Use of positive contrast radiography to identify synovial involvement in horses with traumatic limb wounds.

BACKGROUND: The diagnostic value of positive contrast radiography in the work-up of suspected synovial infection in horses with limb wounds near synovial structures has yet to be systematically evaluated. OBJECTIVES: To determine the specificity, sensitivity and positive and negative predictive values of positive contrast radiography for identification of synovial infection in a population of horses with limb wounds. STUDY DESIGN: Retrospective case study comparing the performance of positive contrast radiography to the gold standard of synovial fluid cytology in horses presenting with limb wounds in the vicinity of synovial structures. METHODS: Case records of horses presenting to the Royal Veterinary College Equine Hospital between 2010 and 2015 with limb wounds that may have compromised adjacent synovial structures were analysed. Synovial fluid cytology results were used to categorise synovial structures in infected and noninfected groups. Positive contrast radiography results were compared between infected and noninfected groups and sensitivity, specificity, positive and negative predictive values were calculated. RESULTS: Fifty horses with 66 synovial structures were included in the study. Positive contrast radiography had a high specificity (86.4%), but only a moderate sensitivity (59.1%) for the identification of synovial infection. In addition, a low positive predictive value (68.4%) and high negative predictive value (80.9%) were observed in this population of horses. MAIN LIMITATIONS: Sensitivity, specificity and predictive values may differ between different synovial structures and cases. Different conclusions may be drawn from the results in a single population. Sensitivity and specificity of positive contrast radiography may also be influenced by different techniques used by examiners and by inherent characteristics of individual cases. CONCLUSIONS: Positive contrast radiography should be used for the investigation of potential synovial infection in horses with limb wounds, particularly if no synovial fluid sample for laboratory analysis can be obtained. However, it appears that positive contrast radiography is best used in combination with other tests to ensure that a correct and timely diagnosis is made.

Pharmacokinetics of once-a-day netilmicin (4.5 mg/kg) in neonates.

The pharmacokinetics of once-a-day netilmicin (4.5 mg/kg) was studied in 16 neonates, divided for analysis into three groups according to gestational age: group 1 >36 weeks (n=7); group II between 34-36 weeks (n=4); and group III <34 weeks (n=5). The serum netilmicin (mean +/- SD) 4h and 24h after the first dose were 4.7 +/- 0.8 and 0.8 +/- 0.5 mg/L; 4.9 +/- 0.8 and 1.9 +/-0.2 mg/L; 4.9 +/- 0.5 and 1.7 +/- 0.5 mg/L in groups I, II and III respectively. After the second dose, concentrations at 2, 4, 8, 16 and 24 h were 7.2 +/- 1.0, 5.0 +/- 0.8, 3.0 +/- 0.6, 1.7 +/- 0.4 and 0.9 +/- 0.2 mg/L (group I); 8.6 +/- 0.2, 6.1 +/- 0.5, 4.2 +/- 0.7, 2.6 +/- 0.1 and 1.4 +/- 0.4 mg (group II); 9.0 +/- 1.2, 6.3 +/- 0.9, 4.1 +/- 0.7, 2.6 +/- 0.5 and 1.7 +/- 0.3 mg/L (group III). There was a large degree of inter-patient variability in serum concentrations and serum half-life (t1/2), volume of distribution (VD), area-under-the-curve (AUC), relative serum clearance (Clp) such that these parameters could not be correlated to age or weight. Absolute serum clearance (L/h) was correlated with gestational age (r = 0.672, P <0.01). There was no statistically significant evidence of accumulation between the first and second doses for any patient group. One baby from each group II and group III had concentration >2 mg/L 24h after the first dose and one baby from group III had concentration >2 mg/L 24h after the second dose. There are no established correlations between serum netilmicin concentrations and efficacy or toxicity in neonates and keeping 24 h trough concentration below 2 mg/L with a once-a-day dose of 4.5 mg/L would have to be validated in terms of its clinical efficacy and potential toxicity in a neonatal population.

Neonatal flumazenil therapy reverses maternal diazepam.

A woman at 32 weeks' gestation with eclampsia was given 120 mg diazepam shortly before emergency caesarean section. The infant had persistent apnoea and required respiratory support. Spontaneous respiration began after intravenous flumazenil infusion was started. Diazepam and its active metabolites were assayed during and after 5 d of treatment with flumazenil.

Severe burns resulting from an exploding teat on a bottle of infant formula milk heated in a microwave oven.

Accidental injury to infants can result from the use of home microwave ovens. The spectrum of injury includes scald burns of the trachea, palate oropharynx and oesophagus due to aspiration and ingestion of foods that have been overheated. There is one previous case report of a child with second-degree burns of 6 per cent of his body area due to explosion of the plastic liner and nipple on a feeding bottle top. We present a case report of an infant who suffered 7 per cent full-thickness burns following explosion of the bottle teat and subsequent splattering with hot milk. He required mid-palmar amputation of his left hand including thumb, index and middle fingers. The full-thickness burns of left cheek and left shoulder were grafted but will result in significant scarring. It is common practice in many homes to heat infant feeds in the microwaves. We suggest that health professionals dealing with children need to be aware of the potential hazards so that appropriate education of parents can take place.