Interleukin 6, but not tumour necrosis factor-alpha, is a good predictor of severe infection in febrile neutropenic and non-neutropenic children with malignancy

OBJECTIVE: Interleukin-6 (IL6), tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) are important mediators of the inflammatory response in human infection. The aim of this study was to determine the relationship between serum levels of IL6, TNF-alpha, IFN-gamma and CRP in febrile children with malignant disease, and relate these levels to aetiology of fever, presence of neutropenia and the effect of untreated malignancy. METHODS: 110 febrile episodes in 70 children with malignant disease were included. Cytokine analyses were performed with sensitive immunoradiometric methods using double monoclonal antibodies. RESULTS: IL6 had a sensitivity of 74% in detecting sepsis in children with fever and malignant disease. This sensitivity was not influenced by the presence of neutropenia or newly diagnosed malignancy. A positive correlation between IL6 and the CRP levels on the following day was observed (r = .53). TNF-alpha was elevated in 22% of the episodes and mean levels were significantly higher in untreated malignancy but lower in neutropenic patients. IFN-gamma was elevated in 18% of cases and correlated strongly with mean TNF-alpha levels. CONCLUSIONS: IL6 is a sensitive and early predictor of bacterial infection in both neutropenic and non-neutropenic febrile children with malignancy. It is more sensitive than CRP in detecting sepsis, but the predictive value is too low to allow IL6 levels to influence initial treatment decisions in patients with granulocytopenia. TNF-alpha production seems to be impaired in neutropenic children and serum TNF-alpha cannot be employed as an indicator of bacterial infection.     

Plasma endotoxin and cytokine levels in neutropenic and non-neutropenic bacteremic patients

Plasma endotoxin, tumor necrosis factor-alpha (TNF-alpha), interleukin 1 beta (IL-1 beta), interleukin 1 receptor antagonist (IL-1ra), and interleukin 6 (IL-6) concentrations in 69 bacteremic patients were compared with those in 54 nonbacteremic patients suffering from suspected bacterial infections. Only three (11%) of the 27 patients with gram-negative bacteremia showed detectable levels of endotoxin. TNF-alpha was detected in 6% of the bacteremic patients and in none of the nonbacteremic patients. Median IL-6 levels were significantly higher in bacteremic than in nonbacteremic patients (55 vs. 0 pg/ml, p = 0.0008). IL-6 concentrations were similar in neutropenic and non-neutropenic bacteremic patients (median 55 vs. 74 pg/ml). In contrast, neutropenic bacteremic patients had significantly lower concentrations of IL-1ra than non-neutropenic bacteremic patients (250 vs. 1,950 pg/ml, p < 0.0001). Patients with fatal bacteremia had significantly higher concentrations of IL-6 and IL-1ra than the survivors (median, 450 vs. 40, p = 0.012 and 7,600 vs. 420 pg/ml, p = 0.0075, respectively). Determinations of endotoxin or TNF-alpha in patients with suspected bacteremia failed to offer clinically relevant data on the prognosis of these patients. IL-6 levels correlated with both the presence of bacteremia and the risk of death. Granulocytopenic patients with bacteremia had lower levels of circulating IL-1ra than patients with normal granulocyte counts, and these levels correlated with poor outcome.     

Clinical significance of serum cytokine patterns during start of fever in patients with neutropenia

