PubMed Health⌕ Search

Biomedical subjects

K Janitschke

Publications and source records attributed to K Janitschke.

At least 37 records · Page 2Linked to original sources

Value of PCR for evaluating occurrence of parasitemia in immunocompromised patients with cerebral and extracerebral toxoplasmosis.

PCR was used to evaluate the occurrence of Toxoplasma gondii parasitemia by detection of the B1 gene in blood samples in two groups of immunosuppressed patients (148 subjects) suspected of having cerebral or extracerebral infection, respectively. Group I consisted of 52 patients with AIDS with suspected cerebral toxoplasmosis. The diagnosis was clinically proven in 15 cases. Parasitemia was detected by PCR in only two of these patients (13.3%), both showing evidence of disseminated infection. Group II consisted of 96 immunocompromised patients, either with AIDS or receiving iatrogenic immunosuppressive therapy. Of these patients, 65 (34 with AIDS and 31 others) showed abnormalities only in chest radiography and were first screened for the presence of Toxoplasma DNA in bronchoalveolar lavage fluid. Blood was then analyzed when the parasite was detected in the bronchoalveolar lavage fluid. The remaining 31 subjects (22 with AIDS and 9 others) were suspected of having extracerebral, pulmonary, or disseminated toxoplasmosis, and blood was studied directly in these cases. Among the nine patients with clinically diagnosed extracerebral infection in group II, the parasite was detected by PCR in the blood of five patients (55.5%), all having pulmonary toxoplasmosis. If all patients with clinical manifestations of extracerebral toxoplasmosis (from both groups) who had not received antitoxoplasma therapy when the samples were collected are considered, PCR detected parasitemia in seven of the nine cases (77.8%). The present study indicates that examination of blood by PCR may be valuable in cases of extracerebral toxoplasmosis because of the disseminated nature of the disease. Since most cases of cerebral toxoplasmosis result from the local reactivation of latent brain cysts, detection of parasitemia by PCR is useful only in cases associated with severe cerebral infection or dissemination of this disease.

Acquired Immunodeficiency Syndrome↗

Extracerebral toxoplasmosis in AIDS. Histological and immunohistological findings based on 80 autopsy cases.

Despite the great amount of literature concerning toxoplasmic encephalitis in AIDS patients, little is known about extracerebral toxoplasmosis. Therefore we conducted a study of 80 autopsy cases to estimate the frequency of extracerebral toxoplasmosis. A control group of 50 cases was completely negative for all markers applied. In 35 of the 80 AIDS-cases (43.7%), organisms could be detected. In 13 cases (16.2%) there was an extracerebral toxoplasmosis; 4 cases (5%) showed only extracerebral involvement and in 9 cases (11.2%), extracerebral toxoplasmosis occurred in combination with cerebral manifestations. In 22 cases (27.5%), only cerebral toxoplasmosis was found. The following organs were involved: cardiac muscle (15%), lungs (6.2%), liver (5%), pancreas (5%), gastrointestinal tract (6.2%), adrenal glands (5%), lymph nodes (5%) and testis (3.7%). In individual cases further organs, not mentioned above, were involved. Pseudocysts could be demonstrated within necroses and inflammatory foci by conventional staining, whereas trophozoites became apparent only immunohistologically.

Acquired Immunodeficiency Syndrome↗

Application of the polymerase chain reaction in the diagnosis of pulmonary toxoplasmosis in immunocompromised patients.

Bronchoalveolar lavage (BAL) fluid from 47 immunocompromised patients (26 with AIDS and 21 patients on immunosuppressive therapy) was analysed for the presence of Toxoplasma gondii DNA by means of the polymerase chain reaction (PCR). Specific target DNA derived from the B1 and P30 gene of Toxoplasma gondii was detected in BAL fluids from three patients with AIDS (6.4%). Pneumonia as the presenting feature of disseminated toxoplasmosis was confirmed by both clinical findings and by detection of Toxoplasma gondii DNA in blood obtained from two patients. The findings indicate that PCR has potential value in the detection of Toxoplasma gondii as an etiologic agent of atypical pneumonia in immunocompromised patients.

Animals↗

Improved sensitivity of the polymerase chain reaction for detection of Toxoplasma gondii in biological and human clinical specimens.

