AbstractsBiology & Animal Science

Peritonsillar abscess (PTA) is the most common otorhinolaryngological infection that requires special health care management. Its treatment varies greatly due to a lack of common clinical guidelines. Tonsillectomy (TE) is performed on a portion of PTA patients, yet it remains controversial as to which PTA patients would benefit from TE. Traditional bacterial culture is ineffective at defining the causative bacteria for PTA. Rapid microarray methods have been tested, for example on serum and joint fluid samples, but not yet on pus. Most of the bacteria found in PTA are susceptible to penicillin, but, to avoid complications, antibiotics, with unnecessary broad spectrum, are frequently used instead. The aim of the first study in this thesis was to explore the microbiology of adults with PTA using a modern identification method and to find cofactors among patients with different pathogens. Using a modern DNA-based microarray method, we examined the microbial findings in the pus aspirated from 180 PTA patients. Fusobacterium necrophorum proved to be the most prevalent bacteria, occurring more frequently in younger patients; group A Streptococcus was the second most common. The microarray method seemed to work well for identifying bacteria directly from pus. In the second study, the aim was to compare the treatment modalities for PTA in countries closely related to Finland. We sent an electronic questionnaire regarding PTA treatment to all central and university hospitals in Finland, Sweden, Norway and Denmark. The study revealed diversity among treatment modalities between the four countries. To identify factors predicting a doctor ́s decision for TE among PTA patients, in the third study, we retrieved data on 819 PTA patients from a national database, which included information on whether a TE was performed within five years after a PTA diagnosis and why. The study showed that young age and previous tonsillar infections increased the probability of having a TE performed. In the fourth study, the aim was to investigate whether combining metronidazole with penicillin enhances the recovery from PTA and whether metronidazole helps prevent PTA recurrences. A total of 200 prospectively collected patients were randomised to receive either penicillin and placebo or penicillin and metronidazole. The patients filled in an electronic diary daily for the first two weeks and then weekly for the following six weeks. Most patients (90 in each group) healed well without recurrence of PTA. Thus, metronidazole neither enhanced the recovery nor prevented recurrences; furthermore, it caused unwanted adverse effects (diarrhoea and nausea). These four explorations into PTA provided valuable insight. These results make a difference not just for one patient, but for the whole health care system; the treatment is evidence-based and can be offered to those whom it serves best. Kurkkupaise on tavallisin korva-, nenä- ja kurkkutautien sairaalahoitoa vaativa infektio. Sen hoitokäytännöt vaihtelevat huomattavasti. Osalta kurkkupaisepotilaista…