Keratoconjunctivitis sicca attributable to parasympathetic facial nerve dysfunction associated with hypothyroidism in a horse

Schwarz, Bettina; Sallmutter, Tamara; Nell, Barbara

doi:10.2460/javma.233.11.1761

Cited by 41 publications

(27 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…11 Particular confusion surrounds the diagnosis and prevalence of primary hypothyroidism in adult horses. Thyroid disorders reported in the literature include nodular hyperplasia, 12 non-functional C-cell adenoma, [13][14][15] hyperthyroidism associated with thyroid neoplasia, [16][17][18] non-functional thyroid carcinoma, [19][20][21][22][23][24][25] idiopathic hypothyroidism 26 and…”

Section: Physiologymentioning

confidence: 99%

See 1 more Smart Citation

Quantitative Pertechnetate Thyroid Scintigraphy and the Ultrasonographic Appearance of the Thyroid Gland in Clinically Normal Horses

Davies

Barber

Crisman³

et al. 2010

Veterinary Radiology &Amp; Ultrasound

View full text Add to dashboard Cite

Abstract:The purpose of this study was to report the scintigraphic and sonographic appearance of the thyroid gland in clinically normal horses so these modalities could be used to assess the thyroid gland in this species. Horses were divided into two age groups. Group A consisted of 8 horses between 3 and 10 years of age and Group B of 7 horses between 11 and 20 years of age. Total T 4 concentrations were within the laboratory reference interval. Thyroid to salivary (T/S) ratio, percent dose uptake of pertechnetate and thyroid lobe volume were calculated. Echogenicity of thyroid lobes and presence of nodules were documented. The two groups were compared using appropriate parametric and nonparametic tests. Total T 4 concentrations were significantly lower in the older group. Sixty minute mean ± standard deviation (SD) T/S ratios for older versus younger horses were 5.8 ± 3.0 and 5.3 ± 2.2, respectively. Sixty minute median and interquartile ranges for percent dose uptake of pertechnetate for older versus younger horses were 3.64% (1.5 to 3.98%) and 2.55% (2.33 to 2.90%), respectively. Mean ± SD thyroid lobe volumes for older versus younger horses were 18.93 ± 5.16 cm 3 and 13.55 ± 3.56 cm 3 , respectively. Most thyroid lobes were hyper or isoechoic to the sternocephalicus muscle. Prevalence of thyroid nodules did not differ between groups. Older horses had trends for greater T/S ratios, percent dose uptakes and thyroid lobe volumes but had lower total T 4 concentrations. Further studies using scintigraphy and ultrasound in horses with thyroid disease are planned.

show abstract

Section: Physiologymentioning

confidence: 99%

“…26 At presentation the horse, a 6 year-old German (Saxon) Warmblood gelding was overweight and had a marked regional fat deposit over the crest of the neck. The horse also had moderate bilateral blepharospasm, bilateral hyperemic and edematous conjunctivas, and lusterless corneas.…”

mentioning

confidence: 99%

Quantitative Pertechnetate Thyroid Scintigraphy and the Ultrasonographic Appearance of the Thyroid Gland in Clinically Normal Horses

Davies

Barber

Crisman³

et al. 2010

Veterinary Radiology &Amp; Ultrasound

View full text Add to dashboard Cite

show abstract

“…In mature horses, thyroid dysfunction has been associated with anhydrosis (Breuhaus 2009) and equine metabolic syndrome, and sparse case reports have detailed hypothyroidism and hyperthyroidism (Ramirez et al . 1998; Schwarz et al . 2008; Tan et al .…”

Section: Introductionmentioning

confidence: 99%

Presumptive nonthyroidal illness syndrome in critically ill foals

Himler

Hurcombe

Griffin

et al. 2012

Equine Veterinary Journal

View full text Add to dashboard Cite

SummaryReasons for performing the study: Hypothalamic-pituitary-thyroid (HPT) axis dysfunction is associated with morbidity and mortality in critically ill people. To date, investigations of HPT axis in critically ill foals are limited. Objectives: To document the occurrence of low thyroid hormone concentrations (presumptive nonthyroidal illness syndrome; NTIS) in critically ill newborn foals and investigate whether NTIS is associated with severity of disease and outcome. Hypothesis: NTIS occurs frequently in foals with sepsis and is associated with sepsis score and outcome. Reverse T3 (rT3) concentrations will be increased in septic foals and highest in nonsurvivors. Methods: Thyroid hormones (total and free thyroxine [TT4 and fT4], total and free tri-iodothyronine [TT3 and fT3], reverse T3 [rT3]) were prospectively measured in healthy, sick nonseptic and septic foals. Clinical and laboratory information was retrieved from the medical records. Hormones were measured by validated radioimmunoassays. Results: Concentrations of all thyroid hormones except rT3 (P = 0.69) were decreased in septic and sick nonseptic foals (P<0.01). Reductions in hormone concentrations were associated with an increased sepsis score (P<0.01). Nonsurviving septic foals had lower TT4, fT4, TT3 and fT3 concentrations than surviving septic foals (P<0.01). rT3 concentrations were higher in nonsurviving septic premature foals than surviving septic premature foals (P<0.05). Conclusions: NTIS (euthyroid sick syndrome) is frequently observed in critically ill and premature foals, and associated with severity of disease and mortality. Potential relevance: More research is needed to better understand the mechanism of this finding and determine whether manipulation of the HPT axis or thyroid replacement therapy could be beneficial.

show abstract

“…Other reported causes include eosinophilic granulomatous dacryoadenitis and hypothyroidism. Determining the normal levels of tear secretion in healthy horses could be of help for the accurate diagnosis of KCS in this species [13, 17–19]. …”

Section: Resultsmentioning

confidence: 99%

Results of the Schirmer tear test performed with open and closed eyes in clinically normal horses

Trbolová

Ghaffari

2017

Acta Vet Scand

View full text Add to dashboard Cite

BackgroundThe Schirmer tear test (STT) is widely used in both human and veterinary ophthalmology. Two types of STTs have been developed: STT I and SST II. The STT I measures the basal and reflex tear production and is the most widely used STT. However, several factors influence the STT results such as the person performing the test and the location of the strip placement within the conjunctival sac. The aim of this study was to measure the basal and reflex tear production (STT I) in clinically normal horses with open versus closed eyes.ResultsForty clinically healthy horses without any ocular diseases were included. On day 1, the STT I was first performed on all the horses with the eyes open followed by an STT I with closed eyes performed 30 min later. On day 2, all horses had their eyes closed during the first STT and the eyes open during the second test performed 30 min later. The mean value of the STTs performed on open eye was significantly less than the STT performed on closed eye on both days of examination.ConclusionThis study showed a small but statistically significant difference between STT values obtained with open versus closed eyes in clinically normal horses.

show abstract

Keratoconjunctivitis sicca attributable to parasympathetic facial nerve dysfunction associated with hypothyroidism in a horse

Abstract: Hypothyroidism should be considered as a differential diagnosis in horses with peripheral neuropathy or keratoconjunctivitis sicca. In affected horses, administration of levothyroxine may lead to resolution of neurologic signs.

Cited by 41 publications

References 35 publications

Quantitative Pertechnetate Thyroid Scintigraphy and the Ultrasonographic Appearance of the Thyroid Gland in Clinically Normal Horses

Quantitative Pertechnetate Thyroid Scintigraphy and the Ultrasonographic Appearance of the Thyroid Gland in Clinically Normal Horses

Presumptive nonthyroidal illness syndrome in critically ill foals

Results of the Schirmer tear test performed with open and closed eyes in clinically normal horses

Contact Info

Product

Resources

About