Clarithromycin or rifabutin alone or in combination for primary prophylaxis of Mycobacterium avium complex disease in patients with AIDS: A randomized, double-blind, placebo-controlled trial. The AIDS Clinical Trials Group 196/Terry Beirn Community Programs for Clinical Research on AIDS 009 Protocol Team.

The efficacy and safety of clarithromycin and rifabutin alone and in combination for prevention of Mycobacterium avium complex (MAC) disease were compared in 1178 patients with AIDS who had < or =100 CD4 T cells/microL in a randomized, double-blind, placebo-controlled trial. MAC disease occurred in 9%, 15%, and 7% of those randomized to clarithromycin or rifabutin alone or in combination, respectively; time-adjusted event rates per 100 patient-years (95% confidence interval [CI]) were 6.3 (4.2-8.3), 10.5 (7.8-13.2), and 4. 7 (2.9-6.5). Risk of MAC disease was reduced by 44% with clarithromycin (risk ratio [RR], 0.56; 95% CI, 0.37-0.84; P=.005) and by 57% with combination therapy (RR, 0.43; 95% CI, 0.27-0.69; P=. 0003), versus rifabutin. Combination therapy was not more effective than clarithromycin (RR, 0.79; 95% CI, 0.48-1.31; P=.36). Of those in whom clarithromycin or combination therapy failed, 29% and 27% of MAC isolates, respectively, were resistant to clarithromycin. There were no survival differences. Clarithromycin and combination therapy were more effective than rifabutin for prevention of MAC disease, but combination therapy was associated with more adverse effects (31%; P<.001).

Pilot study of topical trifluridine for the treatment of acyclovir-resistant mucocutaneous herpes simplex disease in patients with AIDS (ACTG 172). AIDS Clinical Trials Group.

SUMMARY: Twenty-six AIDS patients were enrolled in an open label pilot study to evaluate the efficacy and toxicity of topical 1 percent ophthalmic trifluridine solution for the treatment of chronic mucocutaneous herpes simplex virus disease unresponsive to at least 10 days of acyclovir therapy. Susceptibility testing to acyclovir, trifluridine, and foscarnet was determined by plaque reduction assay. Twenty-four patients were evaluable for efficacy and 25 for toxicity analyses. Seven patients (29 percent) had complete healing of lesions. The overall estimated median time to complete healing was 7.1 weeks. An additional seven patients had > or = 50 percent reduction in lesion area. The overall estimated median time to 50 percent healing was 2.4 weeks. Ten (42 percent) patients discontinued treatment for reasons other than primary treatment failure and seven (29 percent) for failure to respond to therapy. Baseline patient characteristics associated with greater reduction in lesion area included higher Karnofsky score (p = 0.05), fewer lesions (p = 0.07), smaller lesion area (p = 0.11), and trifluridine susceptibility (p = 0.07). Eight (33 percent) patients developed new lesions outside of the treatment area while on study, reflecting the local nature of this therapy. No dose-limiting toxicity attributable to trifluridine was reported. Given the limited options for the treatment of acyclovir-resistant herpes simplex disease, topical trifluridine may be a useful alternative in selected patients.

Response of CD4 lymphocytes and clinical consequences of treatment using ddI or ddC in patients with advanced HIV infection.

The value of CD4 lymphocyte counts as a surrogate marker in persons with advanced human immunodeficiency virus infection during antiretroviral treatment was assessed using longitudinal models and data from the Terry Beirn Community Programs for Clinical Research on AIDS didanosine/zalcitabine trial of 467 HIV-infected patients. Patients with AIDS or two CD4 counts of < or = 300 who fulfilled specific criteria for zidovudine intolerance or failure were randomized to receive either 500 mg didanosine (ddl) daily or 2.25 mg zalcitabine (ddC) per day. Absolute CD4 counts were recorded at study entry and at as many as four visits. Patients were followed for clinical disease progression and survival. At 2 months, the difference in mean CD4 count from baseline was +15.4 cells/mm3 in the ddI group but -1.3 cells/mm3 in the ddC group. Patients assigned to ddI had a greater chance of a CD4 response at 2 months than those on ddC, yet only those in the ddC group with a response showed significant improvement in progression of disease or survival compared with ddC nonresponders, ddI responders, and ddI nonresponders (p = 0.03). We conclude that a CD4 response does not necessarily correlate with improved outcome and is therefore not a useful surrogate marker in these patients.

