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B Henriques

Publications and source records attributed to B Henriques.

14 recordsLinked to original sources

RAPD-PCR and PFGE as tools in the investigation of an outbreak of beta-haemolytic Streptococcus group A in a Swedish hospital.

We evaluated the random amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) techniques for studying an outbreak of beta-haemolytic streptococci group A (GAS) occurred at two maternity wards at Danderyd hospital, Stockholm, Sweden. All the isolates were of T-type 8,25. The RAPD technique revealed that all RAPD-PCR profiles were identical. PFGE showed that all the patterns but one were identical. These patterns were compared with 10 different T-type GAS from the strain collection of the Swedish Institute for Infectious Disease Control (SMI) and T-type 8,25 from different years and locations. The SMI strains exhibited patterns different from each other and all different from the isolates from Danderyd hospital. Moreover, RAPD could not differentiate among the T-type 8,25 isolates from different years and locations but PFGE showed differences among the amplicons. Our results indicated that the RAPD and PFGE techniques could be efficient tools in epidemiological studies of GAS.

Cross Infection↗

Prospective study of prognostic factors in community-acquired bacteremic pneumococcal disease in 5 countries.

To define the influence of prognostic factors in patients with community-acquired pneumococcal bacteremia, a 2-year prospective study was performed in 5 centers in Canada, the United States, the United Kingdom, Spain, and Sweden. By multivariate analysis, the independent predictors of death among the 460 patients were age >65 years (odds ratio [OR], 2.2), living in a nursing home (OR, 2.8), presence of chronic pulmonary disease (OR, 2.5), high acute physiology score (OR for scores 9-14, 7.6; for scores 15-17, 22; and for scores >17, 41), and need for mechanical ventilation (OR, 4.4). Of patients with meningitis, 26% died. Of patients with pneumonia without meningitis, 19% of those with >/=2 lobes and 7% of those with only 1 lobe involved (P=.0016) died. The case-fatality rate differed significantly among the centers: 20% in the United States and Spain, 13% in the United Kingdom, 8% in Sweden, and 6% in Canada. Differences of disease severity and of frequencies and impact of underlying chronic conditions were factors of probable importance for different outcomes.

Aged↗

Molecular epidemiology of Streptococcus pneumoniae causing invasive disease in 5 countries.

A multicenter study was done during 1993-1995 to investigate prospectively the influence of several prognostic factors for predicting the risk of death among patients with pneumococcal bacteremia. Five centers located in Canada, the United Kingdom, Spain, Sweden, and the United States participated. Clinical parameters were correlated to antibiotic susceptibility and serotyping of the 354 invasive pneumococcal isolates collected and to molecular typing of 173 isolates belonging to the 5 most common serotypes (14, 9V, 23F, 3, and 7F). Serotype 14 was the most common among all isolates, but serotype 3 dominated in fatal cases and in isolates from Spain and the United States, the countries with the highest case-fatality rates. Fewer different patterns were found among the type 3 isolates, which suggests a closer clonal relationship than that among isolates belonging to other serotypes. Of type 3 isolates from fatal cases, 1 clone predominated. Other penicillin-susceptible invasive clones were also shown to spread in and between countries.

Adult↗

Invasive group A streptococcal infections in Sweden in 1994 and 1995: epidemiology and clinical spectrum.

A nationwide study of invasive group A streptococcal (GAS) infections in Sweden during 1994-1995 was carried out. All Swedish microbiological laboratories were asked to report isolates of GAS from normally sterile sites. During the study period they were also asked to send their isolates for T typing. Questionnaires were sent to the physicians in charge of each patient. The incidence, serotype, clinical presentation, symptoms and outcome were recorded. Clinical data were obtained for 468 of 556 patients with GAS bacteraemia. The lethality rate was 16%, but was much higher (37%) in the 113 patients who developed streptococcal toxic shock syndrome (STSS). Streptococci of serotype T1 dominated during the study period and were linked to the increase in invasive GAS infections. They also carried an increased risk of causing STSS. Invasive streptococcal disease with STSS most often has an unknown primary focus or is associated with soft tissue infections. Invasive streptococcal disease not associated with STSS most often has a skin infection as portal of entry or else an unknown focus.

