Generation of Paramoeba perurans clonal cultures using flow cytometry and confirmation of virulence.

Amoebic gill disease (AGD) in farmed Atlantic salmon is caused by the amoeba Paramoeba perurans. The recent establishment of in vitro culture techniques for P. perurans has provided a valuable tool for studying the parasite in detail. In this study, flow cytometry was used to generate clonal cultures from single-sorted amoeba, and these were used to successfully establish AGD in experimental Atlantic salmon. The clonal cultures displayed differences in virulence, based on gill scores. The P. perurans load on gills, determined by qPCR analysis, showed a positive relationship with gill score, and with clonal virulence, indicating that the ability of amoebae to proliferate and/or remain attached on gills may play a role in virulence. Gill scores based on gross signs and histopathological analysis were in agreement. No association between level of gill score and specific gill arch was observed. It was found that for fish with lower gill scores based on histopathological examination, gross examination and qPCR analysis of gills from the same fish were less successful in detecting lesions and amoebae, respectively.

Susceptibility of goldsinny wrasse, Ctenolabrus rupestris L. (Labridae), to viral haemorrhagic septicaemia virus (VHSV) genotype III: Experimental challenge and pathology.

Cleaner fish, such as wrasse, are being increasingly used to combat the sea lice infestation of Atlantic salmon (Salmo salar L.) in many European countries. To determine susceptibility of the goldsinny wrasse (Ctenolabrus rupestris L.) and pathogenesis of the viral haemorrhagic septicaemia virus (VHSV) genotype III isolate 12-654, previously associated with VHSV infection in the Shetland Islands in 2012, fish were experimentally challenged by intraperitoneal injection (IP), bath immersion and cohabitation routes. Cumulative proportion of moribund wrasse reached 17% following the virus immersion challenge while by the IP-route moribunds exceeded 50% within 14days post-challenge. Typical signs of VHS as reported in rainbow trout (Oncorhynchus mykiss), were not observed in moribund goldsinny wrasse. The most pronounced histopathological changes, consistent regardless of the route of infection, were observed within the heart and included atrium myofibril degeneration, focal infiltration and multifocal necrosis, with prominent swelling of the endocardium and occasional detachment. Pathological changes in the atrium were associated with presence of the viral antigen as confirmed by a positive immunohistochemical staining. Virus clearance and heart tissue recovery were noted although further experiments are required to confirm these observations. The results of a cohabitation experiment confirmed that goldsinny wrasse shed viable virus and therefore represent a risk of virus transmission to other VHSV susceptible species. Similarities between the pathology in goldsinny wrasse induced through the controlled experimental challenges and that of wrasse spp. from an infection occurrence in Shetland are discussed.

Birmingham hip resurfacing arthroplasty: a series of 110 consecutive hips with a minimum five-year clinical and radiological follow-up.

We report the outcome at a minimum of five years of 110 consecutive metal-on-metal Birmingham Hip Resurfacing arthroplasties in 98 patients. The procedures were performed between October 1999 and June 2002 by one surgeon. All patients were followed up clinically and radiologically. The mean follow-up was 71 months (60 to 93). Revision of either component was defined as failure. The mean Harris Hip score at follow-up was 96.4 (53 to 100). The mean Oxford hip score was 41.9 (16 to 57) pre-operatively and 15.4 (12 to 49) post-operatively (p < 0.001). The mean University of California Los Angeles activity score was 3.91 (1 to 10) pre-operatively and 7.5 (4 to 10) post-operatively (p < 0.001). There were four failures giving a survival at five years of 96.3% (95% confidence interval 92.8 to 99.8). When applying a new method to estimate narrowing of the femoral neck we identified a 10% thinning of the femoral neck in 16 hips (14.5%), but the relevance of this finding to the long-term outcome remains unclear. These good medium-term results from an independent centre confirm the original data from Birmingham.

Fatal pulmonary embolism, death rates and standardised mortality ratios after primary total hip replacement in a joint replacement centre.

We determined retrospectively the postoperative mortality and fatal pulmonary embolism (PE) rates in 1275 consecutive primary total hip replacements (THR) in the six-week period after surgery at an orthopaedic hospital. Patients were traced by questionnaires, outpatient appointments and by telephone. Post-mortem records were used to verify cause of death. Follow-up was 100%. The death rate from PE was 0.16% (CI 0.04%-0.57%) and the all-cause mortality rate was 0.47% (CI 0.22%-1.02%). All deaths were within the first 10 days during the initial hospitalisation. The patient mortality was compared with the population mortality for England and Wales, using standardised mortality ratios (SMRs). The SMR for both sexes combined was 1.08 (CI 0.4-2.36). We observed a lower mortality in females (SMR=0.58; CI 0.07-2.09) but a higher mortality in males (SMR=1.91; CI 0.52-4.9) during the first 42 postoperative days compared to the general population. Fatal PE after THR without routine chemical thromboprophylaxis is uncommon. The death rate in patients undergoing THR appears to be similar to that in the general population.

Pain and satisfaction after hip replacement: The patients perspective at 5 - 12 years.

