Transmission of Pneumocystis carinii from AIDS patients to other immunosuppressed patients: a cluster of Pneumocystis carinii pneumonia in renal transplant recipients.

Five renal transplant recipients developed Pneumocystis carinii pneumonia (PCP) over a 22-month period, while no cases had been observed over a 5-year period in 114 transplanted patients treated with the same immunosuppressive protocol. All patients were HIV-negative, and no modification in diagnostic techniques for P. carinii could account for this observation. All five patients developed PCP within 2 months of an acute graft rejection episode. All of them attended the same outpatient facility as AIDS patients attending the hospital, where they shared the waiting and treatment rooms. Comparison of cases with matched controls was possible in three instances and revealed that the cases had had more outpatient clinic encounters with AIDS patients who had presented, or subsequently developed, PCP. This observation suggests that AIDS patients developing PCP may transmit the infection to other immunosuppressed patients.

Postprandial hepatic glycogen synthesis in liver transplant recipients.

BACKGROUND: The liver plays a central role in glucose homeostasis by releasing glucose in the fasting state and by taking up and converting into glycogen part of the glucose absorbed from the gastrointestinal tract after meal ingestion. METHODS: To determine whether the hepatic denervation that accompanies liver transplantation interferes with these functions, we assessed glucose tolerance to an oral glucose load in seven patients at 2-6 weeks after orthotopic liver transplantation, in six patients after kidney transplantation, and in six healthy controls. Hepatic glycogen synthesis was non-invasively assessed over the 4 hours after ingestion of a glucose load by monitoring hepatic uridine diphosphoglucose turnover with 13C galactose and acetaminophen. RESULTS: Liver and kidney transplant recipients had increased postprandial glucose concentrations but normal hepatic uridine diphosphoglucose turnover, indicating an unaltered hepatic glycogen synthesis. CONCLUSIONS: These results indicate that denervated liver transplants have an adequate glucoregulatory function. Postprandial hyperglycemia in liver transplant recipients is therefore not due to alterations of liver glucose metabolism.

Mechanisms of postprandial hyperglycemia in liver transplant recipients: comparison of liver transplant patients with kidney transplant patients and healthy controls.

Impaired glucose tolerance or diabetes mellitus are frequent complications after organ transplantation, and are usually attributed to glucocorticoid and immunosuppressive treatments. Liver transplantation results in total hepatic denervation which may also affect glucoregulation. We therefore evaluated postprandial glucose metabolism in a group of patients with liver cirrhosis before and after orthotopic liver transplantation. Seven patients with liver cirrhosis of various etiologies, 6 patients having received a kidney transplant, and 6 healthy subjects were studied. Their glucose metabolism was evaluated in the basal state and over 4 hours after ingestion of a glucose load with 6.6 (2) H glucose dilution analysis. The patients with liver cirrhosis were studied before, and again 4 weeks (range 2-6) and 38 weeks (range 20-76, n=6) after orthotopic liver transplantation. Basal glucose metabolism was similar in liver and kidney transplant recipients. Impaired glucose tolerance was present in both groups, but postprandial hyperglycemia was exaggerated and lasted longer in liver transplant patients. Postprandial insulinemia was lower in liver transplant recipients, while C-peptide concentrations were comparable to those of kidney transplant recipients, indicating increased insulin clearance. Glucose turnover was not altered in both groups of patients during the initial 3 hours after glucose ingestion, but was higher in liver transplant early after transplantation during the fourth hour. Postprandial hyperglycemia remained unchanged in liver transplant recipients 38 weeks after liver transplantation, despite substantial reduction of immunosuppressive and glucocorticoid doses. We conclude that liver transplant recipients have severe postprandial hyperglycemia which can be attributed to insulinopenia (secondary, at least in part, to increased insulin clearance) and a late increased glucose turnover. These changes may be secondary to hepatic denervation.

Biocompatibility aspects of chronic hemodialysis and their clinical relevance.

