Serological biomarkers for monitoring response to treatment of pulmonary and extrapulmonary tuberculosis in children and adolescents.

Key measures to halt the spread of tuberculosis (TB) include early diagnosis, effective treatment, and monitoring disease management. We sought to evaluate the use of serum immunoglobulin levels against antigens present in cell envelope of Mycobacterium tuberculosis to monitor TB treatment response in children and adolescents with pulmonary (PTB) or extrapulmonary TB (EPTB). Blood samples were collected prior to and one, two, and six months following treatment initiation. Serum immunoglobulin levels against cardiolipin, sulfatide, mycolic acid and Mce1A protein were measured by ELISA. Serum from 53 TB patients and 12 healthy participants were analyzed. After six months of successful treatment, there was a significant decrease (p < 0.0001) in IgM levels against cardiolipin, sulfatide, mycolic acid and Mce1A protein and IgG levels against Mce1A protein when compared to baseline immunoglobulin levels. There was no significant variation in antibody levels during follow-up between participants with PTB and EPTB, confirmed and unconfirmed TB diagnosis, and HIV infection status. Antibody levels in control participants without TB did not decrease during follow-up. These results suggest that immunoglobulin responses to mycobacterial cell wall products may be a useful tool to monitor treatment response in children and adolescents with PTB or EPTB.

Living Conditions as a Driving Factor in Persistent Methicillin-resistant Staphylococcus aureus Colonization Among HIV-infected Youth.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) colonization has been linked to HIV-related sexual and social behaviors. MRSA risk factors may be different for HIV-infected children, adolescents and young adults. We investigated the association of MRSA colonization, persistent colonization and genotypes with potential risk factors among HIV-infected youth. METHODS: For this case-control study, patients 24 years of age or younger attending 2 HIV reference centers were recruited from February to August 2012 and followed for 1 year. Nasal swabs were collected at enrollment and every 3 months. MRSA clones were characterized by staphylococcal chromosomal cassette mec typing, spa typing and multilocus sequence typing. We compared MRSA colonization and persistent colonization with patient demographic and clinical characteristics. RESULTS: Among 117 participants, MRSA colonization frequency (calculated for each collection based on the number of positive cultures per patient) was 12.8% at the first collection. The average MRSA colonization frequency was 10.4%. Our results showed 11.1% were persistent carriers (subjects with more than 1 positive culture in at least 3). Crowding was the only factor associated with MRSA colonization (P = 0.018). Persistent carriers had significantly higher (4.2 times) odds of living in a crowded household (95% confidence interval-1.1-16.2). We observed high genetic diversity among MRSA isolates, with t002/ST5 and t318/ST30 being the most frequent. CONCLUSIONS: MRSA colonization among HIV-infected youth is more closely related to living in a low-income or slum community than to HIV-related clinical factors. High genetic MRSA isolate diversity in our population suggests frequent transmission.

Draft Genome Sequence of a Community-Associated Methicillin-Resistant Panton-Valentine Leukocidin-Positive Staphylococcus aureus Sequence Type 30 Isolate from a Pediatric Patient with a Lung Infection in Brazil.

The sequence of methicillin-resistant Staphylococcus aureus strain B6 (sequence type 30 [ST30], spa type t433, staphylococcal chromosomal cassette mec element [SCCmec] type IVc, Panton-Valentine leukocidin [PVL] positive), isolated from a pediatric patient with a lung infection in Niterói, Rio de Janeiro, Brazil, is described here. The draft genome sequence includes a 2.8-Mb chromosome, accompanied by a 20-kb plasmid containing blaZ and two small cryptic plasmids.