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J T van Dissel

Publications and source records attributed to J T van Dissel.

At least 73 records · Page 4Linked to original sources
PubMed1998

Streptococcus pneumoniae, an emerging pathogen in mycotic aneurysms?

Two patients are described with a mycotic aneurysm caused by streptococcus pneumoniae infection. The patients presented with back pain and fever, and had an antecedent history of lower respiratory tract infection; neither of them were suffering from endocarditis. Mycotic aneurysms are a rare disorder with, over the years, a changing spectrum of presentation, localisation and bacterial aetiology. S. pneumoniae infection has only very rarely been reported as a cause of mycotic aneurysms. Since 1986, 14 patients with a mycotic aneurysm were treated at the Leiden University Hospital. Of these patients, 5 had mycotic aneurysms caused by S. pneumoniae infection. The mortality in these patients was high. In this communication, we would like to draw attention to S. pneumoniae infections as an emerging cause of mycotic aneurysms.

Aged↗
PubMed1998

Antibiotic-induced release of lipoteichoic acid and peptidoglycan from Staphylococcus aureus: quantitative measurements and biological reactivities.

Antibiotics with different mechanisms of action may vary with respect to their effects on the release and immunostimulatory activities of cell wall fragments from gram-positive bacteria. Therefore, after Staphylococcus aureus was cultured for 4 h in the absence of antibiotics (control) and in the presence of beta-lactam antibiotics (imipenem, flucloxacillin, or cefamandole) and protein synthesis-inhibiting antibiotics (erythromycin, clindamycin, or gentamicin), the lipoteichoic acid (LTA) and peptidoglycan (PG) levels in the bacterial supernatants were measured. beta-Lactam antibiotics greatly enhanced the release of LTA and PG (4- to 9-fold and 60- to 85-fold, respectively), whereas protein synthesis inhibitors did not affect PG release and even inhibited the release of LTA compared to the amount of LTA released in control cultures. The capacity of beta-lactam supernatants to stimulate the production of tumor necrosis factor alpha and interleukin-10 in human whole blood was significantly higher than that of protein synthesis inhibitor or control supernatants; the amounts of these cytokines released were directly proportional to the concentrations of PG and LTA in the supernatants. Enzymatic degradation of PG in the supernatants indicated that PG was mainly responsible for the observed biological reactivity.

Anti-Bacterial Agents↗
PubMed1998

Antibiotic-induced lipopolysaccharide (LPS) release from Salmonella typhi: delay between killing by ceftazidime and imipenem and release of LPS.

It has been suggested that the antibiotic-induced release of lipopolysaccharide (LPS) is an important cause of the development of septic shock in patients treated for severe infections caused by gram-negative bacteria. Beta-lactam antibiotics change the integrity of the bacterial cell envelope by binding to penicillin-binding proteins (PBP) in the membrane and thus may affect the amount of LPS that is released and the kinetics of that release. In this respect, ceftazidime at intermediate concentrations binds with a high affinity to PBP 3 and PBP 1a and thus can induce filament formation in addition to killing, whereas imipenem preferentially binds to PBP 2 and PBP 1b, leading to spheroplast formation and rapid cell lysis. We investigated the effects of these antibiotics on the killing and the release of the radioactively labelled LPS of Salmonella typhi Ty 21A. A mathematical model was developed to calculate the delay between bacterial killing and LPS release, designated the lag time. At antibiotic concentrations inducing equal killing, the amount of LPS released was the same for both antibiotics. Only after 6 h of incubation at antibiotic concentrations above 0.5 microg/ml, the amount of 3H-LPS released was slightly higher (approximately 1.2-fold) in incubations with ceftazidime than in those with imipenem, and the maximum releases of the total label were 33.2% +/- 0.89% and 27.1% +/- 0.45%, respectively. Despite the clear concentration-dependent effect on the bacterial killing and subsequent LPS release, the lag time was independent of the antibiotic concentration. For ceftazidime as well as imipenem the lag time amounted to approximately 60 min. In conclusion, our findings imply that the mechanism of antibiotic-induced LPS release is independent of the PBP affinities for these beta-lactam antibiotics. Furthermore, once the organism is killed by either imipenem or ceftazidime, the rate of LPS release from S. typhi does not differ according to the antibiotic with which the organism is killed, and there is little difference in the relative amount of LPS released.

