Catheter complications in AIDS patients treated for cytomegalovirus retinitis

Incidence of and risk factors for bacteraemia in HIV-infected adults in the era of highly active antiretroviral therapy

BACKGROUND

HIV-infected patients have an increased risk for bacteraemia compared with HIV-negative patients. Few data exist on the incidence of and risk factors for bacteraemia across time in the current era of highly active antiretroviral therapy (HAART).

METHODS

We assessed the incidence of bacteraemia among patients followed between 2000 and 2008 at 10 HIV Research Network sites. This large multisite, multistate clinical cohort study collected demographic, clinical and therapeutic data longitudinally. International Statistical Classification of Diseases and Related Health Problems (ICD)-9 codes were examined to identify all cases of in-patient bacteraemia. Logistic regression analysis was used to assess risk factors for bacteraemia and trends over time in the odds of bacteraemia.

RESULTS

A total of 39 318 patients were followed for 146 289 person-years (PY). During the study period, there were 2025 episodes of bacteraemia (incidence 13.8 events/1000 PY). The most common bacteraemia diagnosis was 'bacteraemia, not otherwise specified (NOS)' (51%) followed by Staphylococcus aureus (16%) and Streptococcus species (6.5%). In multivariate analysis, the likelihood of bacteraemia was found to have increased in 2005-2008, compared with 2000. Other factors associated with higher odds of bacteraemia included a history of injection drug use (IDU), age ≥ 50 years, Black race and greater immunosuppression.

CONCLUSIONS

The likelihood of bacteraemia has risen slightly in recent years. Patients who are Black or have a history of IDU are at higher risk. Further research is needed to identify reasons for this increase and to evaluate programmes designed to reduce the bacteraemia risk.

Economic evaluation of treatment administration strategies of ganciclovir for cytomegalovirus retinitis in HIV/AIDS patients in Thailand: a simulation study

BACKGROUND

There are many effective interventions, via various routes (intravenous [IV], oral [OR], intravitreal injection [IVT] and intraocular implantation [IMP]), for treating cytomegalovirus retinitis (CMVR) that have become available. There are large variations in treating CMVR in clinical practice in Thailand.

OBJECTIVE

To evaluate the incremental cost-effectiveness ratio (ICER) of providing (i) IVT, (ii) IV/OR and (iii) IMP ganciclovir to patients with HIV/AIDS and CMVR versus providing no treatment.

DESIGN

A simulation study for which the input parameters were derived from a systematic review of the literature, a hospital-based survey and patient interviews.

SETTING

The analysis assumed a Thai healthcare system perspective. However, the model was run using both societal and healthcare provider perspectives.

RESULTS

Our results suggest that IVT ganciclovir was cost effective and the best option for treating patients with CMVR irrespective of whether patients received antiretroviral treatment (ART). In patients receiving ART, moving from IVT to IV/OR ganciclovir was also likely to be a cost-effective option. Offering IMP ganciclovir was not likely to be cost effective. Providing treatments for patients with bilateral CMVR was more cost effective than providing treatments for those with unilateral CMVR, and offering treatments for patients receiving ART was better value for money than treating patients without ART.

CONCLUSIONS

Our models suggest that IV/OR ganciclovir should be recommended for the treatment of unilateral and bilateral CMVR for patients receiving ART in the Thai healthcare system. IVT ganciclovir may also have a role in the treatment of CMVR patients not receiving ART.

Bacteremias: a leading cause of death

Bloodstream infections (BSIs), recognized to be a major cause of morbidity and mortality globally, are increasing in incidence. The reported rates of crude and attributable mortality vary, possibly due to heterogeneity in patient populations and methodology. Few studies, however, have focused on pathogen-specific attributable mortality. These studies include S. aureus, coagulase-negative staphylococci and enterococcus. Other studies of attributable mortality have been conducted in select populations such as nosocomial and community-acquired cohorts, intensive care units, neutropenic patients, and HIV-positive patients. Regrettably, despite advances in treatment and intensive care facilities, mortality remains high.

Use of filgrastim as adjuvant therapy in patients with AIDS-related cytomegalovirus retinitis

BACKGROUND

Neutropenia in AIDS predisposes to bacterial infection. Granulocyte colony-stimulating factor (filgrastim) can reverse neutropenia.

OBJECTIVE

To determine the effects of filgrastim on bacterial infections, hospitalization, and mortality in patients with cytomegalovirus retinitis and AIDS.

