[Hemodiafiltration with endogenous reinfusion in chronic inflammation: a possible therapeutic alternative?]. / L'impiego dell' Emodiafiltrazione con reinfusione endogena (HFR) nell'infiammazione cronica idiopatica: una possibile alternativa terapeutica?

The patients under maintenance haemodialysis (HD) continue to have an unacceptably excess of mortality compared to general population, that may be explained by high prevalence of inflammation that significantly influences the survival of these patients. Indeed, chronic inflammation is very common in HD and it may cause malnutrition and progression of atherosclerotic disease by several pathogenetic mechanisms triggered by pro-inflammatory cytokines. Currently no pharmacological intervention is specifically targeted the idiopathic chronic inflammation. Hemodiafiltration with endogenous reinfusion (HFR) is a dialysis technique, highly biocompatible, that combines three depurative mechanisms: diffusion, convection and absorption. The ultrafiltrate is obtained from convective section of dialyzer (convection). It is regenerated by passing through the adsorbent macro-porous synthetic resin cartridge (absorption) and then it is reinfused into the second section of the filter (diffusion). This resin cartridge is able to absorb cytokines and other uremic toxins, whereas allows to pass nutrients and antioxidants, as amino acids and vitamins, with a consequent decrement of inflammation and oxidative stress. These characteristics suggest the use of HFR in HD patients affected by overt and idiopathic chronic inflammation. In these patients, we observed that the switching from Bic-HD to HFR allowed an improvement of inflammatory as testified by a significant decrement of serum levels of CRP IL-6, IL-1 and TNF- and a significant increase of albumin and pre-albumin. Whether these favorable effects may modify the outcomes of these high-risk patients, needs to be confirmed by studies ad-hoc.

Intradialytic changes of plasma amino acid levels: effect of hemodiafiltration with endogenous reinfusion versus acetate-free biofiltration.

During hemodialysis, amino acids (AA) are lost in the ultrafiltrate with consequent modification of their plasma profile. The aim of this cross-sectional study was to evaluate intradialytic changes of plasma AA levels during a single session of hemodiafiltration with endogenous reinfusion (HFR) versus acetate-free biofiltration (AFB). 48 patients chronically treated with HFR or AFB were matched 1:1 for age, gender, Kt/V and diabetes. Blood samples were collected at the beginning and the end of dialysis. Baseline plasma levels (µmol/l) of total AA (3,176 ± 722), essential AA (889 ± 221), and branched chain AA (459 ± 140) levels in HFR were similar to those in AFB (3,399 ± 621, 938 ± 277, and 463 ± 71, respectively). Plasma intradialytic AA levels did not change in HFR, while in AFB there was a reduction by about 25%. In conclusion, as compared with AFB, HFR has a sparing effect on AA loss due to the lack of adsorption by cartridge and to their complete reinfusion in blood.

ePTFE soft tissue patch reconstruction of hemidiaphragmatic agenesis with late clinical presentation.

In this paper we describe a case of a 71-year-old man affected by left hemidiaphragm agenesis who presented an extensive enterothorax after an asymptomatic history for many years. The patient had late development of severe constipation and occasional episodes of bowel obstruction and vomiting. The surgical correction of this congenital anomaly consisted of restoring the continuity of the diaphragmatic barrier with a 2-mm-thick expanded polytetrafluoroethylene soft tissue patch(Gore-Tex) after the herniated viscera have been replaced into the abdominal cavity. At 26 months' follow-up no recurrence has been observed. We would suggest that this is the first known elderly patient surgically treated and the eighth case reported in the literature. The use of a single-layer ePTFE mesh allows a good anatomical and functional repair. An overview of the literature is also reported.

Oesophageal achalasia in elderly people: results of the laparoscopic Heller-Dor myotomy.

AIMS: To assess the outcome of laparoscopic Heller-Dor myotomy for oesophageal achalasia in two groups of patients identified by age (under and over 70 years) using functional and clinical instruments. BACKGROUND: Current therapies for achalasia can't restore normal motility but can palliate dysphagia. Many other symptoms may persist difficult to quantify and to compare. In order to understand if age is a factor that influences the therapeutic outcome we tested the reliability of a specific QoL instrument for comparing outcomes of surgery for achalasia. METHODS: Functional examinations and the Gastrointestinal Quality of Life Index (GIQLI) were used before and after laparoscopic Heller-Dor myotomy. RESULTS: Starting in January 1996, 28 consecutive patients of 32 diagnosed (instrumental evidences) achalasia were operated on laparoscopically for various clinical stages of achalasia. In 78% of patients dysphagia disappeared, the incidence of gastro-oesophageal reflux was of 11%. The patients completed a GIQLI questionnaire preoperatively and after a minimum postoperative follow-up of 1 year. Median preoperative GIQLI score was 78(range 38-109) out of a theoretical maximum score of 144. At a median follow-up of 35 months (range 18-72), the score had significantly improved to 115 (range 71-140). All the items assessing gastrointestinal symptoms and physical, social, and emotional function were significantly improved. There is no difference between the two groups identified. CONCLUSIONS: The laparoscopic Heller-Dor myotomy is an effective palliation for acalasia, the medium-term outcome is not affected by the age of the patients. The GIQLI is a reliable instrument to compare the impact of achalasia symptoms on health-related QoL.

