[Prosthetic valve endocarditis due to Coxiella burnetii: six cases]. / Endocardites à Coxiella burnetii sur prothèse: six observations.

PURPOSE: Prosthetic valve endocarditis is a dangerous complication of valvular surgery (3-6%). Among involved pathogens, Coxiella burnetii is an occasional agent, though isolated with increasing frequency. We report our experience with this peculiar endocarditis and lay stress on specific diagnostic and therapeutic difficulties. METHODS: Between 1990 and 1995, six patients retrospectively met the diagnosis criteria for definite endocarditis due to Coxiella burnetii. RESULTS: Five Algerian men and one French woman presented with prosthetic valve endocarditis with negative blood cultures (on bioprosthesis: four cases, on mechanical valve: two cases). The main clinical and biological feature was febrile congestive heart failure with hepatomegaly, splenomegaly, hepatic and renal abnormalities, inflammatory syndrome, hypergammaglobulinemia, anemia and lymphopenia. Serological testing for Coxiella burnetii provided diagnosis in all cases. Echocardiography displayed vegetations in all cases. Valvular replacement was performed in four patients. With antibiotic therapy including doxycycline or/and hydroxychloroquine, quinolones or rifampicine, all patients experienced complete clinical, biological and echographic remission. CONCLUSION: Q fever prosthetic valve endocarditis presents as a systemic disorder occurring in patients with valvular heart disease. From now on, early diagnosis and efficient medical treatment may provide permanent prosthetic sterilization.

Total ureteral replacement by subcutaneous pyelovesical bypass in ureteral necrosis after renal transplantation.

OBJECTIVES: Ureteral necrosis is a rare complication of renal transplantation, and is seldom cured by endoscopic management alone. To avoid the potential hazard to the graft created by an open ureteral reconstruction in cases of renal transplant ureteral necrosis, we have appiled a new minimally invasive technique of total ureteral replacement, initially described for the palliative treatment of ureteral obstructions. The subcutaneous bypass technique is based on the use of a silicone-PTFE-bonded tube tunnelled underneath the skin. METHODS: Total ureteral replacement by subcutaneous pyelovesical bypass was performed in three renal transplant patients (two men and one woman; mean age 41 years, (range 23-58) years with ureteral necrosis after failure of primary endoscopic treatment. The ureteral lesion was distal necrosis in two patients, and a total necrosis in the other. Under general anaesthesia and fluoroscopic guidance, a percutaneous tract was created and progressively dilated. The ureteral prosthesis was introduced into the pyelocaliceal cavities through a 30 F Amplatz sheet, then subcutaneously tracked down to the suprapubic area, and introduced into the bladder via a short incision. RESULTS: There was no operative or postoperative morbidity. There was no obstruction, dislodgement or encrustation of the prosthesis. There were no bladder-related symptoms, or clinical reflux, and no abdominal wall complications. An asymptomatic episode of lower urinary tract infection (Staphylococcus epidermidis) was observed in the female patient. All the grafts were functioning with fine pyelocaliceal cavities, with a mean follow-up of 32 months (13-69 months). CONCLUSION: Total ureteral replacement by subcutaneous pyelovesical bypass is a simple and safe technique of ureteral reconstruction in renal transplantation. Late encrustation of the prosthesis may occur, and the prosthesis may need to be changed in such cases. Subcutaneous pyelovesical bypass can be regarded as an alternative to an open procedure to treat ureteral necrosis after renal transplantation.

[Cooling shell in renal transplantation. Thermometric evaluation of a prototype]. / Coque réfrigérante en transplantation rénale. Evaluation thermométrique d'un prototype.

We have developed a cooling system for renal transplants designed to eliminate the second period of warm ischaemia corresponding to the vascular anastomosis phase of renal transplantation. This is an autonomous and independent system which forms a shell around the transplant. Following application of the system, cooling is achieved by refrigeration of a Multitherm sponge contained in the wall of the shell. The thermometric characteristics of a prototype were evaluated in vitro and in vivo in pigs. This system allows the kidney to be preserved at a temperature of less than 10 degrees C for 1 hour without inducing any risk of lesions of the renal surface. Human applications should be developed in the near future.

[Occurrence of extracapillary glomerulonephritis during Mediterranean boutonneuse fever]. / Survenue d'une glomérulonéphrite extracapillaire au cours d'une fièvre boutonneuse méditerranéenne.

Boutonneuse spotted fever is a summer and late spring infection caused by Rickettsia Conorii mainly in Middle East countries adjacent to the mediterranean coast (1). Malignant forms have been described in debilitated patients associated with prerenal azotemia, acute tubular necrosis or renal vasculitis (2, 3). We report for the first time to our knowledge, the association of an extracapillary glomerulonephritis with a Boutonneuse spotted fever. This observation suggest that Rickettsia Conorii, as other bacteria, could participate to the development of glomerulonephritis.

Renal hemodynamic and functional effect of PEEP ventilation in human renal transplantations.