High-dose pentoxifylline in patients with AIDS: inhibition of tumor necrosis factor production. National Institute of Allergy and Infectious Diseases AIDS Clinical Trials Group.

Tumor necrosis factor-alpha (TNF) may activate human immunodeficiency virus (HIV), antagonize zidovudine activity, and contribute to AIDS wasting syndrome. Pentoxifylline decreases TNF production. In cell culture, pentoxifylline decreases HIV replication and gene expression. Since an AIDS Clinical Trial Group study suggested that pentoxifylline (400 mg thrice daily) is safe in AIDS patients and decreases TNF mRNA levels in peripheral blood mononuclear cells (PBMC), a second cohort received 800 mg thrice daily for 8 weeks. During treatment, the median decrease in TNF production by PBMC cultured with 0.1 microgram/mL lipopolysaccharide (LPS) was 40%. The median change in TNF mRNA was a 34% decrease. Pentoxifylline did not affect HIV levels as detected by quantitative microculture or serum p24 antigen measurements, nor did it alter zidovudine pharmacokinetics. The most common toxicity was gastrointestinal. Pentoxifylline at dosages of less than thrice-daily 800 mg is well tolerated and may decrease TNF mRNA levels and LPS-induced TNF production.

Two-stage tuberculin skin testing in individuals with human immunodeficiency virus infection. Community Programs for Clinical Research on AIDS.

In this study we estimated occurrence of the booster effect in a population infected with the human immunodeficiency virus (HIV) and assessed the relation between the booster effect, T-lymphocyte CD4 cell counts, tuberculosis risk categories, and HIV exposure categories. Patients were recruited from 13 participating sites of the Terry Beirn Community Programs for Clinical Research on AIDS (CPCRA). A two-stage tuberculin skin test was applied to 709 HIV-infected patients using the Mantoux method. An induration reading < 5 mm on the first test and > or = 5 on the second skin test defined the booster effect. Overall, 18 patients, or 2.7% (95% confidence interval, 1.6 to 4.2) experienced the booster effect. Boosted responses were seen in eight (2.1%) anergic patients, six (4.5%) nonanergic patients, and four (2.5%) with anergy status unknown. Boosting was noted in 1 of the 131 women enrolled. Age, race, CD4 cell count, injection drug use, anergy status, tuberculosis risk categories, and HIV exposure categories were not predictive of boosting. The booster effect occurs in a small percentage of HIV-infected patients tested, thus identifying small numbers of patients with latent tuberculosis infection. The two-stage procedure is probably of limited value in the diagnosis of latent tuberculosis in HIV-infected persons.

Clarithromycin therapy for bacteremic Mycobacterium avium complex disease. A randomized, double-blind, dose-ranging study in patients with AIDS. AIDS Clinical Trials Group Protocol 157 Study Team.

OBJECTIVE: To determine the antimicrobial activity and tolerability of clarithromycin for treating bacteremic Mycobacterium avium complex disease in patients with the acquired immunodeficiency syndrome (AIDS). DESIGN: A randomized, double-blind, dose-ranging study. SETTING: Outpatient clinics. PATIENTS: 154 patients with human immunodeficiency virus (HIV) infection and blood cultures positive for M. avium complex who had symptomatic disease. INTERVENTIONS: Random assignment to clarithromycin at dosages of 500 mg, 1000 mg, or 2000 mg twice daily for 12 weeks. MAIN OUTCOME MEASURE: Median number of colony-forming units of M. avium complex per milliliter of blood. RESULTS: Clarithromycin decreased mycobacterial CFUs from 2.7 to 2.8 log 10/mL of blood at baseline to less than 0 log 10/mL during follow-up (P < 0.0001). After 2 weeks, patients receiving 500 mg twice daily were less likely to be culture negative than were patients receiving 1000 or 2000 mg twice daily (11% compared with 33% or 29%; P = 0.08). At 6 weeks, the median number of CFUs of M. avium complex/mL of blood was 0 or 1 for all three groups. Clarithromycin-resistant isolates of M. avium complex developed in 46% of patients at a median of 16 weeks. Median survival was longer in patients assigned to 500 mg twice daily (median, 249 days) than in patients assigned to 1000 mg or 2000 mg. Death in the first 12 weeks was lowest in the 500-mg group (P = 0.007). CONCLUSIONS: Clarithromycin therapy acutely decreased M. avium complex bacteremia in patients with HIV infection by more than 99%. Clarithromycin, 500 mg twice daily, was well tolerated and associated with better survival. Emergence of clarithromycin-resistant organisms was an important problem.

