Evaluation of Discomfort in Nasopharyngeal Swab Specimen Collection for SARS-CoV-2 Diagnosis.

BACKGROUND: The rapid spread of COVID-19 worldwide has impo-sed the need to identify a test that quickly recognizes affected subjects, both symptomatic and asymptomatic. The most reliable option has been proven to be the RT-PCR, which allows to detect virus RNA on a specimen from a high viral load site, such as nasopharynx. Nasopha-ryngeal sample collection is possible by means of a nasopharyngeal swab (NPS) and is a practical and relatively non-invasive technique, but rather bothersome for the recipient. AIM: The aim of the present study is to evaluate the discomfort evoked during NPS. MATERIALS AND METHODS: We surveyed 429 patients receiving NPS before hospitalization or other procedures non related to COVID-19. For each one we noted the discomfort level felt during the swab using a 11-point numeric rating scale (NRS) for pain and the total time needed for the procedure to be taken. Sex, age, smoking status and positive history of previous swab have been taken into account. RESULTS: We found that, among the variables, sex had a statistically significant impact on the perceived discomfort of nasal swab, with females experiencing slightly more discomfort. CONCLUSIONS: NPS is largely a none-to-minimum discomfort in-ducing procedure. The differences in perceived discomfort could be explained based on anatomical features, and should remark the need for a tailored and anatomy-oriented approach in each patient.

Pharmacological, Surgical and Diagnostic Innovations in Meniere's Disease: A Review.

PURPOSE: To investigate literature about pharmacological, surgical, and diagnostic innovations for Meniere's Disease (MD). SUMMARY: Meniere's disease is an inner ear disorder characterized by the presence of endolymphatic hydrops in the inner ear and symptomatology of recurrent and debilitating vertigo attacks, tinnitus, aural fullness, and fluctuating sensorineural hearing loss. Although many therapeutic options for MD have been proposed during years, no consensus has been reached by the scientific community. In the last decade, many therapeutic options have been proposed, as intratympanic steroid, intratympanic gentamicin, and intravenous glycerol. Recently, the role of the antisecretory factor in the diet of MD patients have been investigated. Surgery is recommended for intractable MD; some authors proposed new approaches including transcanal endoscopic infracochlear vestibular neurectomy, new marsupiliazation technique in sac surgery, and tenotomy of the stapedius and tensor tympani muscles.

Calcineurin inhibitor reduction based on maintenance immunosuppression with mycophenolate mofetil in renal transplant patients: POP study.

Since calcineurin inhibitors (CNI) have been introduced, they have become the cornerstone of immunosuppression for renal transplant patients, but their cardiovascular and neurological toxicities, and primarily their renal toxicity, have brought about an increased effort to find combinations of immunosuppressants that are either CNI-free or that use minimum doses of these drugs. The weight of immunosuppression therefore lies with drugs that have a better toxicity profile. The POP observational transverse study including 213 renal transplant patients was designed to study CNI minimization strategies. The mean time of transplant evolution to the time of reduction was 9.9 +/- 11.8 months. The acute rejection rate to the start of reduction was 9.4%. Almost all the patients were undergoing treatment with CNI + mycophenolate mofetil (MMF) + steroids in the immediate posttransplantation period. When reduction was chosen, all patients were undergoing treatment with MMF (mean dose at the start of reduction = 1490.7 +/- 478.0 mg/d). Among the cohort, 66.7% of patients were being treated with tacrolimus (mean C0 levels 13.3 +/- 6.6 ng/mL) and 33.3% with cyclosporine (mean C0 levels 192.2 +/- 94.0 ng/mL; mean C2 levels 1097.5 +/- 457.6). The main reasons for withdrawal were nephrotoxicity (55.9% of the cases), as well as prevention of adverse effects (21.6%). The mean target CNI dose reduction was 41.4% +/- 21.45% in the tacrolimus group and 28.6 +/- 10.0% in the cyclosporine group. In conclusion, CNI toxicity, primarily renal toxicity, makes reduction of these drugs based on the use of full MMF doses an alternative to manage renal transplant patients.

Gastrointestinal complications in renal transplant recipients: MITOS study.

