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M Seibold

Publications and source records attributed to M Seibold.

33 records · Page 2Linked to original sources
PubMed1989

Use of the membrane filtration technique and Staib agar for the detection of Cryptococcus neoformans in the urine of AIDS patients--a contribution to diagnosis, therapy and pathogenesis of cryptococcosis.

For the cultural control of Cryptococcus neoformans (Cr.n.), among the routinely examined standard specimens like CSF, sputum, blood, etc., urine earns special attention. The combination of membrane filtration technique (MFT) and Staib agar for the detection of Cr.n. from body fluids as described by Staib in 1963 was used for the cultural isolation of Cr.n. from urine of AIDS patients. In 3 examplary cases the diagnostic significance of this method could be demonstrated: The brown colour effect (BCE) of Cr.n. of a single CFU, as well as in colonies growing with a high density, was produced on average within 3-5 d/26 degrees C. The method was found to be useful for the evaluation of antimycotic therapy. One example of the survival of a few CFUs of Cr.n. under treatment with fluconazole as compared to the efficacy of therapy with amphotericin B + flucytosine, and one example of a re-emergence of Cr.n. in the urogenital tract after a too short duration of treatment with amphotericin B + flucytosine are shown. For the exclusion of the survival of single CFUs of Cr.n. in the urogenital tract of males, quantities up to 1 l of urine for the combination of MFT and Staib agar are proposed. As a secondary observation, it was found that this diagnostic combination in addition to its primary purpose, can serve to detect the metabolic end products of the human body present in urine which may influence capsule formation of Cr.n. neoformans.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Cryptococcus neoformans in the seminal fluid of an AIDS patient. A contribution to the clinical course of cryptococcosis.

In a 33-year-old HIV-positive homosexual male suffering from unexplained headache, cryptococcosis was diagnosed in a progressive secondary stage. After treatment with the standard combination therapy of amphotericin B + flucytosine for 34 d, the patient was clinically symptom-free and discharged, upon his own request, from the hospital. He remained under ambulatory mycological control. After an interval of 65 d during which the urine had been free from Cryptococcus neoformans (Cr.n.), the fungus could not be isolated from urine but 3 X 10(5) CFUs/ml were found in the seminal fluid. Andrologically, teratospermia and hyposemia were present. There were no clinical signs in the genitourinary tract including the prostate. The significance of ecological niches for Cr.n. colonization of the genitourinary tract after antimycotic therapy is discussed. In such cases, in addition to cultural examination of urine for Cr.n. by the membrane filtration technique (MFT) and Staib agar, an additional cultural examination of seminal fluid is recommended. It is also proposed to pay more attention to Cr.n. in andrological examinations. Special regard should be given to a possible occurrence of Cr.n. in the seminal fluid of AIDS patients. In cytology of the seminal fluid, use of the Giemsa stain is unsuitable for the purpose of Cr.n. detection. For this reason, it should be supplemented by PAS staining.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Staib agar supplemented with a triple antibiotic combination for the detection of Cryptococcus neoformans in clinical specimens.

It was demonstrated that the in vitro growth of a mucoid Escherichia coli strain from the urine of an AIDS patient could disturb the concurrent growth of Cryptococcus neoformans and the development of its brown colour effect (BCE) on Staib agar (syn. Guizotia abyssinica creatinine agar, bird seed agar, niger seed agar etc.) supplemented with penicillin + streptomycin. Owing to the supplementation with the triple antibiotic combination of penicillin + streptomycin + gentamicin and the resulting inhibition of E. coli growth, the formation of an intense BCE of the Cr. neoformans colonies after 3 d at 26 degrees C could be observed. On the same medium supplemented with this triple antibiotic combination 40 Cr. neoformans strains tested showed growth with an intense BCE after 3 d at 26 degrees C; but on Emmons' neutral Sabouraud's dextrose agar (NSDA) supplemented with the same triple antibiotic combination, inhibition of growth was found. For the examination of clinical specimens for Cr. neoformans contaminated with gram-negative rod-like bacteria, Staib agar supplemented with this triple antibiotic combination is proposed. Various antibiotic supplements to primary recovery media for fungi are discussed and ecological interrelations of bacteria and fungi are emphasized.

