Bicarbonate haemodialysis: an adequate treatment for lactic acidosis in diabetics treated by metformin.

Lactic acidosis in diabetics on metformin therapy is rare but still associated with poor prognosis. The authors report here five cases. Three patients were initially with a cardiovascular collapse and all had an acute renal failure. Sodium bicarbonate haemodialysis therapy led to a dramatic improvement. Consciousness and hemodynamic status recovered rapidly. Severe metabolic and blood gases derangements were also rapidly corrected. Plasma metformin removal, appreciated by repeated blood samplings in 3 cases, was satisfactory. All patients survived. However, blood metformin levels remained abnormally high at the end of the dialytic therapy. In conclusion, (1) bicarbonate dialysis is an adequate treatment of lactic acidosis observed in diabetic patients treated with metformin since it rapidly corrects the acid-base disorders and partially removes metformin; (2) the sole accumulation of metformin is not sufficient to explain lactic acidosis since this latter might be corrected in spite of persisting high levels of blood metformin.

Indirect clinical evidence that 1 alpha OH vitamin D3 increases the intestinal absorption of aluminum.

In a previous study we showed that 1 alpha OH vitamin D3 [1 alpha (OH)3] given to 16 hemodialyzed patients taking Al(OH)3 at a constant dose increased their plasma concentrations of aluminum [Demontis et al. 1986]. In order to choose between 2 possible mechanisms explaining this increase (increased intestinal absorption or decreased tissue storage of aluminum), we gave, in the present study, 1 alpha (OH)3 the same dose (6 micrograms per week) for the same period (4 weeks) to 15 stable hemodialyzed patients after their Al(OH)3 had been discontinued for 6 weeks. Under Al(OH)3 treatment they had a mean plasma aluminum (2.33 +/- 2.36 mumol/l) which was not significantly different from that of the patients in our former study (1.23 +/- 0.25 mumol/l). After Al(OH)3 discontinuation, plasma aluminum (measured by inductively coupled plasma emission spectrometry) decreased significantly as early as the 2nd week of the control period (1.39 mumol/l). The decrease was maintained at a plateau throughout the 5 weeks of the control period (1.38 mumol/l), the 4 weeks of 1 alpha OH vitamin (vit) D3 administration (1.40 mumol/l) and the 8 weeks of the post 1 alpha (OH)3 period (1.22 mumol/l). Plasma calcium and phosphate concentrations increased significantly with 1 alpha (OH)3 and decreased thereafter whereas plasma PTH concentrations decreased during 1 alpha (OH)2 D3 and increased after its discontinuation suggesting biological activity of 1 alpha (OH)3. Since 1 alpha (OH)3 increases plasma aluminum in hemodialyzed patients only when they are simultaneously taking Al(OH)3, it is suggested that this increase is explained by an increase of intestinal absorption of aluminum and not by a tissue redistribution of aluminum.

[The renin-angiotensin-aldosterone system and the adrenergic system in normal pregnancy and hypertension induced by pregnancy]. / Le système rénine-angiotensine-aldostérone et le système adrénergique au cours de la grossesse normale et de l'hypertension induite par la grossesse.

Plasma renin activity (PRA), plasma aldosterone (PA) and plasma catecholamines were measured in 3 groups of women with pregnancy of 20-38 weeks: group I of 16 normotensive controls, group II of 17 women with rest responding hypertension (RRH) and group III of 18 women with permanent hypertension (PH) (supine blood pressure greater than 140-90 mmHg after 8 days of rest, disappearing after delivery). Studies were realized on fasting ambulatory women on a normal salt diet. PRA (mean +/- SEM) was significantly higher in the RRH group than in the control and PH groups (15,8 +/- 2,3 ng/ml/h versus 6,7 +/- 0,5 and 8,9 +/- 0,9). PA was higher but not significantly in the RRH group (736 +/- 122 versus 533 +/- 52 and 502 +/- 103 pg/ml). Plasma epinephrine (PE) and norepinephrine (PNE) were significantly higher in the PH than in the control and RRH groups. 135 +/- 28 pg/nl versus 56 +/- 13 and 63 +/- 17 for PE and 387 +/- 91 versus 206 +/- 32 and 200 +/- 47 pg/ml). These data suggest that PH is linked with activation of the adrenergic system whereas RRH is linked with activation of the RAA system.