INTRODUCTION AND METHODS: An epidemiologic multicenter study was performed to evaluate the prevalence and management of gastrointestinal (GI) complications in solid organ transplant patients. A total of 1788 recipients were included, 1132 of which corresponded to renal transplanted patients. RESULTS: The mean age for the renal transplanted patients was 52 +/- 13.2 years. The mean time from the transplantation was 5.4 +/- 5.4 years. 17.7% showed some pretransplant GI disease, while 53% presented this type of complication in the posttransplant period. Diarrhea was the most prevalent GI complication (51.5%) and digestive perforation was the GI disorder that affected the patients daily living the most. From the patients with GI complications, 71% received pharmacological treatment, using gastric protectors in 91.3% of the cases. Regarding immunosuppressive drugs, in 30.9% of the cases the dose of the drug was reduced, in 9.3% discontinued temporarily and in 7.5% discontinued permanently. These changes mainly affected the MMF (89%, 83% and 74% for dose change, temporary and permanent discontinuation, respectively). CONCLUSIONS: The prevalence of GI complications in renal transplant exceeded 50%, and affected patients' daily living. The management of these complications was based on treatment with gastric protectors, dose reduction and/or partial or definitive MMF discontinuation.

Subclavian vascular access stenosis in dialysis patients: natural history and risk factors.

Stenosis of the subclavian vein (SVS) after cannulation occurs in 15 to 50% of chronic hemodialysis patients, and impedes the placement of an arteriovenous fistula in the ipsilateral arm. Its natural history and pathogenic mechanisms are not well established. This study examined 42 consecutive chronic renal failure patients (28 men and 14 women; 46+/-19 yr) in whom subclavian catheters had been placed as the initial vascular access for hemodialysis. All patients underwent sequential venography studies: at baseline (24 to 48 h after removal of the catheter) and 1, 3, and 6 mo thereafter. Venograms were considered abnormal when there was evidence of unequivocal strictures (more than 30% narrowing), with or without collateral circulation. At baseline, 52.4% (n=22) of patients showed stenotic vein lesions (n=19) or total thrombosis (n=3), and identical lesions were also observed after 1 mo. Surprisingly, 10 of 22 patients with initial SVS (45.4%) showed spontaneous recanalization of venous lesions in the venographies performed 3 mo after removal. The patients with normal baseline venograms (n=20) showed no change during follow-up. Patients with definitive stenosis at 6 mo (n=12) had a higher number of inserted catheters (1.58+/-0.6 versus 1.2+/-0.48; P < 0.05), longer time in place (49.08+/-32.2 versus 29.03+/-26.6 d; P < 0.05), and higher number of dialysis sessions (21+/-13.8 versus 12.4+/-11.4; P < 0.05) than those without SVS or with spontaneous recanalization of venous lesions during follow-up. Furthermore, a higher number of catheter-related infections were observed in patients with definitive SVS (66.6% versus 33.3%; P < 0.05). In summary, SVS is observed in more than half of patients 24 to 48 h after catheter removal and 1 mo later. Even when recanalization occurs in many cases, a definitive stenosis is seen in 28% of patients by the third month. Thus, the creation of an ipsilateral vascular access is possible provided that venography is normal at this time. Finally, mechanical factors and catheter-related infections are the major risk factors for the development of late SVS.

Is it possible to control hyperphosphataemia with diet, without inducing protein malnutrition?

Dietary intervention, phosphate (P) removal during dialysis and, especially, phosphate binders are current methods for the management of hyperphosphataemia. Ideally, the amount of P absorbed from the diet should equal the amount of P removed during dialysis, and this must occur in the context of an adequate protein intake. We evaluated the relationship between P intake and protein intake in 60 stable chronic uraemic patients (mean age 55+/-15 years, 25% diabetics, 68% males) on standard 4 h haemodialysis. The dietary counselling was relatively free for protein and calories. Nutrient intake was recorded during a 5 day period, and average daily ingestion of P and proteins was calculated using a computerized diet analysis system. A highly significant correlation was observed between protein and P intake. The mean daily ingestion of P and proteins was 998+/-316 mg and 64+/-19 g (1+/-0.4 g/kg/day), respectively. For an optimal protein diet of 1-1.2 g/kg/day, the P intake was 778-1444 mg. The amount of P removed by haemodialysis, extrapolated to an average week, is 250-300 mg/day. Since approximately 40% of P ingested is absorbed from the gut by uraemic patients treated with intestinal P binders, 750 mg of P intake should be the critical value above which a positive balance of P may occur. This value corresponds to a protein intake of 45-50 g per day (>0.8 g/kg body weight/day for a 60 kg patient). In patients undergoing standard chronic haemodialysis, a neutral P balance is difficult to achieve, despite phosphate binder therapy, when protein intake is >50 g. Additional protein restriction, in order to obtain a neutral balance, may impose the risk of protein malnutrition.

