Human cytomegalovirus, human herpesvirus-6 and human herpesvirus-7 in neutropenic patients with fever of unknown origin.

OBJECTIVE: To investigate the appearance of cytomegalovirus (CMV) DNA, human herpesvirus-6 (HHV-6) DNA and human herpesvirus-7 (HHV-7) DNA in plasma as a sign of reactivation and possible causes of fever of unknown origin (FUO) during neutropenia. METHODS: From 134 patients with febrile neutropenia following cytotoxic chemotherapy during the years 1996-2000, 20 severely neutropenic patients (granulocyte count < 0.1 x 109/L) were selected. Ten were patients with bacteremia and ten were patients with FUO. Five samples from each patient were selected at the start of chemotherapy, at the time of blood culture and fever, after 24 and 48 hours of fever, and, finally, after two to three days without fever. Virus DNA was detected by real-time quantitative and nested polymerase chain reaction (PCR). RESULTS: CMV-DNA was detected in two out of ten FUO-patients in all samples drawn during fever. From another FUO and during two bacteremia episodes, CMV-DNA was detected after 48 hours of fever. DNA from HHV-6 and HHV-7 was not detected in any of the 20 febrile episodes. CONCLUSIONS: HHV-6 and HHV-7 as a possible explanation for FUO in severely neutropenic patients treated with cytotoxic chemotherapy seems not be very likely. However, CMV was identified in 5/20 patients and the febrile episodes in the two FUO-patients with constant DNA-emia may have been caused by a reactivation of CMV. This implies that CMV infection can be expected not only in transplant patients but also in chemotherapy-treated neutropenic patients.

Activation of granulocytes in patients treated with chemotherapy.

It is well known that patients with granulocytopenia due to chemotherapy are susceptible to life-threatening infections. To determine whether or not granulocyte function is also impaired by chemotherapy, respiratory burst, CD11b and CD18 expression were analysed by flow cytometry in granulocytes from 10 patients with haematological malignancies: before and after the commencement of high-dose chemotherapy and in the recovery phase. As a comparison, the same granulocytic functions were analysed in patients treated with low-dose hydroxyurea and in healthy volunteers. The granulocytes were activated by Staphylococcus aureus and Staphylococcus epidermidis. A decreased ability to mobilize CD18 in the recovery phase was seen, but the significance of this finding must be evaluated carefully owing to the small patient number.

Increased incidence of bacteraemia due to viridans streptococci in an unselected population of patients with acute myeloid leukaemia.

The aetiology, clinical characteristics and outcome of bacteraemia in patients with acute myeloid leukaemia were studied. All positive blood cultures collected at a haematological ward during 2 7-y periods were evaluated. Altogether, 274 episodes of bacteraemia in 152 patients were recorded, 80 episodes during 1980-86 and 194 during 1990-96. During the 2 periods, trimethoprim-sulfamethoxazol in combination with amikacin was the first-line empirical therapy in patients with neutropaenia and fever. In 1990, antimicrobial prophylaxis with ciprofloxacin and fluconazole was introduced. The incidence of bacteraemia due to viridans streptococci or coagulase-negative staphylococci increased from the first period to the second, whereas the incidence of Enterobacteriaceae decreased. In granulocytopaenic patients during 1990-96, viridans streptococci accounted for 21% of the isolates and in patients treated prophylactically with fluoroquinolone, viridans streptococci accounted for 31%. All viridans streptococci were sensitive to penicillin. At the time of the positive blood cultures, the patients of the second period were granulocytopaenic in 83% of the episodes. The mortality related to septicaemia during the later period was 13% and only 1 of 33 (3%) of the patients with viridans streptococci died. Eight patients (9%) died in relation to septicaemia following curative antileukaemic therapy.

Adhesion molecules (E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1)) in sera from patients with Staphylococcus aureus bacteraemia with or without endocarditis.

