Partner symptom accommodation in generalized anxiety disorder: a preliminary examination of correlates with symptoms and cognitive behavioural therapy outcome

BACKGROUND

Symptom accommodation is suggested to maintain anxiety pathology and interfere with treatment effectiveness for anxiety and related disorders. However, little is known about symptom accommodation in generalized anxiety disorder (GAD).

AIM

This study investigated the associations between romantic partner symptom accommodation, GAD symptoms, intolerance of uncertainty (IU), relationship satisfaction, and cognitive behavioural therapy (CBT) outcomes from the perspective of the person with GAD.

METHOD

One hundred and twelve people with GAD participated in group CBT and completed measures at pre- and post-treatment.

RESULTS

All participants endorsed that their partner engaged in symptom accommodation to some extent, and the most commonly endorsed type was providing reassurance. Greater self-reported partner symptom accommodation was associated with greater GAD symptoms, chronic worry severity, IU, and relationship satisfaction at baseline. Partner symptom accommodation was found to significantly decrease over treatment; however, less improvement in symptom accommodation from pre- to post-treatment was associated with worse treatment outcomes.

DISCUSSION

This study is the first to show that partner symptom accommodation is prevalent in adults with GAD and to elucidate the presentation and frequency of behaviours. The findings provide preliminary evidence that targeting partner symptom accommodation in treatment may improve CBT outcomes.

Effectiveness and predictors of group cognitive behaviour therapy outcome for generalised anxiety disorder in an out-patient hospital setting

BACKGROUND

Cognitive behavioural therapy (CBT) is an empirically supported treatment for generalized anxiety disorder (GAD). Little is known about the effectiveness of CBT for GAD in real-world treatment settings.

AIM

This study investigated the effectiveness of group CBT and predictors of treatment response in an out-patient hospital clinic.

METHOD

Participants (n = 386) with GAD participated in 12 sessions of group CBT at an out-patient clinic. Of those who provided at least partial data (n = 326), 84.5% completed treatment. Most questionnaires were completed at pre- and post-treatment; worry severity was assessed weekly.

RESULTS

Group CBT led to improvements in chronic worry (d = -0.91, n = 118), depressive symptoms (d = -1.22, n = 172), GAD symptom severity (d = -0.65, n = 171), intolerance of uncertainty (IU; d = -0.46, n = 174) and level of functional impairment (d = -0.35, n = 169). Greater pre-treatment GAD symptom severity (d = -0.17, n = 293), chronic worry (d = -0.20, n = 185), functional impairment (d = -0.12, n = 292), and number of comorbid diagnoses (d = -0.13, n = 299) predicted greater improvement in past week worry over treatment. Biological sex, age, depression symptom severity, number of treatment sessions attended, and IU did not predict change in past week worry over time.

DISCUSSION

These findings provide support for the effectiveness of group CBT for GAD and suggest the outcomes are robust and are either not impacted or are slightly positively impacted by several demographic and clinical factors.

Optimizing screening for depression, anxiety disorders, and post-traumatic stress disorder in inpatient addiction treatment: A preliminary investigation

OBJECTIVE

Substance use disorders (SUD) are frequently comorbid with other psychiatric conditions, but a comprehensive diagnostic assessment is often not feasible clinically. Efficient psychometrically-validated screening tools exist for commonly comorbid conditions, but cutoff accuracies have typically not been evaluated in addiction treatment settings. This study examined the performance of several widely-used screening measures in relation to diagnostic status from a clinical interview to identify and validate cutoff scores in an inpatient SUD treatment setting.

METHOD

Participants were 99 patients in a large residential SUD treatment program in Ontario, Canada. Participants completed a screening battery, including the Patient Health Questionnaire - 9 (PHQ-9), Generalized Anxiety Disorder - 7 (GAD-7), and Post-Traumatic Stress Disorder Checklist-5 (PCL-5), and underwent a semi-structured diagnostic clinical interview. Receiver operating characteristic curves were used to determine optimal cutoff scores on the screening tool against the interview-based diagnosis.

RESULTS

Area under the curve (AUC) was statistically significant for all screens and were as follows: PHQ-9 = 0.70 (95% CI = 0.59-0.80), GAD-7 = 0.74 (95% CI = 0.63-0.84), and PCL-5 = 0.79 (95% CI = 0.66-0.91). The optimal accuracy cutoff scores based on sensitivity and specificity were: PHQ-9 ≥ 16, GAD-7 ≥ 9, the PCL-5 ≥ 42.

CONCLUSIONS

In general, the candidate screeners performed acceptably in this population. However, the optimal cutoff scores were notably higher than existing guidelines for depression and PTSD, potentially due to the general elevations in negative affectivity among individuals initiating SUD treatment. Further validation of these cutoff values is warranted.

PUBLIC HEALTH SIGNIFICANCE

This study provides modified screening cutoff scores for major depression, anxiety disorders, and post-traumatic stress disorder in addiction treatment settings.

Perioperative psychotherapy for persistent post-surgical pain and physical impairment: a meta-analysis of randomised trials

BACKGROUND

Persistent post-surgical pain affects 10-80% of individuals after common operations, and is more common among patients with psychological factors such as depression, anxiety, or catastrophising.

METHODS

We conducted a systematic review and meta-analysis of randomised, controlled trials to evaluate the efficacy of perioperative psychotherapy for persistent post-surgical pain and physical impairment. Paired independent reviewers identified studies, extracted data, and assessed risk of bias. The Grading of Recommendations, Assessment, Development and Evaluation system was used to assess the quality of evidence.

RESULTS

Our search of five electronic databases, up to September 1, 2016, found 15 trials (2220 patients) that were eligible for review. For both persistent post-surgical pain and physical impairment, perioperative education was ineffective, while active psychotherapy suggested a benefit (test of interaction P=0.01 for both outcomes). Moderate quality evidence showed that active perioperative psychotherapy (cognitive-behaviour therapy, relaxation therapy, or both) significantly reduced persistent post-surgical pain [weighted mean difference (WMD) -1.06 cm on a 10 cm visual analogue scale for pain, 95% confidence interval (CI) -1.56 to -0.55 cm; risk difference (RD) for achieving no more than mild pain (≤3 cm) 14%, 95% CI 8-21%] and physical impairment [WMD -9.87% on the 0-100% Oswestry Disability Index, 95% CI -13.42 to -6.32%, RD for achieving no more than mild disability (≤20%) 21%, 95% CI 13-29%].

CONCLUSIONS

Perioperative cognitive behavioural therapy and relaxation therapy are effective for reducing persistent pain and physical impairment after surgery. Future studies should explore targeted psychotherapy for surgical patients at higher risk for poor outcome.

CLINICAL TRIAL REGISTRATION

PROSPERO CRD42016047335.

