[A lie which became the truth]. / Una bugia diventata verita'

We describe a 54 year-old lady, on dialysis since 6 years, with severe hyperparathyroidism and multinodular goiter. After total thyroidectomy and subtotal parathyroidectomy a Tc-99 scan revealed multiple bone lesions consistent with metastatic disease. In the following weeks the patient general conditions and bone pain markedly improved and alkaline phosphatase returned to normal levels. Biopsy of a bone lesion revealed that the scintigraphic pattern was a false positive result due to hyperparathyroidism.

[From CANUSA to ADEMEX: do we need a new paradigm for definition of peritoneal dialysis adequacy?]. / Dal CANUSA all'ADEMEX: è necessario un nuovo paradigma per definire l'adeguatezza della dialisi peritoneale?

Peritoneal dialysis doses were prescribed out of empirical criteria up to the mid-Ninety Then, the observational CANUSA study and the experimental ADEMEX study helped to define adequacy criteria according to urea kinetics model. This review analyzes the limits of a definition of adequacy grounded exclusively on urea kinetics, as well as the need for new parameters of adequacy. The evidence is presented fostering the hypothesis that the control of extra-cellular fluid excess and of other cardiovascular risk factors may now be considered a new target for adequacy.

[Oscillometric wrist devices: comparison with the standard mercury sphygmomanometer and estimate of the "supine" error]. / La misura oscillometrica della pressione al polso: confronto con il metodo sfigmomanometrico classico e valutazione dell'errore di posizione del polso col paziente supino.

Before introducing a wrist device (NAIS-Matsushita) for blood pressure (BP) measurement in our Unit, we formally tested its validity. Since the wrist position is critical and BP in the clinical setting is often measured with patients lying in bed, we also estimated the error introduced by allowing the wrist to lay flat at the bed level. Ten normal subjects and 20 hypertensive patients took part in two consecutive studies. In the first study the subjects were sitting and the blood pressure was simultaneously taken with the auscultatory mercury sphygmomanometer on the left arm and with the NAIS on the right wrist. The wrist was kept at the heart level. In the second study two NAIS devices were used with the subjects lying in bed; the left wrist was allowed to stay at the bed level, while the right one was kept at the heart level. The diastolic BP was consistently underestimated (P< 0.001) by the wrist device (79 mmHg 95%CI: 75-83) as compared to the values obtained with the standard mercury sphygmomanometer (85 CI: 79-88). No significant difference was found in systolic BP (mercury: 135 CI: 127-143; wrist 134 CI: 126-141). In the second study the BP (systolic and diastolic) was markedly higher (P<0.001) when the wrist was kept at the bed level (systolic bed level: 144 CI: 135-152; systolic heart level: 135 CI:126-141; diastolic bed level: 83 CI:78-88; diastolic heart level: 76 CI:71-79).

Long-term CAPD patients are volume expanded and display more severe left ventricular hypertrophy than haemodialysis patients.

BACKGROUND: Whether hypertension and left ventricular hypertrophy (LVH) are more prevalent in CAPD than in haemodialysis (HD) patients is still under discussion. METHODS: To examine this problem we compared a group of 51 CAPD patients, with a group of 201 HD patients. The evaluation included the measurement of atrial natriuretic peptide (atrial natriuretic factor (ANF)), taken as indicator of volume status, and echocardiographic measurements. RESULTS: CAPD patients were older, had been treated for a shorter time, and had lower serum albumin and phosphate than HD patients. Plasma ANF was higher (P<0.01) in CAPD (median 33.8 pmol/l (interquartile range 18.2-63.0)) than in HD patients (22.7 pmol/l (14.9-38.7)). Similarly, the left atrial volume was substantially higher (P<0.0001) in CAPD patients (49+/-22 ml) than in HD patients (37+/-17 ml), while the left ventricular end-diastolic diameter was similar in the two groups (CAPD 51+/-7 mm; HD 50+/-7 mm). Furthermore, left ventricular hypertrophy was more severe (P<0.0001) in CAPD (157+/-37 g/m(2)) than in HD patients (133+/-39 g/m(2)). The proportion of CAPD patients requiring antihypertensive drugs was markedly higher than that of HD patients (65 vs 38% P<0.001). Multivariate modelling showed that volume expansion and pressure load as well as serum albumin were independent predictors of left ventricular mass. CONCLUSIONS: Left ventricular hypertrophy is more severe in long-term CAPD patients than in HD patients. This finding is associated with evidence of more pronounced volume expansion, hypertension, and hypoalbuminaemia. Volume and pressure load along with factors associated with hypoalbuminaemia may aggravate LVH in uraemic patients on CAPD.