Parathyroid function in long-term renal transplant patients: importance of pre-transplant PTH concentrations.

Lack of resolution of hyperparathyroidism after long-term renal transplantation is common. The relative roles of the graft function attained and the degree of pre-transplant hyperparathyroidism have not been established. Intact parathyroid hormone (iPTH) and several clinical parameters were studied before and 68.6+/-26.8 months (range: 30-124) after renal transplantation in 62 patients (20 females/42 males) with good renal function (creatinine <2 mg/dl). iPTH decreased from 214+/-229 pre-transplantation to 116+/-70 pg/ml post-transplantation (P<0.01). However, only 22.6% of patients had PTH concentrations in the normal range, and values greater than twice the upper normal limit were not uncommon (27.4%). Of the many variables analysed, creatinine (r=0.43; P=0.001) and pre-transplant PTH (r=0.31; P=0.02) significantly correlated with post-transplant PTH. After selecting patients with serum creatinine <1.5 mg/dl (n=46), pre-transplant PTH emerged as the more important predictor of post-transplant PTH (r=0.58; P<0.0001). After controlling for creatinine, the partial correlation was r=0.53, P<0.0001. We concluded that spontaneous resolution of hyperparathyroidism after renal transplantation is uncommon. In addition, the magnitude of pre-transplant hyperparathyroidism and the renal function determine the long-term post-transplant parathyroid function.

Prediction of left ventricular mass changes after renal transplantation by polymorphism of the angiotensin-converting-enzyme gene.

Cardiac complications are the main cause of death in renal transplant patients and left ventricular hypertrophy (LVH) may play a determinant role. An association between the insertion-deletion polymorphism of the angiotensin-converting enzyme (ACE) gene and LVH has been reported in adults. However, little is known about the genetic influence on left ventricular mass changes after renal transplantation, where unique environmental factors, such as cyclosporine A (CsA) and prednisone treatment concur. In fact, CsA treatment has recently been associated with the development of LVH. We prospectively determined the changes on cardiac structure and function, assessed by echocardiographic criteria, in 38 consecutive nondiabetic adults who received a cadaveric renal allograft. They were treated with cyclosporine and prednisone and maintained a good renal function during the follow-up. Echocardiographic studies (M-mode, 2-B and color flow Doppler) were performed without previous knowledge of the genetic typing, at the time of transplantation, and 6 and 12 months later. ACE alleles were typed using a PCR-based assay developed to ascertain the presence of an insertion (I)-deletion (D) polymorphism in intron 16 of the ACE gene. Patients with the so-called "unfavorable" DD genotype (N = 16) were compared with the ID or II genotypes (N = 22). The baseline left ventricular mass index was similar in patients with or without the unfavorable DD genotype (X +/- SE; 166.6 +/- 10.4 vs. 181.3 +/- 9 g/m2, respectively) and a similar proportion fulfilled the criteria of LVH (88% vs. 82%, respectively). The mean percent increase of the left ventricular mass index 12 months after renal transplantation was significantly higher in patients with the DD genotype compared to those with other genotypes (21.3 +/- 7.9 vs. -0.08 +/- 4.9%, respectively; P < 0.05). As a result, 94% of DD patients showed LVH at the end of the follow-up, while 68% of the ID or II patients had LVH (P < 0.05). In addition, the left ventricular ejection fraction significantly increased only in ID or II patients 12 months after transplantation with respect to baseline (ID/II patients, 70.4 +/- 1.5 vs. 63.7 +/- 1.8%; P < 0.05; DD patients, 68.3 +/- 2.1 vs. 63.3 +/- 2.9%). The deleterious effect of the DD genotype was independent of blood pressure, biochemical parameters, weight gain, and cumulative steroids dosages or cyclosporine levels. In conclusion, genetic factors determine the changes on cardiac structure and function after renal transplantation. The presence of the DD genotype of the ACE gene is a marker associated with an elevated risk of LVH in this population.

Influence of vitamin D receptor genotype on bone mass changes after renal transplantation.

