Experience overrides colour in lizard contests

We examined the role of conspicuous coloration in male-male contests for two species of Australian dragon lizards, Ctenophortis decresii and C. vadnappa, in which conspicuous coloration has a demonstrated predation cost. We conducted contests in which the overall conspicuousness of male coloration was manipulated using paints that matched the spectral reflectance of the lizards, as well as natural (control) contests. There was little evidence for an influence of colour on contest outcome or aggression levels for either species when all experiments were considered. However, we found a significant effect of trial order and experience on contest outcome and aggression levels (the same pair of males was used for both types of contest), despite a 2-3 week interval between contests. When we examined only the first trial between unfamiliar males, we found that male C. vadnappa that had been painted to appear more conspicuous consistently won. Comparison with the natural trials suggests that the aspect of colour manipulation that was responsible for this result was the 'hue' of the throat: males with yellower throats consistently beat males with bluer throats in both natural and painted trials. The difference in coloration of flank markings also predicted the difference in aggression scores between contestants in the natural trials. These results suggest that although colour is important in opponent assessment and in determining contest outcome in C vadnappa, previous agonistic experience can override the effects of colour and have a long-lasting influence on aggressive behaviour.

Realtime telemedicine for paediatric otolaryngology pre-admission screening

We conducted a feasibility study to examine whether a paediatric patient at a regional hospital could be assessed by an ear, nose and throat (ENT) specialist via videoconference, therefore saving at least one journey to the tertiary hospital for a pre-admission appointment. A video-otoscope was used with standard videoconference equipment, and realtime images were transmitted at a bandwidth of 384 kbit/s. In all, 13 telepaediatric ENT clinics were conducted between November 2003 and April 2005, and 98 consultations were facilitated for 64 patients. The main reasons for referral were recurrent tonsillitis (25%) and obstructive sleep apnoea (23%). Of the 64 patients examined by telemedicine, 42 (66%) were recommended for surgery and placed on the surgical waiting list. About 12 patients (19%) required travel to the tertiary centre for further investigations and tests not available locally, while four patients (6%) were reviewed via videoconference during a scheduled clinic. Six patients (9%) required no further follow-up after their initial telepaedliatric consultation. Videoconferencing is an effective method of assessing ENT conditions of paediatric patients and for pre-screening potential surgical admissions to a tertiary hospital. Careful consideration of a number of economic and logistical factors needs to be made before large investments are made to expand the service.

Parvovirus B19 infection presenting as 'bathing trunk' erythema with pustules

A 7-year-old girl presented with acute vulval erythema and pustules, associated with a petechial eruption in her flexures and over her feet. There was a mild prodromal illness and the patient was afebrile. There were minimal symptoms associated with the rash. Skin and throat swabs were negative and blood examination showed mild neutrophilia and lymphopaenia. Parvovirus B19 IgM was detected on serology and cutaneous features resolved within 4 days. This is a further case of parvovirus B19 infection presenting as a 'bathing trunk' exanthem that has unique dermatologic features, including the presence of pustules and distant petechiae. © 2006 The Australasian College of Dermatologists.

Predictors of an antibiotic prescription by GPs for respiratory tract infections: a pilot

Background. Antibiotics are over-prescribed for respiratory tract infections in Australia. Objectives. The aim of this study was to describe the clinical predictors of GPs' prescribing of antibiotics. Methods. We used Clinical Judgment Analysis to study the responses of GPs to hypothetical paper-based vignettes of a 20-year-old with a respiratory tract infection. The nature of four symptoms and signs (colour of nasal mucous discharge; soreness of the throat; presence of fever; and whether any cough was productive of sputum) was varied and their effect on prescribing measured using logistic regression. Results. Twenty GPs participated. The nature of each symptom and sign significantly predicted prescribing of an antibiotic. Cough productive of yellow sputum; presence of sore throat; fever; and coloured nasal mucus increased the probability of an antibiotic being prescribed. Conclusions. GPs are influenced by clinical signs and symptoms to use antibiotics for respiratory infections for which there is poor evidence of efficacy from the literature.