Survival and disease progression according to gender of patients with HIV infection. The Terry Beirn Community Programs for Clinical Research on AIDS.

OBJECTIVE: To compare disease progression and mortality between women and men infected with human immunodeficiency virus (HIV). DESIGN: Multicenter cohort. SETTING: Seventeen community-based centers participating in the Terry Beirn Community Programs for Clinical Research on AIDS (CPCRA). PATIENTS: A total of 768 women and 3779 men enrolled in one or more of 11 protocols between September 7, 1990, and September 30, 1993. MAIN OUTCOME MEASURES: Survival and opportunistic events. RESULTS: The median CD4+ cell count at enrollment into the cohort was 0.240 x 10(9)/L (240/microL) for women and 0.137 x 10(9)/L for men (P < .001). Compared with men, women were younger (36 vs 38 years), more likely to be African American or Hispanic (78% vs 44%), and more likely to have reported a history of injection drug use (49% vs 27%). Women had been followed up for a median of 14.5 months and men for 15.5 months. The adjusted relative risk (RR) for death among women compared with men was 1.33 (95% confidence interval [CI], 1.06 to 1.67; P = .01) and for disease progression (including death) was 0.97 (95% CI, 0.82 to 1.15; P = .72). Women were at increased risk for bacterial pneumonia (RR, 1.38; 95% CI, 1.05 to 1.92) and at reduced risk for the development of Kaposi's sarcoma (RR, 0.16; 95% CI, 0.04 to 0.65) and oral hairy leukoplakia (RR, 0.54; 95% CI, 0.31 to 0.94). The increased risk of death and bacterial pneumonia for women compared with men was primarily evident among those with a history of injection drug use (RR, 1.68 for death, 95% CI, 1.20 to 2.35, P = .003; RR, 1.53 for bacterial pneumonia, 95% CI, 1.03 to 2.29, P = .04). Among patients without a history of disease progression at entry, death was the first event reported for more women than men (27.5% vs 12.2%). CONCLUSIONS: Compared with men, HIV-infected women in the CPCRA were at increased risk of death but not disease progression. Risks of most incident opportunistic diseases were similar for women and men; however, women were at an increased risk of bacterial pneumonia. These findings may reflect differential access to health care and standard treatments or different socioeconomic status and social support for women compared with men.

Randomized phase I trial of two different combination foscarnet and ganciclovir chronic maintenance therapy regimens for AIDS patients with cytomegalovirus retinitis: AIDS clinical Trials Group Protocol 151.

AIDS patients with newly diagnosed cytomegalovirus (CMV) retinitis who had just completed a 14-day course of ganciclovir induction therapy were randomly assigned to an alternating or concurrent combination regimen of chronic ganciclovir-foscarnet therapy for CMV retinitis. Each regimen used lower weekly cumulative doses of each drug than standard monotherapy maintenance treatment regimens. Dose-limiting toxicity attributable to foscarnet occurred in only 2 (7%) of 29 evaluatable patients, and no patients experienced dose-limiting nephrotoxicity. Although absolute neutrophil counts < 500 cells/microL occurred in 11 (38%) of 29 patients, all who subsequently used adjunctive granulocyte colony-stimulating factor had severe neutropenia prevented. Severe toxicity of any type and neutropenia, in particular, occurred significantly more frequently in patients assigned to the concurrent treatment regimen. CMV was isolated from none of 21 patients who had urine cultured and from only 1 of 24 who had blood cultured while being treated during the study (median evaluation, 12 weeks). This suggests that combination therapy provides better in vivo antiviral activity in suppressing CMV replication than previously reported with monotherapy regimens.

