Efficacy and safety of recombinant human activated protein C for severe sepsis.

BACKGROUND: Drotrecogin alfa (activated), or recombinant human activated protein C, has antithrombotic, antiinflammatory, and profibrinolytic properties. In a previous study, drotrecogin alfa activated produced dose-dependent reductions in the levels of markers of coagulation and inflammation in patients with severe sepsis. In this phase 3 trial, we assessed whether treatment with drotrecogin alfa activated reduced the rate of death from any cause among patients with severe sepsis. METHODS: We conducted a randomized, double-blind, placebo-controlled, multicenter trial. Patients with systemic inflammation and organ failure due to acute infection were enrolled and assigned to receive an intravenous infusion of either placebo or drotrecogin alfa activated (24 microg per kilogram of body weight per hour) for a total duration of 96 hours. The prospectively defined primary end point was death from any cause and was assessed 28 days after the start of the infusion. Patients were monitored for adverse events; changes in vital signs, laboratory variables, and the results of microbiologic cultures; and the development of neutralizing antibodies against activated protein C. RESULTS: A total of 1690 randomized patients were treated (840 in the placebo group and 850 in the drotrecogin alfa activated group). The mortality rate was 30.8 percent in the placebo group and 24.7 percent in the drotrecogin alfa activated group. On the basis of the prospectively defined primary analysis, treatment with drotrecogin alfa activated was associated with a reduction in the relative risk of death of 19.4 percent (95 percent confidence interval, 6.6 to 30.5) and an absolute reduction in the risk of death of 6.1 percent (P=0.005). The incidence of serious bleeding was higher in the drotrecogin alfa activated group than in the placebo group (3.5 percent vs. 2.0 percent, P=0.06). CONCLUSIONS: Treatment with drotrecogin alfa activated significantly reduces mortality in patients with severe sepsis and may be associated with an increased risk of bleeding.

Causes of death of HIV-infected persons in Ottawa, Ontario, 1984-1995.

BACKGROUND: Acquired immunodeficiency syndrome (AIDS) has become a leading cause of death of young men in the United States. With the introduction of prophylaxes and antiretrovirals for opportunistic infection, there have been significant changes in the clinical history of human immunodeficiency virus (HIV) infection. OBJECTIVE: To determine the cause of death of the patients followed up by our clinic from 1984 to 1995. METHODS: A critical chart review was performed on the records of all patients affiliated with the Ottawa General Hospital HIV/AIDS Clinic, Ottawa, Ontario, who died between 1984 and July 15, 1995. Data regarding the cause of death, last CD4 T-lymphocyte cell count before death, medication use at time of death, and location and year of death were collected. Data were analyzed for 1984 through 1988, 1989 through 1991, and 1992 through 1995, corresponding to the evolution of HIV-related medical care. RESULTS: The median CD4 T-lymphocyte cell count at death had declined. Pneumocystis carinii pneumonia has decreased significantly as cause of death (28.6%-3.8%, P < .001). No other specific attributable terminal illness has decreased in frequency during 11 years. The wasting illnesses, particularly HIV wasting syndrome (3.6%-13.7%, P = .04), and untreatable illnesses have increased in frequency as causes of death. Patients are increasingly likely to die at home (0%-25%, P < .001) and less likely to die in hospital (54%-35%, P < .001). CONCLUSIONS: The HIV-infected persons are dying with more advanced HIV immunosuppression. Advances in P carinii pneumonia prophylaxis and treatment have had a dramatic effect on the cause of death of HIV-infected persons. Improved prophylaxis and treatment for non-P carinii pneumonia opportunistic infections and malignancies and HIV wasting syndrome are required.

Three-year outbreak of pseudobacteremia with Burkholderia cepacia traced to a contaminated blood gas analyzer.

Between November 1990 and June 1993, Burkholderia cepacia was isolated from the blood cultures of 13 neonates born at the Ottawa General Hospital. Eight of the 13 neonates appeared symptomatic, and only 4 were treated with appropriate antimicrobial therapy, but all improved clinically. In August 1993, the blood gas analyzer in the neonatal intensive-care unit was found to be contaminated heavily with B cepacia. Eight available patient isolates were identical to the isolates recovered from the blood gas analyzer by ribotyping analysis. Infection control measures were implemented to prevent future contamination of the analyzer, and no further cases have been identified.