The aim of the present study was to improve the sensitivity of the polymerase chain reaction for detection of Toxoplasma gondii in biological and clinical specimens. Using a pair of primers amplifying a 634 bp fragment of the B1 gene of this parasite, it was possible to detect ten parasites in 100 microliters of sample suspensions containing a high concentration of concomitant host cells. A comparison of different DNA purification methods indicated that cell-rich clinical specimens intended for use as samples for the polymerase chain reaction should be digested with proteinase K prior to DNA amplification. By using the described sample preparation methods and the polymerase chain reaction, Toxoplasma gondii DNA was demonstrated in ten of 52 clinical specimens of patients with clinical or serological indications of toxoplasmosis.

Animals↗

Intestinal microsporidiosis in a German patient with AIDS.

Since intestinal microsporidiosis might be of importance in the pathogenesis of gastrointestinal symptoms in patients infected with HIV, we examined duodenal biopsies of HIV-infected patients by electron microscopy. Enterocytozoon bieneusi infection of the small intestine was found in one of 23 patients studied, which gives a 95% confidence interval for the prevalence rate between 0.1% and 22%. The infected patient was a 24-year-old homosexual male with AIDS who underwent upper endoscopy because of acute epigastric pain, nausea, and vomiting. These symptoms were obviously due to mesenterial Kaposi's sarcoma obstructing the duodenal passage, as was later revealed at autopsy. However, microsporidiosis might have caused the patient's eight-month history of diarrhea and weight loss, since infected cells showed signs of degeneration, and no other pathogens were ever detected in stool or biopsy. Our finding of Enterocytozoon bieneusi infection in a German AIDS patient supports the concept of a worldwide distribution of this parasite; further studies are needed to define its exact prevalence in HIV-infected patients and its pathogenic relevance.

Acquired Immunodeficiency Syndrome↗

Visceral leishmaniasis mimicking a flare of systemic lupus erythematosus.

Fever in systemic lupus erythematosus (SLE) may be caused by exacerbation of the disease itself or by infection. We report on a patient with a long standing history of SLE that was complicated by fever and pancytopenia with no splenomegaly. SLE disease activity was suspected because of an elevated DNA-antibody titer. The early positive response to corticoid therapy may have masked the underlying infection. Visceral leishmaniasis was diagnosed by a repeated bone marrow biopsy and serological testing.

Animals↗

Detection of antibody formation in mice, rats and rabbits immunized with different Pneumocystis carinii antigens.

Antibody formation to P. carinii of human origin was determined by an indirect immunofluorescence antibody assay (IFA) after immunization of mice, rats and rabbits with pronase-treated whole cysts and soluble antigen in order to obtain more detailed data about the production of polyclonal antibodies. Antibody titre profiles over defined periods have shown that noticeable differences between the immunoreactions to whole cysts and soluble antigen occur. The soluble antigen produced an earlier and stronger titre rise (peak titres of up to 1:2560 2 to 4 weeks after immunization). In contrast to this, whole cysts produced equally high, although retarded, antibody titre peaks only in normal mice and rats and when the dose had been doubled. Nu/nu mice failed to demonstrate any reaction to these P. carinii immunogens. Cross-reactivity of the antibodies with P. carinii antigen from rat lungs was demonstrated. Possible reasons for different immunoreactions to these antigens, the importance of proteolytic digestion for the results obtained and the potential applicability of these polyclonal antibodies to a histochemical demonstration of the parasite are discussed.

Animals↗

[Immunohistochemical demonstration of extracerebral toxoplasmosis in AIDS].

Tissue slides obtained at autopsy from 80 cases with AIDS were studied immunhistochemically for infection with Toxoplasma gondii. In 35 cases (43.75%) toxoplasmosis could be found: in 22 cases (27.5%) only cerebral, in 9 cases (11.25%) cerebral and extracerebral and in 4 cases (5%) only extracerebral. Necrotizing lesions, due to the parasite could be seen in brain, heart, lungs, pancreas, adrenal glands and testis, only intracellular trophozoites without tissue damage in GIT, liver, lymphnodes, spleen, prostate, kidney and gl. parotis. The trophozoites and pseudocysts could be clearly demonstrated by immunohistochemistry.

Acquired Immunodeficiency Syndrome↗

Malaria prophylaxis in travellers to tropical Africa.