Even if the definition of the term biocompatibility is still not clear, many of its manifestations during hemodialysis are now well documented. Some of their pathophysiological and clinical implications are briefly reviewed. It appears that not only the dialyzer membrane but also the extracorporeal circuit as a whole should be considered. Biological and clinical evidences confirm that the present more biocompatible membranes seem associated with better acute and long-term tolerance of hemodialysis when compared to less biocompatible membranes. However, potential side-effects such as backfiltration or drug interactions should not be overlooked.

Quantitation of proteinuria in kidney transplant patients: accuracy of the urinary protein/creatinine ratio.

The follow-up of renal function in kidney transplant patients requires sensitive and specific parameters which allow the detection of clinically significant changes. In this prospective study, we have evaluated the accuracy of the urinary protein/creatinine ratio (UP/UCreat), determined in morning urine specimens, in assessing 24-hour proteinuria (P24). Fivehundred and twenty paired samples were provided by 133 kidney transplant patients. The correlation coefficient of the linear regression was 0.93 in both in the first set of paired samples (133 samples) and in all paired samples (520 samples). In complete urine collections, the UP/UCreat predicted the level of proteinuria with both a good specificity (95 to 99%) and sensitivity (97 to 99%) at different levels of 24-hour protein excretion. The intraindividual coefficients of variation of P24 and UP/UCreat were evaluated in 82 patients (442 samples) and were 23% and 29% respectively. These results confirm that the UP/UCreat ratio in morning samples is a reliable estimate of the 24-hour proteinuria in kidney transplant patients. Additionally, its variation appears to accurately reflect changes in the rate of protein excretion.

Carpal tunnel syndrome: a frequent, invalidating, long-term complication of chronic hemodialysis.

Among 100 patients treated by chronic hemodialysis, 12 developed a carpal tunnel syndrome (CTS). After surgery, improvement was dramatic with regression of pain and paresthesiae within a few hours. Recovery of motor and sensory deficits was longer (2-3 weeks). No relationship could be established between CTS and the type of nephropathy, severity of polyneuritis, Ca and PO4 metabolism, the presence of vascular access and efficacy of dialysis. The bilaterality of the lesions in 7 patients suggests general pathogenic mechanisms superimposed to the presence of the vascular access. While only 3 out of 65 patients treated for less than 4 years complained about CTS, 9 out of 35 treated for more than 4 years were symptomatic.

Biocompatibility aspects of dialyzer reprocessing: a comparison of 3 re-use methods and 3 membranes.

While formalin reprocessing of cuprophan dialyzer membranes is known to improve their biocompatibility, the effects of different re-use methods have not been systematically investigated on different membranes. Therefore, the effects of reprocessing with formalin, hypochlorite-formalin and peracetic acid were successively investigated in 3 groups of 4 patients dialyzed on cuprophan (CU), cellulose acetate (CA) or polysulfone (PS). Leukocyte count, thrombocyte count and complement activation were studied during second and third use of the dialyzer. Formalin 3% storage was found to improve leukopenia, thrombocyte count and complement activation on CU but not on PS or CA where leukocyte and thrombocyte count worsened. Hypochlorite 1% rinsing prior to formalin 3% storage abolished the improvements observed on CU with formalin and induced on CA and PS the same leukopenia as formalin. In contrast, peracetic acid storage improved leukopenia, complement activation and thrombocyte count on the 3 membranes. In addition, it was found that storage of plasma-treated membrane fragments with peracetic acid abolished neutrophil oxygen radical production. Thus it appears that re-used membranes may not be systematically assumed to be more biocompatible, this property varying with both the type of membrane and the reprocessing technique.

Dialyzed polymorphonuclear neutrophil oxidative metabolism during dialysis: a comparative study with 5 new and reused membranes.