Increased intrathoracic pressure with positive pressure breathing (PPB) induces renal hypoperfusion and excretion function impairment the mechanism of which may be partially related to reflex sympathetic nerve activation. The consequences of renal denervation on PPB-induced renal impairment are unknown. This study was conducted to evaluate the effects of increasing intrathoracic pressure with positive end-expiratory pressure (PEEP) on renal blood flow (RBF, pulsed Doppler implantable microprobes) and function in 12 kidney transplantation recipients during the immediate post-transplantation period. Three sets of measurements were performed during successively zero end-expiratory pressure (ZEEP), 15 cm H2O PEEP, and back to ZEEP. PEEP ventilation was associated with mean arterial pressure (MAP) and cardiac output (CO) decrease (-12%, p < 0.01; -26%, p < 0.01, respectively). RBF remained constant in the three protocol conditions. PEEP ventilation was associated with a decrease in urinary output (8.5 +/- 5.6 versus 12.9 +/- 8.6 ml/min; p < 0.01), urinary sodium concentration (115 +/- 14 versus 121 +/- 12 mmol/L; p < 0.01) sodium excretion rate (1 +/- 0.7 versus 1.6 +/- 1.1 mmol/min; p < 0.01), and creatinine clearance (17.1 +/- 10 versus 23.2 +/- 13.6 ml/min; p < 0.01). PEEP-induced urinary output decrease was correlated to renal perfusion pressure decrease (r = 0.7, p = 0.016). These results suggest that despite denervation and renal blood flow stability, renal handling of water and salt is perfusion pressure-dependent during PEEP in human renal allograft recipients.

Hypertensive encephalopathy after bilateral carotid endarterectomy.

BACKGROUND: Hypertension occurs frequently after carotid endarterectomy and may lead to cerebral vascular complications and myocardial infarction. Its pathophysiology has recently been related to surgically induced damage of carotid baroreceptors. CASE DESCRIPTION: A 45-year-old normotensive man with no history of epilepsy was admitted 3 weeks after bilateral carotid endarterectomy for severe repetitive paroxysmal headaches, vomiting, and agitation that were closely associated with attacks of marked hypertension. During one of these attacks, he had a grand mal seizure. Plasma catecholamine levels during hypertensive attacks were highly elevated despite the absence of pheochromocytoma, reflecting abnormalities in baroreceptor sensitivity that lead to unrestrained activation of the central sympathetic nervous system. Heart rate response to Valsalva maneuver showed suppression of the usual tachycardia, indicating baroreceptor reflex insensitivity. CONCLUSIONS: We report the first case of hypertensive encephalopathy associated with baroreflex failure syndrome after bilateral carotid endarterectomy. The role of blood pressure monitoring may be critical in revealing carotid baroreceptor insensitivity in such clinical settings.

Proton nuclear magnetic resonance spectroscopy of urine and plasma in renal transplantation follow-up.

Urine and plasma samples from 39 patients who underwent renal transplantation were analyzed by proton nuclear magnetic resonance (NMR) spectroscopy. The most relevant resonances for evaluating renal function after transplantation were those arising from citrate, trimethylamine-N-oxide (TMAO), alanine, and lactate when compared to creatinine. A resonance at 3.7 ppm was related to cyclosporine toxicity when associated with elevated levels of TMAO. The respective variations in these metabolites in urine could contribute to prognosis and diagnosis of renal function impairment related to cyclosporine toxicity or overdosage, or to rejection. Thus, NMR spectroscopy should improve the follow-up and management of renal transplantation patients.

Renal disease associated with HIV infection: a multicentric study of 60 patients from Paris hospitals.

Sixty HIV-infected patients presenting renal symptoms who underwent percutaneous renal biopsies were analysed. According to the CDC classification, 44 patients were staged in group IV, five in group III, and 11 in group II. Patients were divided in two groups according to their ethnic origin (29 black patients and 31 white patients). Risk factors such as homosexuality, multiple transfusions or intravenous drug abuse (IVDA) were identified in all white patients except two, but in only nine (31%) of the black patients. Three main patterns of renal disease were observed: focal and segmental glomerulosclerosis (FSGS) was found predominantly in black patients (23 black patients versus 3 Caucasians, P < 0.001) and was associated with the nephrotic syndrome; immune-complex-type glomerulonephritis (ICGN) was frequent in black and white patients (21% and 52% respectively) including four cases of IgA nephritis all seen in white patients; and 10 cases of lupus-like nephritis (4 black and 6 white patients). The frequent hypergammaglobulinaemia in those patients suggests a pathogenic role of polyclonal B cell activation in ICGN. Interstitial nephritis was present in 48 and 52% of the black and white patients respectively and did not seem related to drug toxicity or superimposed infectious disease. In addition to interstitial nephritis, the coexistence of multivisceral lymphocytic infiltration involving accessory salivary glands, liver and/or lung, found in six patients possibly suggests a virus-induced immune disorder.

Sulfadiazine-induced crystalluria in AIDS patients with toxoplasma encephalitis.

Toxoplasma encephalitis is the most common opportunistic infection of the central nervous system in patients with AIDS. The treatment of choice is a combination of sulfadiazine and pyrimethamine. We present here four patients with AIDS treated for toxoplasmic encephalitis who developed sulfadiazine-induced crystalluria. This complication was rapidly reversible with rehydration and urine alkalinization. Patients with AIDS treated with high doses of sulfadiazine should be adequately hydrated, and their urinary pH maintained above 7.5 to prevent sulfadiazine-induced crystalluria.

[Hypercalcemia in blood diseases and cancers]. / Hypercalcémies des hémopathies et des cancers.

The clinical classification of malignant hypercalcaemias according to the presence or absence of bone lesions no longer corresponds to the physiopathology of these hypercalcaemias as it is known today. Both focal osteolysis and humoral hypercalcaemia involve a number of substances, such as prostaglandins, cytokines, growth factors, PTH-rp and calcitriol, the action of which is neither specific nor single. A knowledge of their role in the pathogenesis of hypercalcaemia should lead to the development of antagonists for therapeutic purpose and to a better understanding of their individual physiological effects, since some of these mediators are present in non-tumoral tissues. In humoral hypercalcaemia, PTH-rp seems to play a major role on kidneys and bones.