Human herpesvirus 6 seronegativity before transplantation predicts the occurrence of fungal infection in liver transplant recipients

BACKGROUND

Invasive fungal infection has a major impact on the morbidity and mortality of liver transplant recipients. Human herpesvirus (HHV)-6 infection after transplantation is associated with an immunosuppressive state and the development of cytomegalovirus disease. Because cytomegalovirus infection is a risk factor for invasive fungal infection after transplantation, we have examined whether HHV-6 and fungal infection are associated after transplantation.

METHODS

Pretransplantation sera from 247 consecutive liver transplant recipients were analyzed for IgG to HHV-6. Thirty-three (13%) HHV-6-seronegative recipients were identified. Six of 33 (18%) seronegative recipients experienced fungal infection as compared with 15 of 214 (7%) seropositive recipients (P=0.034).

RESULTS

In a univariate analysis of risk factors for fungal infection, pretransplantation seronegativity to HHV-6 (P=0.034), intraoperative cryoprecipitate requirements greater than the 75th percentile (P=0.035), reoperation (P=0.005), biliary stricturing postoperatively (P=0.046), and gastrointestinal or vascular complications postoperatively (P=0.030) were identified as significant risk factors. Moreover, in pairwise multivariate analysis, pretransplantation HHV-6 seronegativity remained a significant variable even in the presence of each of the other variables.

CONCLUSIONS

These results suggest that HHV-6 seronegativity before transplantation is a valuable clinical marker that identifies patients at risk for developing fungal infection after transplantation.

Improved prognosis of thoracic aortic aneurysms: a population-based study

CONTEXT

Managing thoracic aortic aneurysms identified incidentally by increased use of computed tomography, echocardiography, and magnetic resonance imaging is problematic, especially in the elderly.

OBJECTIVE

To ascertain whether the previously reported poor prognosis for individuals with thoracic aortic aneurysms has changed with better medical therapies and improved surgical techniques that can now be applied to aneurysm management.

DESIGN

Population-based cohort study.

SETTING AND PATIENTS

All 133 patients with the diagnosis of degenerative thoracic aortic aneurysms among Olmsted County, Minnesota, residents between 1980 and 1994 compared with a previously reported cohort of similar patients between 1951 and 1980.

MAIN OUTCOME MEASURES

The primary clinical end points were incidence, cumulative rupture risk, rupture risk as a function of aneurysm size, and survival.

RESULTS

In contrast to abdominal aortic aneurysms, for which men are affected predominately, 51% of thoracic aortic aneurysms were identified in women who were considerably older at recognition than men (mean age, 75.9 vs 62.8 years, respectively; P= .01). The overall incidence rate of 10.4 per 100000 person-years (95% confidence interval [CI], 8.6-12.2) between 1980 and 1994 was more than 3-fold higher than the rate from 1951 to 1980. The cumulative risk of rupture was 20% after 5 years. Seventy-nine percent of ruptures occurred in women (P= .01). The 5-year risk of rupture as a function of aneurysm size at recognition was 0% for aneurysms less than 4 cm in diameter, 16% (95% CI, 4%-28%) for those 4 to 5.9 cm, and 31% (95% CI, 5%-56%) for aneurysms 6 cm or more. Overall 5-year survival improved to 56% (95% CI, 48%-66%) between 1980 and 1994 compared with only 19% between 1951 and 1980 (P<.01).

CONCLUSIONS

In this population, elderly women represent an increasing portion of all patients with clinically recognized thoracic aortic aneurysms and constitute the majority of patients whose aneurysm eventually ruptures. Overall survival for thoracic aortic aneurysms has improved significantly in the past 15 years.

Primary chondrosarcoma of long bones and limb girdles

BACKGROUND

Chondrosarcomas are common solid malignant tumors of bone, second in incidence only to osteosarcomas. The biologic evolution of chondrosarcomas is slow, requiring long follow-up intervals for meaningful survival analysis.

METHODS

This study describes the clinicopathologic profiles of 344 patients, 194 male and 150 female (M:F, 1.3:1.0), with primary chondrosarcoma of long bones and limb girdles seen at 1 institution over a period of 80 years.