METHODS

Using a person-time analysis, a retrospective cohort study of filgrastim adjuvant therapy in three multicenter clinical trials of anti-cytomegalovirus therapy during the period 1990-1997 measured filgrastim use, bacterial infections, and mortality.

RESULTS

Of 719 patients, 379 patients used filgrastim for 31% of the follow-up time. There was an inverse relationship between the 389 confirmed bacterial infections, including 186 bacteremias, and absolute neutrophil counts. Before adjustment for CD4 T-cells counts and antibiotic/antiretroviral therapy, filgrastim was associated with reduced risk of catheter-related bacteremia [relative risk (RR), 0.52; P = 0.02] and repeat bacterial infection (RR, 0.41; P = < 0.01). After adjustment, the RR of catheter-related bacteremia with filgrastim use was decreased (RRadj, 0.69; P = 0.16) and the RR of repeat bacterial infection with filgrastim use was of marginal significance (RRadj, 0.57; P = 0.07), possibly due to the confounding effect of trimethoprim-sulfamethoxazole on all bacteremia (RRadj, 0.55; P = < 0.01). Unrelated to bacteremia, filgrastim use was associated with a 56% reduction in mortality (P < 0.01).

CONCLUSIONS

There was a large survival benefit associated with filgrastim use in this study but the reasons for this benefit are unclear. Although a reduction in crude risk of some bacterial infections with filgrastim use was detected, after adjustment for potentially confounding factors these risks were smaller and no longer statistically significant.

Catheter-related bloodstream infections in HIV-infected patients

Bloodstream infections (BSI) constitute a significant public health problem and represent an important cause of morbidity and mortality in hospitalized patients, with an approximate incidence of one episode per hundred hospital admissions. Studies on BSI in HIV+ patients have identified central venous catheters (CVC) as a risk factor, with an attributable mortality rate of 10-20%. The long-term CVC-related infection risk appeared to be 5 to 10-fold higher with respect to the infection rates among HIV- patients. CVC associated infection rate ranges from 1.3 to 12 infections per 1,000 catheter-days. Staphylococcus aureus is the most common etiologic agent causative of CVC-related BSI, likely the result of the high skin and nasal carriage of this organism among HIV+ patients, mostly intravenous drug users. Coagulase-negative staphylococci are also frequently identified as cause of CVC-related BSI, likely the result of breaches in infection control measures and in antiseptic technique during CVC management. Treating bacteremia without catheter removal would be optimal, but the reported efficacy of systemic antibiotic therapy alone is only 25-32%. Conversely, recent studies have shown that, using an antibiotic-lock procedure, up to 90% of HIV-infected and uninfected patients achieved complete eradication of catheter-related BSIs without catheter removal. Clinical trials using new materials such as covalently linked heparin on the CVC surface, electrically charged CVC, novel topical agents that interfere with bacterial colonization, antiadhesin molecules and agents that block the gene expression involved in the biofilm formation, are all needed to reduce the high catheter-related infection risk among HIV+ patients.

The ganciclovir implant plus oral ganciclovir versus parenteral cidofovir for the treatment of cytomegalovirus retinitis in patients with acquired immunodeficiency syndrome: The Ganciclovir Cidofovir Cytomegalovirus Retinitis Trial

PURPOSE

To compare the regimen of the ganciclovir implant plus oral ganciclovir to one of intravenous cidofovir for the treatment of cytomegalovirus retinitis.

METHODS

Sixty-one patients with acquired immunodeficiency syndrome and cytomegalovirus retinitis were randomized either to the regimen of the ganciclovir implant plus oral ganciclovir, 1 gm three times daily, or intravenous cidofovir, 5 mg/kg once weekly for two doses, followed by 5 mg/kg every other week.

RESULTS

Mortality was similar between the two treatment groups. Mortality rates were 0.41 per person-year in patients assigned to the ganciclovir regimen and 0.49 per person-year in patients assigned to cidofovir (P =.59). Ocular outcomes were similar between the two groups. Retinitis progression occurred at a rate of 0.67 per person-year in the ganciclovir group and 0.71 per person-year in the cidofovir group (P =.72). A loss of visual acuity of 15 letters or more occurred at a rate of 0.78 per person-year in the ganciclovir group and 0.47 per person-year in the cidofovir group (P =.28). The rate of loss of visual field was 7 degrees per month in the ganciclovir group and 2 degrees per month in the cidofovir group (P =.048). Vitreous hemorrhage was more common in the ganciclovir implant group (0.13 per person-year) than in the cidofovir group (no cases, P =.014), whereas uveitis appeared to be more common in the cidofovir group (0.35 per person-year) than in the ganciclovir group (0.09 per person-year, P =.066). Nephrotoxicity (serum creatinine 1.6 mg/dL or greater) occurred at a rate of 0.18 per person-year in the ganciclovir group and 0.48 per person-year in the cidofovir group (P =.10).