Effect of distraction and coping style on in vivo exposure for specific phobia of spiders

Recent studies have generated mixed findings regarding the effects of distraction on exposure-based treatments. Results have also been inconsistent regarding the effects of monitoring and blunting coping styles on outcome. The present study attempted to integrate these two areas of research. We hypothesized that the effect of distraction on treatment outcome might depend on coping style. Specifically, we predicted that for blunters (i.e.. individuals who tend to avoid threat-related information), distraction would interfere with the effects of exposure. However, we predicted that distraction might benefit monitors (i.e., individuals who tend to seek out threat-related information). Sixty individuals with a specific phobia of spiders underwent a single, two-hour session of exposure treatment. During the first hour, half of the participants were distracted by listening to an audiotape and the other half underwent exposure without distraction. In the second hour, all participants underwent focused exposure. Based on measures of heart rate, subjective fear, and behavioral testing, participants improved after one hour of treatment, and improved further during the second hour. However, neither distraction, coping style, nor their interaction had a significant effect on outcome. The present study provides support for the benefits of behavioral treatment for specific phobias. However, our hypotheses regarding distraction and coping style were not confirmed.

Enhancement of human osteoblast proliferation and phenotypic expression when cultured in human serum

Traditionally, culture medium is supplemented with foetal bovine serum (FBS). However, in cultures of osteoblasts intended for human re-implantation, such serum presents potential risks of foreign protein contamination and transmission of viral or prion-related material, if used. We cultured human osteoblasts from 16 patients in 10% autologous human serum, 10% pooled human serum, 10% FBS or 2% Ultroser G. Non-synthetic sera were tested in both heat-treated and non-heat-treated forms. We determined cell growth and osteoblast phenotype. Cell proliferation in all types of human serum was significantly greater than in FBS. This was most marked in heat-treated autologous human serum. Cells cultured in Ultroser G had less proliferation than all other groups. The phenotypic tests showed that cells cultured in human and foetal bovine serum displayed an osteoblast phenotype, with greater protein expression in cells cultured in human serum. We conclude that culture of human osteoblasts in autologous human serum enhances cell proliferation, while maintaining an osteoblast phenotype. These findings have implications for the use of cultured osteoblasts in self-cell therapy. Human osteoblast growth is supported by autologous human serum, which allows re-implantation of cultured cells, while avoiding the risk of foreign protein carry-over with enhancement of cell proliferation.

Weight-related and shape-related self-evaluation in eating-disordered and non-eating-disordered women

OBJECTIVE

Weight- and shape-related self-evaluation refers to the process whereby an individual determines her self-worth based on an evaluation of her body weight and shape. This is a hallmark feature of both anorexia and bulimia nervosa, as specified in the 4th ed. of the Diagnostic and Statistical Manual of Mental Disorders. The purpose of this study was to further our understanding of weight-related self-evaluation in eating-disordered women.

METHOD

Eating-disordered patients, restrained eaters, and unrestrained eaters completed an experimenter-designed questionnaire that examines different dimensions of weight-related self-evaluation (i.e., the Multidimensional Weight-Related Self-Evaluation Inventory).

RESULTS

Results revealed that weight-related self-evaluation is a feature shared, to some extent, by both eating-disordered patients and restrained eaters. However, eating-disordered patients extend weight-related self-evaluation to include more domains of self-esteem than did restrained eaters.

DISCUSSION

These findings support a multidimensional approach to weight-related self-evaluation and further our understanding of the process of weight-related self-evaluation in eating-disordered patients.

Eating disorders, dieting, and the accuracy of self-reported weight

OBJECTIVE

This study investigated the accuracy of self-reported weight and height in individuals with an eating disorder (i.e., anorexia nervosa [AN] and bulimia nervosa [BN]) and in individuals without an eating disorder (i.e., dieters and nondieters).

METHOD

Self-reported and measured weights and heights were obtained from the eating disorder sample (n = 81) and the college student sample (n = 163) and were compared within and between the groups.

RESULTS

Eating disorder patients were extremely accurate at self-reporting their weight. However, there was a significant difference in accuracy between AN and BN patients. AN patients slightly overreported their weight, whereas BN patients slightly underreported their weight. Both dieters and nondieters significantly underreported their weight. However, dieters significantly underreported their weight to a greater degree than did the nondieters.

DISCUSSION

The implications of these subgroup differences and their specificity to weight reporting are discussed with reference to the accuracy of self-reported height.

Randomized comparison trial of teicoplanin i.v., teicoplanin i.m., and cefazolin therapy for skin and soft tissue infections caused by gram-positive bacteria

Teicoplanin, a glycopeptide antibiotic chemically related to the vancomycin-ristocetin group of antibiotics, has potent activity against aerobic and anaerobic gram-positive bacteria. In this study, we examined the efficacy and safety of teicoplanin for parenteral treatment of skin and soft tissue infections caused by gram-positive bacteria. Ninety-six hospitalized adults with moderate to severe skin and soft tissue infections were randomized to receive either teicoplanin intravenously (i.v.) once a day, teicoplanin intramuscularly (i.m.) once a day, or cefazolin i.v. every 8 hours. We evaluated patients' clinical and microbiologic status and assessed clinical and laboratory adverse events. Of 76 clinically assessable patients, 26 of 26 (100%) given teicoplanin i.v., 21 of 22 (95%) given teicoplanin i.m., and 26 of 28 (93%) given cefazolin showed improvement or cure. Of 60 microbiologically assessable patients, 22 of 22 (100%) given teicoplanin i.v., 16 of 18 (89%) given teicoplanin i.m, and 18 of 20 (90%) given cefazolin were cured. Of 96 patients assessable for adverse events, 7 of 34 (21%) given teicoplanin i.v., 4 of 31 (13%) give teicoplanin i.m., and 1 of 31 (3%) given cefazolin had adverse events. In this study, once daily teicoplanin appeared to be safe and effective therapy for skin and soft tissue infections.

Molecular typing of ampicillin-resistant, non-beta-lactamase-producing Enterococcus faecium isolates from diverse geographic areas

Molecular typing methods were compared by using 66 ampicillin-resistant, non-beta-lactamase-producing Enterococcus faecium clinical isolates from diverse geographic areas. Whole-plasmid analysis, restriction enzyme analysis of plasmid DNA with EcoRI and HindIII, and contour-clamped homogeneous electric field electrophoresis with digestion by SmaI and ApaI were performed on all isolates. Whole-plasmid analysis identified 47 different groups. Restriction enzyme analysis of plasmid DNA identified 50 groups when EcoRI was used and 51 groups when HindIII was used. Results with EcoRI and HindIII differed in 9 of 66 isolates. Grouping results with whole-plasmid analysis differed from results of restriction enzyme analysis of plasmid DNA (combining EcoRI and HindIII) in 20 of 66 isolates. Contour-clamped homogeneous electric field electrophoresis identified 46 groups when SmaI was used and 44 groups when ApaI was used. Results with SmaI and ApaI differed in 3 of 66 isolates. Grouping results with contour-clamped homogeneous electric field electrophoresis (combining SmaI and ApaI) differed from results of restriction enzyme analysis of plasmid DNA (combining EcoRI and HindIII) in 17 of 66 isolates. The combined use of whole-plasmid analysis, restriction enzyme analysis of plasmid DNA with two enzymes, and contour-clamped homogeneous electric field electrophoresis with two restriction enzymes should be considered when E. faecium is typed for epidemiologic investigation.

