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Propionibacterium acnes belongs to the cutaneous flora of humans and is rarely considered a pathogen in human diseases. It is a frequent contaminant in blood cultures; however, in some patients it has been identified as the causative agent of life-threatening infections. Within the last years we have observed an abrupt increase in severe P. acnes infections which prompted us to study in detail the clinical and microbiological features, risk factors, and outcomes of these cases. In a retrospective review of microbiological records of 905 Propionibacterium isolates from a five-year period (1990-95), 70 were identified from 20 patients with clinical and microbiological evidence of a P. acnes infection. The clinical syndromes included endocarditis (7 patients), post-craniotomy infections (6 patients), arthritis and spondylodiscitis (4 patients), endophthalmitis (2 patients) and pansinusitis (1 patient). The predominant predisposing conditions were previous surgery preceding the infection from 2 weeks to 4 years and implantation of foreign bodies such as prosthetic heart valves, intraocular lenses and ventriculo-peritoneal shunts. Therapy consisted of intravenous antibiotics in all cases and surgical procedures to remove infected tissue in eighteen patients. The outcome was favorable in sixteen patients (80 percent) who had a complete recovery. These data confirm the pathogenic potential of P. acnes in late post-surgical infections, in particular after implantation of a foreign body, and suggest a combined therapeutic approach with intravenous antibiotics and surgical removal of the infected tissue.

Due to the wide spectrum of clinical manifestations of Lyme neuroborreliosis laboratory investigations are necessary to confirm the diagnosis. Serum and CSF antibodies against Borrelia burgdorferi (Bb) as well as mononuclear CSF pleocytosis are usually present in patients with suspected neuroborreliosis. In some cases, however, the results may be conflicting, causing difficulty for the clinician in making a therapeutic decision. We therefore analysed the value of clinical symptoms, the presence of intrathecal antibody production against Bb with a modified IFA and a capture ELISA test, and the presence of Bb in the CSF with PCR testing in eleven children with suspected neuroborreliosis. In six of eight children with probable neuroborreliosis we could demonstrate intrathecal antibody production against Bb. In only one of these cases could Bb be detected in the CSF with the PCR assay. In two children the clinical manifestations consisting of erythema chronicum migrans and facial palsy, the presence of mononuclear CSF pleocytosis, and the presence of Bb specific antibodies in serum supported the diagnosis of neuroborreliosis, despite the absence of intrathecal specific antibodies. Three additional children with possible neuroborreliosis based on the occurrence of nonspecific clinical symptoms along with high serum antibody titers to Bb were included in the study. Intrathecal antibodies against Bb could not be detected and the PCR result was negative; therefore the diagnosis of neuroborreliosis was not substantiated in these three patients. We conclude that in addition to clinical symptoms, serological evidence and CSF findings suggestive of neuroborreliosis, the demonstration of intrathecal specific antibody synthesis against Bb may be helpful in establishing a definitive diagnosis of neuroborreliosis. The absence of CSF antibodies, however, does not necessarily indicate a lack of CNS involvement, especially if the examination is performed early in the course of disease. PCR testing in CSF is not suitable for routine application in the diagnosis of Lyme neuroborreliosis.

Bartonella (Rochalimaea) henselae and/or B. quintana are the causative agents of a variety of infections such as trench fever, bacillary angiomatosis, septicemia, peliosis hepatis and endocarditis. Recently, B. henselae has been identified as a major cause of cat scratch disease. Diagnosis of such infections is based on clinical information, histopathology, culture and serology. However, none of these methods alone is sufficiently sensitive or specific. We have used the PCR to search for DNA specific for B. henselae/B. quintana in 33 clinical samples and in 6 controls. In comparison with clinical data and histopathology, PCR was extremely specific (100%) and reasonably sensitive (61%). Possible explanations for the limited sensitivity of PCR are discussed. We conclude that PCR provides a useful adjunct for the diagnosis of infections caused by B. henselae and B. quintana.

OBJECTIVE: The susceptibilities to penicillin, tetracycline, erythromycin, gentamicin, vancomycin and teicoplanin of 58 strains of Corynebacterium jeikeium were assessed by disk diffusion and agar dilution reference methods. METHODS: Zone sizes and minimal inhibitory concentrations (MIC) by agar dilution were interpreted using the ranges in the NCCLS tables for organisms other than Haemophilus, Neisseria gonorrhoeae, and Streptococcus pneumoniae. RESULTS: By agar dilution, 14%, 88%, 17% and 26% of the 58 isolates were susceptible to penicillin, tetracycline, erythromycin, and gentamicin, respectively. Using the breakpoints for Listeria monocytogenes, all strains showed concordant results for penicillin by disk diffusion. Discrepancies in the interpretative categories by disk diffusion were found in four cases (two very major and two minor) for tetracycline, in nine (two very major, two major, and five minor) for erythromycin, and in 1 case (very major) for gentamicin. All 58 strains were susceptible to vancomycin and teicoplanin by agar dilution and disk diffusion. The overall agreement of interpretative disk diffusion for all six antibiotics was 95.9%. In addition, all strains were susceptible to both glycopeptides by E-test. However, for vancomycin the MIC results in 58.6% were two log2 dilutions and in 1.7% more than two log2 dilutions higher by E-test than by agar dilution, whereas for teicoplanin agreement within one log2 dilution was 100%. CONCLUSIONS: Further evaluation of methodologies of disk diffusion is required to obtain a better agreement for erythromycin and tetracycline. The criteria of the NCCLS for interpretation of disk diffusion are adequate for susceptibility testing of C. jeikeium to penicillin, gentamicin, vancomycin and teicoplanin.

