An article published in the journal The Lancet reports that using fluoroquinones to treat children with tuberculosis that is resistant to multiple drugs has led to the development of pneumococci in children that is also resistant to this class of drugs.
The conclusions of the study conducted by Dr Anne von Gottberg (National Institute for Communicable Diseases, Gauteng, South Africa) and colleagues came from an analysis of 21,521 cases of invasive pneumococcal disease, such as severe pneumonia and meningitis, between 2000 and 2006. The researchers screened 90% of the cases (19,404 isolates) for resistance to a fluoroquinone called ofloxacin. Patients were deemed levoflaxacin-resistant if they had minimum inhibitory concentrations (MIC) of 4 mg/L or more. MIC is lowest concentration of an antimicrobial that will inhibit the visible growth of a microorganism after overnight incubation. The authors assessed 65 children for carrying nose and throat pneumococcal in two tuberculosis hospitals that were known to have invasive pneumococcal disease caused by levofloxacin-resistant Streptococcus pneumoniae.
There were 12 cases of levofloxacin-resistant, invasive pneumococcal disease found in children, all of whom were less than 15 years old. Five of the patients died of the eleven whose outcomes were known. The researchers found an association between invasive pneumococcal disease caused by levofloxacin-resistant S pneumoniae and a history of TB treatment. That is, 89% of children (8 of 9) with non-susceptible isolates were treated for TB, and 18% of children (396 of 2202) with susceptible isolates were treated.
The researchers also found that among children hospitalized who carried nose and throat pneumococcal, almost all of these bacteria were resistant to levofloxacin.
“Our data suggest that the use of fluoroquinones to treat multidrug-resistant tuberculosis in children has led to the emergence of invasive pneumococcal diseases caused by levofloxacin-non-susceptible S pneumoniae and its nosocomial spread among children,” write the authors.
Emergence of levofloxacin-non-susceptible Streptococcus pneumoniae and treatment for multidrug-resistant tuberculosis in children in South Africa: a cohort observational surveillance study
Anne von Gottberg, Keith P Klugman, Cheryl Cohen, Nicole Wolter, Linda de Gouveia, Mignon du Plessis, Ruth Mpembe, Vanessa Quan, Andrew Whitelaw, Rena Hoffmann, Nelesh Govender, Susan Meiring, Anthony M Smith, Stephanie Schrag.
The Lancet (2008). 371[9618]:1108-1113.
doi:10.1016/S0140-6736(08)60350-5
Written by: Peter M Crosta