Nephrotic edema.

This article starts with a concise synopsis of the history of edema. The role of underfilling, overflow, antidiuretic hormone, and acquaporins is subsequently discussed. Emphasis is given to the use of diuretics in edematous patients. The role and risks of albumin infusion are illustrated. The new hypothesis of pulse reverse osmosis is discussed. The final section deals with the measurement of colloid osmotic pressure in the clinical setting.

A decrease in renal medullary tonicity stimulates anion transport in Henle's loop of rat kidneys.

To investigate the effect of reduction in renal medulla osmolality on loop of Henle (LOH) net bicarbonate reabsorption, clearance and microperfusion experiments were performed on Sprague-Dawley rats. The decrease of renal medulla osmolality was induced by intravenous infusion of either a large dose of mannitol (mannitol protocol) or a hypotonic solution (hypotonic protocol) delivered at a rate to match the sodium and bicarbonate load of the control period. During the mannitol protocol, clearance data demonstrated a rise in glomerular filtration rate (GFR), renal plasma flow, urine pH, and fractional bicarbonate excretion. On the contrary, microperfusion experiments, performed in the absence of mannitol in the tubular perfusate, revealed a significant increase both in the absolute and fractional LOH bicarbonate transport. During the hypotonic protocol, there was a decrease in GFR, associated with an increase in fractional excretion of bicarbonate. In the microperfusion experiments, hypotonic saline, similar to mannitol, stimulated absolute and fractional LOH bicarbonate transport. Net reabsorption of chloride, measured under the same experimental conditions, was also found to be activated. Therefore, the intravenous infusion of hypotonic solution affected the LOH transepithelial net reabsorption of both bicarbonate and chloride. We hypothesize that the increase in the transport rate of these two anions, along the same segment and in similar experimental conditions, may be mediated, at least in part, by decreased medullary tonicity, which is one factor common both to hypertonic mannitol and hypotonic saline infusion.

Update on renal acidification: a physiological view.

The kidney plays a major role in the regulation of acid-base balance. This process is mainly dependent on H+ secretion in the tubular lumen. Two acid extruder proteins are involved: the Na+/H+ exchanger and H(+)-ATPase. Studies using in vivo and in vitro microperfusion and isolated membrane vesicles have clearly demonstrated that the Na+/H+ exchanger is the main mechanism regulating H+ secretion/HCO3- reabsorption along the proximal nephron. Moreover, several reports indicate that this protein is involved in intracellular pH (pHi) regulation. Newer studies using molecular biology techniques have identified at least five isoforms of the Na+/H+ exchanger: NHE-1 is the housekeeping isoform, while NHE-3 seems to be implicated in transepithelial acid-base transport, although other isoforms could be involved too. H(+)-ATPase is the major acid extruder protein along the distal nephron, but it is also expressed along the proximal tubule, where a Na(+)-independent bicarbonate reabsorption has been described. There are a few studies indicating that the proton pump participates in pHi regulation, particularly in the presence of a large acid load. Its absence along the distal nephron may be one of the causes of distal tubular acidosis.

Tubule effects of glomerular hyperfiltration: an integrated view.

An increase in glomerular filtration rate (GFR) induces adaptive changes in tubular function to prevent the urinary loss of water and electrolytes. This is also true for acid-base balance: the increase in filtered bicarbonate load will stimulate H+ secretion at the level of several segments including the proximal tubule, the loop of Henle, and the distal tubule. There is an activation of both the luminal Na+/H+ exchanger and H(+)-ATPase, and basal-lateral Na(+)-HCO3- cotransport which allows an increase in luminal H+ secretion and basal lateral HCO3- exit. The stimulation of electrolyte reabsorption is very important at the level of the thick ascending limb of Henle, a segment that shows consistent hypertrophy in many models of hyperfiltration. Along this segment, increased Na+ and Cl- reabsorption has been found in rats receiving a high-protein diet. The ensuing reduced Na+ and Cl- concentrations, at the level of the macula densa, could weaken the signal responsible for initiating the tubuloglomerular feedback (TGF), thus allowing GFR to increase.

[Role of alkaline phosphatase Regan isoenzyme in prognosis of patients with osteosarcoma]. / Il ruolo dell'isoenzima di Regan della fosfatasi alcalina nella prognosi dei pazienti affetti da osteosarcoma.

The presence of Regan isoenzyme (the heat stable fraction of alkaline phosphatase) in serum of patients with osteosarcoma has been proposed as a prognostic factor indicating the metastatic evolution of the disease. This work reports on 9 patients with osteosarcoma. In 4 of them Regan isoenzyme was present 4, 6, 12, and 16 months before clinical-instrumental evidence of lung metastases. These results further support the significance of this isoenzyme as a marker of relapse in an early subclinical stage.