Clinical Behavior of Implant Infections Due to Staphylococcus Epidermidis

Surgical implants and other foreign material are increasingly used in modern medicine to restore or to improve the function of the human body. Infection of an implant is associated with considerable morbidity due to frequent hospitalizations, surgery and antimicrobial treatment. The underlying mechanism is the formation of a bacterial biofilm on the surface of the implanted body. The recognition and diagnosis of implant infections is essential for further therapy and, above all, the decision to remove and exchange the implant.

Methods

We compared the data of 60 patients with implant infections with those of 60 patients with transient bacteremia caused by Staphylococcus epidermidis. The pathogens isolated from blood were characterized with regard to antimicrobial susceptibility and formation of biofilms using a static microtiter plate model. Wild type skin isolates from non-hospitalized healthy volunteers served as control with regard to antimicrobial susceptibility and biofilm formation.

Results

Clinical signs and symptoms, underlying diseases and outcome were not different in either group. However, patients with implant infection had fever over a longer time (mean 12 days versus 3 days, respectively, p & 0.05) and more often positive blood cultures than patients with transient bacteremia (3.1 versus 1.2, p & 0.05). Thrombocytopenia was observed in patients with implant infections but not in patients with transient bacteremia (p & 0.05). Biofilms were formed in 86.4 % of the isolates in implant infection, in 88.8 % in transient bacteremia and in 76.9 % of the isolates from healthy volunteers (not significant). Multi-resistance to penicillin, oxacillin, erythromycin, clindamycin, ciprofloxacin and trimethoprim was more common in the hospital strains than in the wild type strains (75.6 % versus 48.7 %, p & 0.05).

Conclusions

The clinical features of implant infections are indistinguishable from those of transient bacteremia. Persisting fever and multiple blood culture yielding the growth of skin flora bacteria are strong indicators for infection of implanted material. Biofilm formation and antimicrobial multiresistance, as common in implant infection as in transient bacteremia, seem to be accessory factors in infections due to Staphylococcus epidermidis.

[Left ventricular dysfunction in Churg-Strauss syndrome]

Churg-Strauss syndrome is a rare disorder characterized by hypereosinophilia and a systemic vasculitis occurring inpatients with asthma and allergic rhinitis. Vasculitis commonly affects the lungs, the heart, the skin, and the peripheral nervous system. Cardiac involvement is characterized by acute and constrictive pericarditis, myocarditis and endocarditis, as well as ischemic cardiomyopathy. Endomyocardial fibrosis similar to Loeffler's syndrome has been rarely described. In the presented case, a 43 year old man with a history of allergy and asthma suffered from increasing dyspnea, fever, pulmonary infiltates and cardiomyopathy. Laboratory studies were notable for marked hypereosinophilia. In a bronchoscopic lavage and transbronchial biopsy eosinophilic infiltrates accompanied by vasculitis were found, Churg-Strauss syndrome was diagnosed. Echocardiogram showed endomyocardial deposits in the apex of the right ventricle, right ventricular function was normal particular in the basal segments. The left ventricle was slightly enlarged and left ventricular function was impaired. The diastolic mitral in-flow showed a restrictive pattern. Additionally, a pericardial effusion was observed without signs of tamponade. The patient received corticosteroids, cyclophosphamide and cardiomyopathy-specific therapy and showed a marked improvement after 4 months.

Effect of preoperative prophylaxis with filgrastim in cancer neck dissection

BACKGROUND

Cancer surgery is known to lead to a deterioration in host defence mechanisms and an increase in susceptibility to infection after operation. Filgrastim enhances important antimicrobial functions of neutrophils including chemotaxis, phagocytosis and oxidative killing mechanisms.

METHODS

The effects of additional (all patients received perioperative 3 ' 25 mg kg-1 cefotiam and 1 ' 20 mg kg-1 metronidazole) preoperative prophylaxis with filgrastim (5 microg kg-1 12 h prior to surgery plus 5 microg kg-1 0 h prior to surgery) on neutrophil phagocytosis and reactive oxygen radical production and postoperative infections in 24 patients undergoing cancer neck dissection were studied. Phagocytic capacity was assessed by measuring the uptake of fluorescein isothiocyanate-labelled Escherichia coli and Staphylococcus aureus by flow cytometry. Reactive oxygen generation after phagocytosis was estimated by determining the amount of dihydrorhodamine 123 converted to rhodamine 123, intracellularly.