Adolescent↗

Epidemiology of pneumococcal infections in Swedish children.

OBJECTIVE: This paper provides an overview of pneumococcal infections in Swedish children. METHOD: Data supplied by the Swedish Institute for Infectious Disease Control (SMI) provided information on invasive pneumococcal isolates and on isolates with reduced susceptibility to penicillin. Disease burden was estimated from data collected in northern Stockholm and Malmöhus County. RESULTS: Only 3-6% of the total number of invasive pneumococcal isolates came from children 0-15 years of age. Predominant serotypes in descending frequency were 7, 6, 14, and 23. Strains from all sources with reduced sensitivity to penicillin (MIC > or = 0.5 mg/l) were found in 3% of children and varied between 0.2% and 11%, with the highest value found in Southern Sweden (predominating strains were 9, 19, 15, 6, and 23). A 10-year review of all cases of meningitis in Northern Stockholm reflected an incidence of 10/100,000 (0-2 years) or 5.8/100,000 (0-5 years), with severe sequelae occurring in 20% of children. This information can be used to predict an annual incidence of 30 cases of meningitis in Sweden. CONCLUSION: The large proportion of serotype 7 among invasive isolates is distressing since this serotype is not represented in the present 7- and 9-valent protein-conjugated vaccines under development. However, the heptavalent vaccine, including serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F would (at a serotype level) provide coverage against 83% of the resistant isolates in Southern Sweden.

Adolescent↗

Emergence of vancomycin tolerance in Streptococcus pneumoniae.

Streptococcus pneumoniae, the pneumococcus, is the most common cause of sepsis and meningitis. Multiple-antibiotic-resistant strains are widespread, and vancomycin is the antibiotic of last resort. Emergence of vancomycin resistance in this community-acquired bacterium would be catastrophic. Antibiotic tolerance, the ability of bacteria to survive but not grow in the presence of antibiotics, is a precursor phenotype to resistance. Here we show that loss of function of the VncS histidine kinase of a two-component sensor-regulator system in S. pneumoniae produced tolerance to vancomycin and other classes of antibiotic. Bacterial two-component systems monitor environmental parameters through a sensor histidine-kinase/phosphatase, which phosphorylates/dephosphorylates a response regulator that in turn mediates changes in gene expression. These results indicate that signal transduction is critical for the bactericidal activity of antibiotics. Experimental meningitis caused by the vncS mutant failed to respond to vancomycin. Clinical isolates tolerant to vancomycin were identified and DNA sequencing revealed nucleotide alterations in vncS. We conclude that broad antibiotic tolerance of S. pneumoniae has emerged in the community by a molecular mechanism that eliminates sensitivity to the current cornerstone of therapy, vancomycin.

Animals↗

Septic cutaneous lesions caused by Mycobacterium malmoense in a patient with hairy cell leukemia.

Patients with hairy cell leukemia seem to be prone to infections with mycobacteria. This report describes a patient with hairy cell leukemia and pulmonary infection as well as disseminated cutaneous infection caused by Mycobacterium malmoense cultured from sputum and skin scrapings on Loewenstein-Jensen medium in eight weeks. Despite multiresistance of the causative strain, the infection was successfully treated with ethambutol, cycloserine and isoniazid.

Humans↗

Infection with Mycobacterium malmoense in Sweden: report of 221 cases.

Mycobacterium malmoense was first described in 1977 and today is second only to the Mycobacterium avium complex as a cause of atypical mycobacterial infection in Sweden. We retrospectively studied the records of 221 patients from whom M. malmoense was isolated during 1968-1989. M. malmoense was recovered from the respiratory tract of 171 patients (170 adults and one child) and from cervical lymph nodes of 36 patients (35 children and one adult). In addition, the organism was isolated from the urine of six patients, one of whom had disseminated disease and two of whom had abscesses caused by M. malmoense. A majority of the patients with pulmonary infection as well as the patient with disseminated disease had other underlying diseases.

Adult↗

Disseminated Mycobacterium malmoense infection in a patient with chronic granulocytic leukaemia.