Serum concentrations of tumour necrosis factor alpha (TNF-alpha), interleukin-1 receptor antagonist (IL-1ra), interferon gamma (IFN-gamma), interleukin-6 (IL-6) and interleukin-10 (IL-10) were studied in 31 patients with haematological malignancies during febrile neutropenia. Samples were obtained when blood cultures were performed (time 0) and, when possible, after 2, 4, 6, 12 and 24 h. Increased levels of all cytokines were detected after start of fever with peak values in gram-negative (Gr-) bacteraemias after 2 h (TNF-alpha, IL-1ra and IFN-gamma), 4 h (IL-6) and 6 h (IL-10), respectively. At time 0 the median TNF-alpha value was higher in the Gr- group (80 pg/ml; range 54-516 pg/ml) as compared to both gram-positive bacteraemias (Gr+, 14 pg/ml; range 7-60 pg/ml; P < 0.05) and blood culture negative episodes (BCN, 8 pg/ml; range 0-87 pg/ml; P < 0.05). Furthermore, the peak values of TNF-alpha, IL-1ra, IL-6 and IL-10 during the 24 h study period were significantly and/or numerically higher in the Gr- group in comparison to the Gr+ and BCN groups, respectively. It may be concluded that neutropenic patients have increased levels of both pro- and anti-inflammatory cytokines at start of fever, with the highest values recorded during the first hours in Gr- bacteraemias. Prospective studies will show whether monitoring of serum cytokines may be used as an early diagnostic tool before results of blood cultures are available, which may have important therapeutic implications.     

Tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-6 concentrations in cerebrospinal fluid predict ventriculoperitoneal shunt infection

OBJECTIVE: To determine the diagnostic value of cerebrospinal fluid tumor necrosis factor (TNF)-alpha, interleukin (IL)-1 beta, and IL-6 released into the cerebrospinal fluid of patients with ventriculoperitoneal shunt infection. DESIGN: Prospective, observational study. SETTING: University teaching hospital. PATIENTS: Sixty-four patients requiring cerebrospinal fluid aspiration for suspected ventriculoperitoneal shunt malfunction. INTERVENTIONS: Cerebrospinal fluid samples were obtained by shunt aspiration at the time of patient presentation. MEASUREMENTS AND MAIN RESULTS: TNF-alpha and IL-1 beta concentrations were measured by enzyme-linked immunosorbent assay, and IL-6 activity by bioassay. The sensitivity, specificity, predictive values, and overall efficiency for each cytokine were determined based on the cerebrospinal fluid culture results. Ten patients had positive cerebrospinal fluid cultures, eight of which yielded Staphylococcus species, and one each Acinetobacter and Pseudomonas. Cerebrospinal fluid TNF-alpha, IL-1 beta, IL-6, protein, and leukocyte concentrations were significantly increased in patients with shunt infection. Cerebrospinal fluid IL-6 activity had the highest diagnostic accuracy of the cytokines evaluated, with sensitivity of 80% and specificity of 98%. CONCLUSIONS: The presence of cerebrospinal fluid inflammatory cytokines strongly suggests ventriculoperitoneal shunt infection. Detection of these cytokines in the cerebrospinal fluid could be used for earlier diagnosis of bacterial infection.     

IL-6 and IL-8 levels in plasma during hematopoietic progenitor transplantation

BACKGROUND AND OBJECTIVE: The relationship between cytokine concentrations and transplant-related complications has been studied in bone marrow transplant patients. The changes in TNF-alpha, IL-1 and IL-6 concentrations after transplantation are well documented in the literature but this is not the case for IL-8. The purpose of the present study was to investigate prospectively the plasma concentration of these cytokines and their relationship to transplant-related complications. DESIGN AND METHODS: Pro-inflammatory cytokine (TNF-alpha, IL-1, IL-6 and IL-8) levels in plasma were determined in a group of 53 patients undergoing hematopoietic progenitor transplantation. Plasma samples were collected weekly from day -7 to day +35 and stored at -70 degrees C until assayed by ELISA. The major transplant-related toxicities registered were: veno-occlusive disease (VOD), acute graft-versus-host disease (GVHD), infectious episodes, renal failure and mucositis. RESULTS: In spite of the great variability of plasma cytokine profiles between the different patients, we came to various conclusions. Patients' TNF-alpha and IL-1 concentrations correlated well over time. IL-6 and IL-8 profiles were similar and correlated well with febrile episodes. In some cases, an increase in IL-6 preceded hematologic recovery. In our study, increased levels of TNF-alpha, IL-6 and especially IL-8 correlated with hepatic or renal dysfunction as evaluated by increased bilirubin and creatinine in plasma, while pulmonary complications correlated only with increased IL-6 levels. Allogeneic transplant patients had a tendency to have higher TNF-alpha concentrations than autologous transplant patients, probably because an allogeneic transplant is associated with more transplant-related toxicity. Basal disease usually had no effect on cytokine profiles. INTERPRETATION AND CONCLUSIONS: IL-6 and IL-8 were the only cytokines studied whose increase correlated with febrile episodes. High IL-8 values may be a useful predictor of renal dysfunction and pulmonary disease and seems to trigger off high IL-6 levels. Plasma TNF-alpha and IL-1 concentrations during the posttransplant period have not been shown to be predictive of the development of transplant-related complications, and none of the profiles was recognized to be specific for a particular complication in this study.     

