1/11. Recurrent bacteremia caused by a "Flexispira"-like organism in a patient with X-linked (Bruton's) agammaglobulinemia.helicobacter spp., except for helicobacter cinaedi, have only rarely been reported in cases of septicemia. A patient with X-linked (Bruton's) agammaglobulinemia was found to have persistent sepsis with a helicobacter-like organism despite multiple courses of antibiotics. His periods of sepsis were associated with leg swelling thought to be consistent with cellulitis. The organism was fastidious and required a microaerophilic environment containing H(2) for growth. Optimal growth was observed at 35 to 37 degrees C on sheep blood, CDC anaerobe, and Bordet-Gengou agars. Serial subcultures every 4 to 5 days were required to maintain viability. The organism was strongly urease positive and showed highest relatedness to helicobacter-like organisms with the vernacular name "Flexispira rappini" by 16S rRNA gene sequence analysis. Genomic DNA hybridization studies, however, found 24 to 37% relatedness to "F. rappini" and even less to other helicobacter spp. Although the organism phenotypically resembles "Flexispira" and helicobacter, it is thought to represent a new taxon. The patient's infection was eventually cleared with a prolonged (5-month) course of intravenous imipenem and gentamicin.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/11. polymerase chain reaction detection of bartonella henselae bacteraemia in an immunocompetent child with cat-scratch disease.A case of bartonella henselae bacteraemia is reported in an immunocompetent 8-year-old boy with cat-scratch disease. serology to B. henselae, diagnosed by polymerase chain reaction, was positive. DNA was extracted from peripheral whole blood and amplified with specific primers targeting the htrA gene of B. henselae. A non-isotopic hybridization assay with a species-specific oligonucleotide probe was used to detect the amplified product. CONCLUSION: The polymerase chain reaction can be used for the rapid laboratory diagnosis of bacteraemia in cat-scratch disease.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/11. Epstein-Barr virus-associated recurrent necrotic papulovesicles with repeated bacterial infections ending in sepsis and death: consideration of the relationship between Epstein-Barr virus infection and immune defect.The disease of Epstein-Barr virus (EBV) -associated recurrent necrotic papulovesicles is a distinct clinicopathologic entity different from classic hydroa vacciniforme (HV). A few patients have been reported as atypical HV with systemic involvement, development of lymphoma, and poor prognosis. We describe a patient with recurrent necrotic papulovesicles and multiple varioliform scars in both sun-exposed and covered areas. In contrast to cases of previously reported atypical HV, our patient suffered from repeated bacterial infections on various sites ending in sepsis and death, but without malignant transformation. EBV was detected in the lymphoid cells from the skin lesions by anti-latent membrane protein (LMP) antibody and in situ hybridization. We suggest that the repeated bacterial infections in this case raise the possibility of an association of EBV infection with increased susceptibility to bacterial infections.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/11. bacteremia caused by a novel species of sphingobacterium.A Gram-negative rod was isolated from the blood cultures of an 84-year-old man with foot cellulitis. The bacterium was first identified as sphingobacterium spiritivorum on the basis of standard assimilation tests. However, sequencing analysis of its 16S rRNA genes and whole genome hybridization studies with other related bacteria showed that this isolate belongs to a so far undescribed species of sphingobacterium, close to S. mizutae. This bacterium was susceptible to most of the antibiotics tested, including glycopeptides, but was resistant to aminoglycosides and polymyxins. Treatment with amoxicillin-clavulanate cured the infection.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/11. Molecular relatedness of staphylococcus epidermidis isolates obtained during a platelet transfusion-associated episode of sepsis.staphylococcus epidermidis was isolated from the blood of a 25-year-old pregnant woman following the administration of eight units of platelets. She had developed chills and a fever of 41.4 degrees C soon after the transfusions were completed. S. epidermidis was also obtained from all eight platelet units, as well as from the packed-erythrocyte unit associated with the first unit of platelets. The isolation of the same organism from these epidemiologically related sources provided us with the opportunity to phenotypically and genetically characterize the isolates. Several typing methods, including four molecular techniques, were used to increase our chances of finding any differences between the isolates under investigation. Phenotypic analyses demonstrated that S. epidermidis isolates from the patient, platelet units, and erythrocyte unit reacted in exactly the same manner in 15 biochemical tests, exhibited slime production, and had the same antibiotic susceptibility pattern. Genetic analyses, which included plasmid profiles, plasmid cross-hybridization, field inversion gel electrophoresis, and ribotyping, substantiated the relationships between the S. epidermidis isolates from the patient, platelet units, and erythrocyte unit. Eight S. epidermidis control strains unrelated to the case were found to differ significantly from the platelet-related strain.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/11. bacteremia caused by a novel Bordetella species, "B. hinzii".Bordetella spp. cause respiratory tract diseases in warm-blooded animals. Only bordetella bronchiseptica has been reported to cause bacteremia in humans, and this rare infection usually occurs with pneumonia in immunocompromised patients. We describe "Bordetella hinzii" bacteremia in an AIDS patient without a respiratory illness. Combining biochemical phenotyping with fatty acid analysis permitted preliminary identification of this previously undescribed pathogen; identity was confirmed by DNA-DNA hybridization. This report extends the spectrum of human infections caused by the bordetellae.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