The aim of this prospective study was to evaluate if patients with endocarditis display a more extensive endothelial activation than those with bacteraemia but without endocarditis. Sixty-five patients with blood culture-verified Staphylococcus aureus bacteraemia were included and serum samples collected on admission were analysed by enzyme immunoassays. Elevated serum concentrations of adhesion molecules were found in most of the patients with S. aureus bacteraemia. Patients with endocarditis (n = 15) showed significantly higher serum E-selectin (median 156 ng/ml) and VCAM-1 (median 1745 ng/ml) concentrations compared with those with S. aureus bacteraemia but without endocarditis (80 ng/ml and 1172 ng/ml, respectively; P = 0.01 and P = 0.003). No significant difference was found between the groups concerning ICAM-1 (median 451 ng/ml versus 522 ng/ml). In addition, serum tumour necrosis factor-alpha (TNF-alpha) concentrations were significantly correlated (P < 0.002) to serum levels of E-selectin, ICAM-1 and VCAM-1.

Cytokine responses in patients with pneumonia caused by Chlamydia or Mycoplasma.

The serum concentrations of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) were measured by enzyme immunoassays in 44 patients with Chlamydia (n = 13) or Mycoplasma (n = 14) pneumonia or influenza A infection (n = 17) and in 20 control subjects. The levels of IFN-gamma were raised in 29/44 patients. The concentrations of IL-6 were raised in 32/44 patients. Raised levels of TNF-alpha were seen in 26/44 but there was no significant difference between the levels of the different groups of patients. All three cytokines indicated clinical recovery when acute and convalescent samples from 10 patients with Chlamydia pneumonia were analyzed. IFN-gamma, IL6 and TNF-alpha are present in the circulation in the majority of patients with Chlamydia and Mycoplasma pneumonia and in influenza A infection. We suggest that repeated measurement of cytokines, such as IL-6, IFN-gamma and TNF-alpha, may be useful in the management of lower respiratory tract infections but further studies are needed to define the value of cytokine measurements in acute pneumonia.

Secretion of IL-6, IL-8 and G-CSF by human endothelial cells in vitro in response to Staphylococcus aureus and staphylococcal exotoxins.

The capacity of endothelial cells to produce and release cytokines (IL-6, IL-8 and G-CSF) in response to exposure to Staphylococcus aureus strains or staphylococcal exotoxins (alpha-toxin, enterotoxin A and TSST-1) was investigated. An endothelial cell culture model of human umbilical vein endothelial cells (HUVEC) was used. Five out of ten clinical isolates of S. aureus were found to induce cytokine production and release from endothelial cells. Four of the five isolates that induce cytokine release produced enterotoxin A, B, C, D and/or TSST-1, compared with two of those that did not induce release. Purified staphylococcal exotoxins (1 pg/ml-1 microg/ml) did not act as primary stimuli and induced no detectable cytokine secretion. When endothelial cells were prestimulated with IL-1beta or TNF alpha at a concentration of 1 ng/ml for 2 h, IL-1beta served as a potent primary stimulus for IL-6, IL-8 and G-CSF production, whereas TNF alpha did not induce any significant cytokine release during the subsequent 24 h. A further increase in IL-6 and G-CSF release, but not of IL-8, was observed when IL-1beta prestimulated cells were exposed to alpha-toxin or TSST-1. However, to potentiate cytokine production (IL-6 and IL-8) by SEA, both IL-1beta and the toxin had to be present simultaneously. Our data show that S. aureus, but not staphylococcal exotoxins, have the capacity to act as primary stimuli of endothelial cells and induce production and release of cytokines. IL-1beta may prime HUVEC to release IL-6, IL-8 and G-CSF prior to subsequent stimulation with staphylococcal exotoxins.

Bacterial or crystal-associated arthritis? Discriminating ability of serum inflammatory markers.

A retrospective study of patients with culture-verified septic arthritis (n = 54) and polarizing microscopy verified crystal-associated arthritis (n = 34) was conducted with the objective to identify discriminating laboratory parameters in serum. Serum CRP levels (p = 0.002) and ESR (p = 0.03) were significantly higher on admission in patients with septic arthritis than in those with crystal-associated arthritis. The peripheral WBC counts did not differ between the two groups, nor did the lactoferrin or procalcitonin (PCT) levels. Serum TNFalpha concentrations on admission were higher in patients with septic arthritis than in those with crystal-associated arthritis (p = 0.0008). Significant differences were also found for IL-8 (p = 0.01) and G-CSF (p = 0.002), but not for IL-6 (p = 0.5). However, extensive overlap between the groups was present, resulting in low sensitivity, specificity and predictive value for each test. Determining serum levels of acute phase reactants, including cytokines, does not replace careful synovial fluid examination, including direct microscopy and cultivation.