RESULTS

The average age at presentation was 46 years (range, 5-82 years). The pelvis was the most common location (1.7% of all patients). Local pain was the most frequently reported initial symptom (81.4%). Survival analysis was limited to 233 patients whose primary treatment was given at the Mayo Clinic. All 233 patients had potential follow-up of at least 5 years. The overall 5-year survival rate was 77% (the expected rate was 96%). Local recurrence developed in 19.7% of patients and metastatic lesions in 13.7%. The recurrence rate was higher for tumors of the shoulder and pelvis than for tumors of long bones. Radiographically, chondrosarcomas had a characteristic appearance, including a combination of bone expansion and cortical thickening. Entering the tumor at surgery increased the risk of local recurrence. Histologic tumor grade was an important predictor of local recurrence and metastasis.

CONCLUSIONS

With adequate initial surgical intervention, chondrosarcoma is primarily a local disease with a low metastatic rate.

Risk factors for prosthetic joint infection: case-control study

We conducted a matched case-control study to determine risk factors for the development of prosthetic joint infection. Cases were patients with prosthetic hip or knee joint infection. Controls were patients who underwent total hip or knee arthroplasty and did not develop prosthetic joint infection. A multiple logistic regression model indicated that risk factors for prosthetic joint infection were the development of a surgical site infection not involving the prosthesis (odds ratio [OR], 35.9; 95% confidence interval [CI], 8.3-154.6), a National Nosocomial Infections Surveillance (NNIS) System surgical patient risk index score of 1 (OR, 1.7; 95% CI, 1.2-2.3) or 2 (OR, 3.9; 95% CI, 2.0-7.5), the presence of a malignancy (OR, 3.1; 95% CI, 1.3-7.2), and a history of joint arthroplasty (OR, 2.0; 95% CI, 1.4-3.0). Our findings suggest that a surgical site infection not involving the joint prosthesis, an NNIS System surgical patient risk index score of 1 or 2, the presence of a malignancy, and a history of a joint arthroplasty are associated with an increased risk of prosthetic joint infection.

Cytomegalovirus and its association with hepatic artery thrombosis after liver transplantation

BACKGROUND

Hepatic artery thrombosis (HAT) is a cause of morbidity and graft loss in approximately 7% of patients after an orthotopic liver transplantation (OLT). Although technical problems are often thought to be the cause of HAT, in general the etiology remains unclear. Because cytomegalovirus (CMV) can infect endothelial cells in vitro and lead to a rapid procoagulant response, it can be hypothesized that, in the absence of CMV antibodies, latent CMV in an allograft may become activated and promote or contribute to vascular thrombosis. Therefore, the purpose of this study was to examine the relationship between CMV serology of the donor and recipient with the development of HAT after OLT.

METHODS

Between July 1988 and November 1995 (University of Wisconsin era), 490 OLTs were performed in 413 patients. Subsequently, four patients were excluded in whom the CMV serology results of the donor were not available. Sixteen of the 409 patients developed HAT within 30 days after liver transplantation. The control group consisted of the other 393 patients.

RESULTS

The incidence of HAT was 12.5% in 64 CMV D+R- patients and 0% in 52 CMV D-R- patients. However, in the other combinations (D+R+ and D-R+), the incidence was only 2.8% (P = 0.005). Eight of the 16 patients with HAT belonged to the CMV D+R- group.

CONCLUSIONS

We conclude that CMV-seronegative patients receiving a seropositive allograft may be at risk for early HAT. Seropositivity of the donor alone and of the recipient alone was not significantly related to the incidence of HAT. Prophylactic treatment with ganciclovir and/or anticoagulation should be evaluated to prevent this complication.

Transabdominal preperitoneal laparoscopic inguinal herniorrhaphy: assessment of initial experience

OBJECTIVE

To evaluate our initial experience with laparoscopic inguinal herniorrhaphy.

DESIGN

We retrospectively studied a consecutive series of patients selectively chosen for laparoscopic repair of inguinal hernia.

MATERIAL AND METHODS

The study cohort consisted of 173 patients treated by a single surgeon between 1992 and 1995. For all operations, a transabdominal approach was used. Follow-up was obtained by telephone contact or letter.

RESULTS

The study group consisted of 167 male and 6 female patients with a mean age at operation of 55 years (range, 15 to 81). During the study period, 206 laparoscopic inguinal hernia repairs were performed in the 173 patients. Only one patient (0.6%) required conversion to laparotomy. Bilateral hernia repair was done in 31 patients (18%). Of the 206 procedures, 63 repairs (31%) were performed for recurrent hernias. In 69% of the patients, the procedure was completed on an outpatient basis. Early postoperative complications necessitating surgical intervention occurred in four patients. The median time to return to work or normal physical activity was 7 days for unilateral and 12 days for bilateral hernia repair (P = 0.18). A mean follow-up of 29 months was obtained for 171 patients (99%). In six patients (3%), a recurrent hernia developed. Four of these six patients had previously undergone an open surgical procedure on the side of the recurrence.