RESULTS

In the filgrastim-treated patients a higher neutrophil phagocytic capacity was seen intraoperatively, and 1-5 days postoperative, but not prior to surgery. Reactive oxygen radical production was significantly higher in filgrastim-treated patients prior to surgery, intraoperative and postoperative (1-5 days). 2/12 (17%) patients had postoperative infections in the filgrastim group and 9/12 (75%) patients had infections in the placebo group (P < 0.001). In particular, wound infections were recorded more often in the placebo group (1/12 vs. 6/12; P = 0.004).

CONCLUSION

We conclude that filgrastim enhances perioperative neutrophil function and could be useful in the prophylaxis of postoperative wound infections in patients undergoing cancer neck dissection.

Beneficial effects of protease inhibitors on body composition and energy expenditure: a comparison between HIV-infected and AIDS patients

OBJECTIVES

(i) To investigate whether protease inhibitor (PI) (nelfinavir)-containing highly active antiretroviral therapy (HAART) affects body composition differently in HIV-infected and AIDS patients without wasting syndrome. (ii) To delineate the changes in resting energy expenditure (REE) under PI therapy, and to determine whether sustained reductions in HIV RNA would decrease REE.

DESIGN

Prospective longitudinal cohort study with individually matched healthy controls.

SETTING

Tertiary care centre at a University Hospital.

METHODS

HIV-seropositive (n = 20) and AIDS patients (n = 17) with a plasma viral load of at least 10000 copies/ml and 37 healthy volunteers were enrolled. All participants were weight stable, free of acute opportunistic infections, and naive to PI therapy. Patients underwent testing of bioelectrical impedance analysis (BIA), indirect calorimetry and food intake, shortly before the initiation of HAART and 24 weeks thereafter.

RESULTS

Both patient groups gained weight, body mass index (BMI), and fat-free mass (FFM) (P < 0.05 versus baseline), whereas only AIDS patients gained fat mass. Increases were more pronounced in the AIDS group. REE was elevated compared with corresponding controls at baseline, and decreased similarly in HIV and in AIDS patients during PI therapy (P < 0.05). The reduction in the viral burden preceded the decrease in REE by several weeks.

CONCLUSION

Body composition and metabolic parameters improved during PI therapy in HIV-infected and AIDS patients without wasting. Although an early reduction in viral load as a result of HAART does not seem to influence REE directly, sustained viral load suppression may promote a decrease in energy expenditure.

Ticlopidine induced prolonged leucopenia in a patient with immunocytoma and chronic hepatitis C

Ticlopidine is increasingly used in the secondary prophylaxis in patients with arterial occlusive diseases. Neutropenia is a well known side effect of this drug. We report a case of a 73 year old woman who was admitted because of severe prolonged ticlopidine induced leucopenia. The past medical history included an immunocytoma of the IgM-kappa type diagnosed seven years ago with less than 10% infiltration of the bone marrow and a chronic hepatitis C. On admission the white cell count was 1000/microL. Ticlopidine was stopped. The white cell count did not increase within one week, thus filgastrim was applied on two consecutive days. The leucocyte count promptly increased to 6000/microL but consecutively dropped within the next fortnight again to levels below 500/microL forcing daily filgastrim application for another 9 days. Four months after the initiation of the therapy with filgastrim the patient had a white cell count of 4300/microL. We therefore conclude that in patients with a history of potentially bone marrow suppressing diseases the use of ticlopidine has to be carefully weighed against possible myelosuppressive effects.