Examination of wear in Duraloc acetabular components: two- to five-year evaluation of Hylamer and Enduron liners

BACKGROUND: The purpose was to determine the prognostic value of interleukin (IL) 1-alpha, IL-6 and IL-8 in cervico/vaginal secretion for preterm birth (<37 weeks of gestation) in twin pregnancies. METHODS: The study included screening of 121 women with twin pregnancies with sampling at 24, 26, 28, 30, 32 and 34 weeks of gestation. IL-1alpha, IL-6 and IL-8 was analyzed with ELISA immunoassays. The detection limit was 30 pg/mL for IL-1 and IL-8 and 40 pg/mL for IL-6. Vaginal fluid was smeared and dried for later evaluation of bacterial vaginosis (presence of clue cells). RESULTS: Spontaneous preterm birth occurred in 36 women and 65 women were delivered at term. IL-8 was significantly higher (p=0.03) in samples from women delivered preterm (median 3.72 ng/g mucus, range <0.07-220.00) compared with samples from women delivered at term (median 3.03 ng/g mucus, range <0.08-378.60). At 28 weeks of gestation, IL-8 (cut off 1.75 ng/g mucus) was associated with preterm delivery (relative risk 2.2, CI 95% 1.1-4.5) with a sensitivity, specificity, positive and negative predictive value of 78.8, 45.8, 44.8 and 79.4%, respectively. The levels of IL-1alpha and IL-6 were not significantly associated with preterm birth. Bacterial vaginosis was found in 47/541 (8.7%) samples analyzed. The levels of IL-1alpha and IL-8 were significantly higher in samples positive for bacterial vaginosis than in negative samples (p<0.0001 and p<0.01, respectively). There was no significant association between the level of IL-6 and bacterial vaginosis. CONCLUSIONS: IL-8, but not IL-1alpha and IL-6, was associated with preterm delivery but the relationship was too weak to be of predictive value for preterm birth in twin pregnancies. IL-1alpha and IL-8, but not IL-6, were associated with bacterial vaginosis.     

Generation of chromosome fragment specific bovine DNA sequences by microdissection and DOP-PCR

Trends in causative organisms and sources of infection were studied in a series of 288 episodes of bacteremia in neutropenic cancer patients observed in a single institution from 1986 to 1993. The incidence of bacteremia increased significantly from 20 episodes per 1000 admissions in 1986 to 50 episodes per 1000 admissions in 1993 (p = 0.00001). Over the study period, a continuous increment in gram-positive bacteremia, which reached 81% of episodes in 1993 (p = 0.000001), was observed. Conversely, the incidence of gram-negative bacteremia remained stable. Coagulase-negative staphylococci and viridans group streptococci were the most commonly isolated pathogens. Bacteremia caused by coagulase-negative staphylococci increased from 3 episodes per 1000 admissions to 19 episodes per 1000 admissions (p = 0.0001), and viridans group streptococci bacteremia increased from 0 episodes per 1000 admissions to 19 episodes per 1000 admissions (p = 0.000001). The upward trend in gram-positive bacteremia appeared to be related to a significant increase in both intravascular catheters (p = 0.003) and oral mucositis (p = 0.003) as sources of infection. Specific strategies to prevent chemotherapy-induced mucositis and catheter-related bacteremia merit further investigations.     