[Bone locations of systemic mastocytosis: radiological and scintigraphic study (author's transl)]. / Les localisations osseuses de la mastocytose systémique. Etude radiologique et scintigraphique.

Bone radiological signs in six cases of systemic mastocytosis are described: lesions may be diffuse or circumscribed and of the condensation and/or rarefaction type. In most cases, however, the lesions are of the mixed type. Bone mastocytosis may occur without any cutaneous lesions and this emphasizes the value, from the diagnostic point of view, of radiological examinations of the skeleton. Diagnosis is defined and confirmed by three features: the association of condensing lesions and bone rarefactions in different regions of the skeleton; the presence of mastocytic proliferation in stained biopsy specimens from the posterior iliac bone which is not decalcified; fixation of 99m tc pyrophosphate in the axial skeleton on scintigraphy.

[Acute renal insufficiency caused by observed a combination of enalapril, furosemide and flurbiprofen in a patient with retroperitoneal fibrosis]. / Insuffisance rénale aiguë observée sous association énalapril, furosémide et flurbiprofène chez un malade ayant une fibrose rétropéritonéale.

The case of vasomotor parenchymal acute renal failure is reported in a patient a few days after the initiation of treatment by Enalapril which is a new converting enzyme inhibitor. No renal artery stenosis could be demonstrated, which is in contrast with the numerous cases reported up to now. However the helping roles of an incomplete obstruction by a peri-aneurysmal retroperitoneal sclerosis, of prolonged anterior treatment with flurbiprofen and of simultaneous administration of furosemide may be discussed.

Analysis of the optical concentration curve to detect access recirculation.

The optical blood volume curve sometimes presents either a positive or a negative rapid and reversible variation (spike) during the step of the dialysate conductivity, automatically set by the monitor for the ionic dialysance (ID) measurement. We studied whether this feature was in relation with access recirculation. Firstly, we studied if the manoeuvre of reversed position of the blood lines created the same feature in the blood volume curve. Secondly, two medical teams systematically checked for the presence of spikes and measured the access recirculation by way of an ultrasound dilution technique. The manoeuvre of reversed position of the blood lines invariably reproduced the same feature on the curve of the optical blood volume measurement in case of a recirculation greater than 20%. In the normal position of the blood lines, the 16 patients with an access recirculation greater than 20% had spikes. Spikes during ID measurement were not constant for an access recirculation between 10 and 20% and did not occur for an access recirculation of less than 10% or an undetectable one. The special spike of the optical blood volume curve occurring during the ID measurement clearly detects access recirculation. The specificity is of 100% when this modification is present all along the dialysis session for all the ID measurements and the sensitivity is 100% when the access recirculation is greater than 20%.

[Ionic dialysance and quality control in hemodialysis]. / Dialysance ionique et contrôle de qualité de l'épuration en hémodialyse.

Quantification of dialysis is based on the measurement of effective urea clearance (K), dialysis dose (Kt) or normalized dialysis dose (Kt/V). During the last 20 years, Kt/V was the single parameter actually useful for quantifying dialysis efficiency, because it can be calculated from just blood or dialysate urea concentrations at the beginning and at the end of the dialysis session. However the calculation of the normalized dialysis dose (Kt/V) actually delivered to the patient cannot be performed during each dialysis session, because of the need of urea concentration measurements. Ionic dialysance is a new parameter easily measured on-line, non-invasively, automatically and without any cost during each dialysis session by a conductivity method. Because ionic dialysance has been proved equal to the effective urea clearance taking into account cardiopulmonary and access recirculation, it is becoming an actual quality-assurance parameter of the dialysis efficiency.

Portal hypertension in systemic mastocytosis.

We report the case of a 66-year-old male patient with portal hypertension related to systemic mastocytosis. The liver was enlarged; microscopic examination showed portal mast cell infiltration and fibrosis. Portal hypertension was evidenced by splenomegaly, esophageal varices, and increased wedged-free hepatic venous pressure gradient. Arteriography showed that portal vein was patent. Portal hypertension could be the consequence of intrahepatic block due to mast cell infiltration and/or fibrosis of the liver.

