Relationship of polypharmacy to HIV RNA suppression in people aged ≥ 50 years living with HIV

OBJECTIVES

People living with HIV (PLWH) aged ≥ 50 years face unique challenges regarding their medication therapies, especially antiretroviral therapy (ART). Use of ARTs, along with medications for comorbidities, may lead to adverse events, drug-drug interactions (DDIs) and poor adherence. The objective of this study was to identify the number of medications above which PLWH aged ≥ 50 years are less likely to be virally suppressed and to describe other associated patient-specific risk factors.

METHODS

This was a cross-sectional study of PLWH aged ≥ 50 years, prescribed ART, and seen at least once in the Northwestern Infectious Disease Center between 1 June 2013 and 31 May 2015. Variables concerning medication use and comorbidities were collected. The primary outcome was the presence of an undetectable plasma HIV RNA level (viral load).

RESULTS

Among the 621 included patients, there was a higher percentage taking ≤ 15 medications with an undetectable plasma HIV RNA (n = 453; 80.6%) vs. patients taking > 15 medications (n = 40; 67.8%; P = 0.03). Taking > 15 medications [odds ratio (OR) 0.49; 95% confidence interval (CI) 0.26-0.96], pulmonary disease (OR 0.54; 95% CI 0.3-0.97) and CD4 T-lymphocyte count < 200 cells/μL (OR 0.39; 95% CI 0.22-0.68) decreased the odds of having an undetectable plasma HIV RNA.

CONCLUSIONS

PLWH taking > 15 medications were less likely to have an undetectable HIV RNA. Further studies are needed to evaluate the impact of overall medication economic burden on clinical outcomes among PLWH ≥ 50 years of age.

Management of fluoroquinolone resistance in Pseudomonas aeruginosa--outcome of monitored use in a referral hospital

We evaluated a strategy designed to improve useful activity of ciprofloxacin against Pseudomonas aeruginosa. Following changes in antimicrobial agent use made by the institutional Pharmacy and Therapeutic Drug Committee, monthly drug usage and microbial susceptibility records from June 1992 through October 1995 were reviewed. From July 1992 through October 1992 (Period 1), ciprofloxacin and ofloxacin usage represented 95 and 5% of total quinolone doses; from December 1992 to March 1993 (Period 2), ciprofloxacin represented 19%; from July 1993 to October 1993 (Period 3), ciprofloxacin usage represented 85%; from July 1994 to October 1994 (Period 4), ciprofloxacin represented 95%; and from July 1995 to October 1995 (Period 5), ciprofloxacin and ofloxacin respectively represented 98 and 2% of total quinolone doses. Comparison of the anti-pseudomonal activity of the two fluoroquinolones to ofloxacin use, ciprofloxacin use and total quinolone use during the entire observational period showed the highest (negative) correlation with ofloxacin use versus ofloxacin activity (y = -15.04x + 1367.99, r2 = 0.06, w = 0.126). Increased use of quinolones plus a change to primarily ofloxacin usage appeared to adversely affect the activity of both ofloxacin and ciprofloxacin against P. aeruginosa.

Enterococcus faecium bacteremia: does vancomycin resistance make a difference?

BACKGROUND

Enterococcus faecium has received increased attention, primarily due to the emergence of vancomycin resistance. The purpose of this investigation was to study the epidemiological characteristics of vancomycin-resistant E faecium (VRE) bacteremia and to determine the clinical impact of vancomycin resistance on the outcome of patients with this infection.

METHODS

We retrospectively analyzed the clinical features and outcome of 53 patients with E faecium bacteremia.

RESULTS

From January 1992 until December 1995, there were 32 episodes of bacteremia caused by vancomycin-susceptible E faecium (VSE) and 21 caused by VRE. An intra-abdominal site was the most common source of bacteremia in both groups. All of the VRE and 78% of VSE bacteremia cases were nosocomially acquired. Previous administration of vancomycin was associated with VRE bacteremia (P<.001), as were indwelling bladder catheters (P=.01). Fifty-nine percent of the patients with VSE bacteremia survived vs 24% with VRE (P=.009), despite similar severity-of-illness scores. In 62% of the patients with VRE sepsis, death was related to the bacteremia (P=.01). Patients infected with VRE had longer hospitalizations than those with VSE (34.8 vs 16.7 days, respectively) (P=.004), were more likely to be on the medical service (P=.03), and on the average, had hospitalization costs of more than $27,000 per episode than did patients with VSE bloodstream infection ($83,897 vs $56,707, respectively) (P=.04).

CONCLUSIONS

Vancomycin-resistant E faecium bacteremia is a complication of prolonged hospitalization in debilitated patients. Vancomycin resistance has a negative impact on survival in patients with E faecium bacteremia and leads to higher health care costs.

Molecular typing for investigating an outbreak of Candida krusei

Invasive infections due to Candida krusei are often observed in immunocompromised patients who have received prior therapy with fluconazole, although infection has also occurred in patients in the absence of this antifungal agent. From August 25 through September 19, 1995, we identified four patients with C. krusei fungemia on our hematology/oncology unit. Molecular typing of all the isolates was performed by restriction endonuclease analysis of genomic DNA using HinfI. A total of 7 patients found to be colonized or infected with C. krusei were matched with 14 controls. There was no difference between the cases and controls with respect to underlying disease, duration of hospitalization, or neutropenia. The numbers of days of hyperalimentation, corticosteroids, and antibiotics were similar between both groups. The mean number of antibiotics was greater in the cases versus controls (5.0 versus 2.5; p = .003). There was no difference with respect to total dose or duration of fluconazole administration. Molecular typing of the isolates revealed that four had identical DNA banding patterns, plus another two that differed by one band and were considered related. Three historical strains were unrelated. In conclusion, this report demonstrates that molecular typing can be used to define clonality and, thereby, support increased infection control practices to eliminate such outbreaks when evidence of clonal spread is present.