Higher levels of interleukin-6 in cystic fluids from patients with malignant versus benign ovarian tumors correlate with decreased hemoglobin levels and increased platelet counts

BACKGROUND: Recently, high pretreatment platelet counts and low pretreatment hemoglobin levels were found to be negative prognostic factors in patients with ovarian cancer. Interleukin-6 (IL-6) is a multifunctional cytokine with a diversity of functions leading to the induction of C-reactive protein (CRP), increased platelet counts, and low hemoglobin levels. Different epithelial ovarian cancer cell lines are found to produce varying amounts of IL-6. In this study, a possible relationship between IL-6 levels in cystic fluids of benign and malignant ovarian tumors and pretreatment serum CRP, platelet counts, and hemoglobin levels was evaluated. METHODS: A bioassay and enzyme-linked immunosorbent assay (ELISA) were performed to determine the IL-6 levels in cystic fluids and serum from 42 patients with benign and malignant ovarian tumors. RESULTS: The median IL-6 level was higher in cystic fluids of malignant tumors (n = 21) when compared with cystic fluids of benign tumors (n = 21) (P < 0.01 for bioassay and ELISA). Serum IL-6 levels in patients with malignant tumors were not significantly higher compared with IL-6 levels in patients with benign tumors, whereas CRP levels were higher in patients with malignant tumors (P < 0.01). Cystic fluid IL-6 levels were related to serum CRP levels (r = 0.60, P < 0.01 [bioassay]; r = 0.41, P < 0.01 [ELISA]), and were related inversely to hemoglobin levels (r = -0.57, P < 0.01 [bioassay]; r = 0.54, P < 0.01 [ELISA]). CONCLUSIONS: IL-6 levels are higher in cystic fluids of malignant ovarian tumors compared with benign tumors. The relationship of cystic fluid IL-6 levels with CRP, platelet counts, and hemoglobin levels suggests a possible causative role of tumor-derived IL-6 in the appearance of general side effects of ovarian cancer, which recently have been recognized as prognostic factors.     

Bacteremic pneumonia in neutropenic patients with cancer: causes, empirical antibiotic therapy, and outcome

BACKGROUND: Bacteremic pneumonia is a major cause of death among neutropenic patients with cancer. METHODS: We analyzed the causes, empirical antibiotic therapy, and outcome of 40 consecutive cases of bacteremic pneumonia identified among 408 episodes of bacteremia in adult neutropenic patients with cancer, prospectively documented from 1986 to 1995. RESULTS: The most frequent causative organisms were Pseudomonas aeruginosa (17 cases), Streptococcus pneumoniae (12 cases), Escherichia coli (5 cases), and Streptococcus mitis (3 cases). Overall, P. aeruginosa and S. pneumoniae caused 72.5% of all episodes of bacteremic pneumonia, compared with 11.4% of bacteremic episodes from other sources (P< .001). Thirty patients received ceftazidime and 10 patients received imipenem as the beta-lactam component of the initial empirical treatment. All strains of P. aeruginosa were susceptible to both agents. Forty-seven percent of streptococcal strains were penicillin resistant and showed a decreased susceptibility to ceftazidime (minimum inhibitory concentration ranged from 1 to 64 microg/mL). Five patients (12.5%) were considered to have received inappropriate empirical antibiotic therapy. Attributable mortality in patients with bacteremic pneumonia was higher than in patients with bacteremia from other sources; 22 (55%) of the 40 patients with bacteremic pneumonia died, whereas 39 (10.6%) of the 368 patients with bacteremia from other sources died (P<.001). CONCLUSIONS: Our data suggest that bacteremic pneumonia in neutropenic cancer patients is associated with a poor outcome and that empirical antibiotic therapy for neutropenic patients with pneumonia should include agents active against both P. aeruginosa and cephalosporin-resistant streptococci.     

