Detection of African swine fever virus by loop-mediated isothermal amplification.

A loop-mediated isothermal amplification (LAMP) assay was developed for the detection of African swine fever virus (ASFV). This assay targets the topoisomerase II gene of ASFV and its specificity was confirmed by restriction enzyme digestion of the reaction products. The analytical sensitivity of this ASFV LAMP assay was at least 330 genome copies, and the test was able to detect representative isolates of ASFV (n=38) without cross-reacting with classical swine fever virus. The performance of the LAMP assay was compared with other laboratory tests used for ASF diagnosis. Using blood and tissue samples collected from pigs experimentally infected with ASFV (Malawi isolate), there was good concordance between the LAMP assay and real-time PCR. In addition to detecting the reaction products using either agarose gels or real-time PCR machines, it was possible to visualise dual-labelled biotin and fluorescein ASFV LAMP amplicons using novel lateral flow devices. This assay and detection format represents the first step towards developing a practical, simple-to-use and inexpensive molecular assay format for ASF diagnosis in the field which is especially relevant to Africa where the disease is endemic in many countries.

Polycystic kidneys: a cautionary story.

We describe the imaging appearances of a patient with bilateral, synchronous, multiloculated renal cell carcinoma with a predominantly cystic nature. The patient had progressive chronic renal failure. He was initially erroneously diagnosed as having autosomal dominant polycystic kidney disease (ADPKD) on the basis of the imaging findings. We believe this to be the first report describing bilateral synchronous renal carcinomas replacing the renal parenchyma imitating ADPKD.

High-flow nasal cannula as a device to provide continuous positive airway pressure in infants.

OBJECTIVE: To measure the intrapharyngeal pressure (IPP) generated by high-flow nasal cannula (HFNC) at varying flow rates up to 5 l min(-1). STUDY DESIGN: We studied 14 infants on HFNC or NCPAP using IPP manometry to measure the IPP generated at flows of 1, 2, 3, 4 and 5 l min(-1). RESULT: On average flow rates of 1, 2, 3, 4 and 5 l min(-1) generated an IPP (cm of H(2)O) of 1.70+/-0.34, 1.75+/-0.2, 2.62+/-0.28, 3.78+/-0.44 and 4.84+/-0.51 respectively. CONCLUSION: HFNC delivers significant IPP and is potentially a well-tolerated and viable option to provide CPAP at flows of > or = 3 min(-1) in infants with respiratory distress.

Bacterial meningitis--complication from a dialysis catheter.

Various infective complications associated with dialysis catheter infection have been reported in the literature previously. We report a case of a hemodialysis patient presented with confusion and dysarthria secondary to Staphylococcus aureus septicemia and meningitis originating from a tunneled catheter used for providing dialysis. Blood cultures from the periphery, central venous catheter and culture of the line tip grew methicillin-sensitive Staphylococcus aureus. Lumbar puncture after CT brain confirmed Staphylococcus aureus. He was treated with high dose of an appropriate parenteral antibiotic and also removal of the infected line. In spite of optimal treatment, he died 15 days following his admission. The ideal option will be to use a definitive access like a fistula or AV graft, but in practice a significant proportion of hemodialysis patients is dialyzed with temporary or tunneled catheters all over the world, and infection poses a serious threat to dialysis patients resulting in significant mortality and morbidity. In patients with dialysis catheter-related sepsis, removal of the infected catheters and appropriate antibiotic treatment will prevent serious metastatic complications. Planning definitive access well ahead in chronic kidney disease patients and minimizing the use of temporary access is the only way forward.

A 5-year audit of haemodialysis access.

This is a review of our experience with vascular access procedures over a 5-year period at Derriford Hospital, Plymouth, UK. The aims of the study were to examine the outcome of vascular access procedures and factors influencing access survival. Between April 1995 and March 2000, 151 patients who underwent 221 vascular access procedures were studied. Of these, 136 had autogenous arteriovenous fistulae, whereas 85 had prosthetic AV grafts (41% in the thigh). The overall primary failure rate was 21% whereas the 1- and 5-year cumulative access survival rates were 60 and 41%, respectively. Thigh grafts have a mean survival of 36 months compared with 32 months for prosthetic upper limb and 43 months for autogenous fistulae. Age, diabetes and predialysis status did not significantly influence access survival. Thrombosis was responsible for access failure in 62 cases (28%). Avoiding subclavian vein canulation and performing vessel mapping prior to access placement should reduce the risk of access failure due to outflow obstruction.

