Otitis

Abstract: Pseudomonas aeruginosa has emerged as an important pathogen during the past two decades. It causes between 10% and 20% of infections in most hospitals. Pseudomonas infection is especially prevalent among patients with burn wounds, cystic fibrosis, acute leukemia, organ transplants, and intravenous-drug addiction. P. aeruginosa is a common nosocomial contaminant, and epidemics have been traced to many items in the hospital environment. Patients who are hospitalized for extended periods are frequently colonized by this organism and are at increased risk of developing infection. The most serious infections include malignant external otitis, endophthalmitis, endocarditis, meningitis, pneumonia, and septicemia. The likelihood of recovery from pseudomonas infection is related to the severity of the patient's underlying disease process. The introduction of the antipseudomonal aminoglycosides and penicillins has improved substantially the prognosis of these infections. Ticarcillin and carbenicillin have been especially beneficial in neutropenic patients; however, prompt institution of therapy is mandatory for optimal benefit. Many new drugs with antipseudomonal activity, including penicillins, cephalosporins, and other beta-lactams, have been introduced in recent years and offer the potential for new approaches to therapy for these infections.

Abstract: Background Otitis media (OM) is a leading cause of health care visits and drugs prescription. Its complications and sequelae are important causes of preventable hearing loss, particularly in developing countries. Within the Global Burden of Diseases, Injuries, and Risk Factors Study, for the year 2005 we estimated the incidence of acute OM, chronic suppurative OM, and related hearing loss and mortality for all ages and the 21 WHO regional areas.

Abstract: ContextChronic otitis media (OM) is a common pediatric infectious disease. Previous studies demonstrating that metabolically active bacteria exist in culture-negative pediatric middle-ear effusions and that experimental infection with Haemophilus influenzae in the chinchilla model of otitis media results in the formation of adherent mucosal biofilms suggest that chronic OM may result from a mucosal biofilm infection.ObjectiveTo test the hypothesis that chronic OM in humans is biofilm-related.Design, Setting, and PatientsMiddle-ear mucosa (MEM) biopsy specimens were obtained from 26 children (mean age, 2.5 [range, 0.5-14] years) undergoing tympanostomy tube placement for treatment of otitis media with effusion (OME) and recurrent OM and were analyzed using microbiological culture, polymerase chain reaction (PCR)-based diagnostics, direct microscopic examination, fluorescence in situ hybridization, and immunostaining. Uninfected (control) MEM specimens were obtained from 3 children and 5 adults undergoing cochlear implantation. Patients were enrolled between February 2004 and April 2005 from a single US tertiary referral otolaryngology practice.Main Outcome MeasuresConfocal laser scanning microscopic (CLSM) images were obtained from MEM biopsy specimens and were evaluated for biofilm morphology using generic stains and species-specific probes for H influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis. Effusions, when present, were evaluated by PCR and culture for evidence of pathogen-specific nucleic acid sequences and bacterial growth, respectively.ResultsOf the 26 children undergoing tympanostomy tube placement, 13 (50%) had OME, 20 (77%) had recurrent OM, and 7 (27%) had both diagnoses; 27 of 52 (52%) of the ears had effusions, 24 of 24 effusions were PCR-positive for at least 1 OM pathogen, and 6 (22%) of 27 effusions were culture-positive for any pathogen. Mucosal biofilms were visualized by CLSM on 46 (92%) of 50 MEM specimens from children with OME and recurrent OM using generic and pathogen-specific probes. Biofilms were not observed on 8 control MEM specimens obtained from the patients undergoing cochlear implantation.ConclusionDirect detection of biofilms on MEM biopsy specimens from children with OME and recurrent OM supports the hypothesis that these chronic middle-ear disorders are biofilm-related.

Abstract: A natural history study of pneumococcal infection in 82 infants followed from birth is reported. Longitudinal carriage patterns were determined by serial throat and nasopharyngeal cultures. Seventy-nine of 82 infants carried one or more types during the study period. The first type was acquired by a mean age of six months, and the duration of carriage decreased with successive types carried. Acquisition of new types peaked in winter months, but carriage rates fluctuated throughout the year. Thirty-one pneumococcal infections were documented in 24 infants: 28 episodes of otitis media, two of bacteremia, and one of meningitis. Types causing disease were similar to commonly carried types (6, 14, 19 and 23). However, infection usually occurred within one month of acquisition of a new type and was seldom associated with prolonged carriage. In terms of exposure to new strains, 15% (31 of 196) of acquisitions resulted in disease.