An economic analysis of teleconsultation in otorhinolaryngology

Meningococcal sepsis is a good model to study the dynamic response of cytokines and other soluble factors in vivo in the early stages of the disease. Levels of soluble CD14, interleukin-6 (IL-6), IL-6 receptor (IL-6R), and C-reactive protein (CRP) have been measured in plasma from 26 children with septic shock (nine of whom had disseminated intravascular coagulation) and from ten control children. All samples were collected at the onset, before treatment, and, when possible, 24 and 48 hours later. At admission, patients had significantly higher levels of IL-6 (p < 0.001) and CRP (p < 0.001), and lower levels of IL-6R (p < 0.005) than normal controls. After 24 hours, there was a significant increase of sCD24 (p < 0.05) and CRP (p < 0.001). Although IL-6 showed a progressive decline since the onset, its levels were always higher than controls. There was an inverse correlation between IL-6 and both IL-6R (p < 0.001) and CRP (p < 0.001), probably due to the later increase of CRP. Nevertheless, sCD14 did not correlate with IL-6 levels. We have confirmed the finding of IL-6 as a sensitive and reliable inflammatory marker in septic shock. Moreover, the ratio IL-6/IL-6R may have a prognostic value, given a putative role of IL-6R in modulating the effects of IL-6 in meningococcal sepsis.     

Tumor necrosis factor, interleukin-2, and interferon-gamma in adult varicella

Adult varicella can be a severe illness complicated by pneumonia, encephalitis, or prolonged fever. This study measured levels of tumor necrosis factor (TNF)-alpha, interleukin-2 (IL-2), and interferon gamma (IFN-G) in a consecutive group of 31 adult varicella patients presenting within 24 hours of rash onset. All cytokines were assayed using an ELISA technique. TNF-alpha was detectable in 71% of patients with a mean level of 52 pg/ml. IL-2 was detectable in 29% with a mean level of 1040 pg/ml. IFN-gamma was detectable in only 9%. There was no correlation between TNF, IL-2, or IFN-G level and clinical severity as determined by duration and severity of cutaneous findings, duration of fever, frequency of hepatitis, or thrombocytopenia.     

Cytokines in vitreous humor: interleukin-6 is elevated in proliferative vitreoretinopathy

PURPOSE: To measure the levels of interleukins (IL) 1 beta, 6, and 8, and tumor necrosis factor-alpha (TNF alpha) in the vitreous of patients with proliferative vitreoretinopathy (PVR), proliferative diabetic retinopathy (PDR), vitreous hemorrhage, and macular pucker. METHODS: Vitreous samples were collected, undiluted, from patients with PVR, PDR of varying severity, and miscellaneous lesions (vitreous hemorrhage from trauma, macular degeneration, vein occlusion, and non-PVR patients with giant tear, retinal detachment, and macular pucker). Immunoreactive levels of the cytokines, IL-1 beta, IL-6, IL-8, and TNF alpha were determined by enzyme-linked immunoadsorbent assays, and samples were analyzed for protein and hyaluronic acid content using standard assays. RESULTS: The levels of TNF alpha were below detection limits of the assay (< 3 pg/ml). In 45 of the 47 samples tested, IL-1 beta levels also were below detection limits of the assay (< 3 pg/ml). IL-6 levels ranged from < 30 to 5487 pg/ml, with the highest values observed in the PVR patients. IL-8 levels ranged from < 20 to 1900 pg/ml, and were consistently high in the miscellaneous group. Some of the PVR patients with C2 and C3 level severity also exhibited IL-8 levels exceeding 100 pg/ml. In a second study, IL-6 content of vitreous from miscellaneous and PVR patients was compared. In this study, significantly elevated levels of IL-6 were observed in the PVR patients (91.5 +/- 18 pg/ml) compared to the miscellaneous group (10.3 +/- 3.7 pg/ml) CONCLUSIONS: Elevated levels of IL-6 in the vitreous occur in PVR, implicating a role for this cytokine in the pathogenesis of this ocular disorder.     