Mycobacterium malmoense is an atypical mycobacterium previously isolated from lymph nodes in children and from adults with pulmonary disease. Disseminated infection is extremely rare and bone marrow involvement has never previously been described. We report a patient with chronic granulocytic leukaemia and persistent fever with granuloma in the bone marrow due to disseminated M. malmoense infection. The patient initially received treatment with isoniazid, ethambutol and rifampicin with clearance of mycobacteria in the bone marrow and clinical improvement. Sensitivity in vitro was established for streptomycin, amikacin, ethambutol and rifabutin. The patient eventually expired as a result of progressive respiratory failure from other opportunistic infections. At autopsy staining of samples from lung parenchyma revealed fungal hyphi but staining for Pneumocystis carinii and myobacteria were negative.

Adult↗

Mycobacterium malmoense: an easily missed pathogen.

The BACTEC system (Becton Dickinson, Sparks, Md.) was compared with culture on Löwenstein-Jensen egg medium for the detection of Mycobacterium malmoense in lymph node samples from children with lymphadenitis. It was found to be significantly more sensitive and rapid. The use of the BACTEC system is thus recommended as a complement to culture on solid media for the primary isolation of atypical mycobacteria, such as M. malmoense.

Bacteriological Techniques↗

Cellular internalisation of Clostridium difficile toxin A.

The cytopathogenic effect of toxin A from Clostridium difficile was studied in cultured human lung fibroblasts. The final effect was dependent on toxin concentration and exposure time. Binding of the toxin to cells occurred at 0 degrees C as well as at 37 degrees C. The latency before appearance of the cytopathogenic effect was dose-dependent with a minimum of 45 min. The appearance of a cytopathogenic effect in toxin-treated cells was prevented by the addition of trypsin, antitoxin, lysosomotropic agents, inhibitors of the energy metabolism, 200 mM KCl, 20 mM benzyl alcohol and by incubation at 18 degrees C. Several inhibitors of lysosomal proteases did not prevent the appearance of the cytopathogenic effect. When the extracellular pH was lowered to 4.5 for 5 min immediately after toxin binding the period of latency was significantly shortened. Likewise, the protective effects of lysosomotropic agents were abolished by lowering the extracellular pH. Chinese hamster ovary cell mutants, defective in acidification of their endosomes, were less sensitive to toxin A than wildtype cells. The results indicate that cellular internalisation of toxin A is necessary for intoxication. Moreover, we postulate that the toxin needs some sort of enzymatic activation which can take place only after exposure of the toxin to a low pH.

Animals↗

Cancer. A prospective study of patients' opinion and reaction to information about cancer diagnosis.

When asked before admission to hospital 74% of 640 surgical patients suffering from various abdominal diseases stated that they wanted to be told if examinations revealed they were suffering from cancer. A prospective study of 58 patients confirmed this wish and no regrets were noted 3 days and 3 months later. The immediate reactions to information were moderate and almost all patients adjusted well to the situation after a short, varying, initial phase with anxiety. No severe, untoward reactions were seen. In contrast to the traditional attitude in surgical wards this study suggests that generally cancer patients should be given the diagnosis.

Adaptation, Psychological↗

Combination of fibromuscular hyperplasia, renal aplasia, hypoplasia or dysplasia and otosclerosis occurring in the same individual or the same family.

We have found 3 reports of fibromuscular hyperplasia (FMH) of the renal arteries with hypertension occurring in 2 siblings as well as a few instances of renal agenesis and unilateral renal aplasia occurring in the same family. In this paper we report on FMH of the renal arteries in 2 women, one giving birth to a child with renal agenesis, the other to a child with a focally dysplastic hypoplasia of the kidneys. A third family is reported, heavily loaded with hypertension and otosclerosis, in which 2 siblings with FMH and otosclerosis were found. Another 4 patients without known heredity for hypertension, but with FMH combined with renal or urinary tract anomalies, are also reported. The findings are discussed, particularly in relation to the findings in a large material of chronic non-obstructive pyelonephritis, where in those with well maintained renal function, hypertension below the age of 40 was found predominantly in females with a positive family history of hypertension and signs highly suggestive of infected hypoplasia or dysplasia of the kidney.

Abnormalities, Multiple↗