How laminin-1 can be recognized by the protozoan parasite Tritrichomonas foetus: possible role played by the extracellular matrix glycoprotein in both cytoadhesion and cytotoxicity exerted by the parasite.

The isoform 1 of the extracellular matrix glycoprotein Laminin is known to be an important ligand for some parasitic protozoa including Trichomonas vaginalis. The bovine parasite Tritrichomonas foetus seems to display a similar recognition process to laminin-1, as some amino acid sequences found in the LNS module of laminin-1 can also be recognized by this parasite. Which of the laminin-1 residing adhesion sequences are recognized by T. foetus, and the role played by such a protein-cell recognition process in both cytoadhesion and cytotoxicity exerted by the parasite are the subjects briefly reviewed and discussed here.

Ultrastructural characterization of Anaerobiospirillum succiniciproducens and its differentiation from Campylobacter species.

The anaerobic spiral-shaped bacterium Anaerobiospirillum succiniciproducens was isolated from the blood of an AIDS patient for the first time in Europe. Electron-microscopical methods, especially negative staining, allowed rapid morphological classification and differentiation from Campylobacter species. While A. succiniciproducens revealed lophotriche flagellation all the investigated Campylobacter species showed monotriche flagellation. The cell diameter of A. succiniciproducens was at least double that of the investigated Campylobacter species. Other ultrastructural features, such as a ring-like structure underneath the flagellar area and fibrils arranged parallel along the axis, were also specific to A. succiniciproducens.

Seroprevalence of Lyme borreliosis in forestry workers from Brandenburg, Germany.

In 1992 blood samples were taken from 630 forestry workers in the state of Brandenburg, Germany, and an inquiry about tick bites and possible symptoms of Lyme borreliosis carried out in order to determine the seroprevalence of the disease. To estimate the rate of seroconversion within six months, 406 of the individuals were investigated a second time. IgG and IgM antibodies against Borrelia burgdorferi were detected in serum using an indirect immunofluorescence assay (IFA) and an immunoblot assay (IBA). Fifty-three percent of the forestry workers reported suffering a tick bite, 8% of whom recalled an erythema after the bite. Positive results were found more frequently in the forestry workers than in a control group of 200 healthy blood donors in both the IgG-IFA (8% vs. 4%, p < 0.05) and the IgG-IBA (18% vs. 5%, p < 0.05). The detection of IgG antibodies correlated with a tick bite and erythema history. There was a tendency of lower seropositivity by the IgG-IBA in individuals who treated the ticks before removal with chemicals or other agents compared to those without such treatment (16.8% vs. 23.9%, 0.05 > p < 0.1). Likewise, there was a tendency of lower seropositivity by the IgG-IFA in individuals being treated with antibiotics for other reasons compared to untreated individuals (3.15% vs. 8.9%, p < 0.05), although the two groups did not differ in the IgG-IBA (13.8% vs. 18.5%, p > 0.1). The rate of seroconversion within six months ranged from 5 to 7%. It is concluded that forestry workers in Brandenburg, Germany, are at risk for infection with Borrelia burgdorferi, but clinical signs of infection are rare.

Port-a-cath-related Fusarium oxysporum infection in an HIV-infected patient: treatment with liposomal amphotericin B.

The first case of Port-a-cath-related disseminated fusariosis in an HIV-infected patient is presented. Antifungal treatment with liposomal amphotericin B (AmBisome) in a dose of 2 mg kg-1 day-1 for 14 days was successful.

[Genomic DNA fingerprints of Legionella pneumophila serogroup 2 strains as an epidemiologic marker]. / Genomische DNS-Fingerprints von Legionella-pneumophila-Serogruppe-2- Stämmen als epidemiologischer Marker.

Using pulsed-field gel electrophoresis, DNA fingerprints of eleven Legionella pneumophila isolates of serogroup 2 were generated. It was shown that two strains from a patient suffering from pneumonia as well as three environmental strains isolated from the shower in the hotel where the patient stayed 5 days before his illness were identical. Six strains of the same serogroup isolated from other sources were clearly separated. Thus, DNA fingerprints by pulsed-field gel electrophoresis are excellent epidemiological markers for the rarely occurring serogroup 2 of Legionella pneumophila.