[Performance of central catheters on the filtration yield measured by ionic dialysance ]. / Performances des cathéters centraux sur les débits d'épuration mesurés par la dialysance ionique.

Certain number of dysfunctions, particularly decline of blood flow or, recirculation, can decrease the adequacy of depuration, when central catheters are used. Ionic dialysance is available on some monitors (Integra), and reflects perfectly the effective urea clearance, permits to watch any variation in the effective clearance of the depuration system due to these dysfunctions. We report on our experience in a retrospective study from 01/01/2000 to 30/11/2000 where we compared the effective clearance of depuration measured by the ionic dialysance of all the sessions of dialysis made on central catheters in our center, with the forecast clearance of sessions made in the same conditions of dialysis but with a non pathologic fistula. The mean of dialysances decreases of 12% on Dual Cath, of 15% on Ash Split Cath, and 28% on Silicone single lumen femoral catheter, and further analysis makes appear that respectively 60, 65 and 92% of these sessions have a mean of dialysance--10% with regard to the threshold value. The recirculation is certainly the major factor of this decline of the ionic dialysance as well as the decline of blood flow due to partial clotting or relative low venous central pressure due to hypovolaemia. Our data incite to more vigilance for a possible sub dialysis during the use of the central catheters, and prove the utility of the ionic dialysance to watch the technical conditions of the session of dialysis.

Hemodialysis in the treatment of lactic acidosis in diabetics treated by metformin: a study of metformin elimination.

The aim of this study was to determine the characteristics of metformin elimination by dialysis. For this purpose we report the kinetic parameters during dialysis and the metformin clearance (i.e. dialysance) in four patients presenting with lactic acidosis which occurred on metformin therapy. We also studied metformin elimination in two chronically hemodialyzed diabetic patients inadvertently maintained on metformin therapy and in two chronically hemodialyzed non-diabetic patients who took a single dose of metformin before a dialysis session. Analysis of plasma concentration-time curves showed a biphasic pattern of metformin - elimination, according to a two-compartment model. We demonstrate that metformin may be removed even after reaching an equilibrium between blood and dialysate levels in a recirculating system, suggesting a storage of metformin in a deep compartment with a gradient of concentration between this compartment and the blood. Lastly, metformin dialysance appears satisfactory (68 ml/min) even in the case of relatively low blood flow; this value reached 170 ml/min under good hemodynamic conditions. In conclusion, hemodialysis efficiently removes metformin and corrects metabolic acidosis in patients with metformin-induced lactic acidosis.

[Treatment of peritonitis in peritoneal dialysis. Comparison between continuous lavage with a machine and intermittent lavage with 4 CAPD bags/day]. / Traitement des péritonites en dialyse péritonéale. Comparaison entre lavage continu avec machine et lavage intermittent par quatre sacs/jour de DPCA.

Since 1978, 54 episodes of PT occurred in patients treated by PD, first 26 PT (group A) were treated by CLM (40 l/day) and in situ antibiotics (AB): in the absence of Candida, the association of sulfamethoxazol (SMZ: 80 mg/l) and trimethoprime (TMP: 16 mg/l) was used. Only when a Candida was present amphotericine B (AMB: 5 mg/l) was used. CLM was continued until PT was cured. The last 29 PT (group B) were treated by 4 bags/day of CAPD with in situ AB: SMZ: 200 mg/l and TMP 40 mg/l and a systematic oral prophylaxis of Candida was performed by AMB 1,5 g/day. In group A, 5 patients died and 2 others in group B. Complications were more frequent in group A (14) than in group B (6): p less than 0.02. In group A, the AB was changed in 7 cases because of initial resistance (1) or bacterial superinfection (2) or Candida superinfection (4). In group B, AB was changed in 9 cases because of initial resistance (7) or Candida superinfection (2). In conclusion the treatment of PT by 4 bags per day with in situ AB cure PT as rapidly as CLM in spite of lower doses of SMZ - TMP. However, this method is easier to perform and give less complication than CLM. It must be the treatment of choice of PT from peritoneal dialysis.