Transmission electron microscopy (TEM) analysis of ciliary ultrastructure is classically used for the diagnosis of primary ciliary dyskinesia (PCD). We report our extensive experience of TEM analysis in a large series of patients in order to evaluate its feasibility and results.TEM analysis performed in 1,149 patients with suspected PCD was retrospectively reviewed. Biopsies (1,450) were obtained from nasal (44%) or bronchial (56%) mucosa in children (66.5%) and adults (33.5%).TEM analysis was feasible in 71.4% of patients and showed a main defect suggestive of PCD in 29.9%. TEM was more feasible in adults than in children, regardless of the biopsy site. Main defects suggestive of PCD were found in 76.9% of patients with sinopulmonary symptoms and in only 0.4% of patients with isolated upper and 0.4% with isolated lower respiratory tract infections. The defect pattern was similar in children and adults, involving dynein arms (81.2%) or central complex (CC) (18.8%). Situs inversus was never observed in PCD patients with CC defect. Kartagener syndrome with normal ciliary ultrastructure was not an exceptional condition (10.2% of PCD).In conclusion, TEM analysis is feasible in most patients and is particularly useful for PCD diagnosis in cases of sinopulmonary syndrome of unknown origin.
We conducted a multicenter prospective study to document changes in nasopharyngeal carriage of Streptococcus pneumoniae, Haemophilus influenzae, and Branhamella catarrhalis during antibiotic therapy. A cohort of 629 children with respiratory tract infections underwent nasopharyngeal sampling before and after antibiotic treatment. Susceptibility testing, serotyping, arbitrarily primed polymerase chain reaction, and pulsed-field gel electrophoresis were used to compare pretreatment and posttreatment strains of S. pneumoniae. A significant decrease in carriage of all 3 species (especially S. pneumoniae and B. catarrhalis) was recorded. The increase in the proportion of penicillin-resistant pneumococci (PRP; 66% vs. 44%) was due to the decreased carriage of penicillin-susceptible pneumococci (71 of 629 vs. 176 of 629). The risk of PRP carriage in a given child did not increase. None of the children was found to harbor genetically related strains with increased minimum inhibitory concentrations. Given the multiple resistance of PRP, beta-lactam antibiotic therapy also increased the incidence of macrolide-resistant strains, whereas macrolides selected both macrolide- and penicillin-resistant strains.
These data illustrate that antibiotic therapy did not increase the rate at which children carried penicillin-resistant S. pneumoniae, but there was an increase in the rate of resistance among the children carrying pneumococci at the end of the treatment, mainly as a result of reduction of susceptible strains.
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