Nosocomial acquisition of beta-lactamase--negative, ampicillin-resistant enterococcus

BACKGROUND

A recent prospective study at the Department of Veterans Affairs Medical Center, Martinez, Calif, revealed that 9% of enterococcal clinical isolates were ampicillin resistant. We prospectively studied 100 patients hospitalized in one general medicine ward and in the medical intensive care unit to study determinants of acquisition of ampicillin-resistant enterococcus.

METHODS

Rectal swabs and urine cultures were obtained from patients within 72 hours of admission to the study ward and twice weekly until discharge from the ward or the intensive care unit. Cultures were obtained from the hands of personnel and from environmental surfaces in the general medical ward and the intensive care unit. Ampicillin-resistant enterococcal isolates were examined for molecular relatedness by plasmid DNA analysis.

RESULTS

The cultures from 23 patients yielded ampicillin-resistant enterococci. The rectal swabs yielded ampicillin-resistant enterococci before the urine cultures did except in one patient whose urine and rectal cultures were both positive on the same day. Acquisition of ampicillin-resistant enterococci was significantly associated with previous antimicrobial agents, Foley catheterization, and being bedridden. Resistant enterococci were not isolated from hospital personnel or environmental surfaces. Plasmid analysis by gel electrophoresis demonstrated nine strains, two of which predominated. Rectal and urine isolates from the same patient had identical plasmid electrophoresis patterns.

CONCLUSIONS

We conclude that ampicillin-resistant enterococci are common in the rectal flora, can spread to the urinary system, are associated with patient characteristics that predipose to nosocomial infection, and may become an emerging clinical problem.

Endovascular infections caused by enterococci highly resistant to ampicillin

Enterococci frequently cause endocarditis and are the most common gram-positive isolates in polymicrobial bacteremia. We report three cases of polymicrobial endovascular infections at a single institution during a 12-month period; the enterococcal isolates were highly resistant to penicillins. These cases comprised 18% of all enterococcal endovascular isolates during the same 12-month period. Previous use of antibiotics, presence of endovascular catheters, and nosocomial acquisition of the organism occurred in all three cases. Clinicians should be aware of enterococcal resistance to penicillins and should exercise care in designing appropriate regimens for serious enterococcal infections.

Ampicillin-resistant Enterococcus raffinosus in an acute-care hospital: case-control study and antimicrobial susceptibilities

A prospective study identified 9 (32%) of 28 ampicillin-resistant (MIC greater than or equal to 16 micrograms/ml) enterococcus isolates as Enterococcus raffinosus. A case-control study found no significant differences with respect to underlying diseases, catheterization, or surgery between patients with ampicillin-resistant E. raffinosus and those with ampicillin-susceptible Enterococcus spp. Prior treatment with antibiotics and prolonged hospitalization were more frequent among patients with ampicillin-resistant E. raffinosus. Patients with the same strain (determined by plasmid analysis) were frequently hospitalized concurrently.

Ceftibuten versus cefaclor for the treatment of bronchitis

Ceftibuten is an oral third generation cephalosporin with potent antimicrobial activity against Enterobacteriaceae, beta-lactamase positive Haemophilus influenzae, Moraxella catarrhalis, Neisseria meningitidis, Neisseria gonorrheae, penicillin-susceptible pneumococci, and beta-hemolytic streptococci. To study the efficacy and safety of ceftibuten for treatment of bronchitis, 58 patients were randomized to therapy with either ceftibuten 400 mg once a day or cefaclor 250 mg every 8 h at a ratio of two to one. Of 45 clinically evaluable patients, 28 (87.5%) of the 32 ceftibuten patients and 12 (92.3%) of the 13 cefaclor patients were clinically improved or cured. Of 33 microbiologically evaluable patients, 21 (87.5%) of the 24 ceftibuten patients and eight (80%) of the ten cefaclor patients were cured. Of 56 patients evaluable for adverse effects, three (7.9%) of the 38 ceftibuten patients and one (5.6%) of the 18 cefaclor patients had adverse reactions. In this small study, once-daily ceftibuten appeared as safe and as effective as cefaclor for the treatment of bronchitis.

Intravenous or intramuscular teicoplanin once daily for skin and soft-tissue infections

Teicoplanin is a new glycopeptide antibiotic with potent activity against gram-positive bacteria and pharmacokinetics that allow once daily administration. To study the efficacy and safety of teicoplanin for skin and soft-tissue infections, 75 patients received teicoplanin intravenously (38) or intramuscularly (37, of which 16 were outpatients). Of 62 clinically evaluable patients, 97 percent of teicoplanin iv and 93 percent of teicoplanin im patients were cured or improved. All teicoplanin iv patients and 64 percent of teicoplanin im patients were cured microbiologically at 24-48 hours posttherapy. Persistence of organisms frequently was associated with skin ulcers or abscess cavities and usually had no bearing on clinical outcome. Possible adverse clinical and laboratory reactions caused by teicoplanin occurred in 4 of 38 teicoplanin iv patients (11 percent) and in 8 of 37 teicoplanin im patients (22 percent). Reactions were mild and resolved with discontinuation of teicoplanin in most cases. In this study, teicoplanin appeared to be safe, efficacious, and convenient for both hospital staff and patients, and potentially cost-effective for the treatment of skin and soft-tissue infections. In particular, teicoplanin appears to be appropriate for outpatient parenteral therapy.

Endogenous interferon-gamma, macrophage activation, and murine host defense against acute infection with Trypanosoma cruzi

Parenteral interferon-gamma (IFN-gamma) activates murine macrophages to inhibit Trypanosoma cruzi multiplication and diminishes parasitemia and mortality in acute infection. To investigate the role of endogenous IFN-gamma in acute infection, monoclonal antibody to IFN-gamma was injected intraperitoneally into mice. The 6250 neutralizing units given 24 and 96 h after infection reproducibly increased mortality (P less than .05). Histology sections showed markedly more nests of T. cruzi in treated mice. BALB/c, Swiss Webster, C57Bl/6, and C3H/HEN mice were susceptible to the effects of anti-IFN-gamma. Peritoneal macrophages from mice 4 days after infection and a single dose of 6250 units of anti-IFN-gamma had significantly reduced ability to inhibit T. cruzi multiplication. Multiple doses of anti-IFN-gamma delayed but did not prevent macrophage activation. These results indicate the critical role of endogenous IFN-gamma for macrophage activation and host defense against acute T. cruzi infection in mice.