Nocturnal hypoxemia, night-day arterial pressure changes and left ventricular geometry in dialysis patients.

It is well established that nocturnal hypoxemia in sleep apnea causes an inversion of the circadian arterial pressure rhythm and triggers nocturnal hypertension. Since sleep apnea is very frequent in dialysis patients, we hypothesized that nocturnal hypoxemia may be a factor that contributes to alter the 24-hour arterial pressure profile in these patients. To test the hypothesis 32 dialysis patients underwent 24-hour blood pressure (BP) monitoring and continuous monitoring of arterial O2 saturation during the night-time. Hemodialysis patients were studied during the non-dialysis day. All patients underwent an echocardiographic study. Thirteen patients had no episode of nocturnal hypoxemia (group I), 7 had at least one episode overnight but less than 2 episodes/hr (group II) and 12 had > or = 2 episodes/hr (group III). The average daytime systolic pressure was similar in the three groups. However, the average nocturnal systolic pressure fell in the first group (-2.5 +/- 4.2%) and rose in the second (+2.0 +/- 3.6%) and in the third (+3.9 +/- 2.2%) group (one way ANOVA, P < 0.005). The relative wall thickness of the left ventricle (RWT) was significantly (P < 0.05) higher in group III than in group I, and in the aggregate (N = 32) there was an inverse relationship between average nocturnal SaO2 and RWT (r = -0.43, P = 0.015). The proportion of patients with concentric remodeling or concentric hypertrophy was higher (P = 0.05) in the group with a more severe degree of nocturnal hypoxemia (group III, 8 of 12) than in the other two groups (group I, 3 of 13; group II, 2 of 7). Nocturnal hypoxemia is associated with the "non-dipping" arterial pressure profile in dialysis patients. Disturbed respiratory control during the night may represent an important cardiovascular risk factor in dialysis patients.

DOQI guidelines in peritoneal dialysis. Dialysis outcome quality initiative.

The DOQI initiative produced 32 guidelines for peritoneal dialysis. The guidelines on adequate dose of peritoneal dialysis and criteria for starting dialysis treatment constitute the core of the document and are expected to have the most important impact on clinical practice. These guidelines are based mainly on circumstantial evidence and observational studies, thus they must be considered for what they are, i.e. useful operational tools open to discussion and not absolute truth. The potential impact of the DOQI guidelines in a dialysis programme is shown using the anthropometric data of 1061 adult patients on file in the Calabrian Registry of Uremia, Dialysis and Transplantation.

Cross-sectional comparison of malnutrition in continuous ambulatory peritoneal dialysis and hemodialysis patients.

Although malnutrition is not uncommon in continuous ambulatory peritoneal dialysis (CAPD) and maintenance hemodialysis (MHD) patients, there has never been a large-scale comparison study of nutritional status with these two dialysis modalities. We therefore assessed protein-calorie nutrition in 224 CAPD patients and 263 MHD patients who were treated in eight centers in Italy. The CAPD patients were slightly older than the MHD patients (60.2 +/- 14.2 years v 56.3 +/- 15.1 years; P < 0.01), had undergone dialysis for less time (2.32 +/- 2.10 years v 3.66 +/- 2.66 years; P < 0.0001), and had higher residual renal function (1.83 +/- 2.29 mL/min v 0.27 +/- 0.91 mL/min; P < 0.0001). Protein nitrogen appearance was 60.5 +/- 16.6 g/d and 61.9 +/- 16.5 g/d in the CAPD and MHD patients, respectively. In CAPD versus MHD patients, serum total protein and albumin tended to be lower; serum transferrin and midarm muscle circumference were similar; and relative body weight, skinfold thickness, and estimated percent body fat tended to be greater. These greater values in CAPD patients were particularly evident in those who were 65 years of age or older. Serum glucose, total cholesterol, and triglycerides also were greater in CAPD patients. The subjective global nutritional assessment indicated a significantly greater proportion of malnourished CAPD patients than MHD patients (42.3% v 30.8%). The greater prevalence of malnutrition in CAPD patients diminished with age. Maintenance hemodialysis patients older than 76 years were more likely to be malnourished than CAPD patients. In patients less than 65 years of age, protein-calorie malnutrition was more likely to be present in CAPD patients than in MHD patients.

Nutritional status in the elderly patient with uraemia.

