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Biomedical subjects

R Ringelmann

Publications and source records attributed to R Ringelmann.

At least 19 recordsLinked to original sources
PubMed1998

Comparison of Roche Cobas Amplicor Mycobacterium tuberculosis assay with in-house PCR and culture for detection of M. tuberculosis.

The new Roche Cobas Amplicor Mycobacterium tuberculosis assay, which is a semiautomated version of the manually performed Roche Amplicor M. tuberculosis test, was compared to culture and an IS6110-based in-house PCR protocol. A total of 1,681 specimens from 833 patients, including specimen types other than sputum, were tested in parallel by both the in-house PCR and the Cobas Amplicor M. tuberculosis assay. After we resolved discrepant PCR results, the sensitivity, specificity, and positive and negative predictive values for the Cobas Amplicor M. tuberculosis assay were 66.33, 99.71, 94.36, and 97.66%, respectively. The corresponding values for the in-house PCR were 91.08, 99.85, 97.87, and 99.37%, respectively. For culture- and smear-positive specimens, the sensitivity of the Cobas Amplicor M. tuberculosis test was 96.42% (in-house PCR, 100%). If only smear-negative sputum specimens were considered, the Cobas Amplicor M. tuberculosis assay exhibited a sensitivity of 45.45% (in-house PCR, 63.63%) relative to that of culture. With a modified protocol for DNA extraction (washing of samples plus ultrasonication), both PCR methods performed better with gastric aspirates than with sputum samples (sensitivity of the Cobas Amplicor M. tuberculosis assay with smear-negative gastric aspirates, 70.00%; sensitivity of in-house PCR, 90.00%). With dithiothreitol being used for liquefaction of specimens in this study, the Cobas Amplicor M. tuberculosis assay exhibited an inhibition rate of 9.16%. In our view, the new Cobas Amplicor M. tuberculosis test (i) is well suited for typing of smear-positive specimens, (ii) may also be applied to gastric aspirates and other types of specimens if DNA extraction methods are modified appropriately, and (iii) exhibits a sensitivity with smear-negative sputum specimens which makes it recommendable that a minimum of three samples from the same patient be tested.

Bronchoalveolar Lavage Fluid↗
PubMed1998

Detection of Cryptosporidium parvum in human feces by PCR.

C. parvum has a high pathologic potential also for man, especially for immununosuppressed patients. The microscopic detection of cysts in feces is neither easy nor always reliable. During the recent years, considerable progress has been achieved in establishing PCR-based approaches for i) sensitive detection of C. parvum in a variety of specimen types [3, 9-16, 18, 21, 24, 25, 27, 29-32, 34], ii) identification of individual genotypes of C. parvum [2, 4-7, 17, 19, 20, 22, 23, 26, 28, 33] and iii) viability testing of C. parvum organisms [8, 9, 13, 29, 30]. The protocols published so far include nested PCR [3, 8, 18, 34], RT-PCR [13, 29], and use of the UNG carryover prevention system [10]. The aim of this work was to establish a PCR system for the detection of C. parvum oocysts in stool samples, applying the same specimen preparation procedure as applied for immunofluorescence. In addition, we combined the UNG carryover prevention system with the use of long, PCR-generated digoxigenin-labelled probes, thus achieving a sensitivity comparable to nested PCR und circumventing the contamination risks associated with nested PCR protocols. We developed a simplified sucrose-cushion-based protocol for preparation of clinical specimens (adopted from [1]), satisfying both the needs of immunofluorescence and PCR. When tested with stool samples spiked with C. parvum oocysts, the analytical sensitivity of PCR was 3,500 oocysts/ml stool (immunofluorescence: 3,000 oocysts/ml stool), demonstrating that both methods were equivalent with respect to analytical sensitivity. However, when PCR and immnunofluorescence were applied to clinical samples (n=5) with known positivity for C. parvum, only the specimen with the shortest duration of storage (5 weeks) could be correctly identified by PCR (clinical sensitivity: 20%). Our results demonstrate, that the PCR approach presented in this work is not suited for highly sensitive detection of C. parvum in faeces. This was mainly due to the fact that sucrose-gradient purified material was used, which relies on the presence of morphologically intact oocysts in the specimens. Desintegration of oocysts by excystation and/or storage may lower the parasite yield of the protocol drastically. As a consequence, a protocol extracting the entire DNA from faeces should be used for PCR for detection of C. parvum [34].

Animals↗
PubMed1989

[Yeasts: cause of infections of the respiratory tract?].