In vitro model of attachment of Giardia intestinalis trophozoites to IEC-6 cells, an intestinal cell line

Attachment of giardias to intestinal cells has been difficult to study because of a lack of a convenient in vitro model. We developed an assay for attachment of radiolabeled trophozoites to IEC-6 cells that can be done in microtiter trays. Attachment was confirmed by scanning and transmission electron microscopy. Trophozoites remained attached to the IEC-6 cells for 24 h with little evidence of damage to the IEC-6 cells. Preincubation of trophozoites with cytochalasins A, B, and D reduced attachment to approximately 20% of that of controls, whereas colchicine had no effect. Chelation of divalent cations with EDTA and EGTA [ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid] reduced attachment to 24 and 26% of control values, respectively, and incubation at 4 degrees C reduced attachment to 7% of the value for controls incubated at 37 degrees C. Glutaraldehyde fixation of trophozoites or IEC-6 cells resulted in significantly diminished attachment to the live substrate (17 and 40% of control values, respectively). Coincubation of IEC-6 cells and trophozoites on a rotary shaker resulted in detachment of 40% of trophozoites, but EDTA, EGTA, glutaraldehyde fixation of trophozoites, and low temperature diminished attachment markedly and significantly. Similar results were obtained in selected experiments with three strains of giardia.

Atypical presentations of Pneumocystis carinii pneumonia in patients receiving inhaled pentamidine prophylaxis

Inhaled pentamidine is used commonly to prevent Pneumocystis carinii pneumonia (PCP) in patients with advanced human immunodeficiency virus infection. Case reports indicate that PCP can recur in patients who receive inhaled pentamidine and that clinical features may be atypical. To determine the magnitude of this problem, we reviewed retrospectively the medical records of patients with proven PCP during a 30-month period at two hospitals. Four (31 percent) of 13 patients with previous PCP who received inhaled pentamidine prophylaxis had recurrent P carinii infection, including one patient with widely metastatic extrapulmonary disease. Chest roentgenographic findings included cavities, pneumothoraces, bilateral and upper lobe interstitial infiltrates, and pleural effusion. False-negative bronchoalveolar lavage and induced sputum examinations were frequent. We conclude that recurrent PCP in patients maintained on a regimen of inhaled pentamidine prophylaxis occurs frequently, causes chest roentgenographic abnormalities other than interstitial infiltrates, and may be difficult to diagnose. Clinicians who choose to use this effective and convenient mode of prophylaxis should be aware of the problems attendant to its use.

Current diagnosis and management of toxoplasmosis in cancer patients

Toxoplasmosis should be considered as a potential pathogen in cancer patients who have clinical syndromes, especially lymphadenopathy, for which the cause is not clear. Patients with reticuloendothelial malignancies or solid cancers treated with systemic chemotherapy or with progressive disease appear to be at particular risk for life-threatening toxoplasmosis. There has also been an explosion in the number of cases of toxoplasmic encephalitis in patients infected with HIV. Diagnosis rests on demonstration of trophozoites in tissue or body fluids, demonstration of characteristic serologic test results, and, in cases of lymphadenopathy, characteristic histologic features.

Ampicillin-resistant enterococcal species in an acute-care hospital

A prospective review of all enterococcal isolates for 13 months showed that 9.0% were resistant to ampicillin (MIC, greater than or equal to 16 micrograms/ml; zone diameter, less than 15 mm), as determined by the Vitek system, disk diffusion, microdilution MIC testing, and macrodilution MIC testing. All were beta-lactamase negative. A total of 19 and 3 resistant isolates were from urine and intravascular sites, respectively. Ampicillin-resistant enterococci appear to be a growing clinical problem.

Failure of Trypanosoma cruzi to trigger the respiratory burst of activated macrophages. Mechanism for immune evasion and importance of oxygen-independent killing

Activated macrophages are thought to kill Trypanosoma cruzi, which lack catalase, by the generation of hydrogen peroxide. We investigated triggering of the respiratory burst of activated macrophages induced by phagocytosis of virulent T. cruzi, bloodform trypomastigotes, amastigotes obtained from spleens, and tissue culture organisms; and of relatively nonvirulent epimastigotes. All stages of T. cruzi prompted the release of less than 10% of hydrogen peroxide released by activated macrophages when stimulated with PMA or Candida. Superoxide anion production was not stimulated by PMA or Candida in activated macrophages nor was there a significant qualitative reduction of nitroblue tetrazolium induced by ingestion of virulent T. cruzi. Opsonization of T. cruzi with specific antibody did not promote the release of hydrogen peroxide or the reduction of nitroblue tetrazolium. Similar results were observed with activated spleen macrophages. Incubation of activated macrophages with catalase, catalase and superoxide dismutase, sodium benzoate with or without catalase, and respiratory burst-exhausting PMA failed to inhibit the killing of T. cruzi in vitro. These results indicate that 1) virulent opsonized or unopsonized T. cruzi do not trigger a respiratory burst by activated macrophages and 2) oxygen-independent killing of T. cruzi is of prime importance.

Failure of Trypanosoma cruzi to trigger the respiratory burst of activated macrophages. Mechanism for immune evasion and importance of oxygen-independent killing

Activated macrophages are thought to kill Trypanosoma cruzi, which lack catalase, by the generation of hydrogen peroxide. We investigated triggering of the respiratory burst of activated macrophages induced by phagocytosis of virulent T. cruzi, bloodform trypomastigotes, amastigotes obtained from spleens, and tissue culture organisms; and of relatively nonvirulent epimastigotes. All stages of T. cruzi prompted the release of less than 10% of hydrogen peroxide released by activated macrophages when stimulated with PMA or Candida. Superoxide anion production was not stimulated by PMA or Candida in activated macrophages nor was there a significant qualitative reduction of nitroblue tetrazolium induced by ingestion of virulent T. cruzi. Opsonization of T. cruzi with specific antibody did not promote the release of hydrogen peroxide or the reduction of nitroblue tetrazolium. Similar results were observed with activated spleen macrophages. Incubation of activated macrophages with catalase, catalase and superoxide dismutase, sodium benzoate with or without catalase, and respiratory burst-exhausting PMA failed to inhibit the killing of T. cruzi in vitro. These results indicate that 1) virulent opsonized or unopsonized T. cruzi do not trigger a respiratory burst by activated macrophages and 2) oxygen-independent killing of T. cruzi is of prime importance.

Treatment of recurrent urinary tract infection with norfloxacin versus trimethoprim-sulfamethoxazole

Norfloxacin, a broad-spectrum antimicrobial analog of nalidixic acid, was evaluated by comparing it to trimethoprim-sulfamethoxazole in 93 office patients with recurrent urinary tract infections. In this prospective randomized study, norfloxacin and trimethoprim-sulfamethoxazole were given on the same dosage schedule with the former drug given as a 400-mg tablet twice daily and the latter drug given as a double strength tablet twice daily. Overall, 50 patients received norfloxacin and 43 patients received trimethoprim-sulfamethoxazole with a cure rate of 96 percent and 79 percent, respectively. Whether a patient had one infection or multiple previous infections, norfloxacin appeared to be superior to trimethoprim-sulfamethoxazole. Only minor side effects were noted in either group, and no patient withdrew from this study as a direct result of these side effects. Minor complaints of nausea, dizziness, and headache were found in the norfloxacin group (24%) and in the trimethoprim-sulfamethoxazole group (16%). Both agents are effective in treating urinary tract infections but norfloxacin is superior to trimethoprim-sulfamethoxazole in patients with either recurrent complicated infections or one previous uncomplicated urinary tract infection.