A fatal case of Listeria endocarditis in a man following his tending of goats suggests an epidemiological link which is not supported by the results.

A man died in endocarditis due to listeriosis in the late autumn. He had been looking after two goats during the summer. Listeria monocytogenas was isolated from a rectal swab from one of the goats. The goat faeces isolate and the human blood isolate were of identical serovar. The two isolates, however, were shown to be different by multilocus electrophoretic enzyme analysis and ribotyping, as well as by biotyping. Thus, these results do not support the hypothesis that the man was infected by the goat.

One bolus dose of gentamicin and early oral therapy versus cefotaxime and subsequent oral therapy in the treatment of febrile urinary tract infection.

The efficacy and safety of two different regimens for parenteral treatment of presumed severe febrile urinary tract infection were compared in a randomized study. One hundred fifty-eight patients were treated with either cefotaxime 2 g i.v. twice daily for at least two days followed by norfloxacin 400 mg twice daily orally or one bolus dose of gentamicin 3 mg/kg i.v. and norfloxacin from the start. Three patients randomized to cefotaxime died. Of the 101 patients with verified urinary tract infection, clinical response to assigned therapy was seen in 79% and 74%, respectively. There was no difference in fever duration between the two regimens. The results indicate that one bolus dose of gentamicin with early oral therapy is a safe and effective alternative to common parenteral regimens for empirical treatment of febrile urinary tract infection.

Dynamics of blood cytokine concentrations in patients with bacteremic infections.

Cytokines play a major role in the pathophysiology of sepsis and septic shock. Using enzyme immunoassays the acute serum levels of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), granulocyte-colony stimulating factor (G-CSF), interleukin-8 (IL-8), and leukemia inhibitory factor (LIF) were investigated in 90 patients with positive blood cultures and clinical signs of infection. In 27 patients samples were obtained on admission, after 1, 4, 12, 18, and 24 h, and then daily. The acute serum levels of IL-6, TNF-alpha, G-CSF, and IL-8 were significantly higher among patients with severe sepsis. Patients with Gram-negative infection had significantly higher levels of TNF-alpha on admission than did patients with Gram-positive infections (p = 0.0008). The levels of IL-6, G-CSF and, to some extent, TNF-alpha decreased rapidly in survivors within the first 24 h of admission to hospital and institution of treatment. LIF was detected in 8/90 in both survivors and nonsurvivors.

Diagnostic value of blood cytokine concentrations in acute pneumonia.

BACKGROUND: The role of cytokines in the pathogenesis of pneumonia is still poorly understood. In a previous study the diagnostic value of measuring blood concentrations of interleukin 6 and interferon gamma was established. In the present study the value of blood concentrations of interleukin 8, granulocyte-colony stimulating factor, and lactoferrin as markers of bacteraemic pneumonia is evaluated. METHODS: The circulating concentrations of interleukin 8 (IL-8), granulocyte-colony stimulating factor (G-CSF), and lactoferrin were measured in 14 patients with bacteraemic pneumococcal pneumonia and 49 patients with atypical pneumonia or influenza A infection using enzyme immunoassays. RESULTS: Serum G-CSF concentrations were higher in the group with bacteraemic pneumococcal pneumonia, and G-CSF values correlated with the white blood cell count and levels of C-reactive protein (CRP). The levels of IL-8 were higher in the group with bacteraemic pneumococcal pneumonia than the groups with Chlamydia pneumonia, Legionella pneumonia, or influenza A infection, but there was no difference when compared with the group with Mycoplasma pneumonia. A white blood cell count of > 15 x 10(9)/l was highly suggestive of bacteraemic pneumonia. The concentrations of lactoferrin were raised in all groups except those with influenza A infection, but no difference was found between the different aetiological groups. A correlation was found between lactoferrin and white blood cell counts. CONCLUSIONS: Serum G-CSF and IL-8 concentrations are potential markers of bacteraemic pneumonia.