CONCLUSION

Laparoscopic inguinal herniorrhaphy is a feasible alternative to open hernia repair. This operation, however, should be reserved for selected patients. Longer follow-up and controlled trials comparing laparoscopic and tension-free open herniorrhaphy are necessary for assessment of the relative benefits of this procedure.

Surgical management of intrahepatic cholangiocarcinoma: a 31-year experience

Intrahepatic cholangiocarcinoma (ICC) is the second most common malignant primary tumor of the liver. It is, though, a rare tumor and little is known regarding its natural history, clinicopathologic characteristics, or the outcomes of surgical therapy. We reviewed the experience of 61 patients with ICC seen by the surgical service at the Mayo Clinic over a 31-year period. Patient demographic and clinical data were recorded, as were survival statistics. Pathologic data were also obtained and patients stratified according to the TNM classification. Twenty-eight patients were resected for cure. Overall, 45 patients died of ICC. Of the patients resected for cure, survival at 3 years was 60%. No pathologic condition was found to be associated with the development of ICC. Overall survival correlated with stage of the tumor. Among patients resected for cure, stage did not correlate with survival. Prognosis for patients with ICC remains poor; resection, though, appears to prolong survival.

Advanced multiple beam equalization radiography: receiver operating characteristic comparison with screen-film chest radiography

OBJECTIVE

To test the hypothesis that the advanced multiple beam equalization radiography (AMBER) imaging system is superior to conventional chest radiography in the demonstration of diffuse infiltrative lung disease, emphysema, pulmonary nodules, calcification within nodules, and mediastinal or hilar masses and lymphadenopathy.

MATERIAL AND METHODS

The study involved 115 patients, each of whom underwent chest computed tomography (CT), AMBER, posteroanterior chest radiography, and conventional posteroanterior stereoscopic chest radiography (two films). All radiographs were obtained with the InSight Thoracic Imaging System. Four chest radiologists independently analyzed the 115 AMBER studies, 115 unpaired single conventional radiographs (a single film from a stereoscopic pair), and 115 stereoscopic conventional radiographs (2 films) for the presence of diffuse infiltrative lung disease, emphysema, pulmonary nodules, calcification within nodules, and mediastinal or hilar masses and lymphadenopathy. For each abnormality detected, the radiologists described their level of confidence based on a scale of 1 to 5. The 115 CT examinations were interpreted by consensus among 3 of the chest radiologists. The CT results were considered the standard. Receiver operating characteristic (ROC) techniques were used for statistical analysis.

RESULTS

No statistically significant differences were found with ROC techniques between the AMBER system and single or stereoscopic conventional screen-film radiography for the abnormalities studied.

CONCLUSION

We noted no clinically significant difference between AMBER and either single or stereoscopic conventional screen-film radiography in this prospective study of 115 patients in which CT (performed within 1 week of both radiographic examinations) was the standard.

Prognostic factors: guidelines for investigation design and state of the art analytical methods

The proliferation of putative prognostic factors, derived prognostic indices and computerised prediction of outcome in surgical oncology has led to some confusion over the exact methods available for deriving clinically significant prognostic factors. The realisation that the interaction between factors is often complex and non-linear has led to the development of new statistical techniques. The aim of this article is to review the currently available methods of analysis. A review of the relevant literature available from statistical, medical and computer science sources was performed. Information has been conveyed at a level aimed at producing a practical understanding of the techniques involved rather than their underlying mathematical basis. There are now clear guidelines for the investigation of putative prognostic factors (Table 1). The established role of linear statistical models and prognostic indices remains vitally important for the majority of diseases with many derived prognostic indices having been validated in a prospective fashion. However, in order to improve the delineation of prognostic factors other more complex methods of analysis are now being utilised. Furthermore, the recognition of complex dynamic non-linearity within biological systems has led to the increasing use of non-linear statistical techniques and artificial intelligence. As such it is incumbent upon the modern clinician to be able to understand the basic assumptions required for multivariate analysis and also to realise when alternative statistical techniques should be employed.

Can adrenal incidentalomas be safely observed?