Effect of polyclonal immunoglobulins on neutrophil phagocytic capacity and reactive oxygen production in patients with gram-negative septicemia

The effect of immunoglobulin (Ig) preparations on neutrophil phagocytic ability and oxidative burst in response to Escherichia coli stimulation was analyzed in 14 patients with gram-negative septicemia by an ex vivo whole blood assay using flow cytometry. In patients, neutrophils exhibited a decreased capacity to phagocytize E. coli and generate reactive oxygen products compared to healthy controls (median -68%, P < 0.01). The addition of both 7S-Ig and 19S-Ig enriched preparations in vitro resulted in a dose-dependent increase in neutrophil reactive oxygen production at concentrations of 10 g/l (median +153% and +211%, P < 0.01, respectively) and 20 g/l (median +205% and +282%, P < 0.01, respectively). A decreased neutrophil phagocytic ability was seen in patients with septicemia (median -58%) compared to healthy controls (P < 0.01). Again, the addition of 7S and 19S-Igs enhanced the phagocytic ability in a dose-dependent manner (10 g/l: median +56 and +126%; 20 g/l: median +126% and +165%, P < 0.01 for all). It can be concluded that both polyclonal Igs can increase depressed neutrophil reactive oxygen production and neutrophil phagocytosis in patients with gram-negative septicemia.

Human immunodeficiency virus: post-exposure prophylaxis

Post-exposure prevention is a combined modality approach to reducing HIV transmission. The recommendations are based on the risk of local prevalence and on the likelihood of transmission. In the light of the severe consequences of HIV infection, post-exposure prophylaxis after occupational exposure should be recommended. The medication, consisting of a potent antiretroviral combination (two nucleoside analogues and one reverse transcriptase inhibitor), should be available within two hours.

Effect of pentoxifylline on cytokine patterns in the therapy of complicated Plasmodium falciparum malaria

The effect of pentoxifylline (PTX) was tested for its capacity to modulate cytokine responses during therapy of severe Plasmodium falciparum malaria in a placebo-controlled, randomized study in 45 adult patients in Bangkok, Thailand. The patients received standard antimalarial treatment with artesunate (120 mg intravenously given immediately, then 60 mg every 12 hr for a total dose of 600 mg). The patients received either low-dose PTX (20 mg/kg/day, n = 15), high-dose PTX (40 mg/kg/day, n = 15), or placebo (n = 15) as continuous infusion for the first three days of antimalarial treatment. Tumor necrosis factor (TNF) and interleukin-6 (IL-6) plasma levels were markedly elevated in all patients prior to treatment. After 6 hr of high-dose PTX treatment, TNF and IL-6 levels significantly decreased while an increase in TNF and IL-6 levels was seen after 6 hr of low-dose PTX or placebo treatment (P < 0.01). After 12 and 24 hr of high-dose PTX infusion, TNF-receptor plasma concentrations were lower than in low-dose PTX- or placebo-treated patients (P < 0.01), whereas no differences between the groups with regard to IL-6 receptor levels were observed. We conclude that 40 mg/kg/day of PTX reduces plasma levels of TNF, IL-6, and TNF-receptor in patients with severe malaria. Whether this reduction improves clinical outcome remains to be determined.

Complement activation in severe Plasmodium falciparum malaria

We determined indices of plasma complement activation (C3, C4, Bb, C4d, iC3b, and SC5b-9), levels of tumor necrosis factor (TNF) and interleukin-6, and the APACHE II score in 23 patients with complicated Plasmodium falciparum malaria. On admission, plasma concentrations of Bb, SC5b-9, and C4d were markedly increased compared to healthy control subjects (n = 24) (4.5 +/- 1.9 vs 1.5 +/- 0.6 mg/L; 1125.7 +/- 496.9 vs 183.2 +/- 76.5 microg/L; and 15.7 +/- 5.7 vs 7.2 +/- 1.4 mg/L, P < 0.01 for all). In contrast C3 and iC3b concentrations were decreased (631.4 +/- 247 vs 947.3 +/- 243.2 and 105 +/- 17.9 vs 151.3 +/- 14.5 mg/L; P < 0.01 for both). Plasma C4 concentrations in malaria were not different from normal controls. Plasma Bb, C3, and iC3b levels normalized on day 7 of treatment, whereas SC5b-9 and C4d levels remained elevated. A significant correlation between elevated TNF levels and Bb (r = 0.507) and SC5b-9 (r = 0.448, P < 0.01 for both) and a negative correlation between iC3b and SC5b-9 and TNF levels existed (r = -0.537 and r = -0.466, P < 0.01 for both). In addition, a significant correlation between C3 and iC3b (r = 0.689) and C4 and C4d (r = 0.737) existed. However, no relation between clinical disease severity and complement fragments existed. The results demonstrate that both the classical and the alternative pathways of the complement system are profoundly activated in complicated malaria.