Diphtheria is an acute communicable disease of man caused by C. diphtheriae. Pharyngeal and cutaneous forms are described, where from both toxigenic and nontoxigenic strains can be isolated. The occurrence of C. diphtheriae in dairy cattle has already been reported in the past. The pathogens were isolated from ulcerated teats and from the milk of cows with mastitis as well. These animals were considered to play a role in the transmission of the disease to man. This paper describes the isolation and characterization of C. diphtheriae in a 4 years old cow with generalized, partly ulcerative and purulent skin lesions. Bacteriological examination revealed the presence of very numerous corynebacterium-like organisms, which were characterized as C. diphtheriae subsp. belfanti, a nontoxigenic subspecies of C. diphtheriae. The significance of C. diphtheriae in veterinary medicine and the possible role of cattle as a reservoir of these organisms are discussed.

Bartonella henselae, the major causative agent of cat scratch disease, was cocultivated with Vero cells on chamber slides and visualized by indirect immunofluorescence by using a patient serum containing specific antibodies. Confocal microscopy localized the granular B. henselae-specific fluorescence mainly around the nuclei of Vero cells. By transmission electron microscopy, these granules were identified as clusters of multiple intracellular organisms. Fixed slides with the monolayers of Vero cells with intracellular B. henselae were used for an indirect fluorescent-antibody test to investigate the seroprevalence of specific immunoglobulin G in 100 serum samples from blood donors. Seventy-four serum samples were negative; 19, 3, and 4 were positive at dilutions of 1:64, 1:128, and 1:256, respectively. In our population, a serum titer of 1:256 or greater should stimulate further investigations. Moreover, elucidation of the mechanism by which B. henselae enters the cells may help to understand the pathogenesis of cat scratch disease.

Three human isolates of Capnocytophaga canimorsus from blood cultures showed no growth when cultivated on sheep blood agar plates based on BBL Columbia agar base, whereas the same three strains grew excellently on sheep blood agar plates based on Difco Columbia agar bases No. 2 or EH. Two of the three strains also grew well on blood agar plates based on bioMérieux Columbia agar. Strains that grew better on either Difco or bioMérieux Columbia based blood agar plates were found among Eikenella corrodens, Haemophilus aphrophilus, Kingella kingae, Lactobacillus sp., and Streptococcus adjacens, but these strains were never lost when cultivated on BBL Columbia agar plates. One strain of Lactobacillus failed to grow on Difco Columbia No. 2 agar and showed best growth on bioMérieux Columbia agar. Strains of Corynebacterium G 2, Corynebacterium afermentans and Streptococcus adjacens showed poor growth on chocolate agar when compared to blood agar media. Microbiologists should be aware of the importance of media formulations for optimal recovery of fastidious organisms.

Neurologic complications are common in Lyme borreliosis. In adults in particular, detection of intrathecally formed antibodies to B. burgdorferi is a decisive diagnostic criterion. As in neurosyphilis diagnosis, the specific antibody titer against B. burgdorferi in the CSF is compared with the serum titer by calculating the specific antibody indices, taking into account the disturbed blood/CSF barrier. Deriving from these specific indices, we adapt by dilution the serum IgG level to that in the CSF of the same day, thus allowing for passive diffusion of antibody through the blood/CSF barrier. Determination of the specific antibody titer by indirect immunofluorescence demonstrates intrathecal synthesis of specific antibodies against B. burgdorferi if the CSF titer is higher than in the diluted serum tested in parallel. The individual methods are presented in a group of patients.

A case of laboratory-acquired infection with Escherichia coli O157:H7 is presented. Evidence of the identity of the infecting strain was provided by toxin type and plasmid profiles. Because no obvious technical errors in laboratory practices could be demonstrated we conclude that the infecting dose for E. coli O157:H7 may be small. The clinical course was uncomplicated; during reconvalescence, the patient's serum recognized a unique 87 kDa band on immunoblots of the infecting strain.

In a retrospective study, false negative readings of CMV Scan results were detected. In a following prospective survey of 72 transplant donor sera, CMV Scan had a sensitivity and a negative predictive value of greater than 95%. Although CMV Scan is a rapid and useful test, a higher reliability can be achieved if results are controlled by another sensitive test or, at the least, CMV Scan is read by two different persons.