New concepts in the diagnosis and pathogenesis of Trichomonas vaginalis.

Trichomonas vaginalis infection is the most commonly encountered sexually transmitted disease. There is a need for more accurate and rapid laboratory diagnostic methods, leading to better control and treatment strategies. Various virulence factors such as adherence, contact-independent factors, hemolysis and acquisition of host macromolecules have been shown to play a role in the pathogenesis of this infection. Detection of the factors that are only present in the pathogenic isolates of trichomonads will lead to a better understanding of the epidemiology of this pathogen. Culture technique is highly specific compared with microscopic techniques, but it is time consuming. Immunological techniques lack proper correlation with clinical manifestations. The application of monoclonal antibodies, either singly or in a group that recognizes a common antigen, along with methods such as detection of common DNA fragment from clinical specimens, may have a promising future in the laboratory diagnosis of trichomoniasis.

Treatment of oral Candida mucositis infections.

Infections due to Candida spp. are increasing in incidence as the number of immune compromised patients increases. The common presentation of Candida mucositis and oral infections includes atrophic candidiasis, angular cheilitis, leukoplakia and oesophagitis. An increasing spectrum of antifungal agents, including imidazoles, are available for treatment and suppression of this common infection. In chronically immune-compromised patients such as those with severe HIV related immune deficiency, eradication of the infection may not be possible. This requires a stepwise approach to management and may require the use of potent, toxic agents such as amphotericin B to suppress the symptoms and signs of infection sufficiently to provide the patient with symptomatic relief. Resistant organisms are also becoming a greater problem in this patient population.

Analysis of the extracellular proteases of Trichomonas vaginalis.

We have previously isolated two extracellular cysteine proteases (60 and 30 kDa, respectively) from the cell filtrate of an isolate of Trichomonas vaginalis. In this study the clinical presentation of 12 clinical isolates of T. vaginalis was correlated with their protease activity. All 12 isolates produced a 60-kDa protease as demonstrated by immunoblotting. However, only 5 of 12 isolates produced a 30-kDa protease in the extracellular filtrate. Protease activity did not differentiate between isolates obtained from symptomatic versus asymptomatic women. The 60-kDa protease, which breaks down into a 43- and 23-kDa subunit, was detected by immunoblotting with anti-23-kDa cross-reacting rabbit serum in the vaginal washes of 3/3 women with active T. vaginalis infection, 0/1 woman cured of T. vaginalis and 0/2 control women with vaginal candidiasis. These results suggest that the 60-kDa protease is found in all isolates testes in vitro, is present in active disease and may be important in the pathogenesis of T. vaginalis infection.

A Trichomonas vaginalis cDNA with partial protein sequence homology with a Plasmodium falciparum excreted protein ABRA.

We have previously isolated two extracellular cysteine proteases (60 kDa, 30 kDa) from the cell filtrate of an isolate of Trichomonas vaginalis. All isolates tested produced a 60 kDa protease as demonstrated by immunoblot with cross-reacting rabbit serum. A T. vaginalis cDNA library was constructed using lambda gt11. A 760 bp T. vaginalis specific cDNA was sequenced and demonstrates partial protein sequence homology with an extracellular cysteine protease of Plasmodium falciparum. These results are consistent with the hypothesis that this protease may be important in the pathogenesis of T. vaginalis infection.

Fluconazole: a new option in the treatment of Candida mucositis and esophageal candidiasis.

Fluconazole is a new triazole antifungal agent with good activity against Candida and cryptococcal meningitis. It is well-tolerated and effective in immunosuppressed patients with oral-pharyngeal candidiasis. This review outlines the characteristics of fluconazole and discusses its role among the class of antifungal agents.

Interactions between Trichomonas vaginalis and vaginal flora in a mouse model.