Invasive Haemophilus influenzae disease: epidemiology and clinical spectrum before large-scale H. influenzae type b vaccination.

In a prospective study between January 1987 and December 1992, 103 patients with invasive Haemophilus influenzae (Hi) infection were identified in a well-defined population before large-scale Haemophilus influenzae type b (Hib) vaccination was introduced. The incidence (case/100,000/year) of invasive Hi infection was 5.9 for the whole population, 55 for children 0-4 years old and as high as 2.8 for adults. Hib was the predominant cause of the infection (83 cases) in children but, in adults, 13/39 (30%) cases were caused by non-typable Hi and 6/39 (19%) by Hi serotype f. Three patients (3%) died and 6 (5.8%) suffered a permanent sequel from the infection. All patients with such a sequel had invasive Hib infection. No significant difference between patients 0-6 years old and matched controls regarding the frequency of subnormal serum levels of immunoglobulins was found.

Serum concentrations of interleukin-6, tumour necrosis factor-alpha, and C-reactive protein in patients undergoing major operations.

OBJECTIVE: To investigate the kinetics of interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha) and C-reactive protein after a surgical operation. DESIGN: Prospective study. SETTING: Teaching hospital, Sweden. SUBJECTS: 28 patients undergoing cardiac operations, joint replacement, or gastric restrictive operations. INTERVENTIONS: Samples of serum were taken before operation; at 0, 6, and 12 hours; and then daily for six days. OUTCOME MEASURES: IL-6, TNF-alpha, and C-reactive protein concentrations at specified time points, and their correlation with complications and outcome. RESULTS: The IL-6 concentration peaked soon after operation, and that of C-reactive protein 48-96 hours later. Serum IL-6 concentrations were highest in the eight patients undergoing cardiac operations. In one patient an infective complication occurred resulting in secondary peaks of IL-6 and C-reactive protein. Three patients who developed postoperative circulatory and respiratory instability had no additional changes in cytokine concentrations. The overall concentrations of IL-6 were raised above 100 pg/ml for a mean of 36 hours after operation and those of C-reactive protein were over 100 mg/l for a mean of 106 hours (p < 0.0001). Serum TNF-alpha concentrations were low in all patients. CONCLUSION: The maximum serum concentrations of IL-6 and C-reactive protein after surgical operations were comparable to those in patients with sepsis. If IL-6 and C-reactive protein analyses are used in the diagnosis of infective complications, evaluation of the results should be related to the length of time between the operation and sampling, and to the clinical findings. The shorter period during which IL-6 was raised compared with C-reactive protein indicates that IL-6 may be a more useful marker of postoperative infective complications.

Interleukin-6, C-reactive protein, lactoferrin and white blood cell count in patients with S. aureus septicemia.

In a prospective study of 65 patients with S. aureus septicemia, the clinical value of measuring serum IL-6 and lactoferrin levels was assessed and compared with CRP levels and WBC count. 20/65 (31%) patients had a CRP value < or = 100 mg/l on admission and 10 (50%) and 11 (55%) of these had serum levels of IL-6 > 100 pg/ml or lactoferrin > 2.0 mg/l, respectively. 41/64 (64%) patients had a WBC count < or = 15.0 x 10(9)/l and the corresponding figures for increased IL-6 and lactoferrin values were 29 (71%) and 21 (51%) patients, respectively. The high concentrations of IL-6 and lactoferrin on admission decreased rapidly during the hospital stay, better reflecting the clinical course than CRP and WBC count. Patients with endocarditis showed higher IL-6 levels and body temperatures both on admission and during the first days of hospitalization compared with patients without endocarditis.

Fluconazole failure in two cases of disseminated candidosis.