We currently recommend excision of adrenal incidentalomas > or = 4 cm in size and all hormonally active tumors. The optimal management and follow-up of smaller nonfunctioning tumors are controversial. The aim of this study was to determine the clinical outcome of a well defined population of patients with incidentalomas followed without operative intervention. The study group comprised 231 patients, identified from the records of abdominal or thoracic computed tomographic (CT) scans performed between 1985 and 1989. The primary outcome variable analyzed was survival. Follow-up was obtained by office records, telephone contact, or letter. There were 101 male and 130 female patients with a mean age at diagnosis of 64 years (range 5-86 years). Most adrenal tumors were unilateral (right 113; left 98); 20 were bilateral. Mean tumor size was 2 cm (range 1-6 cm). In nine (4%) patients the tumor was > or = 4 cm. Follow-up [mean 7 years; range 1 month (patient died) to 11.7 years] was complete in 224 (97%) patients. Ninety-one (39%) patients had one or more additional CT scans performed during the follow-up period, with only four patients demonstrating a > 1 cm increase in the size of the adrenal mass. Surgical excision of these four lesions identified benign pathology. Eighty-one (35%) patients died of conditions unrelated to adrenal pathology. No patient developed subsequent adrenal hyperfunction or adrenal malignancy. Within the context of our guidelines, conservative management of adrenal incidentalomas considered benign or nonfunctioning at diagnosis is appropriate. Additional information provided by repeat CT scanning appears to confer limited benefit. This study does not support laparoscopic removal of small, nonfunctional adrenal tumors, as has been suggested.

Laparoscopic versus open posterior adrenalectomy: comparison of acute-phase response and wound healing in the cushingoid porcine model

This prospective randomized study examined the acute-phase response and wound healing, comparing laparoscopic (LA) and open posterior (PA) adrenalectomy in a cushingoid porcine model. Repository corticotropin gel was given to 40 pigs for 21 days. Biochemical and tissue parameters of Cushing syndrome were confirmed. The pigs were randomized to undergo LA or PA. In addition to operating time and morbidity, the acute-phase response was compared by measuring the postoperative white blood cell count, fasting glucose, C-reactive protein, and nitrogen balance. Wound healing was assessed by (1) scored (1-4) gross appearance at 48 hours and 1 and 2 weeks; (2) histologic examination; and (3) tensile strength. There was no difference in operating time (mean +/- SD) (36 +/- 9 minutes open vs. 37 +/- 7 minutes laparoscopic), perioperative mortality, degree of leukocytosis, fasting glucose, or C-reactive protein (p > 0.05). Nitrogen balance, wound scores, and tensile strength at 24 hours and 1 week were more favorable in the LA group than in the PA group (p < 0.05). In the cushingoid porcine model, laparoscopic adrenalectomy was less catabolic and was associated with fewer wound complications than the open posterior adrenalectomy. These findings provide support for continued pursuit of laparoscopic methods for adrenalectomy in the clinical setting.

Molecular, serological, and clinical features of 16 consecutive cases of invasive streptococcal disease. Southeastern Minnesota Streptococcal Working Group

We performed a comprehensive analysis of the molecular, serological, and clinical features of 16 consecutive cases of invasive streptococcal disease (ISD). The majority of cases were linked to two group A streptococcus (GAS) clones closely related by pulsed-field gel electrophoresis (PFGE) and designated as PFGE-1 and PFGE-1.1. These clones, serotyped as M-3, T-3/B3264, carried an allelic variant of the gene that encodes pyrogenic exotoxin A (speA3) and the gene that encodes streptococcal superantigen (SSA) but different emm alleles that encode M-protein. The characteristics and clinical features of patients were similar to those described in previous reports, regardless of the responsible GAS clone. However, worse clinical outcomes (shock and death) were more frequent when patients infected with PFGE1/1.1 clones were considered as a group and compared with all other patients as a group. One striking feature in some patients with deep tissue infection was a lack of inflammatory cells despite the presence of numerous streptococci. An evaluation of PFGE profiles of GAS isolated elsewhere demonstrated that the PFGE-1 clone has caused invasive disease in other locations in the United States and in Japan.

