[Acute renal failure after videolaparoscopic surgery: an avoidable complication?]. / L'insufficianza renale acuta postchirurgia laparoscopica: evitabile complicanza?

Videolaparoscopic surgery exposes the abdominal organs to the mechanical effect of pneumoperitoneum at pressure values between 12 and 15 mm Hg, which are considered safe. Nevertheless, experimental data have shown that this pressure range can represent a hemodynamic risk factor as it may induce a decrease in the venous return to the right ventricle, a decrease in cardiac output, and activation of the sympathetic nervous system and renin angiotensin system. We report two cases of acute renal failure that occurred soon after videolaparoscopy in young female patients without any evidence of ongoing renal disease. Patient A was 29 years old and was submitted to videolaparoscopic surgery in a follow-up program after surgical treatment of ovarian cancer; patient B was 15 years old and was submitted to the surgical removal of a monolateral ovarian cyst. In neither of the cases was it necessary to perform hemodialysis. Patient A underwent a renal biopsy under ultrasound guidance; optic microscopy showed only in ra- and extraglomerular capillary congestion. In both cases the acute renal failure resolved completely and the patients where discharged with normal renal function. Taking in to account that normal renal venous pressure levels are around 4 mmHg we think that a) a 15 mmHg pneumoperitoneum may represent a risk factor during videolaparoscopic surgery mainly if the patient's extracellular volume is not properly expanded; b) administration of nonsteroidal anti-inflammatory drugs in order to prevent surgical pain may inhibit vasodilatory prostaglandin availability; c) onset of oliguria during the surgical procedure suggests that extracellular volume expansion is required.

Prolactin releasing and luteinizing hormone inhibiting activity of dermorphin shorter homologues in the rat.

Dermorphin, a heptapeptide isolated from the skin of the frogs Phillomedusa sauvagei and Phillomedusa rhodei, is endowed with potent peripheral and central opioid-like activity. Intracerebroventricular (icv) injection of dermorphin (31.2, 62.5 and 125 pmol/100g) induced in ovariectomized (OVX) rats dose related rises and decreases in prolactin (PRL) and luteinizing hormone (LH) levels, respectively. The aim of this work was to evaluate the same endocrine responses after administration of shorter peptide amide homologues, related to the N-terminal sequence of dermorphin. These compounds retain a substantial analgesic activity although the latter decreases with the decrease in the number of amino acid residues. Icv administration of the hexapeptide homologue (dermorphin 1-6 amide) to OVX rats did not induce any PRL rise or LH inhibition, even at the high dose of 250 pmol/100g. The pentapeptide (dermorphin 1-5 amide), instead, increased PRL and decreased LH secretion, although the effect was significant only at the dose of 250 pmol/100g. Administration of the tetrapeptide (dermorphin 1-4 amide) induced a significant PRL rise and LH inhibition at both the doses of 125 and 250 pmol/100g. The tetrapeptide was the smallest fragment of the dermorphin moiety which caused endocrine responses while the tripeptide (dermorphin 1-3 amide) was completely ineffective in this context. These data indicate that a complete dissociation exists between the behavioral and endocrine effects of the dermorphin homologues examined. In fact, shorter dermorphins whose analgesic potency was directly related to the number of amino acids, exhibited an opposite pattern in evoking endocrine effects.

Ultrastructure analysis of Tenckhoff chronic peritoneal catheters used in continuous ambulatory peritoneal dialysis patients.

The luminal and external surfaces of 18 curled silicone double-cuff catheters removed from patients who had been on continuous ambulatory peritoneal dialysis (CAPD) for 2-77 months (average 37 +/- 21 months) were analyzed by scanning electron microscopy (SEM) and microbiological cultures. Eight catheters (G1) were removed due to recurrent peritonitis or peritonitis refractory to antibiotic management, and the others (G2) due to local or clinical problems. The peritonitis rate was one episode every 24 patient-months in G1, and 80 patient-months in G2. All catheter surfaces were covered with proteinlike granular deposits (0.15 +/- 0.11/cm); 6 catheters were covered by microbial biofilm (0.24 +/- 0.16/cm). Positive cultures of catheter segments were obtained in 6 cases (4 for G1 and 2 for G2) with a preponderance (33%) of Staphylococcus aureus among the cultivated bacteria. Structural defects and small linear tears were present on both luminal and external surfaces in 8 catheters. Structural defects were frequent in the catheters removed for recurrent peritonitis. Linear tears appeared more frequently in the catheters used for a longer time. Structural defects of catheter surfaces were also discovered in the newer devices. The structural defects of the catheter appear to facilitate microbial adhesion and colonization and to predispose the patient to recurrence of peritonitis. A better catheter design and an improvement in the production process should therefore be recommended.

Persistence of a defective tuberoinfundibular dopaminergic function in rats after long-term removal of oestrogen treatment. An in vivo study.