We present the results of a postal evaluation of 1700 hip replacements performed in 1560 patients at a specialist joint replacement centre. This 5 12 year follow-up assesses the patients perspective of satisfaction, pain levels, revision and dislocation rates, subjective issues related to the prosthetic hip and limitations to daily activities. Our adjusted response rate was 81.4%, with 89.2% of the respondents being satisfied with their hip replacement; 4.1% were dissatisfied, and 5.0% were unsure. 79% of patients reported no pain or slight pain, 14.5% had moderate pain and 2.6% had severe pain. 4.6% of the hip replacements had been revised, and 4.1% had dislocated. The hip was felt to be a limiting factor in their life by 18.4% of patients. The use of a questionnaire has provided long-term follow-up data at far less cost and considerably less inconvenience to the patient than a clinical review. We conclude that pain and patient satisfaction could be used as a simple screening tool for the vast majority of the patients. In those that have moderate or severe pain or express a lack of satisfaction for any reason, further clinical and radiological assessments could be carried out. (Hip International 2005; 15: 112-8).

Venous leg ulcers after hip replacement. A clinical evaluation at 5 to 12 years.

Venous ulceration is a chronic disabling complication of deep-vein thrombosis. The aim of this study was to estimate the incidence of venous leg ulcers five years or more after total hip replacement (THR) and to investigate some of the clinical features associated with their development. We carried out a postal survey of all patients who had undergone a THR 5 to 12 years previously. Replies from 816 patients showed that 66 (8.1%) had a history of leg ulcers. The prevalence of active ulceration was 2.6% and 43 patients (5.3%) reported developing ulceration since their hip replacement. A clinical review determined that 31 (3.8%) of these were true venous ulcers. The ulcers occurred more commonly on the operated side and developed at a mean of 5.8 years (18 months to 12 years) after the first arthroplasty. A mean of 1.9 arthroplasties (1 to 5) (primary and revision) were carried out before the ulcers appeared. The overall incidence of ulcers was similar to that in the general population.

Non-operative management of a peri-prosthetic subcapital fracture after metal-on-metal Birmingham hip resurfacing.

We describe a patient who sustained a peri-prosthetic fracture of the femoral neck two weeks after undergoing a resurfacing procedure for osteoarthritis of the hip. The fracture was minimally displaced and a satisfactory outcome was obtained following conservative treatment.

Audit of ankle fracture fixation in the elderly.

To assess the results of operative treatment of ankle fractures in the elderly, we have reviewed the results of ankle fracture fixation in 76 patients aged over 50 years. This was carried out with special reference to the early complications. Our series had a 1.8% incidence of infection and a 5.2% incidence of delayed healing and wound necrosis. Malunion occurred in 7.9% of patients, and was due in all cases to either imperfect peroperative reduction or inadequate fixation. In no case did fixation fail because of poor bone quality. We conclude that internal fixation of ankle fractures in the elderly carries acceptable risks, so long as careful attention is paid to surgical technique, and fixation is in accordance with AO/ASIF principles.

Early detection of avascular necrosis of the femoral head by MRI.

We used MRI to examine the hips of 32 asymptomatic patients at 9 to 21 months after renal transplantation covered by high-dose corticosteroids. Five hips in three patients showed changes which indicate avascular necrosis, although radiographs, CT scans and isotope scans were normal. These patients had repeat MRI scans after another two years and three years. One patient with bilateral MRI changes developed symptoms and abnormal radiographs and CT and isotope scans in one hip nine months after the abnormal MRI. Intraosseous pressure was found to be raised in both hips, and core biopsies revealed necrotic bone on both sides. The other three hips have remained asymptomatic with unchanged MRI appearances three years after the initial MRI. It seems that idiopathic avascular necrosis does not always progress to bone collapse in the medium term.

A venous foot pump reduces thrombosis after total hip replacement.

In a prospective, randomised controlled trial, the efficacy of the A-V Impulse System in the prevention of deep-vein thrombosis was investigated in 84 patients who had undergone total hip replacement. The incidence of venographically proven, and clinically significant postoperative deep-vein thrombosis was 40% in the control group and 5% in the treatment group (p less than 0.001). No adverse reactions were recorded.

Efficacy of fixed minidose warfarin prophylaxis in total hip replacement.

OBJECTIVE: To determine whether a small fixed perioperative dose of warfarin would prevent deep vein thrombosis after total hip replacement. DESIGN: Prospective, randomised, double blind placebo controlled trial. SETTING: Winford Orthopaedic Hospital, Bristol. SUBJECTS: 148 patients having primary total hip replacement. INTERVENTION: Warfarin 1 mg given daily for one week before and three weeks after surgery. MAIN OUTCOME MEASURE: Deep vein thrombosis diagnosed by the iodine-125 labelled fibrinogen uptake method. RESULTS: Deep vein thrombosis occurred in 25 (34%) of the patients given warfarin and 19 (26%) of the controls (difference 8%; 95% confidence interval -6.8% to 22.8%). CONCLUSION: Fixed minidose warfarin does not prevent deep vein thrombosis after total hip replacement.

Klinefelter's syndrome associated with breast carcinoma and Paget's disease of the nipple.

We describe a patient with Klinefelter's syndrome associated with multi-focal breast carcinoma and Paget's disease of the nipple. Reviewing the 16 previously documented cases in the world literature, it is apparent that patients with this syndrome have an increased incidence of breast carcinoma. There is no evidence to date to suggest that such tumour is morphologically or biologically different from breast cancer in females and normal men.