Renal transplant patients immunosuppressed with cyclosporine A (CsA) exhibit both a significant bone loss and an increased rate of bone fractures. An association between common allelic variants of the the vitamin D receptor (VDR) gene and bone mineral density and turnover has been reported in adults. However, the genetic influence on the rate of bone loss after renal transplantation has not been explored. We prospectively determined the changes in spinal mineral density in 34 consecutive nondiabetic adults who received a cadaveric renal allograft. Serum biochemical markers of bone metabolism and the vertebral mineral density (VMD) assessed by quantitative computed tomography were determined at the time of transplantation and three and twelve months later. In fifteen patients the histomorphometric features of iliac bone were analyzed at baseline and twelve months after transplantation. VDR alleles were typed by a PCR assay based on a polymorphic BsmI restriction site. Patients with the so-called "favorable" bb genotype (N = 12) were compared with those with the Bb or BB genotype (N = 22). Baseline VMD was similar in patients with or without the favorable bb genotype. Three months after transplantation the mean (+/- SD) VMD decreased 14 +/- 13.3 percent in all patients (16.5 +/- 13.1% in patients homozygous for the b allele and 13.77 +/- 13.9% in those with Bb or BB genotypes). The rate of VMD loss at this time inversely correlated with pretransplant PTH levels (r = -0.40; P < 0.05). Between 3 and 12 months after transplantation, patients with the favorable bb genotype recovered more VMD than those with Bb or BB types and showed a significantly higher Z score at the end of the follow-up (-0.37 +/- 1.16 vs. -1.10 +/- 1.20, respectively; P < 0.05). The beneficial effect of bb genotype was independent of the prevailing PTH levels and was also observed in those patients with a baseline PTH level < 250 pg/ml (final Z score: bb, -0.42 +/- 1.3, N = 11; Bb/BB, -1.35 +/- 0.8, N = 11, P < 0.05). At the end of follow-up, the histomorphometric studies showed a higher bone formation rate adjusted for PTH levels in patients with the Bb or BB genotype than in those with the favorable bb genotype (0.29 +/- 0.06 vs. 0.21 +/- 0.08 micron3/micron2/day respectively; P < 0.05). In conclusion, high pretransplant PTH levels enhance the early trabecular bone loss after renal transplantation, and functionally different alleles of the vitamin D receptor gene may condition the bone turnover and the degree of recovery of the bone mass.

Caloric rather than protein deficiency predominates in stable chronic haemodialysis patients.

BACKGROUND: The monitoring of energy and protein intake is considered fundamental in uraemic patients. However, in the clinical practice only protein ingestion is indirectly evaluated by the protein catabolic rate. METHODS: In a cross-sectional study we evaluated the relationship between caloric and protein intake of 29 stable chronic haemodialysis patients (18M, 11F, mean age 49 +/- 17 years, 68 +/- 6 months on maintenance haemodialysis), and the validity of protein catabolic rate determination. Normalized protein catabolic rate was obtained according to Sargent's formula, and Watson's equation was used to calculate urea distribution volume. Caloric and protein intake were recorded during a 3-day period, and average daily ingestion of nutrients was calculated using a computerized diet analysis system. RESULTS: A greater reduction of daily energy intake (26.8 +/- 11.9 Kcal/kg bw) than daily protein intake (1.02 +/- 0.4 g/kg bw) was observed. Fifty-nine percent of patients had low protein intake while 86% of patients had lower caloric intake than recommended. An inverse relationship between age and protein (r = -0.65, P < 0.001) or caloric intake (r = -0.67, P < 0.001) was observed. Negative relationships between daily protein (r = -0.60, P < 0.01) and also caloric intake (r = -0.39, P < 0.05) and the ratio between the urea generation rate and the total dietary nitrogen were found, indicating that in patients with low nutrient intake the nitrogen balance tends to be negative. Normalized protein catabolic rate was directly correlated with protein intake (r = 0.77, P < 0.001). A protein catabolic rate cut-off of 1 g/kg bw correctly identified all patients with normal daily protein intake, and 14 of 17 patients with deficient daily protein intake (< 1 g/kg bw). Thus in only 10% of haemodialysis patients an imbalance between both parameters was observed. Moreover, patients with a daily protein intake lower than 1 g/kg bw were older and showed lower BUN and protein catabolic rate values than their counterparts. CONCLUSIONS: Nutritional abnormalities are frequently found, even in apparently clinically stable patients on chronic haemodialysis. Caloric rather than protein undernutrition is the major abnormality of their wasting. Inadequate intake of proteins and calories appears more commonly in older patients, and in association with lower BUN and protein catabolic rate values. Although normalized protein catabolic rate shows a direct correlation with a daily protein intake, the identity line shows that when daily protein intake was lower than 1 g/kg bw, it was overestimated by protein catabolic rate. Conversely, when daily protein intake is higher than 1 g/kg bw it is underestimated by the protein catabolic rate. This relationship should to be considered when interpreting the protein catabolic rate in a clinical setting.