Acquired Immunodeficiency Syndrome↗
PubMed1987

The brown colour effect (BCE) of Cryptococcus neoformans in the diagnosis, control and epidemiology of C. neoformans infections in AIDS patients.

Cryptococcus neoformans was found as the causative agent of cryptococcosis in 7 (3.6%) out of 195 HIV-positive persons, most of them being hospitalized. These 7 persons included 6 homosexuals and 1 heroin addict. The examinations were performed at the Mycology Unit of the Robert Koch Institute in Berlin (West) between 1984 and 1986. The brown colour effect (BCE) of the C. neoformans colonies on Guizotia abyssinica creatinine agar (with 0.1% glucose) within 2-5 days at 26 degrees C facilitated the diagnosis of disseminated cryptococcosis. In all 7 cryptococcosis cases, the antigen of C. neoformans was detected in serum and CSF by the latex agglutination test. The initial titres ranged from 1:100,000 to 1:160 in the serum and from 1:1280 to 1:10 in the CSF. In comparison to the progressive stage of the infection with the involvement of the various organs and high antigen titres, the fungus may be detected at an early stage in the respiratory tract only where low antigen titres are observed. All the C. neoformans isolates were found to belong to the variety neoformans. Proposals for an effective control of cryptococcosis are made.

Acquired Immunodeficiency Syndrome↗
PubMed1986

[Disseminated cryptococcosis in 2 AIDS patients. A contribution to cryptococcosis diagnosis in AIDS].

In two AIDS patients (homosexual men) microscopical demonstration of Cryptococcus neoformans in samples obtained by puncture of the liver (n = 1) and additionally of the spleen (n = 1) led to the diagnosis of systemic cryptococcosis. Using the India ink method capsulated Cryptococcus neoformans cells could also be detected in cerebrospinal fluid (CSF) and urine. Concomitant culture of the fungus from tracheal secretion, CSF, urine and faeces confirmed the diagnosis of a disseminated infection; the identification and germ count of C. neoformans was achieved by means of the differential-selective medium Guizotia-abyssinica-creatinine agar. The C. neoformans antigen titres in serum and CSF corresponded to the stage of the mycosis as detected by microscopy and culture. After a six-week course of treatment with amphotericin B and flucytosine (Ancotil), the fungus could no longer be isolated from the materials examined in one patient. Mycological monitoring aiming at the detection of C. neoformans in the tracheal secretions by means of the mentioned differential-selective medium is therefore recommended as a prophylactic measure in AIDS patients and persons at risk.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Fungal infections following heart transplantation.

Following heart transplantation (HTx), patients often suffer from mycoses due to the necessary immunosuppressive treatment to prevent rejection episodes. Oropharyngeal Candida infections which mostly occur after HTx under high-dose immunosuppressive therapy can be avoided and treated successfully by prophylactic medication to be started immediately after transplantation, either by using azoles (e.g. fluconazole) or amphotericin B suspension. Contrary to this, invasive aspergillosis, beginning in the upper respiratory tract and the lung and mostly followed by hematogenous dissemination into various organs, is always a serious disease with high mortality. To avoid this infection, specimens from the respiratory tract, serum and urine should be examined mycologically prior to HTx. After HTx, apart from prophylactic avoidance of exposure to airborne fungal spores, close mycological control is mandatory to detect colonizations by aspergilli early. Timely administration of amphotericin B and 5-flucytosine, i.e. as soon as invasive growth is suspected, enables curative treatment of the often lethal course of this disease, even under immunosuppressive therapy.

Aspergillosis↗
PubMedDate not supplied

Susceptibility testing of Candida species for fluconazole: the role of buffering in the agar dilution assay.

The role of buffering in the determination of the minimal inhibitory concentration (MIC) of fluconazole was studied with Candida species. Agar dilution tests were performed on media (pH 7.25) buffered with either phosphate or morpholinopropane-sulfonic acid (MOPS) or endomethylene-tetrahydrophthalic acid (EMTA), 0.1 mol l-1 each, or on the unbuffered medium. It consisted of casitone and glucose supplemented with FeCl3 and MgSO4. The MICs recorded after 24 h at 37 degrees C extended from 0.1 mg l-1 to > or = 100 mg l-1 on the phosphate and EMTA medium, being concordant on both media. On the MOPS medium and the unbuffered medium the readings were also concordant; the MICs, however, were mostly 25 mg l-1 or higher. This increase of the values--up to six dilution steps--could not be correlated with the amount of acid secreted by the single strains. EMTA proved to be an alternative to phosphate in this system, and because it allows a faster growth of the yeasts it might be superior to phosphate. The concordance of the MIC values in the presence of such different buffer compounds tends to suggest that they indeed indicate the strongest inhibition attainable in vitro by fluconazole. MOPS was confirmed to be of no use in this system.