The use of agarose gel electrophoresis for rotavirus detection is a suitable routine method if simplifying modifications are introduced. Incorporation of ethidium bromide into the agarose gel permits its use for several times in the course of one week without further staining of the RNA segments. The electrophoresis chamber with a UV-light-transparent bottom is put directly onto the transilluminator and the RNA bands of the rotavirus can be visualized without manipulating the gel tray. During the winter of 1990/91, we found a good sensitivity (98%) of this method in comparison to a latex agglutination test (Slidex Rota-Kit 2, bio Mérieux).

The aim of this study was to investigate the correlation between clinical diagnosis of exanthema subitum and seroconversion of herpes virus type 6 (HHV-6). 90 children with fever of unknown origin were investigated by 11 pediatricians in the Canton of Zürich, Switzerland, between October 1989 and June 1990. Antibodies against HHV-6 were determined at the first consultation and 2-3 weeks later. History and clinical findings were investigated and the clinical probability of the diagnosis exanthema subitum was estimated. 82 of the 90 children could be evaluated. 33 of them already had HHV-6 antibodies in their first blood sample although their history was negative concerning exanthema subitum. In 24 children exanthema subitum was proven by seroconversion. The clinical diagnosis was much more reliable at the second consultation compared to the first one. The clinical course of the disease was highly variable. Duration of fever differed widely and in some children the exanthema was atypical or even absent.

Fifteen out of 24 risk neonates from the premature baby ward (= 63%) and 36 of 79 healthy neonates from the infant nursery (= 46%) at a Zürich hospital were infected within a period of 29 days during a nosocomial epidemic human rotavirus (HRV) outbreak. Forty-two out of 51 of all HRV-infected babies (=82%) manifested clinical symptoms, but these could not all be attributed to an HRV infection. On average, rotavirus could be detected in infected risk neonates five days after their admission to the premature baby ward. Eleven of the 15 risk neonates were infected within 10 days after the admission of the index case. Immediately after detection of the epidemic process, specific detailed countermeasures were instituted, including hand protection and hand disinfection, individual nursing set and cohorting of already infected babies. Early institution of such measures and information of all persons responsible for treatment and care of the babies concerned are crucial for success.

The present study investigates the incidence of human rotavirus excretion in neonates of two hospitals. From April 1, 1983 to March 31, 1984, rotaviruses were detected with Rotazyme in the feces of 57 (15%) of 383 neonates at the Department of Pediatrics, University of Berne, in a total in 71 (5.2%) of the 1369 stool samples tested. Of the 57 neonates with Rotazyme-positive stool samples, 53 (93%) were asymptomatic. The problems of the specificity of Rotazyme in neonatal feces and the possibility of rapid testing on neonatology wards are discussed. In a prospective study carried out in April 1986 at the "Schweizerische Pflegerinnenschule in Zurich", rotaviruses were detected with genome gel electrophoresis in the feces of 15 (63%) of 24 risk neonates in the premature baby ward and in 36 (46%) of 79 neonates from the infant nursery, in a total in 63 (34%) of the 188 stool samples tested. In this rotavirus outbreak all rotaviruses detected showed the same band pattern, and therefore had an identical electrophorotype. Symptoms and hospital hygiene aspects of this outbreak will be dealt with in subsequent papers.

In the context of a prospective study for detection of rotavirus infections, an outbreak in neonates was observed in April 1986 at the Schweizerische Pflegerinnenschule in Zurich. Altogether, 103 neonates were investigated by means of genome gel electrophoresis for rotaviruses (HRV, human rotavirus) in the feces in the course of April 1986. Of these 103 neonates, 51 (49%) were HRV-positive and 52 (51%) were HRV-negative. Of the 51 HRV-positive neonates, 42 (82%) showed clinical symptoms, especially a typically altered pathological quality of the feces and an increased frequency of fecal passage. Vomiting and fever were observed less frequently. The pathological quality of the feces proved to be significantly correlated with the infection of rotaviruses in the neonate at risk. Besides this, reduced feeding behavior, circulatory signs and in one neonate a convulsive state of unclear etiology were also observed. This has only been rarely described up to now in rotavirus infections in neonates. This study confirms that rotavirus may cause frequently slight symptoms in neonates, but sometimes also symptoms of a clinically significant extent.

The effects of the potent arteriolar vasodilator carprazidil on serum lipoproteins and various clinical, biochemical and endocrine parameters were assessed in 15 men with mild to moderate essential hypertension. Following a carprazidil monotherapy (average dose 50 to 60 mg/d) of 8 weeks (N = 15) or 16 weeks (N = 12) duration, blood pressure was decreased significantly (P less than 0.01), while serum high-density lipoprotein cholesterol (+ 26% and + 24%, respectively; P less than 0.01) and the alpha-lipoprotein fraction (+ 26% and + 41%) were increased. Low- and very low-density lipoprotein cholesterol, triglycerides, as well as mean body weight, blood and plasma volume, heart rate, and plasma renin, aldosterone, norepinephrine, and epinephrine were not consistently altered. These results indicate that treatment of hypertensive men with carprazidil in modest dosage may have a favorable influence both on blood pressure and serum lipoproteins.