Bone disease in predialysis, hemodialysis, and CAPD patients: evidence of a better bone response to PTH.

The spectrum of bone disease in predialysis and dialysis patients has changed during the last decade. The incidence of aplastic bone disease has increased and this can not be attributed to bone aluminum deposition; moreover, low bone cellular activity is present despite a moderate elevation in PTH levels. This study compares PTH levels and types of bone disease in both predialysis and dialysis patients from the same geographical area. We prospectively studied 119 unselected end-stage renal disease patients: 38 were immediately predialysis (PreD), 49 on hemodialysis (HD), and 32 on CAPD. A bone biopsy was performed in all patients. Aplastic bone disease with < 5% bone surface aluminum was a common finding (48%, 32%, and 48%, in PreD, HD, and CAPD, respectively). In all groups, an intact PTH level below 120 pg/ml was highly predictive of low bone turnover. Conversely, a PTH level above 450 pg/ml was always associated with histologic features of hyperparathyroid bone disease. Among the bone histomorphometric parameters, osteoblast surface showed the best correlation with intact PTH in each group, and the slope of the regression line for this correlation was significantly steeper in HD and CAPD than PreD patients. Thus, the range of PTH (95% confidence limit bands) needed to obtain a normal osteoblast surface of 1.5% was greater in preD than in HD and CAPD patients (300 to 500 vs. 75 to 260 pg/ml, respectively). In all groups some degree of marrow fibrosis was observed when PTH levels were greater than 250 pg/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Adynamic bone disease with negative aluminium staining in predialysis patients: prevalence and evolution after maintenance dialysis.

Aplastic bone disease (ABD) is a common form of renal osteodystrophy and is characterized by a defect in bone matrix formation and mineralization without an increase in osteoid thickness. The prevalence and pathogenesis of ABD in predialysis patients is largely unknown. We prospectively studied 92 unselected predialysis patients with a creatinine clearance < 10 ml/min/1.73 m2 and a mean age of 45 +/- 2 years (61 M, 31 F). None of the study patients had received any form of vitamin D therapy, and CaCO3 was the primary phosphate binder. Aplastic bone disease was observed in 30 (32%) patients. Stainable bone aluminium surface was < 3% in all ABD patients. Patients with ABD were older (52 +/- 3 versus 42 +/- 2 years; P < 0.01) and had reduced serum intact PTH compared to non-ABD patients (199 +/- 25 versus 561 +/- 87 pg/ml; P < 0.001). Patients with diabetes mellitus showed lower PTH values (179 +/- 31 versus 432 +/- 62 pg/ml; P < 0.001) and a lower incidence of advanced hyperparathyroidism bone lesions (16% versus 46%; P < 0.05) than non-diabetic patients. However, diabetes was not clearly associated with low bone turnover disease (56% in diabetics versus 41% in non-diabetics; P = 0.1). A second bone biopsy was obtained in eleven ABD patients after a period of 16.6 +/- 2.2 months on maintenance dialysis with a dialysate calcium of 7 mg/dl. Bone histology was unchanged in 10 patients, and one evolved to mild hyperparathyroidism. Trabecular bone volume did not change (22.7 +/- 1.7 versus 20.7 +/- 1.7%), and the stainable bone aluminium surface remained < 3%.(ABSTRACT TRUNCATED AT 250 WORDS)

Ablation of irreversibly rejected renal allograft by embolization with absolute ethanol: a new clinical application.

Surgical allograft nephrectomy has been the conventional therapy for removing failed kidney allografts when clinical manifestations of graft intolerance appear. However, removal of a transplanted kidney is an extensive surgical procedure. On the other hand, transcatheter vascular embolization (TVE) has proven useful in ablating organs and could be applied to renal transplant ablation. The aim of this study was to present the results of TVE for the treatment of graft intolerance syndrome (GIS) in failed allograft kidneys. Transcatheter vascular embolization was performed in 14 allograft recipients (33 +/- 13 years of age; 10 men and four women) affected by GIS after irreversible kidney allograft failure. Graft intolerance syndrome was diagnosed by fever (93%), hematuria (50%), graft pain (36%), flu-like symptoms (29%), and increased graft size (29%). Absolute ethanol (0.1 mL/kg body weight) was injected in the allograft artery, and in seven patients a stainless steel coil was left in the renal artery following ethanol injection. All patients showed clinical disappearance of the GIS. No major complication occurred, although a postembolization syndrome of pain, fever, hematuria, numbness, and paresthesia of the affected area appeared in 11 of the 14 patients. After 2 to 56 months of follow-up no late complications occurred, with the exception of a graft abscess formation in one patient after 6 months of embolization. Subsequent transplantectomy was uneventful. In conclusion, TVE is a safe and effective method for kidney graft ablation, and it may become an alternative treatment for GIS following irreversible rejection.