Prospective randomized comparison of cefodizime versus cefuroxime for perioperative prophylaxis in patients undergoing coronary artery bypass grafting

The effects of cefodizime and cefuroxime on neutrophil phagocytosis and reactive oxygen production in 54 patients undergoing elective coronary artery bypass grafting were studied. Both drugs were administered twice at a dosage of 40 mg/kg of body weight (pre- and intraoperative). Phagocytic capacity was assessed by measuring the uptake of fluorescein isothiocyanate-labeled Escherichia coli and Staphylococcus aureus by flow cytometry. Reactive oxygen generation after phagocytosis was estimated by determining the amount of dihydrorhodamine 123 converted to rhodamine 123 intracellularly. In both groups the mean phagocytic ability for E. coli and S. aureus decreased during surgery (-21 and -8%, respectively, for the cefodizime group and -39 and -38%, respectively, for the cefuroxime group; P < 0.05 for all). In the cefodizime group a normalization of mean E. coli and S. aureus neutrophil phagocytosis was seen on day 5 (+9 and -4% compared to preoperative values; P > 0.35 for both), whereas in cefuroxime-treated patients phagocytic ability remained depressed (-37 and -31%; P < 0.04 for both). In both groups mean neutrophil reactive oxygen intermediate (ROI) production after E. coli and S. aureus phagocytosis increased during cardiopulmonary bypass (+44 and +83%, respectively, in the cefodizime group and +58 and +73%, respectively, in the cefuroxime group; P < 0.05 for all). One day after surgery E. coli- and S. aureus-driven neutrophil ROI production was not different from the preoperative values (-2 and +12%, respectively, for the cefodizime group and +7 and +15%, respectively, for the cefuroxime group; P > 0.15 for all). Postoperative serum levels of the C-reactive protein on days 2 and 7 were lower in cefodizime-treated patients (19 +/- 6 and 4 +/- 2 mg/liter versus 23 +/- 6 and 11 +/- 5 mg/liter; P < 0.05 for both). In addition to cefodizime's antimicrobial activity during perioperative prophylaxis, its use in coronary artery bypass grafting can prevent procedure-related prolonged postoperative neutrophil phagocytosis impairment.

Rapid susceptibility testing of fungi by flow cytometry using vital staining

A 1-h assay for antifungal susceptibility testing measuring the impairment of fungal metabolic activity was developed. Yeast viability was analyzed by flow cytometry with a novel fluorescent probe, FUN-1, which emits a red fluorescence when the yeast is metabolically active. For nine Candida albicans strains tested, this method yielded results comparable to those obtained by the standard M27 procedure for amphotericin B, flucytosine, fluconazole, and ketoconazole. Whether the flow cytometry antifungal susceptibility test results correlate with the in vivo activities of the drugs remains to determined.

The effect of artemisinin on granulocyte function assessed by flow cytometry

The effect of dihydroartemisinin, artemisinin and artesunate (0.1, 0.5, 5 and 50 mg/L) on phagocytic function and release of reactive oxygen products by neutrophils was studied by flow cytometry. Incubation with dihydroartemisinin, artemisinin and artemether resulted in a decreased capacity to phagocytose Escherichia coli (0.1-50 mg/L: 62-40%, 66-32% and 59-47% of the control values, respectively; P < 0.001 for all). Conversely, the derivatives enhanced the intracellular generation of reactive oxygen intermediates (0.1-50 mg/L: 146-140%, 174-197% and 188-136% of the control values, respectively; P < 0.001 for all). Artemisia derivatives enhance the reactive oxygen response of neutrophils but depress their phagocytic ability at therapeutic blood levels.