Amphotericin B has been the standard treatment of disseminated candidosis although the less toxic fluconazole tends to be used more frequently. In a recent report, no significant difference in the efficacy of candidaemia treatment was observed between fluconazole and amphotericin B. However, we report on 2 cases of invasive candidosis where fluconazole failed to eradicate Candida albicans although the isolates were susceptible to fluconazole in vitro. Pulsed-field gel electrophoresis was used to confirm the persistence of the same C. albicans strain after therapy failure in both patients.

Serological response in leprosy and tuberculosis patients to the 18-kDa antigen of Mycobacterium leprae and antigen 85B of Mycobacterium bovis BCG.

Two enzyme-linked immunosorbent assays (ELISAs) for the detection of leprosy antibodies were developed. These assays were based on the recombinant 18-kDa protein of Mycobacterium leprae and the 85B antigen of M. bovis. Sera from leprosy and tuberculosis patients were analyzed, and a phenolic glycolipid-I (PGL-I) ELISA was used as a reference test. The 18-kDa ELISA reached a sensitivity of 70% on lepromatous leprosy sera. The corresponding results for the 85B and the PGL-I ELISAs were 93% and 96%, respectively. The sensitivity on tuberculoid leprosy sera was 72% for the 18-kDa antigen, 95% for the 85B antigen, and 60% for the PGL-I antigen. The 18-kDa antigen ELISA was found to have crossreactivity to sera from patients with tuberculosis, while the 85B and PGL-I assays had high specificity.

Deep obstetrical and gynecological infections caused by non-typeable Haemophilus influenzae.

Six patients with deep obstetrical and gynecological infections due to non-typeable Haemophilus influenzae are presented. 3 patients had tubo-ovarian abscesses, 2 septic abortions and 1 postpartum sepsis. All our patients with tubo-ovarian abscesses had used intra-uterine contraceptive devices until admission and all had a protracted course of illness. Both patients with septic abortion had a severe course, one of them with disseminated intravascular coagulation demanding treatment in the intensive care unit. The patient with postpartum infection had a milder course. The possibility of infection with H. influenzae and the emergence of beta-lactamase producing strains warrant adequate culture procedures in women with obstetrical and gynecological infections in order to ensure proper treatment.

Mapping of T helper cell epitopes by using peptides spanning the 19-kDa protein of Mycobacterium tuberculosis. Evidence for unique and shared epitopes in the stimulation of antibody and delayed-type hypersensitivity responses.

In vivo and in vitro T cell responses to overlapping 20-mer peptides that span the entire 19-kDa protein of Mycobacterium tuberculosis have been compared in three different strains of mice. Immunization of the mice with peptides and analysis of specific antibody production is an in vivo assay of Th cell activity. Peptides 1-20 and 61-80 elicited strong IgG1 responses in BALB/cJ, C57BL/10J, and B10.BR mice, indicating that these peptides could stimulate Th cells, possibly of a Th2 phenotype. T cells isolated from peptide-immunized mice were challenged in vitro with peptide, and their proliferative responses were analyzed. T cells from these three strains of mice immunized with peptides 1-20, 61-80, and 76-95 also responded to challenge with specific peptide in vitro. In addition, B10.BR mice and BALB/cJ mice showed antibody and T cell proliferative responses to peptides 136-155 and 145-159, respectively. Thus, in vitro proliferating T cells were found to possess specificities for peptide epitopes that were almost identical to those of the antibody-producing cells. Delayed-type hypersensitivity (DTH) responses to these peptides were also examined in the three strains. Interestingly, the T cells responding in the DTH assay had Ag specificities that were quite different from those identified in the antibody and proliferation assays. These results suggested that DTH Th cells form a separate population from antibody Th and proliferative T cells and these populations of cells were differentially activated, in an Ag-specific manner.

Kinetics of serum levels of interleukin-6 in Staphylococcus aureus septicemia.

The kinetics of Il-6 serum concentrations were analyzed in 17 patients with a culture verified Staphylococcus aureus septicemia. The analyses were performed using an antigen capture immunoassay. All patients had elevated IL-6 serum concentrations on admission. In most cases a subsequent rapid decrease to low levels was registered within 10 days. The IL-6 serum concentrations reflected the clinical course. In sera sampled on admission a relationship was found between IL-6 serum concentrations and levels of C-reactive protein.