Dialyzed neutrophils were isolated at time 0, 5, 15 and 60 min after the onset of hemodialysis in patients successively treated on 5 new and reused membranes, that is cuprophan (CU), cellulose acetate (CA), polysulfone (PS), polycarbonate (PC) and polyacrilonitrile (PAN). Production of oxygen radicals was monitored by luminol and lucigenin-enhanced chemiluminescence (CL). During dialysis with CU and PC, cells remaining in circulation at the maximum neutropenia showed a significant decrease of luminol-enhanced CL, whether stimulated with opsonized zymosan or phorbol myristate acetate. This defect was transient and the responses normalized at 60 min or upon reuse of the membranes. Among the other membranes tested, only cells collected during the first use of PS showed an impaired CL response to phorbol myristate acetate, but not to opsonized zymosan. CL again normalized upon reuse. At 5 min of dialysis with each membrane, a plasma factor appeared that was able to stimulate oxygen radical production by autologous dialyzed and control cells. A dissociation between the oxidative responses of dialyzed neutrophils and neutropenia was observed depending on the nature of the membranes, suggesting that neutropenia is a multifactorial process in which oxygen radical production appears as an early disturbance.

Glomerulonephritis associated with Hemophilus aphrophilus endocarditis.

A 65 year old man developed endocarditis and septicemia due to Hemophilus aphrophilus, a Gram-negative coccobacillus. Renal rather than cardiac failure was the principal feature of his illness and renal biopsy was compatible with glomerulonephritis secondary to septicemia. Rapid recovery of renal function and improvement of the glomerular lesion followed antibiotic treatment of the septicemia. This case illustrates the renal damage that can occur in association with septicemia due to rarer infectious agents. As with more common organisms, specific antimicrobial therapy leads to rapid improvement of the nephropathy.

Uncontrollable hypertension in patients on hemodialysis: long-term treatment with captopril and salt subtraction.

It has been suggested that an inappropriate relationship between renin and exchangeable sodium is responsible for the hypertension of patients with chronic renal failure. Long-term blockade of the renin system by captopril made it possible to test this hypothesis in 8 patients on maintenance hemodialysis. Captopril was administered orally in 2 daily doses of 25 to 200 mg. Previously, blood pressure averaged 179/105 +/- 6/3 (mean +/- SEM) pre- and 182/103 +/- 7/3 mm HG post-dialysis, despite intensive ultrafiltration and conventional antihypertensive therapy. The 4 patients with the highest plasma renin activity normalized their blood pressure with captopril alone, whereas in the 4 remaining patients, captopril therapy was complemented by salt subtraction which consisted in replacement of 1-2 liters of ultrafiltrate by an equal volume of 5% dextrose until blood pressure was controlled. After an average treatment period of 5 months, blood pressure of all 8 patients was reduced to 134/76 +/- 7/5 mm Hg (P less than 0.001) pre- and 144/81 +/- 9/5 mm Hg (P less than 0.001) post-dialysis without a significant change in body weight. The present data suggest that captopril alone or combined with salt subtraction normalizes blood pressure of patients on chronic hemodialysis with so called uncontrollable hypertension.

Response of plasma vasopressin to changes in extracellular volume and/or plasma osmolality in patients on maintenance hemodialysis.

The effect of changes in extracellular volume versus changes in plasma osmolality on arginine vasopressin (AVP) release was studied in 6 patients with terminal renal failure maintained on chronic hemodialysis. The day of the study, the patients were treated by sequential ultrafiltration lasting 1 hour followed by a 3-hour conventional hemodialysis session. The ultrafiltration resulted in the removal of 460 to 1,170 ml (mean = 860 ml) of volume. Body weight during the combined procedures fell by 1.6 +/- 0.4 kg (mean +/- s.e.m.) while mean arterial pressure decreased only slightly. Plasma osmolality was unaffected by sequential ultrafiltration, but decreased from 313 +/- 4 mosm/kg H2O to 291 +/- 4 mosm/kg H2O during hemodialysis. Initial plasma AVP concentration was high at 4.45 +/- 0.25 pg/ml and remained unchanged during the sequential ultrafiltration at 4.55 +/- 0.37 pg/ml, but it fell during the hemodialysis to 2.47 +/- 0.45 pg/ml. A hypotensive episode observed in one patient towards the end of hemodialysis resulted in a sharp increase in plasma AVP concentration from 5.5 to 18 pg/ml. During the combined procedures, plasma AVP and plasma osmolality showed a close and linear correlation (r = 0.63, n = 23, p less than 0.001). These findings suggest that in patients on maintenance hemodialysis, changes in plasma osmolality play a predominant role in determining AVP secretion whereas a marked decrease in volume without ensuing hypotension has no effect on AVP release.

