Pattern of bacterial pathogens of acute Otitis media in a tertiary hospital, South Western Nigeria

Introduction: Otitis media was reasonably prevalent prior to the use of antibiotics for treatment. In Nigeria, hospital incidence reports indicate that chronic suppurative Otitis media is the commonest. Complications that usually arise as a result of untreated Otitis media are meningitis, brain abscess, keratoma, otosclerosis, and hearing loss. The study aimed at providing information on the pattern of bacterial pathogens of acute Otitis media in LAUTECH Teaching hospital, Osogbo, Nigeria.Methods: It was a cross-sectional study involving patients with acute Otitis media attending ENT clinic at LAUTECH Teaching Hospital, Osogbo, Nigeria. Ear swabs were collected from the patients after informed consent. The samples were inoculated on general and selective laboratory media. Bacterial pathogens were isolated and identified. Antibiotic susceptibility testing was performed on each of the bacterial isolates using modified Kirby Bauer disk diffusion.Results: There were 115 isolates from 98 patients with acute Otitis media. Gram negative bacteria constituted 66.7% of the isolates. The most common organism was Pseudomonas aeruginosa (34.8%). Others were Staphylococcus aureus (30.4%), Proteus spp (15.7%), Klebsiella spp (11.3%), Escherichia coli (2.6%) and few Fungi (4.1%). Antibiotics sensitivity results of the isolates showed high resistance against most readily available antibiotics. The cumulative resistance of all the bacteria isolates to Augmentin was 89%, gentamicin 80%, ciprofloxacin 34% and ceftazidime 10%. About 88% of the Gram positive bacteria were resistant to penicillin G, amoxicillin, cotrimoxazole, and erythromycin. While 100% of the Gram negative bacteria were resistant to cotrimoxazole, tetracycline, and chloramphenicol. However, commonly isolated organisms were highly susceptible to few 3rd-generation cephalosporins especially ceftriaxone and ceftazidime.Conclusion: Based on the result of this study, it is suggested that knowledge of antibiotic profile of etiological agents in Otitis media would be of great advantage in reducing the morbidity and mortality associated with Otitis media.Keywords: Otitis media, Bacterial agents, Antibiotic resistanc

Detection of aggrecanase- and MMP-generated catabolic neoepitopes in the rat iodoacetate model of cartilage degeneration

AbstractObjectiveTo characterize the time course of aggrecan and type II collagen degradation in the rat iodoacetate model of cartilage degeneration in relationship to the temporal sequence that has been described in human osteoarthritis (OA).DesignRats were injected intra-articularly in one knee joint with iodoacetate and damage to the tibial plateau was assessed from digitized images captured using an image analyzer. The articular cartilage from the tibial plateau was harvested, extracted and glycosaminoglycan (GAG) content was measured using the dimethylmethylene blue (DMMB) assay. Cartilage aggrecan neoepitopes were detected in cartilage extracts by Western blotting using antibodies recognizing the aggrecanase-generated C-terminal neoepitope NITEGE (BC-13) and the MMP-generated C-terminal neoepitope DIPEN (BC-4). A type II collagen collagenase-generated neoepitope was detected in cartilage extracts by ELISA using the Col2-3/4Cshort antibody; denatured collagen was detected using the Col2-3/4m antibody.ResultsDegenerative joint changes and proteoglycan (GAG) loss progressed with time after iodoacetate injection. Western blotting of cartilage extracts of iodoacetate treated rats demonstrated an increase in both aggrecanase- and MMP-generated epitopes with the NITEGE aggrecanase neoepitope being significantly elevated on days 7, 14 and 21 while DIPEN the MMP neoepitope was significantly elevated on days 7 and 14. The type II collagen neoepitope recognized by Col2-3/4Cshort was significantly increased in cartilage extracts of rats at days 14 and 21 after iodoacetate injection.ConclusionThe proteoglycan fragments extracted from the knee cartilage of rats after the intra-articular injection of iodoacetate appeared to result from cleavage at both aggrecanase and MMP sites. Cleavage of type II collagen by collagenase was also detected after iodoacetate injection and occurred subsequent to the initiation of aggrecan loss. These observations serve to demonstrate similarities in the mechanisms of cartilage degeneration induced by iodoacetate to those seen in articular cartilage in OA