Anti-Bacterial Agents↗
PubMed1997

[Ophthalmic preparations Polyspectran (combination of neomycin, polymyxin B and bacitracin/gramicidin) and Terramycin (oxytetracycline with polymyxin B) mistakenly no longer reimbursed].

The Netherlands' Ministry of Health and the health insurance companies have drawn up a list of preparations which will no longer be reimbursed. The ocular antibiotic preparations Polyspectran and Terramycin are on the list. However, there are no satisfactory alternative with respect to the broadness of the antibiotic spectrum required. In addition, some alternatives have serious side effects or may induce bacterial resistance.

Anti-Bacterial Agents↗
PubMed1997

Antibody response to Haemophilus influenzae type b vaccine in relation to the number of CD4+ T lymphocytes in adults infected with human immunodeficiency virus.

A prospective study of antibody production by adults infected with human immunodeficiency virus (HIV) after vaccination with tetanus toxoid-conjugated Haemophilus influenzae type b (Hib) vaccine was conducted. Concentrations of antibodies to the two immunogenic components of the vaccine (i.e., polyribosylribitolphosphate [PRP] and tetanus toxin) were determined. Individuals were divided into three groups according to the CD4+ T lymphocyte count: group 1, < or =100 x 10(6)/L; group 2, 101-300 x 10(6)/L; and group 3, >300 x 10(6)/L. After vaccination, concentrations of IgM and IgG antibodies to PRP were significantly lower in group 1 than in the other patient groups and controls. A CD4+ T lymphocyte count of <100 x 10(6)/L and an impaired proliferative response of lymphocytes to monoclonal antibody to CD3 were independently associated with a less than threefold increase in concentrations of IgG antibody to PRP. Analysis of IgG subclasses demonstrated that the production of IgG1 antibodies was predominantly affected. Postvaccination concentrations of antibody to tetanus toxin were significantly lower in group 1 than in group 3 and controls. Both prevaccination and postvaccination concentrations of antibody to tetanus toxin were not correlated with the magnitude of the response of antibody to PRP. We conclude that HIV-infected individuals with CD4+ T Iymphocyte counts of <100 x 10(6)/L demonstrate an impaired antibody response after vaccination with conjugated Hib vaccine.

Adolescent↗
PubMed1997

Infectious disease complications of simultaneous pancreas kidney transplantation.

BACKGROUND: Although technical success rate of simultaneous pancreas kidney (SPK) transplantation in insulin-dependent diabetes mellitus (IDDM) patients with diabetic nephropathy has improved, morbidity remains high due to infection and rejection. The purpose of this study was to analyse infections encountered in our series of SPK transplants, using a restrictive antibiotic prophylaxis policy. METHODS: We reviewed all infectious diseases after 66 consecutive bladder-drained SPK transplantations in 64 IDDM patients with end-stage renal disease due to diabetic nephropathy. During follow-up, the perioperative antibiotic regimen was altered (from 5 days preemptive therapy with multiple drugs to 1 day prophylaxis with cefamandole), and long-term viral prophylaxis (high-dose aciclovir) was introduced. For post-operative urinary tract or opportunistic infection, no prophylaxis was given. RESULTS: Overall mean infection rate was 2.9 infections/ patient/year after a mean follow-up of 2.3 years. Surgical site infections (SSI) were seen in 30% of the patients, with Enterococci present in 47%. Logistic regression showed one day cefamandole prophylaxis to be associated with SSI, but there was no significant influence of SSI on either graft or patient survival. Forty-eight percent of all infections were lower urinary tract infections (UTI). There were 59 first UTIs (89%), probably related to long-term Foley catheter use, and 47 second UTIs (71%). Subsequent UTIs were not microbiologically related to first UTIs. Cytomegalovirus (10 patients) and other opportunistic agents did not cause mortality or graft loss. Five grafts were lost due to infection (SSI three times, post-transplant lymphoproliferative disease twice). Only one patient died because of infection (2%). CONCLUSIONS: Infectious diseases after SPK transplantation caused significant morbidity but did not influence either patient or graft survival. A change in prophylactic policy for both SSI as well as recurrent UTI, combined with earlier Foley removal, may lower incidences of these infections.

