Pharyngeal Carriage and Antimicrobial Resistance of <i>Haemophilus influenzae</i> in Non-Type-b-Vaccinated Healthy Children Attending Day Care Centers in Turkey

Abstract

Background: The true prevalence of Haemophilus influenzae carriage rates in Turkey is unknown. As surveillance of pharyngeal carriage of resistant strains is important for initiating adequate empirical antimicrobial therapy, with the present study, we aimed to determine the carriage rates and antimicrobial resistance patterns of H. influenzae isolated from healthy children attending day care centers (DCCs) in Istanbul, Turkey. Methods: A total of 195 healthy children were included from two DCCs. Pharyngeal swabs were cultured for H. influenzae which were identified according to standard microbiologic procedures. Antimicrobial susceptibility tests were performed by the agar dilution method in accordance with the guidelines of the National Committee for Clinical Laboratory standards. β-Lactamase production was determined by the nitrocefin disc test. Results: The average pharyngeal carriage rate of H. influenzae was determined as 48.7%: 7.2% type b, 7.6% other capsulated strains, 33.9% noncapsulated strains, with a carriage peak between 0 and 11 months (68.1%). The ampicillin resistance observed in 7.3% of H. influenzae isolates was associated with a presence of β-lactamase, except for one isolate which was interpreted as β-lactamase-negative ampicillin-resistant strain. The resistance of H. influenzae to sulbactam/ampicillin, cefuroxime, azithromycin, tetracycline and cotrimoxazole was 0.5, 1.5, 0.5, 2.9 and 28.6%, respectively. Cefotaxime, ceftriaxone, ciprofloxacin and imipenem resistance was not detected. Conclusion: Our data show that the upper respiratory tract of about 48.7% of children was colonized with H. influenzae. This high colonization rate indicates that there is a need for surveillance of pharyngeal carriage of resistant strains in healthy Turkish children attending DCCs.

Leading infectious diseases problems in Turkey

“…The most problematic drug is trimethoprim–sulphamethoxazole, with one‐third of all isolates being non‐susceptible. Other antimicrobials, including β‐lactams, quinolones, macrolides, and tetracyclines, seem to be effective in >90% of H. influenzae isolates in Turkey (Table 1) [157–164]. Although ampicillin resistance appears to mainly correlate with β‐lactamase production, 0–2.8% (median, 1%) of all H. influenzae isolates were identified as β‐lactamase‐negative ampicillin‐resistant strains [158,159,161,163].…”

Rational antibiotic therapy and the position of ampicillin/sulbactam

“…AMS has comparable activity to AMP against bacteria that are resistant to ␤-lactam antibiotics as a result of mechanisms other than ␤-lactamase production [17], such as S. pneumoniae. Table 1 summarises recent AMS susceptibility data [19][20][21][22][23][24].…”

Staphylococcus aureus in Iowa child care facilities

“…reported that 2.3% of Hib isolated from Turkish child care attendees produced β-lactamase (Bakir 2002). In another study conducted in Turkish child care attendees, ampicillin resistance was observed in 7.3% of isolates, the majority of which were Hib (Torun 2007).…”

“…pneumoniae population made up of "epidemic" strains, as well as a more heterogeneous population that is unique to each facility ( (Marchisio 2001, Fontanals 2000, Oguzkaya-Artan 2007, Akcakaya 2001, Stratchounski 2001, Peerbooms 2002, Masuda 2002, Dabernat 2003, Henriques Normark 2003, Sulikowska 2004, Bricks 2004, Kontiokari 2005, Zemlickova 2006, Torun 2007, Farjo 2004, da Silva and Marin 2001 Karimi 2009, da Silva 2001and Marin 2001, Akcakaya 2001, Bricks 2004, Bakir 2002. There is evidence that H. influenzae carriage is higher in the spring months than winter or fall (Marchisio 2001, Dabernat 2003, Sulikowska 2004.…”

“…Prevalence of β-lactam-producing organisms ranges from 0 to 44.5% of isolates in any given study conducted in child care attendees (Masuda 2002, Stratchounski 2001, Zemlickova 2006, Henriques Normark 2003, Neto 2003, Sa-Leao 2008, Dabernat 2003. Reduced susceptibility to amoxicillin and ampicillin ranges between 4.6 and 10.1%, and 5.5 and 7.3% of isolates, respectively (Zemlickova 2006, Peerbooms 2002, Marchisio 2001, Bricks 2004, Sulikowska 2004, Torun 2007.…”