The Journal of Applied Research • Vol. 5, No. 3, 2005 473 Characteristics of Pathogens Recovered from the Tonsils and Adenoids in a Group of Lebanese Children Undergoing Tonsillectomy and Adenoidectomy Usamah Hadi, MD * Michel El-Hajj, MD * Marwan Uwaydah, MD† Nabil Fuleihan, MD * Ghassan M. Matar, PhD† *Department of Otolaryngology-Head & Neck Surgery, Faculty of Medicine,American University of Beirut, Beirut, Lebanon †Department of Microbiology and Immunology, Faculty of Medicine,American University of Beirut, Beirut, Lebanon grave consequences because of difficul- ty in breathing. In addition, recurrent infections, especially when there is involvement of the middle ear cleft, can lead to systemic sequelae. Tonsillectomy is considered to be the most common major surgical procedure of the pedi- atric population. 1 Resistant bacteria that can cause recurrent infections in the adenoids and tonsils have been an increasing concern over the past decade because of the widespread and prolonged use of antibi- otics. 2 It also is evident that the micro- biology of adenotonsillitis may vary with geographic location. 3 Several authors have investigated the microbial flora of the tonsils and adenoids individually, but only a few studies have compared the core flora of the tonsil and adenoid in the same patient. 4 However, no studies have con- ducted a comparative analysis between the flora of the surface and the core of both tonsils and adenoid in the same KEY WORDS: tonsillitis, adenoidectomy, antibiotics ABSTRACT A quantitative estimation of isolated bacteria from adenoid and tonsil tissues was carried out in 62 patients undergo- ing elective tonsillectomy and/or ade- noidectomy in a major medical center in Beirut, Lebanon. To determine the prevalent bacterial etiology of infections in these patients, the surface and core tissues were removed or excised from the adenoid and both tonsils and ana- lyzed by culture. Data showed that Haemophilus species were prevalent in these infections and most isolates were susceptible to tested antimicrobial agents. INTRODUCTION Upper airway obstruction secondary to chronic inflammation or hypertrophy of the adenoid and/or tonsils can lead to