A study of cytokine gene polymorphisms and protein secretion in renal transplantation.

Although there is evidence that cytokine gene polymorphisms are associated with varying quantities of cytokine protein production, the exact role of these polymorphisms in allograft rejection remains unclear. In a previous study, we demonstrated a significant association between high IL-10 secretion in mixed lymphocyte culture (MLC), together with HLA mismatching for at least 4-6 antigens, with the occurrence of acute rejection following renal transplantation. We, therefore, wished to ascertain whether cytokine gene polymorphisms are associated with varying levels of protein secretion and/or allograft rejection in the same group of patients. Cytokine protein secretion in MLC for IL-4, IL-6, IL-10 and IFN-gamma was measured by ELISA in 49 patient-donor pairs. Protein secretion for the above cytokines was also measured in phytohaemagglutinin (PHA) stimulated cultures in 30 normal controls. In both patient and control groups, single nucleotide polymorphism analysis for IL-4 G(-590)T, IL-6 G(-174)C, IL-10 G(-1082)A, IL-10 C(-819)T, IL-10 C(-592)A, TNF-alpha G(-308)A and microsatellite analysis for IFNG (CA repeat) was performed. No correlation was found between cytokine gene polymorphisms and cytokine protein secretion in either mitogen stimulated cultures (control group) or MLC (patient group). In addition, no correlation was demonstrated between cytokine gene polymorphisms and renal allograft rejection.

Cytokine secretion in mixed lymphocyte culture: a prognostic indicator of renal allograft rejection in addition to HLA mismatching.

We have previously demonstrated significant inter-individual variations in cytokine protein secretion between normal individuals and patients prior to renal transplantation. In this study, pre-transplant patient vs. donor mixed lymphocyte cultures (MLC) were set up between 57 renal allograft patient/donor pairs, and secretion of cytokine protein (IL-2, IL-4, IL-6, IL-10 and IFN-gamma) into the culture supernatant measured by ELISA. Significant inter-individual variations in protein secretion in MLC were observed for all cytokines studied. Univariate analysis demonstrated that high levels of IFN-gamma and IL-10 in MLC and spontaneous IL-4, together with female donor sex and a high degree of HLA mismatching (especially HLA-DR) were significantly associated with rejection. However, multivariate analysis revealed the greatest risk of rejection (RR = 25.5, P = 0.003) was associated with a combination of high IL-10 secretion in MLC and mismatching for at least four HLA antigens (HLA-A, -B and -DR). It remains to be determined whether cytokine secretion in MLC is linked to cytokine gene polymorphisms. In future, assays for measuring either cytokine secretion or genetic polymorphisms may prove to be useful in aiding donor selection and tailoring immunosuppressive therapy.

HLA-DR typing for kidney transplants: advantage of polymerase chain reaction with sequence specific primers in a routine hospital laboratory.

AIMS: To determine whether the polymerase chain reaction with sequence specific primers (PCR-SSP) can assign HLA-DR type more accurately than serology in a routine hospital laboratory. METHODS: The 93 patients currently awaiting kidney transplants have been DR typed by serology over the past 14 years, 82% within the past five years. They have now been retyped using the PCR-SSP method described by Bein et al. Where the two results differed, PCR-SSP was repeated, once by the same method and once using the primer set of Olerup and Zetterquist. RESULTS: There were 13 (14%) discrepancies between the results. Of these, two were PCR-SSP failures, later overcome: three were failure to detect DRB1*0103 by serology; five assignment of other alleles by PCR-SSP to serological "blanks"; and three alleles were differently assigned by serology and PCR. The serological typing of the final patient when repeated for this study was at variance with the original findings (14 years ago), but in agreement with PCR. In the remaining patients, serology had not determined the split of 36 DR3 alleles (all DR17 by PCR-SSP) or 13 DR6 alleles (12 DR13 and one DR14 by PCR-SSP). One patient in each case had their antigen splits of DR2 and DR5 assigned by PCR-SSP (DR15 and DR11, respectively) but not by serology. CONCLUSIONS: PCR-SSP provides more reliable and detailed information on HLA-DR polymorphism than serology, and does so within a routine tissue typing laboratory.

The dialysis debate: acute renal failure in burns patients.