Effect of single oral dose of azithromycin, clarithromycin, and roxithromycin on polymorphonuclear leukocyte function assessed ex vivo by flow cytometry

Azithromycin was given as a single oral dose (20 mg/kg of body weight) to 12 volunteers in a crossover study with roxithromycin (8 to 12 mg/kg) and clarithromycin (8 to 12 mg/kg). Flow cytometry was used to study the phagocytic functions and the release of reactive oxygen products following phagocytosis by neutrophil granulocytes prior to administration of the three drugs, 16 h after azithromycin administration, and 3 h after clarithromycin and roxithromycin administration. Phagocytic capacity was assessed by measuring the uptake of fluorescein isothiocyanate-labeled bacteria. Reactive oxygen generation after phagocytosis of unlabeled bacteria was estimated by the amount of dihydrorhodamine 123 converted to rhodamine 123 intracellularly. Azithromycin resulted in decreased capacities of the cells to phagocytize Escherichia coli (median [range], 62% [27 to 91%] of the control values; P < 0.01) and generate reactive oxygen products (75% [34 to 26%] of the control values; P < 0.01). Clarithromycin resulted in reduced phagocytosis (82% [75 to 98%] of control values; P < 0.01) but did not alter reactive oxygen production (84% [63 to 113%] of the control values; P > 0.05). Roxithromycin treatment did not affect granulocyte phagocytosis (92% [62 to 118%] of the control values; P > 0.05) or reactive oxygen production (94% [66 to 128%] of the control value; P > 0.05). No relation between intra- and/or extracellular concentrations of azithromycin and/or roxithromycin and the polymorphonuclear phagocyte function and/or reactive oxygen production existed (P > 0.05 for all comparisons). These results demonstrate that the accumulation of macrolides in neutrophils can suppress the response of phagocytic cells to bacterial pathogens after a therapeutic dose.

Dysregulation of the polymorphonuclear leukocyte--Candida spp. interaction in HIV-positive patients

OBJECTIVE

In HIV-infected patients there is an increased frequency of fungal infections. Dysregulation of the response of phagocytic cells to fungal pathogens may be involved.

DESIGN

Phagocytosis of Candida spp., consecutive intracellular production of reactive oxygen species, and candicidal activity were analysed in polymorphonuclear leukocytes (PML) from HIV-1-infected patients, who were at stage C3 of the 1993 revised Centers for Disease Control and Prevention classification system, by means of flow cytometry.

METHODS

Phagocytic ability was assessed by measuring uptake of fluorescein isothiocyanate-labelled Candida albicans, C. krusei and C. glabrata. Reactive oxygen intermediate production was estimated by the quantity of dihydrorhodamine-123 converted to rhodamine-123 intracellularly. The candicidal effect was assessed by the propidium iodide uptake of killed yeast cells.

RESULTS

As compared to PML of healthy, HIV-negative controls, PML of AIDS patients exhibited an increased phagocytic activity and a similar ability to generate reactive oxygen products. In contrast, PML of AIDS patients displayed a decreased candicidal activity (P < 0.05 compared to controls).

CONCLUSION

These results suggest that in patients with advanced HIV-1 infection the impairment of non-oxidative killing mechanisms of phagocytic cells may contribute to the high incidence of fungal infections.

High-dose catecholamine treatment decreases polymorphonuclear leukocyte phagocytic capacity and reactive oxygen production

Flow cytometry was used to study phagocytic function (uptake of fluorescein isothiocyanate-labeled bacteria) and release of reactive oxygen products (dihydrorhodamine 123 converted to rhodamine 123) following phagocytosis by neutrophil granulocytes of heparinized whole blood treated with adrenaline, noradrenaline, dopamine, dobutamine, or orciprenaline. Reduced neutrophil phagocytosis and reactive oxygen production were seen at 12 micrograms of adrenaline per liter (72% each compared with control values); at 120 micrograms of noradrenaline (72% each), dobutamine (83 and 80%, respectively), and orciprenaline (81 and 80%, respectively) per liter; and at 100 micrograms of dopamine per liter (66 and 70%) (P < 0.05 for all). At these dosages, neutrophil chemotaxis was reduced to < 50% of control values for all catecholamines. Treatment with catecholamines at lower dosages had no significant effect on phagocytosis or generation of reactive oxygen products or chemotaxis. The phagocytic capacity of granulocytes was related to the generation of reactive oxygen products (r = 0.789; P < 0.05). The results demonstrate that catecholamines have a suppressive effect on the response of phagocytic cells to bacterial pathogens at high therapeutic levels in blood.