A comparative trial of didanosine or zalcitabine after treatment with zidovudine in patients with human immunodeficiency virus infection. The Terry Beirn Community Programs for Clinical Research on AIDS.

BACKGROUND: Both didanosine and zalcitabine are commonly used to treat patients with human immunodeficiency virus (HIV) infection who cannot tolerate zidovudine treatment or who have had disease progression despite it. The relative efficacy and safety of these second-line therapies are not well defined. METHODS: In this multicenter, open-label trial we randomly assigned 467 patients who previously received zidovudine and had 300 or fewer CD4 cells per cubic millimeter or a diagnosis of the acquired immunodeficiency syndrome (AIDS) to treatment with either didanosine (500 mg per day) or zalcitabine (2.25 mg per day). RESULTS: After a median follow-up of 16 months, disease progression or death occurred in 157 of 230 patients assigned to didanosine and 152 of 237 patients assigned to zalcitabine, for a relative risk of 0.93 for the zalcitabine group as compared with the didanosine group (P = 0.56), which decreased to 0.84 (P = 0.15) after adjustment for the CD4 count, Karnofsky score, and presence of AIDS at base line. There were 100 deaths in the didanosine group and 88 in the zalcitabine group, for a relative risk of 0.78 (P = 0.09) and an adjusted relative risk of 0.63 (P = 0.003). A majority of patients in each group (66 percent) had at least one adverse event during treatment (153 patients taking didanosine and 157 taking zalcitabine). Peripheral neuropathy and stomatitis occurred more often with zalcitabine and diarrhea and abdominal pain more frequently with didanosine. CONCLUSIONS: For patients with HIV infection who have not responded to treatment with zidovudine, zalcitabine is at least as efficacious as didanosine in delaying disease progression and death.

Pentoxifylline decreases tumor necrosis factor expression and serum triglycerides in people with AIDS. NIAID AIDS Clinical Trials Group.

Tumor necrosis factor-alpha (TNF)-cachectin increases the expression of the human immunodeficiency virus (HIV), reverses the therapeutic efficacy of zidovudine (ZDV), and may contribute to the wasting syndrome. Pentoxifylline (Trental) decreases TNF activity; in cell culture, it decreases HIV replication and down-regulates expression of the HIV long terminal repeat (LTR). Therefore, pentoxifylline was administered to 25 patients with advanced AIDS in this AIDS Clinical Trial Group study (ACTG #160), the goal of which was to investigate the ability of the drug to decrease TNF expression and HIV replication in this patient population. One patient discontinued drug treatment because of toxicity. Data were analyzed on the 17 patients who completed the 8-week study treatment with pentoxifylline, 400 mg, thrice daily. The median pretreatment CD4+ lymphocyte count was 32 cells/mm3. Fasting serum triglycerides, which have previously been shown to correlate with levels of interferon-alpha and/or TNF, fell on average by 66 mg/dl (p = 0.06). TNF mRNA levels in peripheral blood mononuclear cells fell in 10 of 16 patients (p = 0.02). HIV load decreased and increased significantly in four and one patients, respectively, but did not change in the group as a whole. This study demonstrates the safety of pentoxifylline in AIDS patients and its ability to decrease triglycerides and TNF mRNA levels.

Methicillin-resistant Staphylococcus aureus: a consensus review of the microbiology, pathogenesis, and epidemiology with implications for prevention and management.

Methicillin-resistant Staphylococcus aureus (MRSA) has become a major nosocomial pathogen in community hospitals, long-term-care facilities, and tertiary care hospitals. The basic mechanism of resistance is alteration in penicillin-binding proteins of the organism. Methods for isolation by culture and typing of the organism are reviewed. MRSA colonization precedes infection. A major reservoir is the anterior nares. MRSA is usually introduced into an institution by a colonized or infected patient or health care worker. The principal mode of transmission is via the transiently colonized hands of hospital personnel. Indications for antibiotic therapy for eradication of colonization and treatment of infection are reviewed. Infection control guidelines and discharge policy are presented in detail for acute-care hospitals, intensive care and burn units, outpatient settings, and long-term-care facilities. Recommendations for handling an outbreak, surveillance, and culturing of patients are presented based on the known epidemiology.