This study investigated travellers to tropical Africa with regard to prophylactic treatment of malaria. A total of 5703 travellers completed a questionnaire on their flights back to the Federal Republic of Germany; 4116 passengers (73.7%) had visited East Africa, while 808 (14.5%) had been to West Africa. The results indicate that 90.2% took a regular chemoprophylaxis against malaria. Nevertheless, 8.1% of the travellers used no antimalarials and in 9.3% chemoprophylaxis was inadequate due to inappropriate advice; for example, 7.5% still took pyrimethamine-sulfadoxine as prophylactic. Mefloquine was correctly taken by 38.9% of the travellers in East Africa; 12.6% used it in West Africa where it is not necessary. Antimosquito measures have a high priority for travellers to tropical Africa and dissemination of this fact must be improved since only 72.6% followed through on such advice.

Africa↗

Prevalence and clinical importance of Entamoeba histolytica in two high-risk groups: travelers returning from the tropics and male homosexuals.

This study was undertaken to learn the prevalence of amebiasis and to assess the clinical importance of Entamoeba histolytica in two high-risk groups: 2700 travelers returning from the tropics and 320 male homosexuals. Some 16.3% of the homosexual men and 4.0% of the travelers had E. histolytica infections. Only five travelers showed a pathogenic zymodeme of E. histolytica, which correlated closely with invasive amebiasis with positive amebic serology and clinical symptoms with diarrhea. The homosexual group had neither a pathogenic isoenzyme pattern nor positive amebic serology. Currently, travelers to the tropics have a risk of 0.3% (1:340) of acquiring invasive amebiasis; 92.5% of all E. histolytica infections in travelers remain asymptomatic and are confirmed by serology and zymodeme status. No homosexual presented with invasive amebiasis.

Adult↗

Prevalence and control of Schistosoma haematobium infections in the Amran subprovince of the Yemen Arab Republic.

803 schoolchildren in the subprovince of Amran were examined for S. haematobium. The prevalence was 28.9%. Stool samples of 92 children were negative for S. mansoni eggs. Bulinus snails were most frequent, whereas Biomphalaria were rare. Control measures included chemotherapy and mollusciciding. The prevalence in 8 selected villages could be reduced by this from 36.3% down to 5.1%. No gross haematuria and only one single case of heavy infection were detected. Eradication of this disease seems feasible.

Adolescent↗

[The importance of Entamoeba histolytica in persons returning from the tropics].

Stools from 1000 travellers returning from the tropics were examined for intestinal parasites. The most frequently isolated intestinal pathogens were Giardia lamblia (5%) and E. histolytica (3.6%). For 21 out of 36 E. histolytica isolates iso-enzyme differentiation by starch-gel electrophoresis was possible, yielding a pathogenic pattern in four. This finding correlated closely with clinical symptoms and positive serology, while E. histolytica with non-pathogenic zymodeme should not be considered as a cause of diarrhoea.

Adult↗

Amebic liver abscess in a European patient: zymodeme classification of Entamoeba histolytica.

This is a case report of a 36-year-old patient who developed an amebic liver abscess after a stay in the Sudan. He was first misdiagnosed as having pneumonia of the right lower lobe. Following establishment of the correct diagnosis, the patient recovered fully after metronidazole treatment. The fecal culture in Robinson's medium yielded extensive growth of Entamoeba histolytica. Electrophoretic characterization proved it to be a zymodeme XIX, which is one of the zymodemes associated with pathogenicity in the host. This first report of a zymodeme classification of E. histolytica in Germany should initiate further epidemiological studies.

Adult↗

[Direct agglutination as a tool for toxoplasma control in pregnancy].

Sera of 3243 pregnant women were tested by direct agglutination and dye test for toxoplasma antibodies. An agreement of 99.48% between results of both tests could be found. The direct agglutination can be recommended as a screening technique in pregnancy care.

Agglutination Tests↗

Immunity to Acanthamoeba culbertsoni: experimental studies with Acanthamoeba and control antigen preparations.

Mice were intranasally immunized with living and killed Acanthamoeba as well as culture supernatant, living Toxoplasma and BCG, and challenged with pathogenic A. culbertsoni strain A-1. The best protection was achieved with killed amoebae of the same strain. A high rate of mortality was observed in immunized mice treated with immunosuppressives and challenged with A. culbertsoni A-1. The significance of the results in relation to environmental human infection is discussed.

Acanthamoeba↗