Levofloxacin and moxifloxacin resistant Haemophilus influenzae in a patient with common variable immunodeficiency (CVID): a case report

Fluoroquinolones are important in the treatment of respiratory infections and resistance to them amongst Haemophilus influenzae is rare. We report a case of persistent respiratory tract colonization with an H. influenzae strain resistant to ciprofloxacin, levofloxacin and moxifloxacin.Two sputum cultures obtained 4.5 months apart, from a patient with common variable immunodeficiency (CVID), yielded H. influenzae in colony counts exceeding 107 CFU/ml. Antibiotic susceptibility testing using disk diffusion and E-tests revealed both isolates to be resistant to ciprofloxacin, levofloxacin and moxifloxacin.Although quinolone resistant H. influenzae remains extremely rare, its emergence in Sri Lanka heralds microbiological and clinical challenges with important implications for the treatment of community acquired respiratory infection.</p