Pulsatile-secretion of parathyroid hormone in patients with chronic renal failure.

Peripheral blood concentration of intact PTH is a simple assay very useful in the diagnosis and evolutive control of secondary hyperparathyroidism in patients with chronic renal failure. Episodic secretion of PTH in CRF patients would affect interpretation of single random determinations. To evaluate the secretory pattern of intact PTH we sampled peripheral blood at 6-min intervals for 60 to 90 min from seven normal subjects (group I) and seven patients with chronic renal failure (group II: 4 with normal parathyroid function and 3 with hyperparathyroidism). The resultant time series of serum intact PTH and ionized calcium were assessed by computerized cluster data analysis program. Evaluation of episodic intact PTH pulsatile nature revealed that in group I, 3 out of 7 normal subjects presented 1 maximum and 6 subjects presented at least one minimum. In group II, 3 out of 4 CRF patients with normal parathyroid function presented at least 1 maximum and all four patients at least one minimum. One out of 3 CRF patients with hyperparathyroidism presented 2 maximum and all three at least one minimum. Despite pulsatile character intact PTH levels were maintained all the time within the normal range in control group and in CRF patients with normal parathyroid function. In CRF patients with hyperparathyroidism intact PTH changes were restricted within a level of hyperparathyroidism. Ionized calcium levels in control group remained virtually constant along the period and in CRF group fluctuated widely. Parathyroid hormone is secreted in a pulsatile fashion in normal subjects and in patients with chronic renal failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Subclavian catheter-related infection is a major risk factor for the late development of subclavian vein stenosis.

Although subclavian vein stenosis is a well-known complication of haemodialysis subclavian catheters, little is known about its causes. Catheter-related infection is the most common complication of this technique, but its role in the genesis of late subclavian stenosis has not been established. We retrospectively analysed 80 subclavian catheterizations in a total of 54 chronic haemodialysis patients from a single center. Sixteen catheters had to be removed because of a well documented catheter-related infection: three catheter-related sepsis (2 with ipsilateral phlebitis), seven isolated fever with catheter tip colonization which disappeared after catheter removal, and six exit-site discharge with positive culture. For comparison we matched 14 contemporaneous catheters which were electively removed without evidence of infection and with a negative culture of the catheter tip. A venogram of the ipsilateral arm was performed in all the cases after more than 6 months of catheter removal. Both groups were remarkably similar with respect to age, sex, side of insertion, number of inserted catheters, time of indwelling, and time elapsed from removal to venography. Definite subclavian stenosis was three times more common among patients with previous catheter-related infection (75% versus 28%; P < 0.01). Interestingly, both patients with ipsilateral phlebitis showed total occlusion of the subclavian vein. Although all diabetic patients of the study (n = 6) suffered a catheter-related infection, the incidence of late subclavian stenosis was not more common than in non-diabetic infected patients. In summary, subclavian haemodialysis catheter-related infection is a major risk factor for the development of late subclavian vein stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Recurrence of hyperparathyroidism after total parathyroidectomy with autotransplantation: a new technique to localize the source of hormone excess.

The diagnosis of persistent or recurrent hyperparathyroidism after total parathyroidectomy with autograft in the forearm needs a correct assessment of graft function. In 6 patients with relapsing hyperparathyroidism after total parathyroidectomy with forearm implant, total ischaemic blockade of the arm bearing the parathyroid graft, produced a 'temporal implantectomy' with reduction of iPTH in those with graft hyperfunction. In 2 patients with proved supernumerary gland, total ischaemia of the 'graft' was not followed by iPTH changes. Total ischaemic blockade of the arm bearing the parathyroid graft is a valuable method for a correct assessment of graft function. It gives useful information in order to avoid or indicate a reoperation of the neck in patients who had previously undergone parathyroidectomy.