Acute renal failure is an uncommon occurrence in burns patients, although the mortality of this condition remains high. We review briefly the literature on the incidence and management of acute renal failure in burns patients. We discuss the results of a questionnaire sent to all units in the UK examining this problem. Our findings suggest that acute renal failure is usually part of a complex multiorgan failure. However, an aggressive approach in the management of these patients can result in a significant improvement in prognosis, in the absence of a greater understanding of prevention of the condition. We have suggested measures that could be taken to aid the care of burns patients with renal failure.

Glomerulonephritis in rheumatoid arthritis.

We present data on 10 patients with RA who developed glomerulonephritis which was not related to gold or penicillamine therapy. Although two of these patients had received gold this had been discontinued 13 and 18 yr before the diagnosis of glomerulonephritis. Seven patients presented with nephrotic syndrome and three with proteinuria and microscopic haematuria. Renal histology showed a membranous nephropathy (five patients), mesangial IgA nephropathy (two patients), focal segmental necrotizing glomerulonephritis (two patients) and focal segmental glomerulosclerosis (one patient).

Prognostic factors in acute renal failure following aortic aneurysm surgery.

This study analyses the prognostic factors associated with survival in 70 patients who developed acute renal failure following surgery for an aortic aneurysm. Forty-nine patients (70 per cent) had surgery for a ruptured aortic aneurysm and 21 patients (30 per cent) had an elective procedure. Fifty-nine patients received haemodialysis. Thirty-three patients (47 per cent) survived the episode of acute renal failure. Six of these thirty-three patients died within three months of recovering from acute renal failure, giving an overall survival of 27/70 (39 per cent). A stepwise logistic regression analysis showed that the following factors significantly adversely affected survival: a need for inotropic support, ventilation for more than three days and age over 65 years. A model developed using these variables provided a basis for predicting outcome.

Chronic ambulatory peritoneal dialysis in patients aged over seventy.

Thirteen patients with end-stage renal disease aged 70 years have been successfully treated by chronic dialysis treatment. Despite many problems associated with the elderly, a good quality of life was achieved.

The treatment of diabetic renal failure by continuous ambulatory peritoneal dialysis.

During the 6-year period 1981-1987, 309 patients started chronic ambulatory peritoneal dialysis (CAPD), of whom 75 (24%) had diabetes. Despite severe peripheral vascular problems (20%), ischaemic heart disease (90%), and complete blindness (21%) the 1-year patient survival on CAPD was 88%. The actuarial patient survival for diabetic patients was similar to that of the non-diabetic cohort over the first 18 months but fell to 48% (compared to 70% in non-diabetic patients) at 3 years. Complications associated with CAPD, including the incidence of peritonitis, were no different between the diabetic and non-diabetic patient populations. Successful treatment for end-stage renal disease (ESRD) in diabetic patients can be achieved and justified in a liberal selection programme for the treatment of diabetic ESRD.

Selective conversion from azathioprine to cyclosporin for steroid-resistant rejection in renal transplants: an alternative therapy.

In 153 consecutive renal allograft recipients whose initial immunosuppression was prednisolone and azathioprine, 41 developed acute rejection episodes that were not reversed by 5-9 g of intravenous methylprednisolone. Renal histology showed cellular rejection in ten patients, vascular rejection in 12, and mixed cellular and vascular rejection in 16. Thirty-one patients were converted to cyclosporin in the first month post-transplant and ten in the second month. At the time of conversion, 20 patients were dialysis dependent and in the remainder the mean serum creatinine was 353 mumol/l (range 139-548 mumol/l). Renal function improved in 31 patients after conversion. Ten patients lost their grafts, of whom seven were on dialysis. There were no deaths and the 1-year graft survival was 75%. These data suggest that conversion from azathioprine to cyclosporin because of steroid-resistant rejection is an effective and safe strategy in patients whose initial immunosuppression is prednisolone and azathioprine.

Vancomycin and ceftazidime in the treatment of CAPD peritonitis.

102 episodes of continuous ambulatory peritoneal dialysis (CAPD) peritonitis were studied prospectively during a 288-day period at The Queen Elizabeth Hospital, Birmingham. Organisms were isolated from 76% of the episodes, with coagulase-negative staphylococci, being the most commonly encountered organism (55%). Initial treatment consisted of intraperitoneal vancomycin and ceftazidime with subsequent adjustment on the basis of antibiotic sensitivities. With this regimen, 83% of the positive cultures became negative by 72 h, 9.8% of cases relapsed and removal of the CAPD catheter was necessary in 8 patients (7.8%). Overall, 92% of cases were cured. No adverse drug reactions were seen. This combination of antibiotics appears effective and safe in the treatment of CAPD peritonitis.