Background: Early exposure of infants and long-term immunity suggest that colonization with Moraxella catarrhalis is more frequent than is determined by routine culture. We characterized a reservoir of M. catarrhalis in pharyngeal lymphoid tissue.
Methods: Tissue from 40 patients (median age, 7.1 years) undergoing elective tonsillectomy and/or adenoidectomy was analyzed for the presence of M. catarrhalis by culture, real-time DNA and RNA polymerase chain reaction (PCR), immunohistochemical analysis (IHC), and fluorescent in situ hybridization (FISH). Histologic sections were double stained for M. catarrhalis and immune cell markers, to characterize the tissue distribution of the organism. Intracellular bacteria were identified using confocal laser scanning microscopy (CLSM).
Results: Twenty-nine (91%) of 32 adenoids and 17 (85%) of 20 tonsils were colonized with M. catarrhalis. Detection rates for culture, DNA PCR, RNA PCR, IHC, and FISH were 7 (13%) of 52, 10 (19%) of 52, 21 (41%) of 51, 30 (61%) of 49, and 42 (88%) of 48, respectively (P<.001). Histologic analysis identified M. catarrhalis in crypts, intraepithelially, subepithelially, and (using CLSM) intracellularly. M. catarrhalis colocalized with macrophages and B cells in lymphoid follicles.
Conclusions: Colonization by M. catarrhalis is more frequent than is determined by surface culture, because the organism resides both within and beneath the epithelium and invades host cells.
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http://dx.doi.org/10.1086/521194 | DOI Listing |
Int Ophthalmol
December 2024
Department of Ophthalmology, University of Health Sciences, Ankara Bilkent City Hospital, Ankara, Turkey.
Purpose: To evaluate the role of Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae, Serratia marcescens, and Moraxella catarrhalis in the nasal and ocular surface flora, along with their metabolic activities in children with unilateral congenital nasolacrimal duct obstruction (CNLDO).
Methods: Swabs were taken from the bilateral inferior meatus and ocular surface of 26 children with unilateral CNLDO before probing. Nasal and ocular surface swabs from non-operated eyes of children who underwent unilateral blepharoptosis or strabismus surgery formed the control group.
BMC Infect Dis
November 2024
Department of Medical Laboratory Science, College of Medicine and Health Sciences, Wollo University, P.O. Box: 1145, Dessie, Ethiopia.
Arch Biochem Biophys
January 2025
Department of Biosciences and Bioengineering, IIT Roorkee, Roorkee, India. Electronic address:
Eur J Clin Microbiol Infect Dis
November 2024
Department of Respiratory Medicine, Children's Hospital of Soochow University, Suzhou, China.
Background: The coronavirus disease 2019 (COVID-19) pandemic has caused significant changes in lower respiratory tract infections (LRTIs). This study aimed to characterize potentially pathogenic bacterial infections in paediatric patients hospitalized for LRTIs per-, during and post-COVID-19.
Methods: Sputum culture data from 85,659 children with LRTIs at the Children's Hospital of Soochow University from January 2016 to May 2024 were analyzed for eight bacteria: Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Moraxella catarrhalis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii.
Sci Rep
November 2024
Department of Radiation Oncology, Akdeniz University School of Medicine, Antalya, Turkey.
Healthcare-associated infections (HAIs) remain a critical public health issue, as they contribute to prolonged treatment duration, increased healthcare costs, and heightened risks of morbidity and mortality. In head and neck cancer patients undergoing radiotherapy, thermoplastic masks (TMs), which come into direct contact with the skin, represent a potential vector for infection. Additionally, the storage racks where these masks are kept may also facilitate microorganism transmission.
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