Plasma serotonin in horses undergoing surgery for small intestinal colic.

This study compared serotonin concentrations in platelet poor plasma (PPP) from healthy horses and horses with surgical small intestinal (SI) colic, and evaluated their association with postoperative ileus, strangulation and non-survival. Plasma samples (with EDTA) from 33 horses with surgical SI colic were collected at several pre- and post-operative time points. Serotonin concentrations were determined using liquid-chromatography tandem mass spectrometry. Results were compared with those for 24 healthy control animals. The serotonin concentrations in PPP were significantly lower (P < 0.01) in pre- and post-operative samples from surgical SI colic horses compared to controls. However, no association with postoperative ileus or non-survival could be demonstrated at any time point. In this clinical study, plasma serotonin was not a suitable prognostic factor in horses with SI surgical colic.

Sérotonine plasmatique chez des chevaux subissant une chirurgie pour des coliques du petit intestin. Cette étude a comparé les concentrations de sérotonine dans le plasma faible en plaquettes (PFP) de chevaux en santé et de chevaux atteints de coliques chirurgicales du petit intestin et a évalué leur association avec l'occlusion intestinale postopératoire, la strangulation et la non-survie. Des échantillons de plasma (avec EDTA) ont été prélevés auprès de 33 chevaux atteints de coliques du petit intestin à plusieurs moments préopératoires et postopératoires. Les concentrations de sérotonine ont été déterminées à l'aide d'un spectromètre de masse LC-ESI-MS/MS. Les résultats ont été comparés avec ceux de 24 animaux témoins en santé. Les concentrations de sérotonine du PFP étaient significativement inférieures (P < 0,01) dans les échantillons préopératoires et postopératoires provenant des chevaux atteints de coliques du petit intestin comparativement aux animaux témoins. Cependant, aucune association avec l'occlusion intestinale postopératoire ou la non-survie n'a pu être démontrée à aucun moment. Dans cette étude clinique, la sérotonine plasmatique ne s'est pas avéré un facteur de pronostic approprié chez les chevaux atteints de coliques chirurgicales du petit intestin.(Traduit par Isabelle Vallières).

Flecked retina, choroidopathy, and retinal pigment epithelial tear in familial pulmonary arterial hypertension.

BACKGROUND: Thanks to advancement in treatment modalities, the medial survival rate of patients with familial pulmonary arterial hypertension (FPAH) has been improved. Unfortunately, ocular complications because of the chronically elevated systemic venous pressure become more frequent. METHODS: The authors report new FPAH-associated fundus changes in a 50-year-old male patient treated with sildenafil. The anomalies were studied with autofluorescence, fluorescein and indocyanine green angiography, and spectral optical coherence tomography including enhanced depth imaging. RESULTS: Loss of vision and cystoid macular edema were associated with a flecked retina, a thick choroid, central serous choroidopathy-like changes in both eyes and with retinal pigment epithelium detachments and a retinal pigment epithelium tear in the right eye. CONCLUSION: Treatment of ocular findings associated with FPAH mainly involves optimal control of pulmonary arterial hypertension and ophthalmic supportive treatment toward preventing acute ocular complications. The ocular complications occur as a result of enhanced pressure in the superior vena cava and in the ophthalmic veins, resulting in dilation of the ocular veins and congestion of the choroid. Sildenafil treatment in FPAH may enhance the congestion of the choroid and can induce central serous choroidopathy-like changes. A flecked retina, central serous choroidopathy-like changes, and retinal pigment epithelium tear are rare complications of FPAH.

Comparative analysis of serotonin in equine plasma with liquid chromatography--tandem mass spectrometry and enzyme-linked immunosorbent assay.

Serotonin is regularly measured in equine platelet-poor plasma in research settings. However, reported reference values vary between studies, partially because plasma serotonin concentrations are very low and a reliable and affordable detection method is lacking. A simple, rapid, and sensitive method for serotonin determination in equine platelet-poor plasma using liquid chromatography--tandem mass spectrometry (LC-MS/MS) was developed and validated. Results of a commercially available enzyme-linked immunosorbent assay (ELISA) were compared to the LC-MS/MS results, in order to validate a test more suitable for use in a clinical situation. For LC-MS/MS, 500 µl of plasma was required, and deuterated serotonin was used as an internal standard. The sample preparation was based upon a simple liquid extraction into ethyl acetate. Chromatographic separation was performed with an acetic acid--acetonitrile mobile phase gradient elution. Linearity was demonstrated between 3 ng/ml and 100 ng/ml. A limit of quantification of 3 ng/ml was achieved, corresponding to a limit of detection of 0.10 ng/ml. Comparison of LC-MS/MS and ELISA with Passing-Bablok regression and Bland--Altman plotting showed a poor agreement between the 2 methods, with an increasing difference within the higher range of measurements. Caution is needed when extrapolating results from sources using different analytical techniques.

European outbreak of atypical myopathy in the autumn 2009.

BACKGROUND: Atypical myopathy is an acute, severe rhabdomyolysis occurring in grazing horses. In the beginning of October 2009, a new outbreak occurred in several European countries. Geographic, demographic and clinical data of the reported cases in the month October 2009 are described. KEY FINDINGS: The survival rate in this outbreak was 25%. The most frequently observed clinical signs were congested mucous membranes, dyspnea, tachycardia, depression, weakness, stiffness, recumbency, trembling, sweating, and myoglobinuria. Nonsurvivors were significantly more likely to be recumbent than survivors. Prognostic factors, symptomatic treatment, and preventive measures are discussed. SIGNIFICANCE: Differences were encountered during the described outbreak of atypical myopathy in October 2009 compared with previous outbreaks reported. Equine practitioners should be aware that previous epidemiological studies have shown that after a high prevalence in the autumn, new cases are likely to occur in the following spring.

Risk factors for incisional complications after exploratory celiotomy in horses: do skin staples increase the risk?

OBJECTIVE: To assess risk factors for celiotomy incisional infection in horses, especially the use of staples for skin closure. STUDY DESIGN: Case series. ANIMALS: Horses (n=356) that had 1 exploratory celiotomy for colic and survived >2 weeks after surgery between March 1, 2004 and December 31, 2007. METHODS: Incisions were classified as "normal" (no complication, only edema, serous drainage lasting <24 hours) or as "surgical site infection (SSI)" (persistent serosanguinous drainage or purulent drainage with or without positive bacterial culture). All possible risk factors, including method of skin closure (monofilament sutures or staples), were statistically analyzed using univariate and multivariate logistic regression. RESULTS: Of 356 horses, 303 (85%) had normal wound healing and 53 (15%) developed a SSI (purulent: 48 [14%]; persistent serosanguinous: 5 [1%]). Bacterial cultures were positive in 33 of 40 cases. Factors significantly associated with SSI in the multivariate analysis were: use of staples for skin closure (odds ratio [OR] 3.85, P<.001) and surgical site closure by a 1st or 2nd year resident (OR 2.20, P=.016). Lavage of the linea alba with sterile saline solution after closure was a protective factor (OR 0.38, P=.004). CONCLUSION: Use of staples for skin closure and less experienced surgeons closing the abdomen are risk factors for incisional infection. Incisional lavage after linea alba closure was a protective factor. CLINICAL RELEVANCE: Despite their ease and speed of application, skin staples can lead to an increase in celiotomy wound complications in horses.