Elevated levels of soluble CD14 in serum of patients with acute Plasmodium falciparum malaria

Serum sCD14, tumour necrosis factor-alpha (TNF-alpha), IL-6, and endotoxin were analysed in 45 patients with complicated malaria, in 14 patients with Gram-negative septicaemia and in 24 healthy subjects by ELISA. Malaria patients with renal failure (n = 16) had higher levels than patients without renal failure (n = 29) (8116 + 1440 micrograms/l versus 9453 + 1017 micrograms/l; P < 0.05) and both had higher levels than patients with septicaemia (6155 + 1635 micrograms/l) and normal subjects (2776 + 747 micrograms/l). A significant correlation between sCD14 and IL-6 (r = 0.756) and TNF (r = 0.822) existed. However, no relation between sCD14 and serum endotoxin or indices of clinical disease severity (parasitaemia, fever, parasite or fever clearance time) was seen. Although the role of sCD14 in malaria remains to be determined, elevated levels may participate in the inflammatory response in complicated malaria.

Comparison of vancomycin, teicoplanin, metronidazole, and fusidic acid for the treatment of Clostridium difficile-associated diarrhea

We conducted a prospective, randomized study to compare the efficacy of oral fusidic acid, oral metronidazole, oral vancomycin, and oral teicoplanin for the treatment of Clostridium difficile-associated diarrhea. Treatment resulted in clinical cure for 94% of the patients who were treated with vancomycin, 96% of those treated with teicoplanin, 93% of those treated with fusidic acid, and 94% of those treated with metronidazole. Clinical symptoms recurred in 16% of patients treated with vancomycin, 7% of those treated with teicoplanin, 28% of those treated with fusidic acid, and 16% of those treated with metronidazole. There was asymptomatic carriage of C. difficile toxin in 13% of patients treated with vancomycin, 4% of those treated with teicoplanin, 24% of those treated with fusidic acid, and 16% of those treated with metronidazole. No adverse effects related to therapy with vancomycin or teicoplanin were observed. Considering the costs of treatment, our findings suggest that metronidazole is the drug of choice for C. difficile-associated diarrhea and that glycopeptides should be reserved for patients who cannot tolerate metronidazole or who do not respond to treatment with this drug.

Increased serum concentrations of the carboxy-terminal-cross-linked telopeptide of collagen type I in patients with acute Plasmodium falciparum malaria

We determined serum levels of the carboxy-terminal-cross-linked telopeptide and carboxy-terminal propeptide of type I collagen (ICTP and PICP) in 24 patients with acute complicated Plasmodium falciparum malaria prior to and 7, 14, 21, and 28 days after therapy by radioimmunoassay in Bangkok, Thailand. Elevated levels of ICTP were observed in patients (mean +/- SD concentration 16.7 +/- 5.8 ng/ml), compared with normal controls (3.1 +/- 1.3 ng/ml), during the acute phase of the disease. In contrast, serum concentrations PICP were not different between patients and controls (168 +/- 63 and 144 +/- 57 ng/ml, respectively). After therapy serum ICTP concentrations decreased but remained elevated even 28 days after the malaria attack (10.3 +/- 2.9 ng/ml). These findings suggest an increased production or release of ICTP in P. falciparum malaria, which could implicate an alteration of extracellular matrix during P. falciparum malaria.