Poor data are given in literature on the rate and concentration of yeasts on mucous membranes of the respiratory tract. Our data show a rate of lower than 0.2% (only concentrations of 10(4)-10(5) detected). In contrast to this low colonization rate, a percentage of higher than 20% can be detected in patients on intensive care units. The aetiologic role of yeasts in pneumonia and bronchitis can be evaluated more easily, if candida is not only found in a single tracheal or bronchial secretion, but in follow-up specimens and if yeasts can be detected in blood culture, urine, or from other mucous membranes. Our own experience underlines the value of the new tests for candida antigens: a titer higher than 1:4 is a strong hint for fungaemia.

Bronchi↗
PubMed1988

[Bacteriologic and serologic diagnosis of enteral infections].

Infections of the gastrointestinal tract still are numerous, ranging on the second place after infections of the respiratory tract. Some of them show quite severe or prolonged course. In contrast to other infections, especially those of the urinary tract, laboratory diagnostic of enteritis is only scarcely ordered. During the last ten years new methods and knowledge of etiologic germs like Campylobacter, Yersinia, various types of E. coli, Clostridium difficile, Rotavirus, Adenovirus, Giardia, Blastomyces and Cryptosporidia have been accumulated. A better etiologic diagnosis of these infections should enable the clinician to start a more precise and therefore more effective therapy.

Antibodies, Bacterial↗
PubMed1988

[Hepatitis non-A, non-B-associated substance in stool from patients with posttransfusion and sporadic hepatitis].

A hepatitis non-A,non-B-associated substance (HNANB-AS) excreted in feces has been detected by means of a sandwich radioimmunoassay using reconvalescent serum and IgG from patients with posttransfusion HNANB. 4380 stool filtrates from 1599 patients were screened with this assay. In patients with posttransfusion or sporadic acute and chronic HNANB the substance was detected with a mean frequency of 34%, in acute posttransfusion HNANB, where samples were screened at the beginning of the clinical symptoms, 71.4% of stool specimens were positive for HNANB-AS. A high frequency of positive results was found in patients undergoing dialysis (31.3%), hemophiliacs (16.6%) and patients with cryptogenic cirrhosis (16%). Positive specimens were seen in hepatitis A (7.1%), acute and chronic HBV-infection (9.6%), various liver diseases (7.8%), outpatients of a physician (3.1%) and clinical or laboratory staff (6%). In these groups, too, anamnestic data speaking in favour for a possible HNANB frequently were obtained. The discovery of a partially double-stranded circular DNA of 5.0 Kb in HNANB-AS which sequence differs from human, bacterial and known viral DNA, argues the presence of a viral particle in stools of patients with sporadic and parenteral HNANB.

Acute Disease↗
PubMed1987

[Incidence of deep respiratory tract infections].

The distribution of respiratory tract infections (RTI) among the general population is not uniform. The incidence in neonates and the elderly (older than 65) is 2 to 3 times higher than that in adults. Examinations to determine the responsible pathogen are conducted in less than 1% of cases of RTI. The overall incidence of Haemophilus influenzae and Streptococcus pneumoniae in hospitalized patients amounts to 13 to 27%. The incidences of Staphylococcus aureus, Klebsiella and Pseudomonas aeruginosa in intensive care units are approximately 20% each. The management of the disease should be based on an aetiological diagnosis, and must take the individual patient's condition into account. Examination of the sputum or bronchial rinsing fluid is still the most reliable form of diagnosis, however, a sufficient number of quantitative methods must be applied. In hospitalized--and especially intensive care--patients these methods are often successful in isolating H. influenzae and pneumococci which we cannot afford to ignore as pathogens.

Bacterial Infections↗
PubMed1987

[Microbiologic-immunologic laboratory diagnosis in suspected meningitis/encephalitis].

The diagnosis on the exclusion of infectious diseases of the central nervous system, especially of bacterial infections still is one of the most important issues in clinical microbiology. In bacterial meningitis, where lethal courses as well as severe sequelae are still frequent, there should be a rapid diagnosis not only with microscopy but also with Limulus test and antigen detection tests because a specific therapy should be initiated as soon as possible. But also viral infections caused by varicella or herpes virus are increasingly susceptible to chemotherapy. The indication for the examination of cerebrospinal fluid, the minimal volume for exhaustive laboratory tests and the possibilities of a stepwise diagnostic procedure are given with reference data from literature for the various techniques. In our experience the synopsis of laboratory results and clinical symptoms yielded in 75% of all cases the exclusion of an infectious etiology of the disease. In 17% a bacterial meningitis or the infection of a hydrocephalus shunt could be diagnosed. Viral infections could be proven in 4% either by antibody or by antigen detection. Only in 1% of all patients the clinical symptoms and the laboratory parameters remained unclear.

Antigens, Bacterial↗
PubMed1986

[Causative spectrum of bacteremia and sepsis: significance for therapy].