Prospective observational study of Klebsiella bacteremia in 230 patients: outcome for antibiotic combinations versus monotherapy.

Combination antimicrobial agent therapy has been advocated for treatment of gram-negative bacteremia, including that caused by Klebsiella spp. We performed a prospective, observational, 10-hospital collaborative study to evaluate the efficacy of antibiotic combination therapy versus that of monotherapy for 230 consecutive patients with Klebsiella bacteremia. The species involved were K. pneumoniae (82%), K. oxytoca (15%), and K. ozaenae (0.4%). Of the bacteremias, 26% were polymicrobial in nature. A total of 53% of cases were nosocomial infections. The most common portals were the urinary tract (28%), biliary tract (12%), lung (10%), and abdomen (9%). Some 49 and 51% of the patients had received monotherapy and antibiotic combination therapy (beta-lactam plus aminoglycoside), respectively; 14-day mortalities in the two groups were 20 and 18%, respectively. However, for the subgroup of patients who experienced hypotension within 72 h prior to or on the day of the positive blood culture, those patients who received combination therapy experienced significantly lower mortality (24%) than did those who received monotherapy (50%). We conclude that monotherapy with an antibiotic that is active in vitro against Klebsiella (beta-lactam or aminoglycoside) is sufficient therapy for less severely ill patients (immunocompetent, urinary tract portal, mentally alert, normal vital signs). On the other hand, for severely ill patients who experience hypotension, antibiotic combination therapy with a beta-lactam and an aminoglycoside agent is preferred.

Addition of rifampin to combination antibiotic therapy for Pseudomonas aeruginosa bacteremia: prospective trial using the Zelen protocol.

A multicenter, prospective randomized trial was conducted to determine if the addition of rifampin to a combination therapy of an antipseudomonal beta-lactam agent and aminoglycoside improves the outcome of patients with Pseudomonas aeruginosa bacteremia. The Zelen protocol for randomized-consent design was used. Consent was sought only from patients randomized to the experimental therapy (rifampin+). If the experimental therapy was refused, the patient would then receive the standard combination therapy (control); however, when outcome was evaluated, all patients randomized to the rifampin+ group, including those that declined rifampin, were compared with the control group. One hundred twenty-one consecutive hospitalized patients with positive blood cultures for P. aeruginosa were enrolled. Entry was stratified for prior use of empiric antipseudomonal antibiotics, neutropenia, severity of illness, and presence of pneumonia. Fifty-eight patients were randomized to receive rifampin (600 mg orally every 8 h for the first 72 h and then every 12 h for a total of 10 days) plus a beta-lactam agent plus an aminoglycoside. Sixty-three received the standard therapy of a beta-lactam plus an aminoglycoside agent (control). Bacteriologic cure occurred significantly more frequently in patients randomized to the rifampin+ regimen. Breakthrough or relapsing bacteremias occurred in 2% of the three-drug (rifampin+) group, compared with 14% for the two-drug (standard therapy) group. Despite this favorable trend in bacteriological response, no significant differences in survival were seen for the two treatment groups. Rifamycin derivatives warrant further clinical study as antipseudomonal agents. The Zelen protocol appears well suited for comparative trials of antimicrobial agents.

CD4+ lymphocyte cell enumeration for prediction of clinical course of human immunodeficiency virus disease: a review.

Over the last 10 years the appreciation of the full breadth of the spectrum of human immunodeficiency virus (HIV) infection has gradually increased; it is now known that AIDS represents merely the end stage of this progressive infectious process. The surrogate marker that most closely correlates with the stage of HIV infection is the CD4+, or T helper, cell count. Because this count is relied on in making important therapeutic decisions, it is of paramount importance that clinicians be cognizant of and fully understand the multiple factors that can influence this parameter: the variability of the count from day to day and from morning to night, the influence of intercurrent viral infections, the influence of drugs. In this AIDS Commentary, Sten H. Vermund and his colleagues at the National Institutes of Health discuss these issues and put the CD4+ cell count into a lucid and practical clinical perspective.