Development of an adjustable prosthesis for the treatment of gastroesophageal reflux: preliminary results in a porcine model

Dysphagia and recurrent gastroesophageal reflux complicate use of the Angelchik prosthesis. The authors developed an inflatable silicone device, similar to the Angelchik prosthesis, that may allow for the adjustment of the total pressure exerted around the gastroesophageal junction after implantation. To estimate its potential to prevent gastroesophageal reflux in humans, we used a short-term porcine model in which we measured the effective lower esophageal sphincter pressure in 10 anesthetized pigs using a computerized, three dimensional pressure vector volume analysis. Anesthesia and mobilization of the gastroesophageal junction did not modify the three dimensional pressure vector volume at the lower esophageal sphincter. Implantation of the deflated device significantly increased effective lower esophageal sphincter three dimensional pressure vector volume compared with baseline. Inflation of the device with 30 ml of saline further increased lower esophageal sphincter pressure significantly. Deflation of the device returned the pressure to the pre-inflation values. Using an animal model and short-term implantation, this new antireflux device appeared to offer the potential ability to adjust the pressure selectively at the gastroesophageal junction postoperatively. An added future feature of this device may be the ease of insertion using laparoscopic techniques. Long-term animal implantation studies and clinical trials are required to help establish the safety and efficacy of this device in humans.

The natural history of debonding of the femoral component from the cement and its effect on long-term survival of Charnley total hip replacements

Two hundred and ninety-seven consecutive Charnley total hip replacements that had been followed for at least twenty years or until revision or death were analyzed to determine the effect of early debonding of the smooth-surfaced femoral component on its subsequent survival. Radiographically evident debonding was not found to have a significant effect, with the numbers available, on the long-term survival of the femoral component when the maximum thickness of the radiolucent line between the superolateral border of the prosthesis and the cement had been less than 2.0 millimeters during the first one to five years after the operation. The radiographic finding of debonding also was not found to be associated with pain in the hip. These data show that most components with early debonding functioned well during a long period of follow-up and suggest that debonding of a smooth femoral component of a Charnley total hip replacement should not be considered to be analogous to loosening. In contrast, when the maximum thickness of the radiolucent line between the superolateral border of the prosthesis and the cement was 2.0 millimeters or more, an early appearance of debonding was associated with a significantly poorer (p < 0.0001) probability of survival of the Charnley femoral component without revision because of aseptic loosening. Thus, pronounced early subsidence of the component within the cement mantle had a strong negative impact on the long-term performance of the implant. The results of the present study should not be extrapolated to prostheses with substantially different design characteristics, as it appears that different types of femoral components behave differently when debonding occurs.

Comparison of North American Symptomatic Carotid Endarterectomy Trial and population-based outcomes for carotid endarterectomy

PURPOSE

The North American Symptomatic Carotid Endarterectomy Trial (NASCET) advocated the use of carotid endarterectomy (CEA) for transient ischemic attacks (TIAs), nondisabling strokes, and ipsilateral high-grade stenosis in highly selected patients. Whether similar results are achieved when CEA is applied to an entire geographically defined population is unknown but important if the NASCET recommendations are to be applied broadly to all community patients.

METHODS

To determine the survival rate to ipsilateral stroke after CEA for all symptomatic patients in a defined population, we reviewed the medical records of all patients residing in Olmsted County, Minn. (approximately 100,000), who underwent a CEA for TIA or nondisabling stroke between 1970 and 1995. Their outcomes were compared with the NASCET results.

RESULTS

In the community of Olmsted County, 297 patients (108 women and 189 men) underwent 322 CEAs during the study period. TIAs or nondisabling stroke was the indication in 254 patients (86%), whereas the remaining 14% had asymptomatic stenosis. After CEA for symptomatic lesions, survival rate free of ipsilateral stroke was 97% at 2 years, 93% at 5 years, and 92% at 10 years. These results are similar to the NASCET survival rates free of ipsilateral stroke at 2 years (91%). However, the 30-day postoperative stroke rate for patients older than 80 years was significantly higher than that for patients younger than 80 years.

CONCLUSIONS

When the NASCET results are compared with a population-based experience in which all symptomatic patients undergoing CEA were analyzed, the early outcomes were similar. Our population-based data also document the remarkably durable long-term results of CEA in preventing stroke and present another benchmark for carotid stent angioplasty.

Prophylactic oophorectomy in colorectal carcinoma: preliminary results of a randomized, prospective trial

Controversy exists regarding the role of prophylactic oophorectomy during resection for primary colorectal cancer.

PURPOSE

A prospective, randomized trial was initiated to evaluate the influence of oophorectomy on recurrence and survival in patients with Dukes Stages B and C colorectal cancer.

METHOD

Between November 1986 and March 1997, 155 patients were randomized to oophorectomy or no oophorectomy at laparotomy for resection of colorectal cancer.