Six cases of travel-associated Legionnaires' disease in Ischia involving four countries.

The detection of travel-associated legionellosis can be extremely difficult; hence, an extensive case investigation is recommended in pneumonia-striken travellers and tourists, who are particularly at risk of acquiring the disease. On the Island of Ischia (Isola d'Ischia, Naples, Italy) a total of six cases of Legionnaires' disease occurred from 1986 to 1990. All patients (one man and two women from Germany, one Austrian woman, one Swiss man, and one Italian woman) had taken thermal baths and stayed in local hotels; they all experienced severe pneumonia, and three of them died. These cases were associated with hotels, and the hot-water supply was presumed to have transmitted the infection. Remedial procedures were applied to the hot-water plumbing of the hotels according to the WHO recommendations and were proved to be effective. The occurrences described in this paper stress the importance of rapid and accurate reporting of diagnosed cases to the country where the infection was probably acquired, in order to ensure early detection of endemic foci and emerging clusters of legionellosis.

Prevalence and diagnosis of Legionella pneumonia: a 3-year prospective study with emphasis on application of urinary antigen detection.

During a 3-year period the frequency of legionellosis in hospitalized patients with community-acquired and nosocomial pneumonias was 3.4% (23/684 cases) and 5.9% (33/559), respectively. Of the diagnostic tests evaluated, detection of Legionella pneumophila serogroup 1 antigen in urine had the highest sensitivity, with 86% of culture-proven cases being positive. Sensitivities of serologic tests and examination of respiratory secretions (culture and direct immunofluorescence) were 36% and 26%, respectively. The diagnostic value of serology and of examination of respiratory secretions can be low when specimens are obtained and processed under the typical conditions of hospitalization. Urinary antigen detection represents an important diagnostic addition, and examination of postmortem lung tissue from fatal cases with pneumonia is an important adjunct for estimating the prevalence of legionellosis and for assessing the effectiveness of premortem diagnostic tests.

Legionellosis in heart transplant recipients.

We report on 20 cases of Legionnaires' Disease (LD) in heart transplant recipients during a two-year study. The overall frequency in this setting amounts thus to 17% (20/115). In contrast, the frequency of legionellosis in postoperative cardiac patients without immunosuppression was only 4.7% (4/84). Legionellosis was diagnosed by culture and/or antibody detection in ten (20) as well as by the detection of urinary antigens in all 20 patients. Only nine (20) patients developed pneumonia, whereas five patients presented with nodular infiltrates. The remaining six patients had moderate fever with no signs of lung infection. In contrast to the majority of patients with other underlying diseases, antigen shedding lasted for long periods in most transplant patients. In high risk patients the application of conventional diagnostic methods together with regular urinary antigen testings (i.e. twice a week) may be advantageous for the early diagnosis of Legionella infection.

[Legionella pneumonia: pulmonary and extrapulmonary findings]. / Legionella-Pneumonie: Pulmonale und extrapulmonale Befunde.

Pulmonary and extrapulmonary findings in legionelloses generally do not permit any aetiological conclusions. The extrapulmonary phenomena are epiphenomena that can possibly be traced to the effect of a toxin.

Incidence and clinical features of community-acquired legionellosis in hospitalized patients.

In a two-year prospective study of patients hospitalized because of community-acquired pneumonia, the incidence of legionellosis was found to be 3.8% (17/442 cases). After S. pneumoniae, M. pneumoniae and influenzae viruses, legionellae were the fourth most frequently identified pneumonia agents. We evaluated the clinical data from 41 cases with legionellosis, 17 diagnosed in this prospective study and 24 prior to the study. The age range of all patients (22 women, 19 men) was 24-78 yrs (median 61.3 yrs), 14 of 41 cases (34.1%) had extrapulmonary organ involvement. Twelve patients (29.3%) died. The fatality rate was 4.5% (1/22 cases) in patients treated with erythromycin, and 57.9% (11/19 cases) in patients treated with other antibiotics. Antibiotics effective in legionellosis should be added to the routine therapy of community-acquired pneumonia when this aetiology can not be excluded.

The incidence of legionella pneumonia: a 1-year prospective study in a large community hospital.