Nowadays, infection with septicemia still can be a life-threatening disease. We evaluated the therapeutic behavior of clinicians basing on our diagnostic experiences during the last years and data from continuous epidemiological analysis. Important statements resulted on therapy without knowledge of the pathogen. Our results allow us to calculate the probabilities of various kinds of pathogens as well as their resistance patterns, dependent on the ward. One third of our isolates were staphylococci, followed by about 15% E. coli. The portions of all the other pathogens, e.g. other gram-negative rods, streptococci or anaerobs, were 2% or less. The application of various classes of antibiotics has been rather constant in the years 1981-1984, the penicillins showing a slight increase while the cephalosporins decreased. However, our data proved the cephalosporins to be of marked better efficacy. This points out the importance of such evaluations, whose results must be given to the physicians.

Anti-Bacterial Agents↗
PubMed1986

[Blood culture: efficacy of the specimens for the analysis of bacteremia and sepsis].

The indication for examination of blood cultures is discussed. The evaluation of clinical information with respect to the underlying diseases demonstrated that in most cases a microbiological etiology was suspected. Mostly we obtained diagnosis like chill, septic shock or suspicion of nosocomial infection. In most cases the infection origin was related to the gastrointestinal tract or the genitourinary tract. The examination of different specimens yielded the blood culture bottle as the best medium for diagnosis of septicemia. The laboratory diagnostic procedure is briefly presented. The rate of positive results, the contamination rate and the interpretation are discussed.

Blood Specimen Collection↗
PubMed1985

[Irritant effect of tensides on occupational dermatitis patients in hairdressing and nursing occupations. Comparative studies of healthy persons and neurodermatitis patients].

The irritational disposition of the skin was studied in a control group of 12 healthy persons, 8 patients with neurodermitis, 11 hairdressers with occupational dermatitis and 11 nurses with occupational dermatitis by using the Duhring-chamber-scarification test. For comparison, the alkali resistance test was also carried out. The results show that with the alkali resistance test the irritational disposition towards tensides may not be judged. The present findings show that the increased irritational disposition toward detergent substances seems to be a constitutional factor which favors the development of occupational dermatitis in hairdressing and nursing jobs; with the patient suffering from atopic dermatitis, one must presume an increased irritational disposition towards tensides in most cases.

Adult↗
PubMed1985

[Laboratory diagnosis in suspected infections of the urinary tract].

Rules for diagnostic procedure in patients with urinary tract infections are presented: the different indications for the investigation, the optimal specimen and the different laboratory methods. At this point the value of the determination of infection markers is investigated. Relating to our own experience we propose a stepwise diagnostic procedure. Different constellations of results for infection markers, quantitative bacteriological findings and the detection of antibacterial activity are discussed. Antibiotic therapy for uncomplicated urinary tract infections and for complicated cases are presented briefly.

Bacterial Infections↗
PubMed1984

[Listeriosis: case report and repetitorium].

Three cases of listeriosis are presented: The first patient was a 72-year-old man, who had an operative removal of a thymom one and a half year ago. In 1983 he developed polyradiculitis and was treated with cortison. Three months later he developed meningeal symptoms. In the cerebrospinal fluid 10(5) per ml Listeria monocytogenes could be isolated. Under treatment with chloramphenicol and gentamycin he was cured. The second case was a female 84-year-old patient, who suddenly developed drowsiness and meningism. In the cerebrospinal fluid Listeria in low concentration was isolated. In spite of therapy with penicillin G and gentamycin in high dosage the patient got centralnervous spasms and died on the second day. The third patient was a premature born infant (31. week of pregnancy) with shortness of breath and hydrocephalus, that was treated with ventriculo-peritoneal shunts on both sides. In her fourth month she got a shunt-defect; Listeria in low concentration was isolated out of the cerebrospinal fluid. Treated with gentamycin intrathecal and amoxycillin she was successfully cured. Epidemiology, pathogenesis and new knowledge about diagnosis and therapy of Listeria are presented.

Aged↗
PubMed1983

[Diagnosis and therapy of newborn infants of mothers with so-called "positive Wassermann"].

With modern immunological methods of syphilis diagnosis--TPHA, FTA-ABS., cardiolipin complement-fixation reaction, separation of specific IgM-antibodies, paired sample analysis--it is possible to distinguish between antibodies, which are stimulated by prenatal treponemal infection and those transmitted through the placenta. Investigation of maternal blood during pregnancy facilitates an early diagnosis and therapy as well as it saves an unnecessary prophylaxis of the newborn. If the investigation of the maternal blood has not been possible, it has to be done in the newborn blood, optimally in the cordblood. Fourteen cases during the last five years illustrate the possibilities and limitations of serodiagnosis. In three cases a recent syphilis infection during pregnancy was diagnosed, only in one of these newborns there was detectable an infection of the fetus. With regard to the remaining eleven cases a connatal infection could be excluded by calculating also the halftime of the treponemal antibodies of IgG and IgM class.

Antibodies, Bacterial↗