Klebsiella pneumonia in the modern era: clinicoradiographic correlations.

A classic clinical and radiographic picture of Klebsiella pneumonia has emerged in the literature. Patients are typically male, older than 48 years, and have a history of chronic alcoholism. The majority of these pneumonias are community acquired. Bulging interlobar fissures and cavitation are radiographic findings said to be distinctive for Klebsiella pneumonia. We prospectively studied 15 cases of bacteremically proven Klebsiella pneumonia and found clinical and radiographic features strikingly different from those described in the literature. Immunosuppression (from corticosteroids, cytotoxic chemotherapy, neutropenia, hematologic malignancy, and transplantation) now rivals alcoholism as the primary risk factor. Cases tended to be nosocomial rather than community acquired. Neither bulging interlobar fissure nor cavitation was seen in any case. The right upper lobe was involved in 11 of our 15 cases. Pneumonia due to Klebsiella oxytoca was more likely to be isolated from patients with bilateral infiltrates, while Klebsiella pneumoniae was more likely in patients with unilateral infiltrates.

Pseudomonas aeruginosa bacteremia in patients undergoing liver transplantation: an emerging problem.

In our institution, Pseudomonas aeruginosa bacteremia appeared to occur with increasing frequency in patients undergoing liver transplantation. We thus conducted a prospective study to define risk factors and outcome in these patients. Over a 19-month period 6% of liver transplants were followed by Pseudomonas bacteremia. The mean age was 46 years (range, 24 to 67 years). The interval between transplantation and onset of bacteremia was 3 to 372 days (mean, 80). The incidence of Pseudomonas bacteremia in liver transplants was three times that of other transplants (heart, lung, kidney). Ninety one percent of infections were nosocomial. Polymicrobial bacteremia occurred in 30% of episodes. The portal of entry was respiratory in 30%, abdominal in 35%, and biliary in 13%. Four patients had recurrent Pseudomonas bacteremia: liver abscess (1), biliary obstruction (2), subhepatic abscess (1). Survival at 14 days was 70%. Survival rates were significantly lower for patients with hypotension, on mechanical ventilators, and increasing severity of illness (p less than 0.05). Survival was higher when bacteremia occurred within the first 30 days after transplantation compared to after 30 days. A large number (43.4%) of Pseudomonas bacteremias occurred after transplant surgery of biliary tract manipulation, while the patient was receiving a prophylactic regimen of cefotaxime and ampicillin. P. aeruginosa is an important pathogen in the liver transplant recipient; prevention may be possible for a subgroup of patients with the use of prophylactic antibiotics with activity against P. aeruginosa.

Multiple-dose pharmacokinetics of concurrent oral ciprofloxacin and rifampin therapy in elderly patients.

The purpose of this clinical study was to investigate the influence of concomitant drug therapy with ciprofloxacin and rifampin on the individual pharmacokinetic profile of each agent in elderly patients. Twelve nursing home patients (age, 74 +/- 7 years), colonized with methicillin-resistant Staphylococcus aureus, were randomized to receive 14-day therapy with oral ciprofloxacin (750 mg every 12 h) (group A; n = 6) or ciprofloxacin (750 mg every 12 h) and oral rifampin (300 mg every 12 h) (group B; n = 6). Serial blood samples were obtained from 0 to 12 h following ciprofloxacin doses 1 and 13 and from 0 to 36 h after the last ciprofloxacin dose. No significant differences (P greater than 0.05) were found between or within groups in any pharmacokinetic parameter. The mean ciprofloxacin oral clearance values were 0.35 +/- 0.06, 0.41 +/- 0.15, and 0.38 +/- 0.11 liter/h per kg for doses 1, 13, and 28, respectively, in group A patients. The mean oral clearance values in group B patients for the respective doses were 0.53 +/- 0.36, 0.32 +/- 0.13, and 0.36 +/- 0.17 liter/h per kg. Likewise, no significant differences (P greater than 0.05) in rifampin pharmacokinetic parameters were found when compared with historical controls. These data suggest that ciprofloxacin and rifampin may be given concomitantly in standard clinical dosing regimens. The combination results in therapeutic levels of both drugs and appears to be safe for administration to elderly nursing home patients.