[Amiodarone-induced optic neuropathy: A rare side effect]. / Un effet indésirable rare de l'amiodarone : la neuropathie optique.

INTRODUCTION: The diagnosis of bilateral papilledema implies emergency medical care to look for intracranial hypertension and arteritic ischemic neuropathy. However, other causes must also be mentioned, including drugs. Too often underrated because of their usual benignity, drug side ophthalmological effects can be severe and are typically bilateral. CASE REPORT: An 80-year-old woman was hospitalized for bilateral papilledema, predominantly in the left eye, with lowered visual acuity. After ruling out intracranial hypertension, arteritic ischemic optic neuropathy, non-arteritic, and inflammatory bilateral papilledema, the diagnosis was toxic optic neuropathy. CONCLUSION: Bilateral edematous optic neuropathy is a known side effect of amiodarone, uncommon but to be known because of the large number of patients benefiting from this treatment.

Influence of the hydration state on blood pressure values in a group of patients on regular maintenance hemodialysis.

The pathophysiology of hypertension in patients on renal replacement therapy is not yet clear, and the role of extracellular fluid overload is still a matter of debate. The main problem is the lack of techniques to determine the fluid state. Recently new noninvasive techniques have become available which make it possible to accurately determine the hydration state in these patients. We have studied the influence of the hydration state on interdialytic blood pressure in 45 patients: 21 (46.6%) using antihypertensive medication and 24 (53.4%) without antihypertensive medication. Total body water (TBW) was determined by bioelectrical impedance analysis performed just before a hemodialysis session. The TBW was then related to the fat-free mass calculated by the anthropometric method (aFFM) of Durnin. The hydration state was defined using the following formula: TBW/aFFM 100. Furthermore, for each patient the ideal TBW was calculated according to the Watson formula. The difference between TBW and ideal TBW was considered a further index of the hydration state. Ambulatory blood pressure monitoring was performed by using a Takeda 24200 recorder according to the Korotkoff method during the 24 h before the midweek hemodialysis session. Blood pressure monitoring showed a significant correlation with the hydration state of these patients. In conclusion, the hydration state seems to play a major role in interdialytic blood pressure control.

[Epidemiology and clinical course in hepatitis C-positive patients treated with dialysis in Piemonte. Work group of the RPDT]. / Epidemiologia e comportamento clinico nei pazienti epatite C positivi in dialisi in Piemonte. Gruppo di lavoro dell' RPDT.

The high prevalence of HCV positivity in dialysis patients has recently prompted several studies on this controversial subject. The aim of the study was an evaluation of HCV positivity and of influence on clinical outcome in 2,404 patients on dialysis in Piedmont (Northern Italy Region, about 4,400,000 inhab., 20 Dialysis Centers) at December 1993 (32.7% HCV-positive according to the Regional Registry of Dialysis and Transplantation). As expected, a strong correlation was found with time on dialysis (94.4% in patients with treatment follow-up > or = 20 years) and blood transfusions (41.3% HCV positivity in transfused patients versus 22.6% in not transfused ones; p < 0.0001). Dialysis in a hospital setting is confirmed as at high risk of infection, since HCV positivity was 19.6% in patients always treated by bicarbonate dialysis in hospital versus 8.9% in those treated only by CAPD (start of dialysis in 1992-1993). Despite the high prevalence of HCV positivity, however, death rates for liver disease and for all gastrointestinal causes are very low, regardless of HCV antibody status (1.2% in HCV positive versus 2.3% in HCV negative, NS). Whether this depends upon different clinical features of HCV infection in dialysis patients or merely deflects a relatively short follow-up will be matter of discussion in the future.

Monitoring of central venous dual-lumen catheter placement in haemodialysis: improvement of a technique for the practising nephrologist.

Mismanagement in the placement of central venous catheter (CVC) may occur in up to 20% of cases. The catheter can be inadvertently placed in the contralateral brachiocephalic vein, the ipsi or contralateral internal jugular vein, and usually a thoracic radiograph is necessary to evaluate its location. We propose a technique first described by Serafini et al. to establish the position of a CVC by endocavitary electrocardiography (EC-ECG) and its employment in a large number of uraemic patients requiring haemodialysis. This technique uses the tip of the CVC as reference lead in a standard electrocardiograph. The best employment of this technique has been obtained by echotomographic visualization of the internal jugular vein executed just before transcutaneous puncture of the vessel. For 13 months we have successfully applied this technique in CVC placement in 81 patients requiring haemodialysis. In our opinion this method is a safe and simple technique that avoids the need for thoracic radiographs and time lost waiting for radiographs that prolong the start of the haemodialysis session. According to our experience, we confirm that the EC-ECG technique provides a method for ensuring compliance with Food and Drug Administration guidelines regarding catheter tip location in uraemic patients.

Monitoring of central venous dual-lumen catheter placement in haemodialysis: improvement of a technique for the practising nephrologist.

Mismanagement in the placement of central venous catheter (CVC) may occur in up to 20% of cases. The catheter can be inadvertently placed in the contralateral brachiocephalic vein, the ipsi or contralateral internal jugular vein, and usually a thoracic radiograph is necessary to evaluate its location. We propose a technique first described by Serafini et al. to establish the position of a CVC by endocavitary electrocardiography (EC-ECG) and its employment in a large number of uraemic patients requiring haemodialysis. This technique uses the tip of the CVC as reference lead in a standard electrocardiograph. The best employment of this technique has been obtained by echotomographic visualization of the internal jugular vein executed just before transcutaneous puncture of the vessel. For 13 months we have successfully applied this technique in CVC placement in 81 patients requiring haemodialysis. In our opinion this method is a safe and simple technique that avoids the need for thoracic radiographs and time lost waiting for radiographs that prolong the start of the haemodialysis session. According to our experience, we confirm that the EC-ECG technique provides a method for ensuring compliance with Food and Drug Administration guidelines regarding catheter tip location in uraemic patients.