Long-term follow-up study of vigabatrin in pretreated children with West syndrome

The purpose of this study was to test the comparative efficacy and toxicity of empiric gentamicin and ciprofloxacin, in combination with piperacillin, in febrile patients with treatment-induced neutropenia. Fifty patients were prospectively randomized to receive piperacillin plus gentamicin (PG), and 46 were randomized to receive piperacillin plus ciprofloxacin (PC). The groups were similar in age, sex, diagnosis, duration of neutropenia, and incidence of positive cultures. The two antibiotic regimens were associated with comparable rates of defervescence in the patients with gram-positive bacteremia. In the patients with gram-negative bacteremia and those with negative cultures, however, defervescence was more prompt in the PC group. In particular, 27% of the culture-negative patients on PC, compared to only 5% of those on PG, defervesced within 72 hr (P = 0.015). Because of the more prompt defervescence in the PC group, amphotericin B was used less frequently; 78% of the patients on PG compared with only 56% of those on PC were started on amphotericin B (P = 0.025). PC is an effective alternative to the more traditional PG for treatment of febrile neutropenic hosts who have not been given prophylactic quinolones. More important, PC appears to hasten defervescence compared with PG, especially in culture-negative patients and those with gram-negative bacteremia, and may decrease the necessity of additional antimicrobial agents such as amphotericin B.     

Predicting upper limb recovery after stroke: the place of early shoulder and hand movement

We describe a rare case of pleomorphic type of malignant fibrous histiocytoma (MFH) in the buttock that presented a systemic involvement. The case was of a 58-year-old woman presenting hepatic dysfunction and inflammatory reactions including fever, positive C-reactive protein (CRP), an elevated erythrocyte sedimentation rate, and high levels of platelets and ferritin. The fever of 3 months duration subsided on the first postoperative day. The MFH resection also brought rapid normalization in CRP, platelets, and leukocytes. The local and systemic productions of cytokines induced by this tumor were evaluated. In vivo and in vitro production of interleukin (IL)-6, IL-1beta, and tumor necrosis factor alpha by tumor cells were measured using enzyme-linked immunosorbent assay. Blood samples taken preoperatively, tumor tissues, and the primary culture medium showed extraordinarily high IL-6 levels. The plasma IL-6 level was normalized postoperatively. Immunohistochemistry showed the positivity of tumor cells for IL-6. The IL-6 produced by the tumor was concluded to have been responsible for the systemic illness.     

血清半乳甘露聚糖检测对血液病患者侵袭性曲霉菌感染早期诊断的价值

目的 评价血清半乳甘露聚糖(GM)检测对血液病患者侵袭性曲霉菌(IA)感染早期诊断的价值.方法 前瞻性采用酶联免疫吸附试验(ELISA)每周2次测定患者的GM水平,并计算该诊断试验的各项评价指标.结果 共有来自92例患者的113例次感染进入研究,检测血清标本472份,以确诊IA感染和临床诊断IA感染为真阳性组,排除IA感染为真阴性组,0.7为阈值,连续2次GM结果阳性为真阳性,该诊断试验的敏感度为83.3%,特异度为91.1%,阳性预测值为78.9%,阴性预测值为93.1%.GM阳性结果较痰培养阳性时间提前4 d(1～7 d),比影像学改变提早7 d(1～14 d),较抗真菌治疗提前6 d(1～15 d).结论 通过ELISA方法进行血清GM检测可以快速、灵敏的为早期诊断IA感染提供有力证据.     