Adult↗
PubMed1997

Combination of flucloxacillin and gentamicin inhibits toxic shock syndrome toxin 1 production by Staphylococcus aureus in both logarithmic and stationary phases of growth.

Production of exotoxins by staphylococci and streptococci may lead to the development of toxic shock syndrome (TSS). Because clindamycin inhibits exotoxin production, its use has been advocated for the treatment of TSS. However, the bacteriostatic action of clindamycin might be a disadvantage for the treatment of overwhelming infections. We investigated the effects of flucloxacillin and gentamicin on exotoxin production, because incubation with these antibiotics combines bactericidal action with protein synthesis inhibition. Staphylococcus aureus during the logarithmic and stationary phases of growth was incubated with either clindamycin, flucloxacillin, or a combination of flucloxacillin and gentamicin at concentrations of 2 or 10 times the MIC. In logarithmic-phase cultures clindamycin had a static effect on bacterial growth. After incubation with flucloxacillin, either alone or in combination with gentamicin, a rapid and large reduction in the number of viable bacteria was demonstrated. In stationary-phase cultures none of the antibiotics significantly changed the number of viable bacteria. TSS toxin 1 (TSST-1) production during logarithmic-phase growth was inhibited by > or =95% by all antibiotics. In stationary-phase cultures, clindamycin, flucloxacillin, and the combination of flucloxacillin and gentamicin inhibited TSST-1 production by 95, 30, and 75%, respectively, compared with the level of exotoxin production in the controls. The present results indicate that clindamycin inhibits TSST-1 production and exerts bacteriostatic activity in both bacterial growth phases. Because the combination of flucloxacillin and gentamicin combines the inhibition of exotoxin production with high bactericidal activity at least in logarithmic-phase cultures, it should be considered an alternative to clindamycin for the treatment of exotoxin-mediated diseases, especially in patients with overwhelming infections.

Anti-Bacterial Agents↗
PubMed1996

Campylobacter jejuni peritonitis in a patient with liver cirrhosis.

A 56-year-old man with alcoholic liver cirrhosis (Child-Pugh class C), ascites and hepatocellular carcinoma developed acute diarrhoea and fever. Ascites granulocyte count was 5760 per microliters. Campylobacter jejuni grew in cultures from faeces, blood and ascites. The patient was successfully treated with erythromycin. Although the incidence of bacterial infections including peritonitis is high in patients with end-stage liver cirrhosis, this is one of very few cases in which Campylobacter jejuni has been identified as the causative microorganism.

Anti-Bacterial Agents↗
PubMed1995

Respiratory syncytial virus, a rare cause of severe pneumonia following bone marrow transplantation.

Mixed alveolar interstitial pneumonia is a much-feared complication in bone marrow transplant recipients because it carries a high mortality. Many cases in which an etiological agent is identified are due to fungi or cytomegalovirus; rarely, other infectious agents such as Pneumocystis carinii or (para)influenzavirus are involved. In this report we describe a patient who received intense chemotherapy followed by autologous bone marrow transplantation for relapse of testis seminoma and who developed a severe alveolar interstitial pneumonia caused by respiratory syncytial virus in the early posttransplant period. The patient fully recovered after treatment with ribavirin.

Adult↗
PubMed1995

Antibody response to diphtheria, tetanus, and poliomyelitis vaccines in relation to the number of CD4+ T lymphocytes in adults infected with human immunodeficiency virus.

A prospective study of antibody production by adults infected with human immunodeficiency virus (HIV) after vaccination with T lymphocyte-dependent diphtheria toxoid, tetanus toxoid, and inactivated trivalent poliovirus vaccine was conducted. Individuals were divided into three groups according to CD4+ T-lymphocyte count: group 1 had a count of < or = 100-300 x 10(6)/L; and group 3, > 300 x 10(6)/L. After vaccination, 61%, 70%, and 73% of the individuals in groups 1, 2, and 3, respectively, developed protective titers of antibody to diphtheria toxin; the mean postvaccination antibody titer of HIV-infected individuals was significantly lower than that of healthy controls not infected with HIV. Furthermore, the mean titers of antibodies to tetanus toxin and poliovirus were significantly lower in HIV-infected individuals with CD4+ lymphocyte counts of < 300 x 10(6)/L than in controls. Of the HIV-infected vaccinees, 83%-100% were protected against tetanus and 78%-100% against polio. We conclude that HIV-infected individuals with CD4+ lymphocyte counts of < 300 x 10(6)/L have an impaired (secondary) antibody response after receipt of T lymphocyte-dependent vaccines.