7/11. Primary septicemia caused by vibrio cholerae non-o1 acquired on Cape Cod, massachusetts.We describe a patient with non-O1, non-O139 Vibrio cholerae septicemia associated with hemorrhagic bullous skin lesions of the lower extremities. The patient had underlying liver disease, and he probably acquired the organism through ingestion of raw clams. Although his condition rapidly improved during appropriate therapy, the patient's cellulitis and skin lesions persisted and he developed a fluid collection of the lower extremity that required drainage. Molecular methods were used to examine the non-O1 V. cholerae isolate for several known virulence factors of V. cholerae O1. The isolate failed to express cholera toxin and toxin-coregulated pilus (Tcp) and was negative in Southern hybridizations for ctxB, tcpA, toxR, and toxT. The vast majority of vibrio infections in the United States are clustered in the Gulf Coast area. This patient acquired the infection on Cape Cod. To our knowledge, this is the first case of non-O1 V. cholerae septicemia reported to have occurred in massachusetts. Given the high fatality rate of this infection, it is important for physicians to consider this diagnosis in patients who have underlying risk factors and appropriate epidemiologic exposures, even when they reside as far north as the new england states.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
8/11. bacteremia and chorioamnionitis due to cryptic genospecies of haemophilus influenzae biotype I.Nontypable strains of haemophilus influenzae are well-known causes of maternal and neonatal infections. Using DNA-DNA hybridization techniques, some of these strains have been shown to belong to a cryptic genospecies of Haemophilus, which is distantly related to haemophilus influenzae and Haemophilus hemolyticus. This report describes the first case of sepsis and chorioamnionitis due to haemophilus influenzae biotype I, which was identified using the RapIDNH system and then confirmed by multilocus enzyme electrophoresis to belong to this cryptic genospecies of Haemophilus. The electromorph type 92 of the isolate was consistent with that of biotype I of the cryptic genospecies.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
9/11. Characterization of two unusual clinically significant Francisella strains.We have isolated two phenotypically distinct nonfastidious Francisella strains (Fx1 and Fx2) from the blood of compromised patients with pneumonia and compared them with eight other Francisella strains, including francisella tularensis biovar tularensis, F. tularensis biovar novicida, and F. philomiragia. Our isolates grew well on sheep blood agar, chocolate agar, modified Thayer-Martin agar, and Trypticase soy agar. Fx1 and Fx2 were determined to be within the Francisella genus by cellular fatty acid analysis and by the utilization of glucose, production of H2S and catalase, and lack of motility, oxidase, nitrate reductase, and gelatinase. They were additionally shown to belong to the species F. tularensis by sequencing of two variable regions comprising approximately 500 nucleotides of the 16S rRNA gene. Also, rna probe hybridization confirmed their belonging to the species F. tularensis. However, the new strains, which are not identical, are distinguished from other F. tularensis strains by growth characteristics, repetitive extragenic palindromic PCR fragment pattern, and some biochemical tests. Key biochemical differences included the findings that Fx1 was positive for beta-galactosidase and arabinose hydrolysis and that both strains were citrulline ureidase positive and glycerol negative. Commercial F. tularensis antiserum agglutinated stock F. tularensis strains but not Fx1, Fx2, F. tularensis biovar novicida, or F. philomiragia; serum from either patient failed to agglutinate or only weakly agglutinated commercial antigen but showed agglutination when tested against each patient's respective isolate. Fx1 and Fx2 produced beta-lactamase. Because of their good growth, negative serology, and biochemical profile, the organisms could be misidentified in the clinical laboratory if standard strategies or commercial identification systems are used.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
10/11. Evolution of extended-spectrum beta-lactam resistance (SHV-8) in a strain of escherichia coli during multiple episodes of bacteremia.Nine isolates of escherichia coli were recovered from seven blood cultures over a period of 3 months from a 19-month-old female with aplastic anemia. Initial isolates were susceptible to extended-spectrum cephalosporins, including ceftazidime (MIC, < or = 0.25 microgram/ml), but gradually became resistant to this drug (MICs, > or = 128 micrograms/ml) and other cephalosporins and the monobactam aztreonam. molecular typing methods, including plasmid profile analysis, pulsed-field gel electrophoresis, and arbitrarily primed PCR, indicated that the nine isolates were derived from a common ancestor. Dot blot hybridization and PCR analysis of total bacterial DNA using blaSHV- and blaTEM-specific dna probes and primers identified the presence of a blaTEM beta-lactamase gene in all of the isolates and a blaSHV gene in the isolates with elevated ceftazidime MICs. isoelectric focusing analysis of crude lysates showed that all nine isolates contained an enzyme with a pI of 5.4 corresponding to the TEM-1 beta-lactamase, and those isolates containing an SHV-type beta-lactamase demonstrated an additional band with a pI of 7.6. The first of the ceftazidime-resistant isolates appeared to hyperproduce the SHV enzyme compared to the other resistant isolates. DNA sequencing revealed a blaSHV-1 gene in the first ceftazidime-resistant isolate and a novel blaSHV gene, blaSHV-8, with an Asp-to-Asn substitution at amino acid position 179 in the remaining four isolates. Three of the ceftazidime-resistant isolates also showed a change in porin profile. The patient had received multiple courses of antimicrobial agents during her illness, including multiple courses of ceftazidime. This collection of blood isolates from the same patient appears to represent the in vivo evolution of resistance under selective pressure of treatment with various cephalosporins.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
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