Current recommendations and future prospects in the treatment of toxoplasmosis

Toxoplasma infection is highly prevalent throughout the world and causes disease in diverse populations. Effective treatment regimens are available for each clinical entity of toxoplasma, but problems of incomplete clinical efficacy, drug potency, drug safety, and length of treatment remain. No well-controlled clinical trials in humans have been performed to evaluate the efficacy and safety of treatment. Primary treatment of toxoplasmosis is with the synergistic combination of pyrimethamine and sulphonamide. This is considered the treatment of choice for severe disease, disease in immunocompromised patients, and congenital toxoplasmosis. Spiramycin, a macrolide antibiotic, is frequently used alone or alternately with pyrimethamine and sulphonamide for pregnant women with the acute acquired infection to prevent congenital toxoplasmosis. Clindamycin is used frequently to treat acute flares of toxoplasmic chorioretinitis and as second-line therapy for toxoplasmic encephalitis in patients with the acquired immunodeficiency syndrome (AIDS). Inadequacies in the treatment of toxoplasmosis in immunosuppressed patients, exemplified by experience with AIDS patients, should provide the impetus for well-designed trials to find and evaluate more potent and better-tolerated agents. Classes of new drugs that have been investigated and show some promise include: (a) macrolides (roxithromycin, azithromycin); (b) folic acid antagonists (piritrexim and trimetrexate), and (c) purine analogues (arprinocid). Immunomodulators have attracted interest, and interferon-gamma alone and in combination with roxithromycin is effective in murine models. Interleukin-2 is also effective in the murine model.

Open lung biopsy in patients with non-Hodgkin's lymphoma and pulmonary infiltrates

Patients with non-Hodgkin's lymphoma (NHL) are at increased risk for pulmonary infection with opportunistic pathogens associated with diminished cell mediated immunity. Open lung biopsy (OLB) frequently is recommended for diagnosis of pulmonary infiltrates in patients with NHL, but its usefulness for patient management and outcome has not been evaluated for patients with NHL. We reviewed the results of 20 consecutive OLB in 19 patients with previously diagnosed non-Hodgkin's lymphoma at Stanford University Medical Center during a nine-year period. Fifteen patients had known active lymphoma at time of OLB, and no patient had granulocytopenia. Ten of the 20 OLBs yielded specific diagnoses. A greater proportion of patients with stage I or II disease had specific diagnoses than patients with more advanced NHL. Five of 14 patients considered to have had a life threatening illness at the time of OLB had specific diagnoses from OLB vs five of six patients considered clinically stable. Chest roentgenograms that had discrete masses or nodules correlated with ability to establish a specific diagnosis by OLB. For patients in whom the results of OLB were nonspecific, management appeared unaffected by the OLB. The OLB in NHL appeared most useful for detecting recurrent NHL in clinically stable patients with discrete nodules or masses on chest roentgenogram. Pneumocystis pneumonia was the only infection identified by OLB.

Perinephric abscess in renal transplant recipients: report of seven cases and review

The experience of four kidney transplantation programs from 1975 to 1986 was reviewed to determine the prevalence and clinical characteristics of perinephric abscess in renal transplant recipients. Seven cases were found, with a prevalence of 0.3% in 1,945 patients seen over a 12-year period in one program. Current prevalence appears markedly less than in older studies. Despite immunosuppression, signs and symptoms of perinephric abscess were prominent and included fever, flank and abdominal pain and tenderness, and abdominal mass. Perinephric abscesses were diagnosed 2 weeks to 52 months after transplantation and were associated with lymphoceles in two patients. Abdominal ultrasound and computed tomography were useful in diagnosis. Staphylococci (36%) and aerobic gram-negative rods (32%) were the most common pathogens in our seven patients combined with patients identified in a review of the English-language literature. Also of note were the presence of anaerobes (28%) and Candida albicans (4%). Therapy was successful in all of our seven patients.

Open lung biopsy in patients with Hodgkin's disease and pulmonary infiltrates

Although open lung biopsy (OLB) is frequently employed for diagnosis of pulmonary lesions in patients with Hodgkin's disease, the actual efficacy of the procedure in establishing a diagnosis in these patients, and its effect on their treatment and clinical outcome, have not been evaluated. We reviewed the results of OLB in 41 patients with previously diagnosed Hodgkin's disease (17 with stage II disease, 10 with stage III, and 14 with stage IV) who had pulmonary opacification on chest roentgenogram. Nineteen (46%) diagnoses were specific and 22 nonspecific. The most common specific diagnosis was Hodgkin's disease (12 patients); the others were Pneumocystis carinii pneumonia (3), solitary fungal granuloma (2), cytomegalovirus pneumonia (1), and primary lung adenocarcinoma (1). Specific diagnoses were made in 11 (69%) of 16 patients with discrete nodules or masses but in only eight (32%) of the 25 patients with non-nodular radiographic opacification. Eleven (58%) of 19 patients who were asymptomatic or had had symptoms for longer than 4 wk had specific diagnoses, compared to one of six patients (17%) symptomatic for 1 wk or less. Survival of hospitalization correlated more with stage of Hodgkin's disease than with specific diagnosis. However, treatment was changed after biopsy in 22 (54%) of the patients. The results suggest that OLB can be helpful in the management of patients with Hodgkin's disease and pulmonary infiltrates, both in establishing a diagnosis and in assisting the patients' management. OLB appears to be more helpful in patients with Hodgkin's disease than in patients with acute nonlymphocytic leukemia or the acquired immunodeficiency syndrome and pulmonary infiltrates.

Trypanosoma cruzi: explant organ cultures from mice with chronic Chagas' disease

Explants of 13 different organs obtained from C3H/HEN, Swiss-Webster, and C57Bl/6 mice chronically infected with Trypanosoma cruzi (Y strain) were cocultivated with mouse embryo fibroblasts to determine the organs that contain T. cruzi during the chronic infection. Explant cultures frequently yielded T. cruzi as late as 12 months after infection. Spleen and skeletal muscle were most frequently positive; heart cultures were rarely positive in any mouse strain. C3H/HEN mice had significantly more cultures positive than Swiss-Webster mice, as expected from relative susceptibility of C3H/HEN mice to acute infection. In contrast, C57Bl/6 mice, relatively resistant to acute infection, had significantly more cultures positive at 12 months of infection than Swiss-Webster mice. Also, C57Bl/6 mice had a significant increase in the number of positive cultures at 12 months of infection compared to 6 months of infection. These results show that organisms can be recovered routinely from some tissues during the chronic infection, that murine susceptibility to infection should differentiate between acute and chronic infection, and that C57Bl/6 mice may lose control of infection during the chronic infection.