In a 1-year prospective study, 28 of 476 pneumonia patients (5.9%) were diagnosed as having legionella pneumonia. Legionella pneumonia was diagnosed in 12 (5%) of 240 community-acquired pneumonias and in 16 (6.8%) of 236 nosocomial pneumonias. Four methods of establishing diagnosis were used: serum antibody detection, direct proof of legionellae by immunofluorescence, culture, and legionella antigen detection in urine. The latter method proved to be clearly advantageous to all other methods in establishing the diagnosis. Twelve of the 28 patients (42.8%) died; all of them had severe underlying diseases. The fatality rate in patients treated with erythromycin was 18.8% (3/16 cases) and 75% (9/12 cases) in patients treated with antibiotics other than erythromycin. In 57.1% (16/28 patients) legionella pneumonia was acquired nosocomially. The results of our study underscore the need to use a broad spectrum of legionella diagnostic methods routinely and to administer antibiotics effective against legionellae in cases of pneumonia of unknown cause.

Nosocomial legionella pneumonia: demonstration of potable water as the source of infection.

From January 1983 until December 1985, 35 cases of sporadic nosocomial legionella pneumonia, all caused by Legionella pneumophila, were diagnosed in a university hospital. L. pneumophila serogroup (SG) 1 was cultured from 12 of the 35 cases and compared to corresponding L. pneumophila SG 1 isolates from water outlets in the patients' immediate environment by subtyping with monoclonal antibodies. The corresponding environmental isolates were identical to 9 out of 12 (75%) of those from the cases. However, even in the remaining three cases identical subtypes were found distributed throughout the hospital water supply. From the hospital water supply four different subtypes of L. pneumophila SG 1 were isolated, three of which were implicated in legionella pneumonia. Of 453 water samples taken during the study 298 (65.8%) were positive for legionellae. Species of Legionella other than L. pneumophila have not been isolated. This may explain the exclusiveness of L. pneumophila as the legionella pneumonia-causing agent. Our results suggest that the water supply system was the source of infection.

Simultaneous infections with different serogroups of Legionella pneumophila investigated by routine methods and Fourier transform infrared spectroscopy.

Simultaneous infections with different Legionella spp. have rarely been described in the literature. We now report on seven sporadic cases of legionellosis of which three were simultaneous infections caused by multiple Legionella pneumophila serogroups. Four different legionellae were involved. L. pneumophila serogroup 1, two different types of L. pneumophila serogroup 4, and L. pneumophila serogroup 10 have been identified simultaneously from a lung tissue specimen of one patient. Specimens from two other patients each revealed two different legionellae of serogroups 1 and 4. The existence of different L. pneumophila serogroups in simultaneous infections has not only been documented by identifying the incriminated Legionella spp. by classical methods. In addition, preliminary results of Legionella spp. identification with the novel physical procedure of Fourier transform infrared spectroscopy have been presented to evaluate its possible applicability for routine diagnostic procedures.

Fatal legionellosis in patients with malignant hematologic diseases.

Pneumonia was present in 70/157 (44.6%) autopsied patients with malignant hematologic diseases. In 16/70 patients (22.9%), legionellae were found to be the causative agents by screening lung tissue specimens with the direct fluorescent antibody method. In 5/16 patients with Legionella pneumonia, in whom legionellosis had been suspected clinically, the diagnosis had already been established by serology, urinary Legionella antigen detection, and culture. These results provide evidence that legionellosis is an important pneumonia etiology in patients with malignant hematological diseases. Thus, Legionella diagnostics should be applied routinely, and antibiotics effective in the treatment of legionellosis should be added to the usual therapy in patients with etiologically unexplained pneumonias. In view of the common occurrence of relapses of Legionella pneumonia, antibiotic therapy should be continued for an extended period.

Demonstration of Legionella antigen in the urine: significance for differential diagnosis.

The most effective techniques presently in use for the early diagnosis of Legionnaires' disease are RIA- and ELISA-tests detecting Legionella antigen in urine specimens. We are reporting on our experience with the RIA for the detection of L. pneumophila serogroup 1-antigen in the urine of 30 patients with suspected legionellosis.