in time, can lead to preventive treatment at a moment when the disease is still reversible. This paper reviews the main primary and secondary preventive measures that have been proven efficacious. Those are essentially the optimal treatment of hyperglycaemia and hypertension, and probably the use of agents that specifically block the renin-angiotensin axis. We briefly discuss the results of the main studies that have led to those conclusions.

[Evaluation of glomerular filtration rate in clinical practice]. / La mesure du débit de filtration glomérulaire en clinique quotidienne.

Glomerular filtration rate (GFR) is the most frequently used parameter to evaluate the renal function. GFR may be estimated with serum creatinine, creatinine clearance based on 24 hours urine collection or Cockcroft formula. All these methods have bias. Other approaches have thus been proposed. The limitations and advantages of isotopic methods and recent mathematical approaches (MDRD formula) are reviewed.

[Cystatin C in the evaluation of renal function]. / L'intérêt de la cystatine C dans l'évaluation de la fonction rénale.

Glomerular filtration rate (GFR) is the best indicator of renal function. GFR is usually estimated by serum creatinine or the creatinine clearance calculated on urine collected over 24 hours or with the Cockcroft formula. These methods are however limited. Serum creatinine has a very poor sensitivity and urine collection is difficult. Cystatin C is a protease inhibitor produced in a constant manner by nucleated cells. This molecule is freely filtrated by the glomerule and quite completely catabolized in the proximal tubules. Its plasmatic concentration might thus be used to estimate GFR. Presently available data allow to conclude that plasmatic cystatin C is at least as good as serum creatinine to estimate GFR. It is less sensible to changes in body mass. Its determination appears more sensitive to detect early mild changes in GFR. Reference values are presently available for the different methods of determination. Cystatin C plasma level determination is more expensive than routine creatinine plasma determination. In the absence of very significant advantages, this might explain its limited use in daily clinical practice.

[How I investigate ... Alport's syndrome by skin biopsy. When the skin speaks for the kidney]. / Comment j'explore ... le syndrome d'Alport par la biopsie cutanée. Quand la peau parle pour le rein.

Alport's syndrome is a severe hereditary renal disease. Type IV collagen is abnormal in its molecular composition both in the kidneys and the skin. Immunohistochemistry performed on a conventional skin biopsy allows to prove the diagnosis in the affected subjects and in healthy women exhibiting the mutation on a single X chromosome.

[Blood pressure monitoring: dangers and traps]. / La mesure de la pression artérielle: écueils et chausse-trapes.

The measure of blood pressure is probably the the most frequently performed medical act, and the less reliable. The introduction of non invasive recording of ambulatory blood pressure allowed to better define the white coat effect, that is the effect of the presence of a doctor on the blood pressure. White coat hypertension is defined as an abnormal blood pressure in the office and a strictly normal blood pressure outside the medical environment. As such, white coat hypertension is not associated with an increase of cardiovascular morbidity and mortality and thus does not justify drug therapy. However, one third of the patients will progress with time to more severe stages of hypertension.

[Hemolytic uremic syndrome and thrombotic thrombocytopenic purpura]. / Syndrome hémolytique urémique et purpura thrombotique thrombocytopénique.

Hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) are thrombotic microangiopathies (TMA). Both familial and sporadic forms exist: anaemia, thrombopaenia, renal failure and neurologic disorders are common clinical features. The differential diagnosis depends on plasma levels of von Willebrand factor-cleaving protease: there is a deficiency of this protease in patients with TTP whereas its rate is normal in HUS. We remind pathophysiology, etiologies and treatment of these TMA.

[Update on hepatorenal syndrome]. / Le point sur le syndrome hépatorénal.

The hepatorenal syndrome is a form of renal failure occurring in patients with advanced liver disease. The diagnosis is based both on the demonstration of low GFR and exclusion of other common causes of renal failure that may occur in patients with cirrhosis. Orthotopic liver transplantation remains the only curative treatment for this poor outcome disease; other modalities such as vasopressin analogues, transjugular intrahepatic portosystemic shunt or renal replacement therapies may serve as a bridge to transplantation. This article reviews the pathophysiology, diagnosis and current treatment of hepatorenal syndrome.

Belgian peer review experience on the Achille's Heel in haemodialysis care: vascular access.

AIMS: In order to improve the supervision and to evaluate the quality of care in dialysis units, a national project was promoted as a Peer Review. It consisted of systematic, continuous and critical evaluation of the care and the application of international guidelines and compared the reality of care with standards. METHOD: The first chart consisted of the evaluation of infectious episodes of vascular access. This point is particularly relevant since infection represents the second cause of mortality in haemodialysis. A questionnaire concerning each patient was designed. Questions concerned the description of vascular access and the related infectious events. Each questionnaire included 21 items. The project involved 29 dialysis centres, 1,644 patients and 1,775 vascular accesses. The database included 90,525 data. RESULTS: Among the 29 centres, the native arteriovenous fistula (AVF) is the first choice (67.5%) in vascular access, but the proportion of AVF decreases with age contrary to the catheter, which is more frequently chosen, in older patients. Independent of age, 20% of hospitalisations are among patients with catheters and only 7% among patients with AVF. The RR (relative risk) of being hospitalised (any complication of vascular access) is 1.68 for patients with catheters compared to patients with AVF. The rate of infections does not increase with age but is higher for patients with catheters (RR = 2.26). The number of infections appears to be dependent on the staphylococcus aureus carriage in the year. CONCLUSIONS: This first step allows each centre to compare itself to others in an anonymous way. This approach should lead to specific recommendations to improve the quality of care in dialysis units.