Comparison of once-daily cephalosporin regimens for community-acquired lower respiratory tract infections in patients with chronic lung disease

The efficacy of cefonicid and of ceftriaxone, administered once daily for the treatment of lower respiratory tract bacterial infections (pneumonia or bronchitis), was evaluated and compared in 118 patients with chronic lung disease. The patients were randomly assigned to receive 1 gm of either drug, intravenously or intramuscularly, daily for three to 11 days (mean, seven days). Pathogenic bacteria were isolated from sputum in 59% of patients; Haemophilus influenzae and Streptococcus pneumoniae predominated. Clinical cure or improvement was noted in 95% and 93% of patients treated with cefonicid and ceftriaxone, respectively, and bacteriologic cure or improvement in 69% and 81% (the differences were not significant). Side effects were infrequent and similar in the two treatment groups, except that diarrhea was more common in the ceftriaxone group (11%, versus 4.4% in the cefonicid group). It is concluded that patients with chronic lung disease who experience acute exacerbations associated with infection caused by H influenzae or S pneumoniae, or other susceptible organisms, can be effectively treated with once-daily administration of either cefonicid or ceftriaxone.

Primaquine is lethal for intracellular but not extracellular Trypanosoma cruzi

Primaquine has been used to treat Chagas' disease in humans and has been reported to be active against extracellular Trypanosoma cruzi. Experiments were designed to evaluate the relative activity of primaquine against extra- and intracellular T. cruzi and to determine if primaquine might be combined advantageously with ketoconazole. Primaquine at 0.5 micrograms/ml significantly inhibited T. cruzi replication in infected mouse peritoneal macrophages and also effectively treated infected L929 cells. To examine the effect of primaquine on extracellular organisms, tissue culture T. cruzi were incubated with primaquine for different periods of time and then used to infect macrophages. Incubation with 10 micrograms/ml for 14 hr but not 8 hr significantly inhibited but did not eradicate replication. Incubation of spleen amastigotes or blood trypomastigotes for 2 hr with 10 micrograms/ml did not inhibit replication. Incubation of extracellular tissue culture T. cruzi with primaquine for 2 hr did not potentiate the activity of ketoconazole against intracellular organisms. The combination of primaquine and ketoconazole administered to acutely infected mice significantly decreased parasitemias in comparison to treatment with primaquine or ketoconazole alone. Thus primaquine acts primarily on intracellular rather than extracellular T. cruzi. Primaquine and ketoconazole appear to have additive activity in vivo.

Diagnosis of pulmonary infections in immunocompromised patients

In an immunocompromised patient with fever and pulmonary infiltrates, it frequently is difficult to decide which invasive procedure, if any, to use to obtain a definitive diagnosis. Because most lung infiltrates in immunosuppressed patients are caused by bacteria and sputum usually is readily available for examination, empiric therapy with potent, safe, broad spectrum, antibacterial drugs often is successful. Invasive procedures that prove a diagnosis may result in substantive changes in therapy in perhaps as few as 10 to 20 per cent of patients, and the procedure itself may harm the patient. In a unique study in which patients with acute pneumonitis without neutropenia were randomized to either empiric antibiotic treatment or treatment based on results of open lung biopsy, patients with open lung biopsy had a worse outcome, possibly related to morbidity of open lung biopsy. Furthermore, no diagnoses were provided by open lung biopsy that were not treated by the empiric regimen. A missed treatable disease may be tragic, however. A thoughtful clinician must evaluate each patient with careful consideration of the history in light of the underlying disease and its treatment, rapidity of clinical course, physical examination, and laboratory data, particularly the chest radiograph, sputum examination, and bleeding parameters. Fiberoptic bronchoscopy with washings and brushings is very safe; the addition of transbronchial biopsy adds diagnostic power at the price of some complications. Bronchoalveolar lavage is a very promising technique that probably will find widespread use. However, none of the foregoing techniques is completely sensitive. When no diagnosis is established and bronchoscopy studies are negative, open lung biopsy must be considered, especially when the chest radiograph or computed tomography scan suggests focal disease or lymphadenopathy. Needle aspiration can be used, particularly if local experience is favorable and lung disease is peripheral. When evaluating a procedure, local experience must be considered rather than reliance on published diagnostic yields and complication rates. New diagnostic and therapeutic developments may change decision analysis in the near future. At present, cultures for viruses and fungi and serologic techniques have little application at most medical centers, and decisions on data from invasive procedures pivot on interpretation of histology and smears. Development of assays for antigen (for example, Aspergillus) and rapid culture techniques (for example, cytomegalovirus and the shell vial method), coupled with new, effective antimicrobials, may demand maximum effort for a definitive diagnosis in every patient.

Hospital survey of antimicrobial prophylaxis to prevent endocarditis in patients with prosthetic heart valves

The American Heart Association (AHA) has published guidelines for use of prophylactic antibiotics to prevent bacterial endocarditis, but few data are available about physician compliance with these guidelines. A retrospective review was conducted of the use of prophylactic antibiotics in patients with prosthetic heart valves who were undergoing diagnostic or operative procedures or heart catheterization at three hospitals. Compliance with AHA recommendations was only 30 percent (14 of 46) for procedures considered high risk for patients with prosthetic heart valves. Six (23 percent) of 26 patients who underwent right or left heart catheterization received prophylactic antibiotics (not recommended by AHA). Antibiotics were given to 42 (74 percent) of 57 patients who underwent surgical procedures considered at low risk of bacteremia, but only 33 (58 percent) received antibiotics that cover organisms commonly present at the site of the procedure. The results indicate that clinicians frequently do not administer prophylactic antibiotics in patients with prosthetic heart valves who are undergoing invasive procedures or do not follow published AHA guidelines when antibiotics are administered.

Perinephric abscess. Modern diagnosis and treatment in 47 cases

The records of 47 patients with a perinephric abscess diagnosed from 1975 to 1986 at 8 San Francisco Bay Area hospitals were reviewed. The mean age was 51 years. Fifty-five percent were females and 45%, males. The left kidney was affected in 47% of cases, the right kidney in 40%, both in 4%, and a transplanted pelvic kidney in 9%. Fever (55%), chills or diaphoresis (47%), flank pain (40%), abdominal pain (40%), and nausea or vomiting (32%) were the most common presenting symptoms. About half the patients had symptoms for 1 week or less and 12% had no symptoms. Fever was documented before diagnosis in 88% of patients. Abdominal mass (13%) or tenderness (49%), and flank mass (9%) or tenderness (42%) were seen less frequently, and 11% of patients did not have fever, flank, or abdominal findings. The most frequent underlying conditions included previous urologic surgery (45%), previous urinary tract infection (38%), diabetes mellitus (36%), and urinary tract stones (36%). Cultures of perinephric abscesses yielded gram-negative aerobes in 52% of patients, primarily Escherichia coli. Staphylococcus aureus was isolated in 26% of patients and anaerobes in 17%. A single pathogen was isolated in 71% and multiple isolates in 29%. Of interest and great potential therapeutic importance was culture of anaerobes, primarily Bacteroides spp. in 17%, Enterococcus spp. in 7%, and Candida albicans in 7%. Positive blood and urine cultures identified perinephric abscess organisms exactly in 58% and 37% of cases, respectively. Routine laboratory tests such as the white blood cell count and urinalysis were insensitive and non-specific for perinephric abscess. Leukocytosis and anemia at admission were seen in slightly more than half of the patients. For radiologic diagnosis, computerized tomographic scanning was most helpful. Ultrasound and intravenous pyelography were falsely negative in about one-third of cases. Mortality (13%) was low in this series when compared with earlier studies, and probably reflects modern medical care. Six patients (13%) died during hospitalization, 2 of whom had diagnosis of PNA established only at autopsy. Drainage of the perinephric abscess was carried out by open surgical drainage in 64% of patients, percutaneous drainage in 19%, and both in 13%. The initial procedure, whether open surgical drainage or percutaneous catheter drainage, was usually successful. Late complications included nephrocutaneous fistulas in 3 patients and disseminated candidiasis in 1 patient.

