PubMed HealthSearch

Biomedical subjects

G Linzenmeier

Publications and source records attributed to G Linzenmeier.

At least 19 recordsLinked to original sources

Evidence that sustained growth suppression of intestinal anaerobic bacteria reduces the risk of acute graft-versus-host disease after sibling marrow transplantation.

The influence of intestinal bacterial decontamination on the occurrence of grades II to IV acute graft-versus-host disease (GVHD) was retrospectively analyzed in 194 predominantly adult patients treated by genotypically identical sibling marrow transplantation under conditions of strict protective isolation and intestinal antimicrobial decontamination. Forty-five patients (23%) developed acute GVHD and univariate analysis identified four features that significantly increased the risk for this reaction: chronic myeloid leukemia as the underlying disease, as compared with all other disease categories (P < .0001); female marrow donors for male recipients, as compared with other gender combinations (P < .005); ineffective, as compared with sustained growth suppression of intestinal anaerobic bacteria (P < .006); and methotrexate as the sole immunoprophylactic compound, as compared with cyclosporine containing regimens (P < .05). Using the duration of anaerobic growth suppression as a time-dependent explanatory variable, proportional hazards regression analysis confirmed these features as independent predictors for acute GVHD with relative risk estimates of 1.9 (95% confidence interval [CI], 1.3 to 2.7) for the immunoprophylactic regimen (P < .0004), of 1.8 (95% CI, 1.3 to 2.5) for the underlying disease (P < .0005), of 1.7 (95% CI, 1.2 to 2.5) for anaerobic decontamination (P < .002), and of 1.3 (95% CI, 1.1 to 1.6) for the donor/recipient gender combination (P < .008), respectively. Best subset selection modeling also identified the quality of anaerobic decontamination as the third most important predictor for acute GVHD, when all four significant features were included. Estimates of acute GVHD stratified by the quality of anaerobic bacterial growth suppression showed a strong influence of anaerobic decontamination in patients burdened by at least one of the other unfavorable factors (P < .009). In conclusion, this study provides strong evidence that sustained growth suppression of intestinal anaerobic bacteria after clinical sibling marrow transplantation can independently modulate the occurrence of grades II to IV acute GVHD, which is in concordance with previous results from animal transplantation models. Antimicrobial chemotherapy specifically targeted to the intestinal anaerobic bacterial microflora may be complementarily useful in preventing acute GVHD and should be investigated in a prospective trial.

Adolescent

[Criteria for the establishment of limits for antibacterial chemotherapy].

The safety of patients asks for stringent standards when fixing limit values of the minimal inhibition concentration (MIC) in mg/l. It should be possible to recognize resistant bacterial strains with a low error on the basis of the recommendations of the bacteriological laboratory which are eventually important for therapy. Attention is drawn to the use of recognized methods such as DIN 58940 and 58944 and the participation in interlaboratory studies. Only such bacteria should be interpreted as "susceptible" whose MIC's are reliably below or, which is even better, much below the generally recognized average blood and tissue levels. Thus the break-points for the rating "susceptible" must be within the range of low variation. As a result, a few strains more would come within the "moderately susceptible" range. This would not exclude them from being selected if chemotherapy is performed with a correspondingly higher dosage (provided it is tolerated). Information on the chances of a success of therapy is improved in this way. A generous interpretation of pharmacokinetic data will in the end be more to the patient's detriment. In addition, there are numerous factors determining success or failure of therapy which cannot be established in vitro so that it is advisable to fix laboratory parameters in a stringent manner like that applied in the annexes (evaluation steps) to parts 3 and 4 of DIN 58940.

Anti-Bacterial Agents

Bone marrow transplantation in acute leukemia.

In Essen 142 bone marrow transplantations were carried out between December 1975 and February 1985. In 74 cases the indication was acute leukemia in relapse (n = 23) or in first or consecutive remission (n = 51). The conditioning regimen consisted of cyclophosphamide or the combination of cyclophosphamide and total body irradiation. All patients were treated under strict gnotobiotic care. To mitigate the risk of CMV infections, intravenous CMV-hyperimmune globulin and CMV-negative blood products have been applied routinely for 2 years. MTX was used as prophylaxis against GvHD. In the prognostically unfavorable group of acute leukemia in relapse, only one patient showed long-term survival. In this patient, leukemic relapse occurred 6 years after transplantation. The survival rate of AML patients grafted during the first remission is 55% (16/29) with a median observation time of 41 months. For patients grafted in first or consecutive remission of acute lymphoblastic leukemia, the survival rate is 50% (7/14) with a maximal observation time of 34 months. The overall incidence of GvHD in patients at risk was 28% in aplastic anemia, 26% in AML, 9% in ALL, and 63% in CML. In aplastic anemia, no patient developed an interstitial pneumonia. In leukemia, the risk of fatal interstitial pneumonia was 34%.