Mild intraoperative hypothermia reduces production of reactive oxygen intermediates by polymorphonuclear leukocytes

Mild hypothermia directly impairs numerous immune functions in vitro. However, the in vivo effects of mild hypothermia on neutrophil phagocytosis and oxidative killing remain unknown. We tested the hypothesis that mild intraoperative hypothermia decreases neutrophil phagocytic capacity and generation of reactive oxygen intermediates (a measure of oxidative killing). Additionally, we evaluated the effects of in vitro temperature manipulations on each function. Thermal management was randomly assigned in 10 surgical patients, causing intraoperative core temperatures to range from 33 to 37 degrees C. Production of reactive oxygen intermediates and neutrophil phagocytosis were evaluated using flow cytometry at ambient temperature. Phagocytic capacity was assessed by uptake of fluorescein isothiocyanate-labeled Escherichia coli. Reactive oxygen production was estimated by the intracellular conversion of dihydrorhodamine 123 to rhodamine 123. Blood samples were obtained preoperatively, 1 h after surgery started, and 2 h postoperatively. Blood was also obtained from 10 matched control subjects and tested at 32, 37, and 40 degrees C. Neutrophil oxidative and phagocytic capacities were significantly reduced intraoperatively, compared with preoperative and postoperative values. Intraoperative production of reactive oxygen species was linearly related to core temperature. In contrast, there was no correlation between core temperature and phagocytic activity. In vitro production of reactive oxygen intermediates increased sixfold from 32 to 40 degrees C. In vitro phagocytic capacity increased fourfold in this temperature range. Production of oxidative intermediates was most closely related to intraoperative core temperature, decreasing nearly fourfold over a 4 degree C range. This in vitro temperature dependence was matched in vitro. Impaired neutrophil oxidative killing may contribute to the observed hypothermia-induced reduction in resistance to infection.

Decreased serum levels of TGF-beta in patients with acute Plasmodium falciparum malaria

Apart from cellular immunity and immunopathology, various cytokines have been implicated in malaria-associated immunosuppression. In this study, serum levels of transforming growth factor-beta (TGF-beta) were determined with an enzyme-linked immunosorbent assay in 37 patients with acute Plasmodium falciparum malaria prior to, during, and after therapy and in 17 healthy controls in Bangkok, Thailand. Patients were treated with artesunate and mefloquine. TGF-beta serum levels were found decreased prior to treatment (14 +/- 11 pg/ml versus 63 +/- 15 pg/ml in healthy controls; P < 0.05). The serum concentrations of TGF-beta increased after initiation of treatment and were within normal range on day 21. Serum levels of both tumor necrosis factor-alpha (TNF-alpha) and soluble TNF-receptor 55 kDa were inversely correlated to serum levels of TGF-beta (r = -0.667 and r = -0.592, n = 37; respectively, P < 0.05 for both). No correlation between parasitemia and serum levels of TGF-beta could be found. The results are compatible with a decreased production and release, an enhanced clearance or utilization, or tissue accumulation of TGF-beta in acute P. falciparum malaria.

Effect of cefodizime and ceftriaxone on phagocytic function in patients with severe infections

Thirty patients with severe bacterial infections were treated with 50 mg of cefodizime per kg of body weight once daily or 50 mg of ceftriaxone per kg once daily for 10 +/- 3 days. The effect of cefodizime and ceftriaxone on the phagocytic capacity and generation of reactive oxygen intermediates after phagocytosis by granulocytes was assessed prior to, during, and after therapy. Flow cytometry was used to study phagocytic capacity by measuring the uptake of fluorescein-labeled bacteria. The generation of reactive oxygen intermediates after phagocytosis was estimated by the quantification of the intracellular conversion of dihydrorhodamine 123 to rhodamine 123. Prior to therapy, patients in both groups exhibited a decreased capacity to phagocytize Escherichia coli and subsequently to generate reactive oxygen intermediates. Granulocyte function increased after the initiation of therapy and normalized within 7 days for the ceftriaxone-treated patients and within 3 days for the cefodizime group (P < 0.05). In the cefodizime group, an enhancement of phagocytic capacity was observed 14 days after the initiation of therapy (P < 0.05). Prior to therapy, phagocytic capacity was significantly correlated with the generation of reactive oxygen products (r = 0.674 and P < 0.005).

