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ABSTRACT: Our previous study showed that (1)H-magnetic resonance spectroscopy ((1)H-MRS) can detect lipid peaks characteristic for Mycobacterium tuberculosis infection in cerebral lesions of young children; therefore, we aimed to extend and validate the application of (1)H-MRS for the diagnosis of active pulmonary tuberculosis lesions in three adolescent patients. Here, we document lipid peaks characteristic for M. tuberculosis infection by (1)H-MRS from lung tissue surrounding lung cavities of two patients whose sputum samples were positive for acid-fast bacilli by microscopy and positive for M. tuberculosis by genetic testing, indicating active tuberculosis. A similar lipid peak was found also in the pleural effusion of a third patient with concurrent lung cavity compatible with active tuberculosis. However, in a patient with a pyogenic pulmonary abscess, (1)H-MRS of the drained pus displayed different characteristic peaks but no lipid peak at all. CONCLUSION: Our findings further validate (1)H-MRS as a rapid, non-invasive, and specific diagnostic tool for active tuberculosis in children with microbiologically documented infection outside the central nervous system, specifically in the lungs.
European Journal of Pediatrics 07/2012; 171(8):1257-63. · 1.88 Impact Factor
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ABSTRACT: Toddlers are more prone to develop severe and extrapulmonary tuberculosis (TB) than older children. This is partially explained by differences in the immune response. Early and specific diagnosis is essential to start adequate treatment, especially if the central nervous system (CNS) is involved. The lack of sputum production and inherent dangers or impossibility of sampling CNS lesions may delay diagnosis. In addition, the magnetic resonance imaging (MRI) features of TB abscesses are non-specific and may mimic abscesses of other infectious etiology. (1)H-magnetic resonance spectroscopy ((1)H-MRS) may increase specificity of diagnosis by identifying lipids within the lesions that are considered characteristic for TB. Therefore, we studied four children with presumable CNS-TB with MRI and (1)H-MRS. In vivo and in vitro (1)H-MRS showed elevated lipid peaks within the TB lesions. CONCLUSION: (1)H-MRS allows to non-invasively identifying TB with high specificity and may allow early installment of targeted antimicrobial treatment.
European Journal of Pediatrics 02/2011; 170(3):379-87. · 1.88 Impact Factor
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Veasna Duong,
Trinh Thi Xuan Mai,
Kim Blasdell,
Le Viet Lo,
Claire Morvan,
Sreyrath Lay,
Wichittra Anukool,
Patimaporn Wongprompitak,
Yupin Suputtamongkol,
Denis Laurent, Beat Richner,
Chheang Ra,
Bui Trong Chien,
Roger Frutos,
Philippe Buchy
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ABSTRACT: Scrub typhus is an acute infectious disease caused by an obligate intracellular bacterium Orientia tsutsugamushi following the bite of infected trombiculid mites of the genus Leptotrombidium. This zoonotic disease is a major cause of febrile illness in the Asia-Pacific region, with a large spectrum of clinical manifestations from unapparent or mild disease to fatal disease. O. tsutsugamushi is characterized by a very high genomic plasticity and a large number of antigenic variants amongst strains. The 56-kDa type specific antigen (TSA) gene, encoding the major antigenic protein, was used as reference to investigate the genetic relationships between the strains and to genotype O. tsutsugamushi isolates. The open reading frame of the 56-kDa TSA gene of 41 sequences (28 Cambodian and 13 Vietnamese strains) from patient samples were sequenced and used for genotyping. The 28 Cambodian isolates clustered into 5 major groups, including Karp (43.5%), JG-v (25%), Kato/TA716 (21.5%), TA763 (3.5%) and Gilliam (3.5%). Karp (77%), TA763 (15.5%) and JG-v (7.5%) strains were identified amongst the 13 Vietnamese isolates. This is the first countrywide genotyping description in Cambodia and in Central Vietnam. These results demonstrate the considerable diversity of genotypes in co-circulation in both countries. The genotyping result might raise awareness amongst Cambodian and Vietnamese clinicians of the high genetic diversity of circulating O. tsutsugamushi strains and provides unique and beneficial data for serological and molecular diagnosis of scrub typhus infections as well as raw materials for future studies and vaccine development.
Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 01/2011; · 3.22 Impact Factor
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Philippe Buchy,
Sek Mardy,
Sirenda Vong,
Tetsuya Toyoda,
Jean-Thierry Aubin,
Megge Miller,
Sok Touch,
Ly Sovann,
Jean-Baptiste Dufourcq, Beat Richner,
Phan Van Tu,
Nguyen Thi Kim Tien,
Wilina Lim,
J S Malik Peiris,
Sylvie Van der Werf
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ABSTRACT: Between January 2005 and April 2006, six patients of influenza A/H5N1 virus infection were reported in Cambodia, all with fatal outcome.
We describe the virological findings of these six H5N1 patients in association with clinical and epidemiologic findings.
Broncho-alveolar lavage, nasopharyngeal, throat and rectal swabs and sera were cultured for virus isolation and viral load quantified in clinical specimens by real-time RT-PCR. We compared sequences obtained from different body sites within the same patient to detect viral quasi-species.
H5N1 virus strains isolated in Cambodia belong to genotype Z, clade 1 viruses. H5N1 viruses were isolated from serum and rectal swab specimens in two patients. The haemagglutinin gene sequences of the virus in different body sites did not differ. Amino acid substitutions known to be associated with a change in virus binding were not observed.
The high frequency of virus isolation from serum and faecal swabs highlights that H5N1 is likely to be a disseminated infection in humans and this has implications for antiviral treatment, biosafety in clinical laboratories and on risks for nosocomial and human-to-human transmission. There were no tissue-specific adaptive mutations in the HA gene from viruses isolated from different organs.
Journal of Clinical Virology 08/2007; 39(3):164-8. · 3.97 Impact Factor