C-reactive protein serum level is a valuable and simple prognostic marker in non Hodgkin's lymphoma

Interleukin-6 plays a central role in normal B-cell maturation and in proliferation of some B-cell malignancies including multiple myeloma and some non Hodgkin's lymphomas (NHL). Furthermore, this cytokine also plays a major role in acute phase response by mediating synthesis of acute phase proteins such as C-reactive protein (CRP). In order to evaluate the exact role of CRP serum level as a simple prognostic factor, we analyzed CRP and IL-6 serum levels in 39 patients with NHL. Eleven patients had low grade NHL, 15 intermediate grade NHL, and 13 high grade NHL. Thirty percent of the patients presented detectable IL-6 serum levels (mean+/-SD: 33.6+/-95.2 U/ml, range: 0 to 500). Increased serum CRP levels were found in 42% of the patients with a mean of 29.2+/-41.97 mg/l] (range: 0 to 129). Thirty seven patients were studied for both markers. Three groups of patients were determined. One with low IL-6 and CRP serum levels (N=21), a second with high level of both markers (N=10), and the third with high serum CRP levels alone (N = 5). Only one patient had high level of serum IL-6 with no detectable CRP. The correlation of serum IL-6 and CRP levels with patient survival was investigated. Median survival in the group with low IL-6 level was not reached. 67% of patients of this group were still alive at 32 months from diagnosis. The group of patients with detectable IL-6 had a median of survival of 12 months (p<0.025). The survival of patients with a CRP<10 mg/l was not reached. 75% of patients survive at 32 months from diagnosis, whereas the group with higher CRP level reached a median survival at 8.5 months (p<0.009). As expected, on univariate analysis, there is a significant relationship between CRP and IL-6 levels (p<0.00017), and CRP levels and B symptoms (p<0.001). Furthermore there is a significant relationship between CRP and LDH levels (p<0.042).These results indicated that CRP may be considered as a valuable and easy prognostic biomarker of NHL.     

Limulus amebocyte lysate assay for detection of endotoxin in patients with sepsis syndrome. AMCC Sepsis Project Working Group

Clinical predictions alone are insufficiently accurate to identify patients with specific types of bloodstream infection; laboratory assays might improve such predictions. Therefore, we performed a prospective cohort study of 356 episodes of sepsis syndrome and did Limulus amebocyte lysate (LAL) assays for endotoxin. The main outcome measures were bacteremia and infection due to gram-negative organisms; other types of infection were secondary outcomes. Assays were defined as positive if the result was > or = 0.4 enzyme-linked immunosorbent assay units per milliliter. There were positive assays in 119 (33%) of 356 episodes. Assay positivity correlated with the presence of fungal bloodstream infection (P < .003) but correlated negatively with the presence of gram-negative organisms in the bloodstream (P = .04). A trend toward higher rates of mortality in the LAL assay-positive episodes was no longer present after adjusting for severity. Thus, results of LAL assay did not correlate with the presence of bacteremia due to gram-negative organisms or with mortality after adjusting for severity but did correlate with the presence of fungal bloodstream infection.     

Immunoglobulin A-specific capture enzyme-linked immunosorbent assay for diagnosis of dengue fever

Dengue fever (DF) is usually diagnosed by testing for dengue virus immunoglobulin M (IgM) by a capture enzyme-linked immunosorbent assay (ELISA) (MAC-ELISA). However, IgM can last for months, and its presence might reflect a previous infection. We have tested the use of anti-dengue virus IgA capture ELISA (AAC-ELISA) for the diagnosis of DF by comparing the results of MAC-ELISAs and AAC-ELISAs for 178 serum samples taken from patients with confirmed cases of DF. IgM appears more rapidly (mean delay of positivity, 3.8 days after the onset of DF) than IgA (4.6 days) but lasts longer; the peak IgA titer is obtained on day 8. The specificity and the positive predictive value of AAC-ELISA are 100%; its sensitivity and negative predictive value (NPV) are also 100% between days 6 and 25 after the onset of DF, but they decrease drastically when data for tests conducted with specimens from the first days of infection are included, because the IgA titers, like the IgM titers, have not yet risen. AAC-ELISA is a simple method that can be performed together with MAC-ELISA and that can help in interpreting DF serology.     