Unique differences in infectivity and seroreactivity of Toxoplasma harvested from mice infected for different lengths of time

For use in experiments, Toxoplasma of the RH strain are usually harvested from mouse peritoneal cavities 48 hr (2-day Toxoplasma) or more after intraperitoneal inoculation. In this report we show that Toxoplasma harvested at 24 hr (1-day Toxoplasma) after inoculation are much more infective for and replicate to a greater degree within mouse resident peritoneal macrophages in vitro and are much more resistant to the cidal activity of activated mouse peritoneal macrophages and resident rat peritoneal macrophages than are 2-day Toxoplasma. Ingestion of 1-day Toxoplasma by macrophages did not trigger the respiratory burst as measured by reduction of nitroblue tetrazolium (NBT), but coating 1-day Toxoplasma with specific antibody did result in reduced NBT. However, coating 1-day Toxoplasma with specific antibody did not markedly decrease infectivity for macrophages in vitro, unlike decreased infectivity observed when 2-day Toxoplasma are coated with specific antibody. Use of 1-day Toxoplasma in the dye test resulted in a 5-fold decrease in titer of specific antibody in human sera. Use of Toxoplasma harvested 24 hr after infection may serve as a new tool to probe virulence factors of Toxoplasma and of host cells' antimicrobial mechanisms.

Role of serology in the diagnosis of toxoplasmic lymphadenopathy

Serologic results obtained in 92 cases of toxoplasmic lymphadenopathy diagnosed by lymph node biopsy were reviewed, and guidelines for serologic diagnosis of this disease were established. When tests were first performed within six months of onset of lymphadenopathy, single high titers of IgG toxoplasma antibodies (suggestive of acute infection) were found with the Sabin-Feldman dye test and the direct agglutination test in 93% and 76% of cases, respectively. Observations of significant rises in titer were uncommon because of the late acquisition of sera. Within the first six months after the onset of lymphadenopathy, IgM toxoplasma antibody was demonstrable by the double-sandwich IgM enzyme-linked immunosorbent assay in 88% of cases and by the IgM-immunofluorescent antibody test in 78%. Twenty percent of patients who had serum samples drawn more than 12 months after onset lymphadenopathy still had IgM toxoplasma antibodies demonstrable by the enzyme-linked immunosorbent assay. No patient first tested six or more months after onset of lymphadenopathy was positive in the IgM-immunofluorescent antibody test. These results provide the basis for recommendations on the use of serologic tests for the diagnosis of acute toxoplasmic lymphadenopathy.

Clinical spectrum in 107 cases of toxoplasmic lymphadenopathy

Lymphadenopathy is the most frequent clinical manifestation of acute acquired infection with Toxoplasma in the immunocompetent individual. One hundred seven cases of histologically verified toxoplasmic lymphadenitis were reviewed in an effort to determine the usual modes of clinical presentation and the incidence of extranodal disease. Toxoplasmic lymphadenitis most frequently involved a solitary lymph node in the head and neck regions, without systemic symptoms or extranodal disease and with a benign clinical course. However, serious extranodal disease did occur in some patients and included myocarditis, pneumonitis, encephalitis, chorioretinitis, and transmission of the infection to the fetus. Case histories are presented to illustrate important points with respect to clinical presentation, complications, and diagnosis.

Ketoconazole promotes parasitological cure of mice infected with Trypanosoma cruzi

Administration of 120 mg/kg/day of ketoconazole for 9 weeks resulted in parasitological cure of at least 78.5% of mice infected with 10(5) blood trypanosomes of Trypanosoma cruzi, strain Y. These results and the fact that ketoconazole is widely used in humans for prolonged therapy of fungal infections without significant side effects strongly suggest that further evaluation of ketoconazole for treatment of Chagas disease is highly desirable.

Oral norfloxacin versus parenteral treatment of nosocomial urinary tract infection

In a multiclinic, randomized trial, oral norfloxacin, a fluoroquinolone antibacterial, was compared with several standard parenteral regimens for the treatment of nonbacteremic, hospital-acquired urinary tract infections. Parenteral antibiotic agents included aminoglycosides alone; aminoglycosides in combination with either broad-spectrum penicillins or first-generation cephalosporins; or cefotaxime alone. Ninety-two percent of bacterial isolates were multiresistant gram-negative rods including Pseudomonas aeruginosa (31 percent), Escherichia coli (17 percent), Klebsiella/Enterobacter species (14 percent), and Serratia species (11 percent). In the first evaluable 94 patients, norfloxacin was comparable to the parenteral agents in eliminating infecting bacteria from the urine. Similarly, combined bacterial eradication and clinical cure or improvement occurred in 96 percent (76 percent with cures, 20 percent with improvement) of those treated with norfloxacin and 88 percent (67 percent with cures, 21 percent with improvement) of those treated with parenteral agents. A negative outcome (i.e., failure, superinfection, or reinfection) occurred in two (4 percent) norfloxacin-treated patients versus six (12 percent) parenterally treated patients. Adverse effects were few, infrequently drug related, and rarely serious (one with norfloxacin versus two with parenteral agents). Additionally, drug, preparation, and administration costs were substantially less with oral norfloxacin compared with the parenteral agents. The data suggest, therefore, that oral norfloxacin can be substituted for commonly used parenteral antibiotic regimens, without any compromise in efficacy, in the treatment of nonbacteremic patients with multiresistant, nosocomial urinary tract infections.

The effects of cyclosporine on Toxoplasma gondii in vivo and in vitro

We examined the effect of cyclosporine on Toxoplasma infection in vivo and in vitro. Administration to mice of 150 mg/kg/day cyclosporine variably affected mortality in four separate experiments. IgG (Sabin-Feldman dye test) and IgM enzyme-linked immunosorbent assay antibody titers were significantly depressed in mice treated with cyclosporine. These results suggested the possibility that cyclosporine possesses anti-Toxoplasma activity. Thus, macrophages were incubated with cyclosporine before and after infection with Toxoplasma. Treatment with 0.5, 1, and 5 micrograms cyclosporine/ml during or after challenge of macrophage monolayers with Toxoplasma inhibited replication of Toxoplasma (and resulted in killing of Toxoplasma). The effect of cyclosporine on development of activated macrophages was studied. Cyclosporine administered to mice at a dose of 150 mg/kg/day neither accelerated nor delayed activation of macrophages (assessed by inhibition of Toxoplasma replication in vitro) by i.v. injection of either Corynebacterium parvum or Toxoplasma. Cyclosporine affects mortality variably in murine toxoplasmosis, depresses synthesis of IgG and IgM Toxoplasma antibody in vivo, does not prevent activation of macrophages in vivo, and possesses anti-Toxoplasma activity in vitro and perhaps in vivo. Cyclosporine may be the preferred immunosuppressive agent for recipients of an organ transplant who are at high risk for toxoplasmosis (e.g., seronegative recipients who have received organ from seropositive donors).