To study the role of vaginal flora and pH in the pathogenesis of Trichomonas vaginalis, an intravaginal mouse model of infection was established. By employing this model, the vaginal flora and pH of mice could be monitored for changes caused by the parasite. As a baseline, the endemic vaginal flora of BALB/c mice was examined first and found to consist mainly of Staphylococcus aureus and Enterococcus species (32-76%). Lactobacilli and enteric bacilli were moderate (16-32%) in their frequency of isolation, and the prevalence of both anaerobic species and coagulase-negative staphylococci was low (4-16%). Vaginal pH was recorded at 6.5 +/- 0.3. Estrogenization, which was required for a sustained T. vaginalis infection, did not significantly alter vaginal flora; however, a slight rise in the number of bacterial species isolated per mouse and a drop in vaginal pH (6.2 +/- 0.5) were observed. Trichomonas vaginalis-infected mice did not appear to show significant changes in vaginal flora although vaginal pH was slightly increased. This mouse model could have applications in both immunologic and pathogenic studies of T. vaginalis and, with further modifications, aid in the study of protist-bacterial interactions.

Effect of beta-estradiol on production of the cell-detaching factor of Trichomonas vaginalis.

Despite over 40 years of study, the pathogenetic mechanisms of Trichomonas vaginalis are just starting to be elucidated. We have recently reported that T. vaginalis produces a virulence factor, cell-detaching factor (CDF), that likely causes the cell sloughing seen in clinical disease. This 200-kDa glycoprotein is acid and heat labile and correlates with clinical symptoms. We applied a McCoy cell culture system to study the effects of various concentrations of beta-estradiol (10(-6) to 10(-10) M) on T. vaginalis growth and CDF production. T. vaginalis growth was unaffected by the different concentrations of beta-estradiol studied, in comparison with the growth of control cultures without beta-estradiol. However, beta-estradiol significantly diminished the activity of CDF at all concentrations and did so most profoundly at 10(-7) and 10(-8) M (P less than 0.0001). This suggests that the symptoms of T. vaginalis infection may be influenced by the vaginal concentration of estrogens, and further studies of the interactions between T. vaginalis and estrogens are warranted.

Acute abdomen in the patient with a ventriculoperitoneal shunt.

When patients who have a ventriculoperitoneal shunt present with an acute abdomen, shunt infection may be the cause. The authors relate the cases of three such patients. Two underwent a laparotomy which failed to show any abnormality and which in retrospect might have been avoided. They review the literature and present a systematic approach to the diagnosis and management of this problem. Specific clues from the patient's history, physical examination and further investigation may clarify the diagnosis. When shunt infection cannot be excluded and the clinical setting does not warrant immediate laparotomy, shunt externalization, cerebrospinal fluid culture, empiric antibiotic therapy and close observation of the patient are recommended.

Characterization and purification of extracellular proteases of Trichomonas vaginalis.

Extracellular protease activity was detected in serum-free culture filtrates of Trichomonas vaginalis. The activity was demonstrated by hydrolysis of hide powder azure and possessed the characteristics of cysteine type proteases: inhibition by N-ethyl maleimide, Cu2+, antipain, N-tosyl-L-phenylalanine chloromethyl ketone, N-tosyl-L-lysine chloromethyl ketone, leupeptin, chymostatin, and iodoacetamide, and enhancement by cysteine, EDTA, and dithiothreitol. The activity was optimal at acid pH and the protease was also active on peptide nitroanilides with arginine derivatives. Purification of this activity by ethanol precipitation, ammonium sulfate fractionation, ion exchange chromatography, and gel filtration resulted in the isolation of two proteases estimated by sodium dodecyl sulfate - polyacrylamide gel electrophoresis to have molecular masses of 60 and 30 kilodaltons (kDa), respectively. The larger molecular mass protease broke down during purifications to two subunits of approximately 23 and 43 kDa, as determined by gel electrophoresis. Rabbit sera derived by immunization with the 23-kDa subunit cross-reacted by immunoblot with the 60- and 43-kDa subunits, but not with the 30-kDa protease. These soluble products of T. vaginalis growth could be important pathogenically in establishing T. vaginalis infection in the normally acid (pH less than or equal to 4.5) environment of the vagina.