Antineoplastic Combined Chemotherapy Protocols

Bone marrow transplantation in severe aplastic anemia and acute or chronic leukemia.

In Essen 121 bone marrow transplantations were carried out. The indications were severe aplastic anemia (n = 18), acute leukemia in relapse (n = 20), acute leukemia in remission (n = 46) or chronic myeloid leukemia (n = 37). The conditioning regimen consisted of cyclophosphamide or the combination of cyclophosphamide and total body irradiation. All patients were treated under strict gnotobiotic care. To mitigate the risk of CMV infections intravenous CMV-hyperimmunoglobulin and CMV-negative blood products have been applied routinely since two years. MTX was used as prophylaxis against GVH-disease. In case of severe aplastic anemia 13 patients (72%) are still alive with a median observation time of 24 months. In the prognostically unfavourable group of acute leukemia in relapse only one patient showed long term survival. In this patient leukemic relapse occurred six years after transplantation. The survival rate of AML patients grafted during the first remission is 55% (15/27) with a median observation time of 40 months. For patients grafted in first or consecutive remission of ALL the survival rate is 42% (5/12) with a maximal observation time of 29 months. Out of 37 patients grafted because of CML, eight were in an advanced stage of the disease. 13 patients are still alive, the maximal observation time is 37 months. The overall incidence of GVHD in patients at risk was 28% in aplastic anemia, 26% in AML, 9% in ALL and 63% in CML. In aplastic anemia no patient developed an interstitial pneumonia. In leukemia the risk of fatal interstitial pneumonia was 34%.

Acute Disease

Bone marrow transplantation for chronic granulocytic leukaemia.

Twenty-one patients with chronic granulocytic leukaemia underwent marrow transplantation. The donors were human-lymphocyte antigen-identical siblings in 19 cases. In the remaining 2 cases the donor was a parent in one and an identical twin in the other. The preparatory regimen included cyclophosphamide and 8.6 Gy total body irradiation given at either a dose of 0.1 Gy/min or 0.04 Gy/min. Five patients were in the accelerated phase of the disease, one was in remission following blast crisis, and the rest were all in the chronic phase. After chemotherapy and irradiation, all patients received bone marrow transplants. To date, nine patients are still alive, with a median survival of 64 days (range 28-683 days). One patient continued to have leukaemic cells and in another, the leukaemia recurred 18 months following transplantation. Interstitial pneumonitis was the cause of death of eight patients (38%). Graft-versus-host disease occurred in ten patients (47%).

Adolescent

[Gnotobiotic studies on SPF mice in relation to a study of tumor development in the colon after cholecystectomy].

The relation between cholecystectomy and colon carcinogenesis has not been fully elucidated. As bacteria may be involved in the carcinogenic process, we investigated the effect of cholecystectomy and dimethylhydrazine (DMH) administration to SPF NMRI mice with regard to tumour genesis and bacterial colonisation of the intestine. It results from this study that cholecystectomy does not influence tumour genesis and that 6-7 months post operationem and DMH administration tumours and bacteria originally not found in the animals develop: clostridia, eubacteria spec. which cannot be differentiated and E. lentum. Theses changes appear in group II of mice (laparotomy and DMH) and group III (cholecystectomy and DMH), but not in group I (controls). From the results of this study we cannot conclude whether the tumours or the new bacteria appeared first. Biochemical investigations of C. innocuum, C. paraputrificum and C. tertium indicated that these bacteria metabolised bile acids by a specific metabolic step only but not produced carcinogenic substances themselves. If bacteria are involved in tumorgenesis, different species may be involved producing a carcinogenic environment by metabolic chain reactions. We know of such a bacterial collaboration in anaerobic infections.

Animals

[Bacteriology and chemotherapy].

In a farewell lecture the relevance of bacteriology for the education of medical students is described. In the times of Koch and Pasteur the bacteriological diagnostic of epidemic diseases was the main problems, to day it is the isolation and differentiation of the patient's own bacteria which give the background for resistance or sensitivity tests to chemotherapeutics. The choice of antimicrobial substances depends not only on the sensitivity of the individual bacterial strain or the toxicology of certain substances but also on the necessity to preserve the normal microecology of the gut and other biotopes. This normal bacterial colonisation is an important factor of colonial resistance against superinfection. Other points for the choice of antimicrobial substances are the epidemiological distribution of resistant strains and the possible interference between the immunological system and certain antibiotics.