An increasing number of elderly patients with uraemia are treated by dialysis therapy. Virtually every published study on nutritional status of patients undergoing maintenance haemodialysis treatment or continuous ambulatory peritoneal dialysis (CAPD) has indicated that a substantial proportion of patients undergoing regular dialysis treatment have protein calorie malnutrition. Problems of undernutrition increase significantly with age; a combination of socioeconomic, psychological, and biochemical problems interfering with acquiring and assimilating a balanced diet are responsible for nutritional deficiencies in older people. We assessed the prevalence of protein calorie malnutrition in 183 regular dialysis patients aged 65 years or older treated with haemodialysis or CAPD. This group of patients was compared to two other groups aged 18-40 years (62 patients) and 41-64 years (239 patients). Presence of malnutrition was assessed by selected serum chemistries, anthropometry and Subjective Global Nutritional Assessment. Adequacy of dialysis, protein nitrogen appearance, as an index of protein intake, and residual renal function were measured. The results indicate that protein calorie malnutrition occurs commonly in regular dialysis patients, with a higher prevalence of malnutrition in the elderly; 51% of patients of the elderly group were classified as malnourished, and no difference was found with the two dialytic modalities.

Subjective global assessment of nutrition in dialysis patients.

Malnutrition is a major negative prognostic factor in dialysis patients. Simple and reliable estimations of nutritional status may therefore prove of particular value in the follow-up of these patients. To validate subjective global assessment (SGA) in dialysis patients we compared subjective global assessment with objective measurements (anthropometry, bioelectrical impedance, biochemical measurements) in 59 chronic uraemic patients treated by haemodialysis (n = 36) or CAPD (n = 23). Subjective global assessment was performed by an observer unaware of the results of objective measurements and was related to serum albumin (r = -0.51, P < 0.001) and bioelectric impedance phase angle (r = -0.58, P < 0.001) as well as with MAMC (r = -0.28 P = 0.028), %fat (r = -0.27, P = 0.042) and nPCR (r = -0.29 P = 0.027). Multiple regression analysis showed that the relationship of subjective global assessment (as a dependent variable) with objective measurements (covariates) was stronger (multiple r = 0.77) than the relationship found with univariate analysis. This finding indicates that subjective global assessment gives a well-based and balanced estimation of nutritional status. Our data show that subjective global assessment is a clinically adequate method for assessing nutritional status in dialysis patients. Being an inexpensive method of well-proven reliability, subjective global assessment can be recommended for a more frequent assessment of nutritional status in dialysis patients.

Genetic mapping in the Xp11.2 region of a new form of X-linked hypophosphatemic rickets.

Human X-linked dominant hypophosphatemic rickets (HPDR I) is characterized by hypophosphatemia, hyperphosphaturia, abnormal vitamin D metabolism, and rickets/osteomalacia. Two closely linked hypophosphatemic genes, hypophosphatemia (Hyp) and Gyro (Gy), are known on the mouse X chromosome. The Hyp phenotype is the equivalent of the human X-linked hypophosphatemia, while the human equivalent of the Gyro mouse has not been unambiguously identified. We observed an Italian four-generation pedigree with a new form of X-linked recessive hypophosphatemic rickets (XLRH). We demonstrated that HPDR I and XLRH are two different X-linked genes and that XLRH maps in the Xp11.2 region at 0% recombination fraction from the DXS1039 locus. We discuss this new finding in relation to the identification of the human equivalent of the Gyro mouse and to the recent mapping in Xp11.22 of another X-linked recessive renal disorder named Dent disease.

[Prevalence of insulin-dependent and non-insulin-dependent diabetes among Italian patients on replacement therapy. Preliminary survey at 3 dialysis centers]. / Prevalenza del diabete insulino e non insulino-dipendente nei pazienti Italiani in terapia sostitutiva. Indagine preliminare su tre Centri Dialisi.

We carried out a retrospective survey to assess prevalence and type of diabetes in three Italian Renal Units located respectively in the North (Tradate, Varese), in the Middle (Latina) and in the South (Reggio Calabria) of Italy. The prevalence of diabetes among patients accepted for RRT was 10.5% (60/659). 40 patients (66.7%) were non-insulin dependent and only 6 patients were insulin-dependent. A similar pattern was observed among the 289 patients referred to the Renal Unit of Reggio Calabria during 1972-1987 for evaluation of Chronic Renal Failure. Our data suggest that among the Italian diabetic patients treated by dialysis and transplantation insulin-dependent diabetes is uncommon. This finding could be explained by the low incidence of insulin-dependent diabetes in Italy.