Serum interleukin-6 in relation to acute-phase reactants and survival in patients with renal cell carcinoma

Patients with malignancies often present with signs of inflammatory reactions such as elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). Since interleukin-6 (IL-6) is a possible regulator of these reactions and has been proposed as a predictor of prognosis, the aim of the study was to analyse its clinical significance in patients with renal cell carcinoma. Serum samples were collected from 196 patients before any treatment. IL-6 was analysed by an enzyme-linked immunoassay and compared with tumour grade, stage, acute-phase reactants and survival. Patients with renal cell carcinoma had significantly higher IL-6 levels (mean 28.1 +/- 63.4 ng/l; median 8.3 ng/l) compared with controls (mean 1.7 +/- 2.6 ng/l; median 0.5 ng/l; P < 0.001). Serum IL-6 levels in patients with distant metastases were significantly higher than for patients with tumours confined to the kidney (P = 0.02). This difference was more pronounced when serum IL-6 levels in patients with poorly differentiated tumours were compared with well-differentiated tumours (P < 0.001). A significant correlation between the acute-phase reactants CRP, ESR and IL-6 levels was found. Survival time was significantly shorter (P = 0.001) for patients with IL-6 levels above the median serum level compared with patients with lower levels. Similar significant prognostic results were obtained in the group of patients with metastatic disease, but not in group of patients with stage I-III. Serum levels of IL-6 correlated to tumour stage, grade and acute-phase reactants. Increased levels were related to the presence of metastases and adverse survival. Serum IL-6 proved univariate prognostic information but this prognostic significance was lost using a multivariate analysis.     

The false-positive rate of thoracic outlet syndrome shoulder maneuvers in healthy subjects

Cytokines are considered as mediators of immune and inflammatory responses. Cisternal CSF levels of interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1 (MCP-1) and of the soluble adhesion molecule E-selectin were evaluated in patients operated on for intracranial aneurysms. Cisternal CSF samples were obtained at surgery in 41 selected patients (31 with diagnosis of subarachnoid hemorrhage (SAH) and 10 control patients operated on for incidental unruptured aneurysms); 14 patients were operated within 72 h after SAH (early surgery) and 17 were operated after day 10 after the hemorrhage (delayed surgery). The CSF levels of cytokines were evaluated using radioimmunoassay and their concentrations were related to the timing of surgery, the amount of cisternal subarachnoid blood clots and the onset of clinical and angiographical evidence of arterial vasospasm. Mean cisternal CSF levels of IL-6, IL-8 and AMCP-1 are significantly higher in samples obtained from patients early operated after SAH, while levels of E-selectin were below the threshold value of the method in all 41 cases. In the early operated group 7 patients presented symptomatic vasospasm: levels of IL-8 and MCP-1 were not significantly different were compared to those of uncomplicated cases; on the other hand, significantly higher levels of IL-6 were shown in the subgroup of patients operated within 72 h after SAH and developing vasospasm. Among the patients undergoing delayed surgery 5 presented symptomatic vasospasm, but no significant difference was shown in cisternal CSF levels of cytokines measured. The results of the present study show that in patients with unruptured aneurysms cytokines are present in cisternal CSF in scarce quantities and that in subarachnoid spaces after SAH there is an impressive increase of IL-6, IL-8 and MCP-1. Moreover, the higher cisternal CSF levels of IL-6 found in the early stage after SAH might have a predictive value regarding the occurrence of symptomatic vasospasm.