Anti-Bacterial Agents

Laminar air flow versus barrier nursing in marrow transplant recipients.

Forty-eight patients with acute leukaemia in relapse (n = 14), acute leukaemia in complete remission (n = 19), chronic myeloid leukaemia (n = 8) or severe aplastic anaemia (n = 7) received a marrow transplant. The first 26 patients were nursed in laminar-air-flow plastic isolators while the next 22 patients were treated in barrier nursing rooms. Gnotobiotic parameters and morbidity in the 2 groups are compared. Good decontamination of the gastro-intestinal tract was obtained using either of the 2 isolation techniques. The incidence of bacterial and mycotic infections, as well as the supportive care required by the patients was almost equal in both groups. Our results also suggest that the incidence of graft versus host disease may decrease with efficient decontamination of the patients.

Anemia, Aplastic

Excretion of azlocillin and mezlocillin by the normal pancreas and in acute pancreatitis in dogs and rats.

Dogs and rats were studied to evaluate the excretion of two new acyl-ureidopenicillins, azlocillin and mezlocillin, in the pancreatic fluid. After intravenous administration of 55 mg X kg-1 of either drug, an extremely low concentration (less than 3.0 micrograms X ml-1) of both antibiotics was measured in pancreatic juice of conscious dogs. In rats, both azlocillin and mezlocillin were excreted by the pancreas in bactericidal concentrations (greater than 10 micrograms X ml-1) during the first 15 min following their injection. In anesthetized dogs and rats in which acute pancreatitis was induced by injection of sodium taurocholate into the main pancreatic duct, the tissue concentration of mezlocillin (55 mg X kg-1 i.v.) was significantly higher than in the pancreatic tissue of control animals. In both instances, bactericidal concentrations of mezlocillin were measured in the pancreatic tissue. During the first 30 min following its injection, the concentration of mezlocillin was about five times higher in inflammed pancreatic tissue than in the normal pancreas (dogs: 44 +/- 14 vs. 5 +/- 3 micrograms X g-1 tissue; rats: 67 +/- 10 vs. 13 +/- 2 micrograms X g-1). These data indicate that (1) azlocillin and mezlocillin are excreted in bactericidal concentrations by the normal pancreas only in rats but not in dogs, and (2) in both species, bactericidal concentrations of mezlocillin can be observed in the normal pancreatic tissue and in acute pancreatitis; its concentration being significantly higher in acute pancreatitis than in controls.

Acute Disease

[Nalidixic acid: urinary levels during short-term therapy with reduced doses].

The acute inflammation of the lower afferent urinary tract is a superficial mucosal infection so long as structural and functional anomalies are excluded. A single or brief administration of antibacterially active substances with high urine concentrations can shorten uncomplicated attacks of infection and diminish the symptoms. The investigation of the urinary concentration of biologically active metabolites after administration of a daily dose of 2 g nalidixic acid revealed values which ensure that the minimum inhibitory concentrations in the afferent urinary tract are exceeded. The different responsiveness of the fluorimetric and microbiological methods applied for determination of the biologically active substances in urine led to results which were well correlated.

Adult

[Bone marrow transplantation for aplastic anaemia and acute leukaemia (author's transl)].

Twenty-six bone marrow transplantations were performed at the West Germany Tumour Centre at Essen between December 1975 and December 1981. Three patients had aplastic anaemia, 23 acute leukaemia. Of the leukaemia patients 13 had a recurrence and ten were in full remission at the time of the transplantation. Two of the patients with a recurrence received deep-frozen autologous marrow from the remission phase. One patient with aplastic anaemia had an identical twin as donour, while all other patients received allogeneic marrow from histocompatible family members. Eleven patients are still alive, all three of those with aplastic anaemia, one of those with leukaemia in a recurrence, and seven of those with acute leukaemia in full remission. Two of the survivors have a chronic graft-host reaction, but the others are symptom-free, after an observation period of up to four years. Main causes of death were leukemic recurrence (6), infection (5), and graft-host reaction (2). It would seem that at present bone marrow transplantation offers the best chance of a cure for severe aplastic anaemic and acute leukaemia in adults, but only if transplantation is undertaken early and not in the end-stage of the disease.

Acute Disease