RESULTS

No incidence of gross or microscopic metastatic disease to the ovary was found among 77 patients randomized to oophorectomy, in contrast to previous reports. Preliminary crude survival curves suggested a survival benefit for oophorectomy between two and three years from surgery, but Kaplan-Meier survival analysis indicated that this was not statistically significant and the benefit does not appear to persist at five years. Kaplan-Meier curves of recurrence-free survival, however, suggest a more substantial separation of the curves, with 80 percent vs. 65 percent five-year disease-free survival for oophorectomy vs. nonoophorectomy, but further patient accrual is necessary to provide sufficient statistical power.

CONCLUSIONS

Occult colorectal carcinoma metastatic to the ovaries has not been documented in this series of putative Dukes Stages B and C tumors. The possibility of a recurrence-free survival advantage emphasizes the need to continue this preliminary work.

Survival after surgical treatment for primary hyperparathyroidism

BACKGROUND

Reports have suggested that patients with primary hyperparathyroidism (pHPT) are at increased risk for premature death, even when they reach normocalcemia. This study addresses factors that may be of relevance for long-term outcome.

METHODS

Between 1980 and 1984, 1052 patients (27% men and 73% women; median age, 59 years) underwent initial cervical exploration for pHPT. Long-term follow-up was obtained with regard to overall survival and cause of death. By using univariate and multivariate (Cox) survival analysis, subgroups of patients were compared.

RESULTS

Median follow-up was 12 years (range, 0 to 15 years). Overall, survival was not decreased compared with the expected survival of a gender- and age-matched midwest population. Survival was better in patients with a history of kidney stones (p = 0.044), without osteoporosis (p = 0.004), and without muscle weakness (p = 0.013).

CONCLUSIONS

Decreased long-term survival was not evident in this study. Age at the time of initial surgical treatment and the degree of endocrine activity of the diseased glands appear to be the most important independent prognostic factors for survival. Comparison of these data to prior Scandinavian data is not justified, principally because of the less advanced stage of disease in this study.

Laparoscopic versus open posterior adrenalectomy: a case-control study of 100 patients

BACKGROUND

Few controlled studies have compared laparoscopic transabdominal adrenalectomy (LA) to conventional open posterior adrenalectomy (PA).

METHODS

Five patients have undergone successful LA at our institution between 1992 and 1996. A matched case-control study of 50 PA patients was performed during a similar time period.

RESULTS

Follow-up was complete in 82% of patients with a mean follow-up time of 25 months. There were no statistically significant differences between the LA and PA groups with regard to the following demographic features: age, gender, endocrine disorder, side and size of tumor, and body habitus. Statistically significant differences (p < 0.05), however, were present (LA vs PA) when we compared the following results: mean hospital stay (3.1 versus 5.7 days), narcotic equivalents (28 versus 48), return to normal activity (3.8 versus 7 weeks), patient satisfaction (9 versus 7 [scale 1 to 10, 10 being most satisfied]), late morbidity (0 versus 54%), and operating room time (167 versus 127 minutes). Median hospital charges ($7,000 versus $6,000) were slightly higher in the LA group (p = 0.05).

CONCLUSIONS

Although LA is technically more demanding and slightly more expensive to perform, advances appear to exist for LA with regard to patient comfort, patient satisfaction, hospital stay, and return to normal daily activities. Late incisional complications are dramatically less in the LA group.

Seroconversion to human herpesvirus 6 following liver transplantation is a marker of cytomegalovirus disease

Human herpesvirus 6 (HHV-6) infection is common after transplantation; HHV-6 is known to interact with other viruses and induce immunosuppression. Whether HHV-6 plays a role in the occurrence of cytomegalovirus (CMV) infection after transplantation was investigated. In a cohort of 247 liver transplant recipients, HHV-6 seroconversion was identified as a significant risk factor for development of symptomatic CMV infection (P < .001), including CMV organ involvement (P < .001), even in the presence of the other significant risk factors: D+/R- CMV serologic status (P < .001) or use of OKT3 after transplantation (P = .002). Subgroup analysis indicated that HHV-6 seroconversion was significantly associated with symptomatic CMV infection in the D+/R+ but not in the D+/R- CMV serologic group (P < .001 and P = .11, respectively). These results indicate that HHV-6 seroconversion is a marker for CMV disease after transplantation and suggest that additional studies using more sensitive diagnostic techniques are warranted to determine the relationship between HHV-6 and CMV infection after transplantation.

Cataract extraction rates in Olmsted County, Minnesota, 1980 through 1994

OBJECTIVE

To analyze population-based trends in cataract extraction.

DESIGN

Rochester Epidemiology Project databases; which capture virtually all health care services provided to residents of Olmsted County, Minnesota, were used to perform retrospective cohort analyses of rates of primary cataract extractions performed between 1980 and 1994.