CONCLUSIONS

Although the small number of patients in this study limits definitive interpretation, these data suggest that in the era of highly active antiretroviral therapy, the regimens of the ganciclovir implant plus oral ganciclovir and of intravenous cidofovir are similar for controlling cytomegalovirus retinitis and preventing visual loss but have different side effects.

Incremental cost effectiveness of prophylaxis for cytomegalovirus disease in patients with AIDS

Cytomegalovirus (CMV) disease, an opportunistic complication in patients with AIDS, causes substantial morbidity and has high treatment costs. Although prevention of this disease is highly desirable, incremental cost-effectiveness estimates for proposed prophylactic strategies in the era prior to the availability of highly active antiretroviral therapy (HAART) were unfavourable relative to other specific antimicrobial prophylactic strategies in patients with AIDS. With the availability of HAART, several inputs upon which previous estimates of the incremental cost-effectiveness ratio for anti-CMV prophylaxis were based probably changed substantially. To assess the incremental cost effectiveness of prophylaxis in the HAART era, data are needed on visual outcomes and utility for patients with CMV retinitis and AIDS, on better strategies for identifying subpopulations at high risk for CMV disease and on the prophylactic efficacy of valganciclovir. Cost-effectiveness analysis could potentially contribute by exploring thresholds of population risk, prophylactic effectiveness, and drug pricing in order to identify conditions under which prophylaxis for CMV disease in patients with AIDS could potentially become cost effective.

Complications of indwelling catheters in cystic fibrosis: a 10-year review

STUDY OBJECTIVE

Patients with cystic fibrosis (CF) frequently require recurrent courses of IV antibiotics to treat acute exacerbations of their pulmonary disease. Over time, CF patients often lose peripheral access, and indwelling central venous catheters are placed. We attempted to determine the type and incidence of catheter complications so that CF patients could be fully informed of the risks prior to placement of these catheters.

DESIGN

The charts of all CF patients who attended the Adult Cystic Fibrosis Clinic of the University of Washington Medical Center from January 1989 through December 1998 were reviewed. Demographic information was obtained along with the type and duration of catheter, type and number of complications, and the use of anticoagulant medication.

MEASUREMENTS AND RESULTS

Of the 218 CF patients who attended the clinic, 65 patients (30%) had indwelling catheters in place at some time during the study period. A total of 87 catheters were placed into these 65 patients. The total number of catheter-days for first indwelling catheters was 68,220. The total number of catheter-days for all catheters was 75,660 (210 catheter-years). Thirty-five catheter-related complications were identified, occurring in 26 patients. Complications included thrombosis (n = 14), infections (n = 9), mechanical problems (n = 6), pneumothorax (n = 3), superior vena cava syndrome/stenosis (n = 2), and air embolism (n = 1), for an overall complication rate of 0. 463/1,000 catheter-days.

CONCLUSION

We conclude that indwelling catheters are relatively safe in patients with CF. Good infection control policies appear to prevent most infectious complications. The most common complication is that of thrombosis, which may be recurrent in some patients. Consideration should be given to prophylactic warfarin therapy despite the potential risk of significant hemoptysis in this patient population.

CMV retinitis in the era of HAART

Since 1996, major advances in the treatment of AIDS have markedly changed the incidence and the prognosis of CMV retinitis. Highly active antiretroviral therapy (HAART) is a combination of nucleoside reverse transcriptase inhibitors and protease inhibitors. This new therapeutic strategy is highly efficient in reducing the HIV viral load and increasing CD(4)+ T-lymphocyte count. These biological effects are associated with an improvement of immune functions. Clinically, the completely quiescent CMV retinitis and the unusual prolonged relapse-free interval suggest a certain restoration of immune functions, making possible the discontinuation of maintenance therapy. For most authors, the decision to stop anti-CMV maintenance therapy is based on a CD4+ cell count >100 cells/microl with a low HIV viral load for at least four months. The improvement of CMV retinitis on HAART may also be associated with an intraocular inflammation called immune recovery vitritis. For some patients, this vitritis may be associated cystoid macular edema and an epiretinal membrane responsible for visual loss.