Fracture and bone mineral density in hemodialysis patients.

AIM: The aim of this cross-sectional study was to determine in hemodialysis patients the pattern of low trauma fracture, the ability of dual X-ray absorptiometry (DXA) to discriminate between patients with and without fracture, and the magnitude, distribution and mechanism of bone loss. PATIENTS AND METHODS: Eighty-eight patients were studied. Bone mineral density (BMD) was measured by DXA at lumbar spine (LS), femoral neck (FN) and 3 radius sites (UD, MID and 1/3R). In 11 patients (12.5%), 16 fractures occurred and were predominant at the distal forearm and ribs. RESULTS: Patients with fracture had a significatively lower BMD Z-score at LS (-1.34 +/- 1.66 vs -0.42 +/- 1.23), at FN (-1.58 +/- 1.25 vs -0.60 +/- 1.01), at MID radius (-2.59 +/- 1.34 vs -0.93 +/- 1.76) and 1/3 radius (-1.62 +/- 1.60 vs -0.39 +/- 1.32). They also had a longer history of dialysis (113 +/- 64 vs 53 +/- 65 months). Prevalence of osteoporosis varied from 23% at LS to 50% at MID radius. CONCLUSION: Multiple regression analysis showed that there was no influence of gender, age, parathormone status and primary renal disease on BMD. However, at FN, UD, MID and 1/3 radius, a significantly negative correlation was found between length of dialysis and BMD Z-score. By contrast at LS, there was a positive correlation between age at onset of dialysis and BMD Z-score. Despite occurrence of fracture at the fistula forearm, BMD levels were similar in both arms.

[Clinical case of the month. Autosomal dominant polycystic kidney: factors in progression of renal insufficiency]. / Le cas clinique du mois. La polykystose rénale dominante: facteurs de progression de l'insuffisance rénale.

Autosomal dominant polycystic kidney disease is the most frequent genetic renal disease in our population. The variability of the evolution to renal failure, sometimes in the same family has lead to suspect a role for environment factors. In spite of active research, no factor has been identified so far.

[Chronic renal failure: management suggestions based on scientific evidence]. / L'insuffisance rénale chronique: quelle prise en charge proposer selon des critères basés sur les évidences scientifiques.

Chronic renal failure whatever its etiology is a progressive disease, associated with important morbidity and mortality. Most patients will require renal replacement therapies (hemodialysis, peritoneal dialysis or transplantation). An early follow up by nephrologists, an optimal control of hypertension and of the glomerular hyperfiltration syndrome, might allow slowing the rate of evolution of nephropathies. At least, this approach allows to delay complications of renal failure and to improve the patient survival. Guidelines based on scientific studies are presently available to approach the treatment of chronic renal failure.

[Hypertension 2000. Medical guidelines based on scientific evidence]. / Hypertension 2000. Des directives à la médecine basée sur des évidences scientifiques.

The benefit of antihypertensive therapy has been clearly established in mild to moderate as well as in severe hypertension. The benefit appears related to the correction of high blood pressure and the nature of the antihypertensive agents used to reach that goal is of secondary importance, excepted in some specific clinical situations. Additional benefits have clearly been established for the use of betablockers in myocardial infarction, ACE inhibitors in diabetes mainly with proteinuria and proteinuric nephropathies. The availability of different pharmacological classes allows the clinician to personalize the treatment to the individual characteristics of the hypertensive patient.

[Gitelman syndrome: a rare cause of hypokalemia]. / Le syndrome de Gitelman: une cause rare d'hypokaliémie.

We report a case of hypokaliemia whose origin is a urinary potassium loss associated with syndrome of Gitelman. The syndrome of Gitelman is a rare familiar autosomal recessive nephropathy. We will discuss the pathophysiology of this syndrome and differential diagnoses.

Factors determining the percentage of hypochromic red blood cells in hemodialysis patients.

UNLABELLED: Factors determining the percentage of hypochromic red blood cells determines iron status in hemodialysis patients. BACKGROUND: Determination of the percentage of hypochromic red blood cells (RBC; %HYPO) has been advocated as a sensitive index of functional iron deficiency during erythropoietin (EPO) therapy in hemodialyzed patients. METHODS: The significance of %HYPO in chronic renal failure was evaluated in 64 chronically hemodialyzed patients. The linear correlation was determined between %HYPO and 13 variables, including age, sex, weight, C-reactive protein (CRP), ferritin, transferrin (Tf), Tf saturation, soluble Tf receptor (sTfR), serum iron (SI), urea, parathormone, dialysis dose (Kt/V), dose of EPO administered (EPO), and absolute reticulocyte count. Multiple regression analyses were then performed to select the parameters that jointly provide the best prediction of %HYPO. RESULTS: Univariate analysis showed significant correlations between %HYPO and iron parameters (sTfR, Tf saturation, SI, and ferritin, in decreasing order), EPO, reticulocyte count, and CRP. Multivariate analysis yielded an equation showing that the variation of %HYPO is essentially associated with the combined changes in sTfR, CRP, and EPO dosage. CONCLUSIONS: %HYPO is a meaningful and inexpensive parameter that reflects the integrated effects of iron stores, inflammation, and erythropoietic stimulation on iron availability in hemodialyzed patients. Among iron exchange parameters, sTfR is the best predictor of %HYPO, followed by Tf saturation, SI, and ferritin.