PARTICIPANTS

The population of Olmsted County, Minnesota.

MAIN OUTCOME MEASURES

Incidence rates adjusted to the age and sex distribution of the 1990 US white population were analyzed using Poisson regression.

RESULTS

The 4257 procedures performed on 3176 patients of all ages represented overall annual age-adjusted rates of 404 procedures per 100,000 females and 320 per 100,000 males. Annual age- and sex-adjusted rates for both sexes combined rose from 133 procedures per 100,000 in 1980 to a peak of 507 per 100,000 in 1992. The rates fell to 470 per 100,000 in 1994. Manual review of a random sample of records estimated case overascertainment at 0.9%.

CONCLUSIONS

With the exception of 1988 and 1989, rates of cataract surgery in this geographically circumscribed population increased every year between 1980 and 1992. Data from 1993-1994 indicate that rates may have plateaued and possibly declined slightly. If sustained, these patterns could have major implications for future utilization of ophthalmologic resources.

Paget's disease of the perianal region--an aggressive disease?

BACKGROUND

Perianal Paget's disease is a rare entity, often associated with internal malignancies and a poor prognosis.

METHODS

A chart review of patients with perianal Paget's disease who presented consecutively to Mayo during 25 years (starting in January 1970) was made. Patients included had Paget's disease located in or around the anus (3 cm). Patients were excluded for evidence of spread of vulvaperineal lesions or pagetoid extension of a rectal adenocarcinoma. Histology slides were reviewed, and immunohistochemistry was applied to confirm diagnoses. Follow-up was updated in all patients. Recurrence and survival curves were generated by the Kaplan-Meier method. Survival was compared with an age-matched population by the log-rank test.

RESULTS

Thirteen patients, eight females, were diagnosed (age +/- standard deviation of 68.3 +/- 10.6 years). All histologic diagnoses were confirmed with immunohistochemical staining results. Mean follow-up was 6.7 years, 8.8 for living patients. One patient had associated extramammary Paget's disease (scrotum). Lesions were located randomly at the dentate line, anal verge, and/or perianal area. Four patients had associated carcinomas; none of them were visceral. Eleven patients underwent local resection, without adjuvant therapy. Almost all recurrences were treated by wider local excision. The five-year recurrence rate was 61 percent. Overall five-year and ten-year survival was 67 percent, no different from the age-matched population (P = 0.546).

CONCLUSIONS

These results do not reflect an aggressive nature of perianal Paget's disease, despite a high rate of local recurrence. Both primary lesions and recurrences are susceptible to treatment by wider local resection. Long-term survival is no different from that of the normal age-matched population.

Detection of colorectal polyps with CT colography: initial assessment of sensitivity and specificity

PURPOSE

To estimate the sensitivity and specificity of computed tomographic (CT) colography in detection of colorectal polyps and to compare these findings with those at axial CT.

MATERIALS AND METHODS

In 70 consecutive patients, CT colography and colonoscopy were performed. Helical axial CT images and CT colographic images (multiplanar two- and three-dimensional endoluminal images) were evaluated separately by two radiologists blinded to results from colonoscopy and other imaging studies. Findings were compared with those at colonoscopy, which was the standard.

RESULTS

The sensitivity and specificity for the two observers with CT colography averaged 75% and 90% in patients with adenomas 10 mm in diameter or larger, 66% and 63% in patients with adenomas 5 mm in diameter or greater, and 45% and 80% for patients with adenomas less than 5 mm in diameter, respectively. Sensitivity and specificity with axial CT were lower than those with CT colography (58% and 74%, respectively) in patients with adenomas 10 mm in diameter or larger.

CONCLUSION

Compared with axial CT, CT colography appears to have superior sensitivity and specificity in detection of clinically important colorectal adenomas. Early performance of CT colography seems promising for detection of colorectal polyps 5 mm and larger.