Elevated serum levels of IL-10 and IFN-gamma in patients with acute Plasmodium falciparum malaria

Serum levels of interleukin-10 (IL-10) and interferon-gamma (IFN-gamma) were determined in 37 patients with acute Plasmodium falciparum malaria in Bangkok, Thailand. Serum levels of IL-10 and IFN-gamma were markedly elevated in patients with malaria prior to treatment (717 +/- 260 pg/ml versus 2.2 +/- 1.3 pg/ml in healthy controls; 123 +/- 71 pg/ml versus 29 +/- 9 pg/ml, respectively; mean +/- SD). Serum levels of IFN-gamma and IL-10 dropped significantly during treatment and were normal 14 and 21 days, respectively, after treatment was started. Prior to therapy a correlation between serum levels of IFN-gamma and IL-10 existed (r = 0.563). These results suggest that stimulatory and inhibitory cytokines for macrophage activation and/or antibody production (i.e., TH1- and TH2-type immunoreaction, respectively) are coexpressed during acute P. falciparum infection and stress the multifactorial network between host and parasite in malaria immunology.

Soluble endothelium-associated adhesion molecules in patients with Graves' disease

The targeting and recruitment of inflammatory cells to vascular endothelium in Graves' disease (GD) is mediated by intercellular adhesion molecule-1 (ICAM-1), endothelial leucocyte adhesion molecule-1 (ELAM-1), and vascular cell adhesion molecule-1 (VCAM-1). We have studied serum levels of soluble ICAM-1 (sICAM-1), soluble ELAM-1 (sELAM-1), and soluble VCAM-1 (sVCAM-1) in patients with GD (n = 21) and in patients with iodine-deficient goitre (IDG) (n = 23). The serum levels of sICAM-1 were markedly elevated in patients with GD before treatment with thiamazole (median 560 ng/ml versus 185 ng/ml in patients with IDG). In addition, elevated serum concentrations of sELAM-1 (median 85 ng/ml versus 33 ng/ml, respectively) and sVCAM-1 (median 42 ng/ml versus 15 ng/ml, respectively) were observed in patients with GD (P < 0.01 for all). The serum levels of sELAM-1 and sVCAM-1 dropped significantly after initiation of therapy and were within the normal range after 4, and 8 weeks of therapy, respectively. Serum levels of sICAM-1 were elevated even after 8 weeks of therapy. Serum levels of sVACM-1 and sICAM-1 correlated with the serum concentrations of anti-thyroid-stimulating hormone (TSH)-receptor antibodies (TSHR-R) (n = 21; r = 0.929 and r = 0.810, respectively) and anti-thyroid peroxidase antibodies (TPO-Ab) (n = 21; r = 0.673 and r = 0.750, respectively). However, no correlation between sELAM-1 and TPO-Ab, TSHR-R, and anti-thyroglobulin antibodies (Tg-Ab), respectively, could be found. In addition to thyroid hormones and autoantibodies, serum concentrations of sELAM-1 and sVCAM-1, but not sICAM-1, could be useful as clinical markers for disease activity.

Serum laminin in malaria

AIM

To determine serum laminin concentrations in patients with uncomplicated Plasmodium falciparum malaria.

METHODS

An enzyme linked immunosorbent assay (ELISA) was used to determine serum laminin concentrations in 54 patients with acute uncomplicated P falciparum malaria during and after treatment, and in 17 control subjects in Bangkok, Thailand.

RESULTS

Raised concentrations of soluble laminin were observed in patients (mean (SD) concentration 628 (225) ng/ml), compared with normal controls (490 (116) ng/ml), during the acute phase of the disease. During treatment, serum laminin concentrations decreased and returned to normal within three days. Serum laminin concentrations were correlated with parasite counts before treatment, and with the serum concentration of soluble intercellular adhesion molecule-1 (ICAM-1), soluble E-selectin, and soluble tumour necrosis factor receptor at 55 kilodaltons.

CONCLUSIONS

These findings are compatible with an increased production or release of laminin in P falciparum malaria, which could indicate a role for the subendothelial basement membrane in the pathogenesis of the disease.