Longitudinal assessment of body composition in continuous ambulatory peritoneal dialysis patients using bioelectric impedance and anthropometric measurements.

We assessed the utility of bioelectric impedance analysis (BIA) and anthropometry for longitudinal evaluation of body composition in continuous ambulatory peritoneal dialysis (CAPD) patients. Eleven subjects were studied at the beginning of CAPD and again at regular intervals during the first 6 months of treatment. The significant weight gain that occurs in our patients is mainly due to a rise in total body water (TBW), as measured by BIA, during the first weeks of CAPD, and later on due to a body fat increase. Anthropometry seems more reliable than BIA in the evaluation of body mass, because the latter is derived from TBW in BIA. Therefore, any change in TBW that occurs in a CAPD patient necessarily causes a similar change in the fat-free mass. In our experience, only the combined use of both anthropometry and BIA allows a proper assessment of body composition in patients on CAPD.

[Arterial hypertension secondary to Conn's disease: an infrequent pathology in nephrology. Report of a clinical case]. / Ipertensione arteriosa secondaria a morbo di Conn: una patologia di non frequente osservazione nefrologica. Presentazione di un caso clinico.

In this work we describe a case of Conn's syndrome caused by a suprarenal adenoma in a sixty-one year female. The patient had come to our observation because of severe hypertension and hypokalemia. Primary aldosteronism resulting from the secretion of excessive amounts of aldosterone caused by autonomous hyperfunction of the adrenal cortex usually by a solitary adenoma. In most series of unselected patients, it is found in fewer than 0.5% of hypertensives. In our study we demonstrated the circadian changes of arterial blood pressure but we failed to demonstrate the presence of hypertrophic cardiomyopathy as recently emphasized in the literature. Regardless of its rarity, primary aldosteronism is a fascinating disease, protean in its manifestations, logical in its pathophysiology.

Hepatitis B vaccination in uremic patients: comparison between recombinant and plasma-derived vaccine.

The immune response to recombinant and plasma-derived vaccines was evaluated in 53 and 43 uremic patients, respectively. The total rate of seroconversion was around 80% with both vaccines, although a significantly higher response was obtained with the protocol using recombinant vaccine.

[Protein metabolism and nutritional status in hemodialysis]. / Metabolismo proteico e stato nutrizionale in emodialisi.

We have studied protein metabolism and nutritional status in a group of patients in regular dialysis treatment. In forty-five patients (mean age 58 +/- 11 yr), undergoing maintenance hemodialysis we have measured protein (DPI) ad caloric (CI) intake by a three-day dietary recall. Protein catabolic rate (PCR) using the urea kinetic model (Gotch' variable volume), anthopometric parameters such as weight, height, midarm circumference, skinfold thickness, midarm muscle circumference (AMC), midarm muscle area (AMA), total muscle mass (TMM) and the percentage of body fat were measured as well. PCR was weakly correlated with DPI. TMM showed a direct relationship with DPI and correlated inversely with UNA/NI (Urea Nitrogen Appearance/Nitrogen Intake). 18% of patients were underweight; 17% showed a decrease of AMA. TMM was inversely correlated with total hospitalization days. There were no significant variations of the examined parameters in a year later evaluation. In our experience TMM is the parameter which better correlates with clinical findings.

Cimetidine does not influence cellular immunity in patients with chronic renal insufficiency.

Numerical and functional markers of peripheral lymphocytes were adopted to study the influence of cimetidine on the immune response in immunocom-promized patients. Twenty-three patients on regular dialysis treatment, who had been given cimetidine (400 mg daily) for peptic ulcer, were studied during a follow-up of 3 months. Thirty healthy people served as controls for the study of the immunological parameters, i.e. DNCB and PPD skin tests, E-rosetting assays, monoclonal antibodies to T-cells, membrane immunoglobulins for the B-cells, serum immunoglobulins and complement. Before therapy was started CMI was impaired in all patients, with a significant reduction in the E-rosette count (P less than 0.01) and depressed DTH (DNCB, PPD). The number of active E-rosettes and OKT4 subsets increased slightly during the period of treatment, though this finding was not confirmed by functional in vivo tests. No change was observed in the B-lymphocyte count and in serum immunoglobulins or complement. The fact that treatment with cimetidine does not seem to influence the immune response in patients on RDT, may suggest that this therapy does not restore the principal immunopathological disorder of these patients, and further justifies its use in patients awaiting renal transplantation or in those who have been given transplant.

The influence of blood transfusion on cellular immunity.

To evaluate the effect of transfusion on immunity, we studied some immunological parameters in 14 uremic patients treated with 3 blood transfusions (5 with HLA-compatible and 9 with random transfusions). Before transfusions 8/14 patients were DNCB-negative; both spontaneous and active E-rosettes were below normal range. The parameters of humoral immunity (S-Ig, C3, C4, IC, CRP) were normal. After both the first and second transfusions an increase in T- and B-lymphocytes was found. The third transfusion led to a more pronounced and prolonged immunosuppression in patients treated with compatible transfusions than in those treated with random transfusions. Our findings suggest that blood transfusion--HLA-compatible transfusion in particular--results in an impairment of the lymphocyte role.