Adult↗
PubMed1995

Release of tumor necrosis factor: an innate host characteristic that may contribute to the outcome of meningococcal disease.

Tumor necrosis factor (TNF) plays a pivotal role in meningococcal disease. The TNF response to endotoxin, however, differs between individuals and can be determined in whole blood samples ex vivo. The release of TNF in whole blood samples from 50 survivors of meningococcal disease 6-58 months after hospital discharge was studied. The TNF response was higher in patients who had experienced a moderately severe disease course compared with patients with a mild course. The TNF response was low again in the survivors of fulminant disease, who on original hospital admission presented with risk factors exposing them to a high chance of mortality (50% overall). On admission, the patients who did not survive had initial TNF levels three times higher than those in survivors with a clinical disease presentation of similar severity. Overall interpretation of these findings is that the innate TNF response may contribute to the outcome of meningococcal disease.

Adolescent↗
PubMed1994

Anti-tumor necrosis factor antibodies inhibit the influx of granulocytes and monocytes into an inflammatory exudate and enhance the growth of Listeria monocytogenes in various organs.

This study concerns the effect of anti-tumor necrosis factor (TNF) antibodies on the course of a sterile inflammatory reaction in the peritoneum and a generalized infection with gram-positive bacteria. Mice received an intravenous injection of rabbit anti-TNF serum or normal rabbit serum 24 h before an intraperitoneal injection of heat-killed Listeria monocytogenes or an intramuscular injection of live L. monocytogenes. The course of the leukocytes in blood and the peritoneal cavity was followed for 72 h; the infection was evaluated for 144 h. The results lead to the conclusion that anti-TNF inhibits the migration of granulocytes and monocytes from bone marrow to the circulation and from the circulation to the peritoneal cavity during an acute inflammation. Furthermore, treatment of mice with anti-TNF serum enhanced the growth of Listeria monocytogenes in thigh muscle, liver, and spleen. The results of this study indicate that treatment with anti-TNF antibodies can inhibit the development of a cellular inflammatory exudate and can have a deleterious effect on the course of an infection with gram-positive bacteria.

Animals↗
PubMed1994

Antibody response to influenza, tetanus and pneumococcal vaccines in HIV-seropositive individuals in relation to the number of CD4+ lymphocytes.

OBJECTIVE: To establish when the formation of antibodies against T-lymphocyte-dependent and -independent antigens is impaired during HIV infection. DESIGN: Prospective study on antibody formation before and 30 days and 60 days after vaccination with tetravalent influenza vaccine, tetanus toxoid and pneumococcal vaccine; booster with influenza vaccine was administered 30 days after initial vaccination. SETTING: Outpatient clinic of University Hospital Leiden. PARTICIPANTS: Fifty-one HIV-infected individuals and 10 healthy controls. RESULTS: In HIV-infected individuals with < 100 x 10(6)/l CD4+ lymphocytes almost no influenza antibodies were formed; CD4+ counts between 100 and 300 x 10(6)/l correlated with suboptimal antibody formation; CD4+ counts > or = 300 x 10(6)/l yielded more individuals with protective antibody titres. Thirty days after vaccination, protective antibody titres against the four influenza strains had been achieved in 24% of all HIV-infected individuals for A/Beijing (H3N2) (controls, 90%), 59% for A/Taiwan (H1N1) (controls, 80%), 18% for B/Beijing (controls, 30%) and 37% for B/Panama (controls 90%). Booster vaccination after 1 month did not increase antibody levels. Anti-tetanus toxin antibody formation, which is also T-lymphocyte-dependent, was correlated with the number of CD4+ lymphocytes. After pneumococcal vaccination (T-lymphocyte-independent), normal antibody formation was observed in HIV-infected individuals, including those with low CD4+ counts. CONCLUSIONS: Influenza vaccination should not be administered to HIV-infected individuals with CD4+ counts < 100 x 10(6)/l; pneumococcal vaccination can be offered to all HIV-infected individuals and a tetanus toxoid booster should be administered when indicated.

Adult↗