Candida↗
PubMedDate not supplied

Testing susceptibility of Candida species to fluconazole and itraconazole using the microdilution assay.

A microdilution system was established for testing the susceptibility of Candida species to fluconazole and itraconazole. The assay used a sodium phosphate-buffered (0.1 mol l-1) Casitone/glucose medium (pH 7.2) supplemented with potassium, iron, magnesium, trace elements and vitamins. Tests were read photometrically after 24 h, and the minimum inhibitory concentration (MIC) was defined as the IC90. In nearly all strains sharp end points were observed. The MICs against Candida species without any known pre-exposure to azoles were found to range from 0.2 to 1.56 micrograms ml-1 for fluconazole and from 2.3 to 12 ng ml-1 for intraconazole. For strains from candidosis patients refractory to treatment with fluconazole the MICs of fluconazole ranged from 6.25 to 100 micrograms ml-1, while those for itraconazole varied between 12 and > 450 ng ml-1. The strains did not respond congruent to both azoles. A similar disparity of the MICs was observed with Candida tropicalis and Candida krusei. The unusually low MICs of itraconazole were attained because (1) the dilution series was prepared from a preformed (concentrated) dilution series in 75% dimethylsulphoxide and not directly by serial dilution in the broth and (2) the incubation was performed in microtitre plates made of quartz glass rather than in the generally used polystyrene microtitre plates.

Antifungal Agents↗
PubMedDate not supplied

Cerebrospinal fluid indices in cryptococcal and tuberculous meningitis: the spider web coagulum and its diagnostic significance.

The differentiation between a chronic cryptococcal meningitis and a chronic tuberculous meningitis may cause problems for the clinician only if standard microbiological methods are not applied to the diagnosis of both infections. In a male non-AIDS patient (50 y), 11 years after a suggested diagnosis of "tuberculous meningitis", meningoencephalitis with hydrocephalus was diagnosed and treated accordingly without success. Mycobacterium tuberculosis was never found. Because fibrin fibres of a spider web coagulum in the CSF resembled Aspergillus mycelium, the patient was then treated with amphotericin B + flucytosine. Finally, a mycological examination led to the true diagnosis: (1) In the CSF, resembling Aspergillus hyphae were found to be spider web coagulum fibres. (2) Cryptococcal meningoencephalitis based on the detection of Cryptococcus neoformans in CSF and its antigen in serum and CSF. - At post-mortem, cryptococcal meningoencephalitis was established as cause of death. Residual signs of tuberculosis could not be detected in the brain and the meninges. Common clinical similarities of cryptococcal and tuberculous meningitis and the possibility of a double infection are discussed. A comparison of the presence of Cr. neoformans in the meninges of non-AIDS and AIDS patients is made. The formation of spider web coagulum in the CSF is discussed. Proposals for the diagnosis, therapy and prophylaxis of cryptococcal meningitis are made.

Cryptococcosis↗
PubMedDate not supplied

Persistence of Cryptococcus neoformans in seminal fluid and urine under itraconazole treatment. The urogenital tract (prostate) as a niche for Cryptococcus neoformans.

The open questions of the persistence of Cryptococcus neoformans in the urogenital tract under antimycotic treatment can be examined under optimal mycological-diagnostic conditions only. The example of a case of cryptococcosis in an AIDS patient diagnosed and treated with itraconazole in the early secondary stage of cryptococcosis is used to discuss the problems of the persistence of Cr. neoformans involvement in the urogenital tract (prostate). Data from a ten-week follow-up study are presented and discussed. The observations made have shown that itraconazole is effective in all regions of the body, with the exception of the urogenital tract. In addition to clinical examinations, cases treated with itraconazole should be finally subjected to cultural examination of prostatic secretion and/or seminal fluid, to exclude the possible presence of a symptom-free involvement of the prostate by Cr. neoformans.

Acquired Immunodeficiency Syndrome↗