Is there a place for duplex screening of brachial artery in haemodialysis patients with vascular access?

BACKGROUND: Vascular access (VA) stenosis with subsequent thrombosis remains one of the major causes of morbidity and hospitalization in haemodialysis patients. The present cross-sectional study was planned in order to analyze the usefulness of brachial artery duplex ultrasound for detection and prediction of vascular access stenoses. METHODS: Color duplex ultrasound (Apogée Cx200, sectorial probe 7.5 MHz) was used to obtain the anatomical pattern of the VA and flow velocity waveforms of the brachial artery in 77 non-selected VA (47 Ciminio-Brescia fistulae and 30 PTFE grafts). In each VA, the resistance index (RI), the mean blood flow rate (Q) and the blood flow ratio index (QI) (QI = VA flow rate/contralateral flow rate) were calculated at the level of the brachial artery. The sensitivity and specificity of these brachial Doppler parameters were calculated for the detection of VA stenosis. In normal VA, positive (PPV) and negative predictive (NPV) values were calculated for the development of clinical stenotic complications 3 months post ultrasound examination. RESULTS: Thirteen of the 77 VA (17%) were identified as stenosed by duplex ultrasound and confirmed by fistulography and/or during surgical exploration. The best screening tests for VA stenosis detection were a QI threshold < 4.0 with a sensitivity and specificity of 69 and 69% and an RI > 0.55 with a sensitivity and specificity of 62 and 66%, respectively. In the VA considered as normal by ultrasound, the prediction of subsequent stenosis within three months post-ultrasound examination gave a PPV of only 18% and 19% for RI and QI, respectively. NPV for RI and QI were 90% and 88%. CONCLUSIONS: While Doppler ultrasound is a useful non-invasive test for the detection of prevalent VA stenosis, our results do not confirm that abnormal brachial Doppler flow parameters can predict short term development of VA stenosis.

[Laparoscopic nephrectomy in the liver donor: introduction of the method and preliminary results]. / Néphrectomie par laparoscopie chez le donneur vivant: introduction de la méthode et résultats préliminaires.

INTRODUCTION: The shortage of organs available for renal transplantation has focussed attention on the use of live donors. Techniques for laparoscopic nephrectomy have recently been described, which have limited morbidity, duration of hospitalization and the period off work. However, these surgical procedures are difficult, and may be risky for the organ to be transplanted. METHOD: The laparoscopic live donor nephrectomy was introduced in stages, including the use of a videoconference from a reference center. In this article, the prospective analysis of the present authors' preliminary results has been presented. RESULTS: Ten kidneys were removed by laparoscopy, i.e., three from the left and seven from the right side. No conversion of this technique to laparotomy was necessary. The mean warm ischemic time was five minutes, and in the last six operations it did not exceed three minutes. The patients were able to leave hospital between four and eight days following surgery. After a mean follow-up of 10.5 months, organ survival was 100%, and in all grafts excellent function was observed. CONCLUSION: The quality of these preliminary results which may act as a reference and the careful introduction of a live donor laparoscopic program could provide an incentive to potential donors, and thereby increase the pool of organs available for transplantation.

[Herpetic esophagitis following renal transplantation]. / Oesophagite herpétique après transplantation rénale.

We report the case of a patient who developed herpes simplex oesophagitis less than one month after renal transplantation. Graft rejection treatment may have induced this infection. Diagnosis was suspected at endoscopy and was confirmed by biopsy. The patient was cured by intravenous acyclovir and temporary discontinuation of immunosuppressive medication.