Mechanisms of killing of Toxoplasma gondii by rat peritoneal macrophages

Rats are resistant to Toxoplasma infection, and macrophages are thought to mediate this resistance. We performed a series of experiments to investigate the mechanism of the anti-Toxoplasma activity of resident rat peritoneal macrophages. Resident rat peritoneal macrophages killed more than 90% of ingested Toxoplasma gondii in vitro. This capacity was reduced progressively with the prolongation of culturing of macrophages in vitro before challenge with T. gondii. Exhaustion of the respiratory burst of macrophages with phorbol myristate acetate impaired their ability to kill and limit the replication of T. gondii. Histidine and diazabicyclooctane, presumed scavengers of singlet oxygen, were the only members of a battery of scavengers of metabolites of the respiratory burst that impaired the anti-Toxoplasma activity of macrophages. Ingestion of heat-killed Candida albicans by macrophages reduced large amounts of intracellular Nitro Blue Tetrazolium dye, whereas little dye was reduced by the ingestion of T. gondii. Challenge of macrophages with T. gondii released no detectable superoxide anion, as measured by the reduction of ferricytochrome c, whereas stimulation of macrophages with phorbol myristate acetate or ingestion of heat-killed Candida by macrophages released abundant superoxide anion. These data are consistent with the contributions of oxygen-dependent and oxygen-independent mechanisms to the anti-Toxoplasma activity of rat peritoneal macrophages. In addition, neonatal rats are known to be susceptible to Toxoplasma infection in vivo. However, resident neonatal rat peritoneal macrophages ingested and killed T. gondii to the same extent as did adult macrophages. Thus, the susceptibility of neonatal rats to Toxoplasma infection probably resides in other aspects of macrophage function or the immune response.

In vitro and in vivo effects of itraconazole against Trypanosoma cruzi

The synthetic imidazole, itraconazole, was examined for in vitro and in vivo activity against Trypanosoma cruzi. Mice treated with concentrations as low as 15 mg itraconazole/kg/day were completely protected against death due to infection with any of three different and highly virulent strains of T. cruzi. Treatment of infected mice with 120 mg itraconazole/kg/day for seven to nine weeks apparently resulted in the parasitologic cure as determined by negative hemocultures and subinoculations, negative serology for T. cruzi, and absence of parasites in histologic sections following completion of therapy. Peak serum levels of itraconazole after treatment of mice with the dose of the drug that provided protection against death were less than 1 microgram/ml. Experiments in vitro revealed that concentrations of itraconazole as little as 0.001 microgram/ml inhibited replication of intracellular amastigotes in macrophages. These results indicate that itraconazole has a remarkable activity against T. cruzi. Further investigation of intraconazole as a therapeutic agent for Chagas' disease may be warranted.

In vivo and in vitro effects of cyclosporin A on Trypanosoma cruzi

The in vivo and in vitro effects of cyclosporin A on T. cruzi were examined. Mice receiving 150 or 75 mg/kg/day of cyclosporin A and infected with T. cruzi 48 hr later had significantly higher parasitemias and earlier mortality than controls. Mice receiving cyclosporin A after infection had parasitemias similar to controls. Infections with both the reticulotropic Y and the miotropic CL strains of T. cruzi were enhanced by cyclosporin A. The in vitro replication of epimastigotes, but not the intracellular replication of amastigotes, in mouse macrophages was inhibited by 5 micrograms cyclosporin A/ml. Enhancement of the infection by cyclosporin A was not due to an effect on macrophages since the drug did not prevent development of activated macrophages capable of killing intracellular T. cruzi.

Open trial of imipenem/cilastatin therapy for serious bacterial infections

Imipenem is a new beta-lactam antibiotic with a wide spectrum of activity against gram-positive and gram-negative aerobic and anaerobic bacteria. The efficacy and toxicity of this drug, when administered parenterally in combination with the dehydropeptidase I inhibitor cilastatin, were studied in 41 hospitalized patients with serious infections. Clinical cure was achieved in 26 (79%) of the 33 patients who could be evaluated and microbiologic cure in 23 (85%) of the 27 patients who could be evaluated. Adverse clinical or laboratory reactions were observed in seven (17%) of the 41 patients. Thus, imipenem/cilastatin was highly effective in the treatment of a wide variety of serious bacterial infections.

Open lung biopsy in patients with acute leukemia

The results of open lung biopsy in 15 patients with acute leukemia, pulmonary infiltrates, neutropenia, and fever were reviewed. The patients averaged 26 hospital days of neutropenia and 20 hospital days of fever before open lung biopsy, and all patients received broad-spectrum antibacterial agents (mean 17 days) before open lung biopsy. Nine (67 percent) received amphotericin B prior to open lung biopsy (mean 22 days). Open lung biopsy yielded a specific clinically helpful diagnosis in six patients, but only two of these patients survived the hospitalization during which open lung biopsy was performed. Open lung biopsy detected fungus in four patients and leukemic infiltrates in two patients. Management was appropriately modified in these patients. In nine patients, a specific diagnosis of the pulmonary infiltrate was not obtained by open lung biopsy. Antimicrobial regimens were not changed substantially for these patients. In six patients, the results of open lung biopsy may have been misleading. Two patients had pulmonary fungal diseases at autopsy, undetected by open lung biopsy eight days and five weeks prior to death. Another patient had invasive aspergillosis and one had cytomegalovirus pneumonitis not detected by open lung biopsy. Two patients had false-positive preliminary histologic reports of pulmonary infection. On the basis of this experience, in this specific population of patients, open lung biopsy was often of little help in directing medical therapy or influencing clinical outcome.

In vitro and in vivo activities of formycin B against Trypanosoma cruzi

The inosine analog formycin B was examined for in vitro and in vivo activities against Trypanosoma cruzi. concentration of formycin B as low as 0.1 microgram/ml markedly inhibited intracellular multiplication of T. cruzi strains both in macrophages and in L929 cells. Mice infected with 10(5) blood form trypomastigotes of the highly virulent strain Y of T. cruzi were completely protected against death by treatment with 11.8 or 5.9 mg of formycin B per kg administered intraperitoneally each day for 19 days. Four different strains of T. cruzi were used, and each was susceptible to formycin B administered either intraperitoneally or orally. Parasitological cure, however, was not achieved with any of the treatments used, including prolonged treatment for up to 10 weeks. Formycin B has a remarkable capacity for inhibiting the in vitro intracellular replication of T. cruzi and protecting mice against death due to the acute infection with the organism. It does not appear, however, to be able to completely eliminate T. cruzi from infected mice.