The function of the tuberoinfundibular dopaminergic (TIDA) neurons of 49 rats bearing oestradiol-valerate (EV)-induced prolactin (Prl) secreting tumours (prolactinomas) was evaluated in vivo, 7 months after discontinuation of EV-treatment, with neuroactive drugs acting via stimulation or inhibition of DA neurotransmission. Based on the size and morphologic appearance of the pituitary and on determination of plasma Prl levels, rats previously treated with EV could be divided into those bearing macro- (31/49) and those bearing micro-prolactinomas (18/49). Administration of the indirect DA agonist drug nomifensine (10 mg/kg iv) lowered plasma Prl levels in control rats, but failed to do so in rats bearing either macro- or microprolactinomas. Administration of the DA receptor antagonist domperidone (50 micrograms/kg ip) or the synthetic enkephalin analogue FK 33-824 (1 mg/kg ip) failed to induce a rise in plasma Prl in rats with macro-, but induced a clear-cut rise in plasma Prl in those with microprolactinomas. Prl unresponsiveness to all three neuroactive drugs indicates that long time after EV withdrawal TIDA neuronal function is still highly impaired in rats bearing EV-induced macroprolactinomas. The impairment of TIDA neuronal function would be of lesser extent in rats bearing microprolactinomas as revealed by a defective response to only one of the three applied neuroendocrine probes.

Low doses of drugs able to alter intestinal mucosal permeability to food antigens (5-aminosalicylic acid and sodium cromoglycate) do not reduce proteinuria in patients with IgA nephropathy: a preliminary noncontrolled trial.

In an uncontrolled trial, patients with IgA nephropathy (IgAN) were treated with drugs that can alter the intestinal mucosal permeability to food antigens. These drugs are known to ameliorate urinary abnormalities and histological lesions of IgAN associated with ulcerative colitis or Crohn's disease [5-aminosalicylic acid (5-ASA)] or to prevent, in mice, the induction of IgAN-like disease by oral immunization [disodium cromoglycate (SCG)]. Nine patients [serum creatinine (s-Cr) less than 2 mg/dl; 24-hour proteinuria higher than 1.5 g, but not nephrotic) were treated with 5-ASA (2.4 g/day for 6 months); 9 similar patients were treated with SCG (400 mg/day for 6 months); the follow-up extended to 6 months after stopping therapy. The 5-ASA group showed a slight but not significant decrease in s-Cr, 24-hour/proteinuria, IgA circulating immune complexes (IgA-CIC) and IgA rheumatoid factor (IgA-RF); serum beta 2-microglobulin and serum IgA were unchanged; 2 of 9 treated patients showed, after 6 months of therapy, a reduction in proteinuria of more than 50% that lasted for the subsequent 18 months. The SCG-treated group showed a slight but not significant increase in 24-hour proteinuria and a significant decrease in serum IgA; unchanged were s-Cr, IgA-CIC, IgA-RF, serum beta 2-microglobulin; no patient treated with SCG showed a reduction in proteinuria of more than 50%. At the dosages and for the periods used, 5-ASA and SCG did not show a significant influence on clinical and laboratory parameters of disease in IgAN; other trials with increased dosages are warranted to definitely ascertain the possible therapeutic role of these drugs in IgAN.

Prevalence of hyperlipidemia in a cohort of CAPD patients. Italian Cooperative Peritoneal Dialysis Study Group (ICPDSG).

An association between hyperlipidemia and cardiovascular disease is well described in the literature. We conducted an observational study in order to evaluate the lipid profile, the prevalence of hyperlipidemia and its relationship with age, sex, duration of CAPD, peritoneal glucose load (PGL), serum albumin (ALB), serum glucose (GLU), and BMI in a large cohort of uremics undergoing long-term treatment with CAPD. 457 nondiabetic patients (245 males, 212 females; mean age 63.8 +/- 11.9 years; mean duration of CAPD: 41.8 +/- 26.9 months) treated during 1992 in 25 centers participating in the Italian Cooperative Peritoneal Dialysis Study Group (ICPDSG) were studied. The serum lipid parameters evaluated were triglycerides (TG), total cholesterol (CHO), HDL-cholesterol (HDL). Indications given in the New England Journal of Medicine, SI Unit Conversion Guide, 1992, were adopted for normal ranges. In the whole population the evaluation of lipid parameters showed: TG 227.4 +/- 123.3 mg/dl, CHO 232.8 +/- 56.0 mg/dl, HDL 40.7 +/- 12.0 mg/dl. No differences were found between the two sexes with regard to age, BMI, duration of CAPD, distribution of renal diseases, TG, ALB, and GLU; whereas CHO and HDL were significantly lower in males than in females (CHO: 222.2 +/- 53.5 vs. 245.0 +/- 56.5 mg/dl, p < 0.001; HDL: 39.3 +/- 11.4 vs. 42.6 +/- 12.6 mg/dl, p < 0.05). The prevalence of hypercholesterolemia was significantly lower in males than in females (19.7 vs. 35.4%; p < 0.001). The multiple regression analysis indicated that TG were directly correlated to PGL (p < 0.05), and HDL was inversely correlated with TG (p < 0.001). The coexistence of the two variables (TG and HDL) may increase the risk of cardiovascular events. Further strategies should therefore be developed to select and manage CAPD patients to reduce the incidence of hyperlipidemia.