Effect of the elevated-rim acetabular liner on loosening after total hip arthroplasty

Elevated-rim acetabular liners recently were shown to be associated with improved stability of total hip prostheses in a large clinical series. However, the effect of this design on loosening remains unknown. To address this question, we reviewed the results of 5167 primary and revision total hip arthroplasties that had been performed at our institution from September 1, 1985, through December 31, 1991; 2469 of the acetabular components had an elevated-rim liner (10 degrees of elevation), and 2698 had a standard liner. Five-year follow-up data were available for 1237 hips (174 that had an elevated-rim acetabular liner and 1063 that had a standard acetabular liner). The cumulative probability of revision because of loosening of the implant was estimated as a function of time since the operation with use of the Kaplan-Meier survivorship method. The five-year probability of survival of the acetabular component was 98.8 per cent (95 per cent confidence interval, 97.9 to 99.6 per cent) for the prostheses that had an elevated-rim liner and 98.3 per cent (95 per cent confidence interval, 97.7 to 99.0 per cent) for those that had a standard liner (p = 0.87). The effect of the elevated-rim acetabular liner on the probability of revision because of loosening of the acetabular or the femoral component was analyzed for several subgroups: components inserted with cement, components inserted without cement, primary total hip arthroplasties, revision total hip arthroplasties, male patients, and female patients. With the numbers available, no significant differences were found in the probability of survival of the acetabular or the femoral component in any of the subgroups. Theoretical considerations suggest that the geometric design of the elevated-rim acetabular liner may have biomechanical characteristics that predispose the implant to early loosening. However, our initial review of the results of total hip arthroplasties after a mean follow-up period of five years (range, 0.25 to ten years) failed to demonstrate any difference in the cumulative probability of revision because of loosening of the implant. Continued surveillance is warranted and ongoing.

Complications after concomitant bilateral total knee arthroplasty in elderly patients

OBJECTIVE

To determine the risks associated with performance of bilateral total knee arthroplasty (TKA) in elderly patients.

MATERIAL AND METHODS

Ninety-eight patients with osteoarthritis who were 80 years of age or older and underwent concomitant cemented bilateral TKA were matched (on the basis of gender, surgeon, year of surgical treatment, age, and diagnosis) with 98 patients who underwent cemented unilateral TKA to compare the number and types of complications in these two groups. The groups did not differ in the number and type or severity of premorbid medical conditions, anesthetic risk, and type of anesthesia.

RESULTS

One hundred nineteen postoperative complications occurred in 63 patients in the bilateral TKA group; in contrast, 72 complications occurred in 49 patients in the unilateral TKA group. The difference between the two groups in the total number of complications was significant. Specifically, significant differences between the two groups were noted in the occurrence of cardiovascular and neurologic complications. On paired analysis, congestive heart failure and acute delirium were found to be significantly more frequent in the bilateral TKA group than in the unilateral TKA group. We noted a trend toward an increased mortality rate in the bilateral group (four patients) versus the unilateral group (no deaths).

CONCLUSION

Patients 80 years of age or older who undergo concomitant bilateral TKA are at increased risk for cardiovascular and neurologic complications during the postoperative period in comparison with matched patients who undergo unilateral TKA.

Management of colonoscopic perforations

OBJECTIVE

To document our evolving surgical management of colonoscopic perforation and examine factors crucial to the improvement of patient care.

DESIGN

We conducted a computer-based retrospective analysis of medical records (1980 through 1995).

MATERIAL AND METHODS

Among 57,028 colonoscopic procedures performed, 43 patients (0.075%, or 1 perforation in 1,333 procedures) had a colonic perforation. Two additional patients were treated after colonoscopy performed elsewhere. The outcomes analyzed included surgical morbidity and mortality.

RESULTS

Twenty-six women and 19 men who ranged in age from 28 to 85 years (median, 69) were treated for colonic perforation. More than 80% of perforations occurred during the latter half of the study period because of the increased volume of colonoscopic procedures (8 perforations among 12,581 examinations from 1980 through 1987 versus 35 perforations among 44,447 colonoscopies from 1988 through 1995). Emergency laparotomy was performed in 42 patients (93%). Perforations occurred throughout the colon: right side = 10; transverse = 9; and left side = 23. Three patients without evidence of peritoneal irritation fared well with nonoperative management. Most patients underwent primary repair or limited resection in conjunction with end-to-end anastomosis. In 14 patients (33%), an ostomy was created. One patient underwent laparotomy without further treatment. Intra-abdominal contamination ranged from none (31%) to local soiling (48%) to diffusely feculent (21%). Postoperative complications occurred in 12 patients and were associated with older age (P = 0.01), large perforations (P = 0.03), and prior hospitalization (P = 0.04). No postoperative deaths occurred.

CONCLUSION

Despite a consistently low risk of colonic perforation, the increasing use of colonoscopy in our practice has resulted in an increased number of iatrogenic colonic perforations. In order to minimize morbidity and mortality, prompt operative intervention is the best strategy in most patients. Non-operative management is warranted in carefully selected patients without peritoneal irritation.