Immune restoration disease in HIV patient.

We describe a severely immunosuppressed HIV-1-positive man in whom immune restoration disease associated with pulmonary infection caused by Mycobacterium microti developed after antiretroviral treatment. The diagnosis was made by using convenient spoligotyping techniques, but invasive investigations were required to exclude a tumor.

High prevalence of the plasmid-mediated quinolone resistance determinant qnrA in multidrug-resistant Enterobacteriaceae from blood cultures in Liverpool, UK.

OBJECTIVES: To determine the prevalence of the plasmid-mediated quinolone resistance qnrA gene in a selected collection of blood culture isolates of Enterobacteriaceae resistant to both ciprofloxacin and cefotaxime. METHODS: Over a 29 month period, a total of 47 non-repetitive isolates of Enterobacteriaceae resistant to both ciprofloxacin and cefotaxime were identified. Isolates were screened for the presence of the qnrA gene, class I integrons and bla(ESBL) by PCR. Transferability was examined by conjugation with the sodium azide-resistant Escherichia coli J53. All qnrA-positive isolates were examined for DNA-relatedness by PFGE. RESULTS: A total of 15 of the 47 test isolates (32%) were positive for the qnrA gene, and included single isolates of E. coli and Citrobacter freundii, 4 Klebsiella pneumoniae and 9 Enterobacter cloacae. All 15 qnrA-positive isolates carried class 1 integrons, and 11 the extended-spectrum beta-lactamase gene bla(SHV-12). By PFGE two K. pneumoniae and three E. cloacae, respectively, were considered clonally but not temporally related. Plasmid transfer of quinolone resistance was only achieved with single isolates of K. pneumoniae and E. cloacae. Both plasmids carried class 1 integrons with a pSAL-1-like gene cassette arrangement intl1-aadA2-qacEDelta-sul1. CONCLUSIONS: In this selected group of ciprofloxacin- and cefotaxime-resistant bacteria, carriage of the qnrA gene was high (32%). This compares with <2.0% as demonstrated in worldwide studies of laboratory collections of ciprofloxacin-resistant bacteria. The majority of qnrA-positive isolates in our study originated from high-dependency care units within our hospital, but were shown not to be clonal by PFGE. This is the first report of qnrA-positive Enterobacteriaceae in the United Kingdom.

Detection of elements of the staphylococcal cassette chromosome (SCC) in a methicillin-susceptible (mecA gene negative) homologue of a fucidin-resistant MRSA.

OBJECTIVES: To determine the DNA relatedness of an outbreak of community-acquired fucidin-resistant methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) isolated from intravenous drug users (IVDUs). MATERIALS AND METHODS: Relatedness was determined by PFGE analysis of macro-restricted chromosome, together with a variety of PCR methods, to determine polymorphisms in the accessory gene regulator (agr) locus, the structure of the staphylococcal cassette chromosome (SCCmec) and the presence or absence of the gene encoding Panton-Valentine leucocidin (PVL). RESULTS: Clonality of the MRSA and MSSA was established by PFGE, a finding further supported by agr analysis. By PCR, the MRSA contained the typical genetic organization of SCCmec type-1. However, the MSSA, though mecA-negative, contained certain fragments of the SCC. Genes encoding PVL were not detected. CONCLUSIONS: This outbreak involved a community-acquired fucidin-resistant MRSA and its methicillin-susceptible homologue. The MSSA did not contain the mecA gene but did contain elements of the mobile type-I SCC. The MSSA were associated with a change in PFGE pattern with a deletion in fragment size of approximately 215-195 kb.