犬糖尿病并发甲状腺机能减退症的诊断与治疗

为对一例临床症状为多饮多尿,逐渐消瘦,双眼白内障,背部毛稀疏的患犬进行确诊,经临床检查和实验室检查(血常规、生化、尿常规、糖化血红蛋白、甲状腺功能检查),血糖(GLU)399mg/dL(参考范围70mg/dL~143mg/dL),确诊为糖尿病并发甲状腺机能减退症。经胰岛素控制血糖,同时补充甲状腺素片治疗甲状腺机能减退,再结合辅助治疗,病情得到控制。     

犬甲状腺、甲状旁腺机能紊乱症的诊疗

1甲状腺机能减退甲状腺机能减退是由于甲状腺激素合成或分泌不足，导致犬全身活动呈现进行性减退的疾病。临床上犬比猫多发。原发性甲状腺机能减退，病初犬易疲劳，嗜睡，惧冷，脑反应迟钝，体重增加，甚至呕吐或腹泻。皮毛干燥，被毛呈对称性大量脱落，再生延迟，皮肤色素增多，出现皮脂溢和瘙痒。眼睑下垂，外貌丑陋，母犬乏情，公犬睾丸萎缩。继发性甲状腺机能减退，多由肿瘤引起，临床上以沉郁、嗜睡、厌食、运动失调和癫痫发作等神经症状为主。第三种甲状腺机能减退，     

26例犬甲状腺机能减退的临床调查分析

收集了浙江大学附属动物医院门诊26例犬甲状腺机能减退的病例相关资料,通过对其性别、品种、年龄、临床症状和部分血液生化结果进行调查分析,治疗采用口服左旋甲状腺素片20μg/kg,2次/d。结果表明,犬甲状腺机能减退没有性别倾向性,2岁~7岁的中青年犬易发,涉及11个品种;患犬均有不同程度的肥胖、反应迟钝的症状,此外因频繁抽搐服用抗癫痫药物(苯巴比妥)导致甲状腺功能低下的犬3例,仅表现葡萄膜炎的犬2例,并发糖尿病的犬1例,表现为脱毛、色素沉着、继发感染等皮肤异常的犬20例;患犬高胆固醇血症的占15.38%,高甘油三酯血症的占65.38%;给予口服左旋甲状腺素片治疗效果良好。     

犬糖尿病的发病原因及防治措施

犬糖尿病是一种以高血糖为典型特征的代谢障碍性疾病,该病主要是由于胰腺β-细胞损伤,引起分泌胰岛素的功能下降,导致胰岛素分泌不足和胰岛素拮抗。机体血糖和尿糖水平增加时,胰岛素不能正常效应,导致出现糖尿病。现主要介绍犬糖尿病的分类、发病原因、临床症状以及防治措施,以期为降低犬糖尿病的发病率提供参考。     

13例犬疑似甲状腺机能减退性疾病临床调查分析

正犬甲状腺机能减退症又称犬甲减。主要是由于犬自身甲状腺功能或结构出现了异常,引起机体分泌和合成甲状腺激素不足导致犬身体机能代谢效率降低的一类疾病。犬甲减是导致犬内分泌紊乱的重要疾病。临床上甲减患犬常表现出嗜睡、精神浑沌、运动机能减退、皮肤干燥无光伴有色素化、被毛脱落     

1例犬甲状腺肿瘤的诊治

通过临床症状、血常规、生化、X光片、病理切片等检查方法,确诊该犬贫血、甲状腺功能紊乱、机能减退,手术进行甲状腺肿瘤切除(甲状腺肿瘤属于滤泡性甲状腺瘤)。经手术治疗后几天症状好转(暂时没有转移),正常饮食,说明外科手术是治疗甲状腺肿瘤的有效方法。     

犬甲状腺机能减退不同诊断方法的优缺点

在阐述了犬甲状腺机能减退各种诊断方法诊断原理的基础上,从内分泌学诊断、影像学诊断、遗传学诊断和治疗性诊断4个方面,对犬甲状腺机能减退诊断方法研究成果进行了概述,归纳了不同方法的优缺点,并分析了原因。指出:单独使用一种诊断方法对犬甲状腺机能减退进行诊断不够准确,目前内分泌学诊断是主要的诊断方法,根据患犬血清总四碘甲腺原氨酸(TT4)、游离四碘甲腺原氨酸(FT4)和促甲状腺素(TSH)浓度测定结果,结合病史与临床症状,可对绝大多数甲状腺机能减退病例作出诊断。     

犬髌骨脱位的诊断和治疗

为了对一例右后肢呈间歇性跛行的患犬进行确诊,经临床检查,实验室检查(血常规和血液生化检查)和影像学检查进行诊断。触诊右后肢髌骨位置异常,白细胞总数21.7×10~9/L(参考范围5.5×10~9/L～19.5×10~9/L)和粒细胞数19.01×10~9/L(参考范围2.8×10~9/L～13.0×10~9/L),肌酸激酶2 072 U/L(参考范围90 U/L～440 U/L),X光片显示右侧髌骨内方脱位,确诊为右后肢髌骨内方脱位。经滑车楔形切除术和胫骨结节移位术治疗,1个月后患犬痊愈。     

一例犬肾上腺皮质机能减退的病例报告

通过对一例犬肾上腺皮质机能减退病例进行全面的检查,对病史、临床表现和实验室检查结果进行分析,做出诊断与治疗。本报告为犬肾上腺皮质机能减退的临床诊疗提供参考。     

3例犬糖尿病并发胰岛素抵抗的诊断与治疗

为了更好地了解糖尿病患犬并发胰岛素抵抗的诊治,试验对3例确诊为糖尿病病例的诊疗过程进行回顾,对其临床症状、诊断、治疗和预后等方面予以分析。结果表明:3例患犬在用胰岛素治疗时均存在胰岛素抵抗,血糖控制不理想,详细检查后发现,患犬同时并发甲状腺机能减退症或库兴氏综合征,在针对并发症治疗后,血糖水平逐渐趋于稳定。说明在用胰岛素治疗糖尿病患犬时,若血糖控制不理想,需要进一步检查是否存在胰岛素抵抗的情况并进行治疗,进而才能更好地控制血糖。     

Evaluation of the thyroid status of Basenji dogs in Australia

Objective To determine the thyroid status of Basenji dogs in Australia. Methods Jugular or cephalic venipuncture blood samples were taken from 113 Basenji, comprising 47 males, 5 castrates, 48 entire and 13 spayed bitches, and sent on ice in plain and EDTA tubes to a single laboratory to determine haematocrit and serum concentrations of total thyroid hormone (thyroxine, TT4), thyroid‐stimulating hormone (TSH) and cholesterol. In a subgroup of 8 dogs with abnormal elevated TSH concentrations and subnormal TT4 concentrations, 5 were further examined by dynamic endocrine testing using recombinant human (rh) TSH (54 µg). Results Ages ranged from 1 to 14 years and weight range was 6.5 to 14.0 kg. TT4 concentrations (nmol/L) ranged from 2 to 27, with a median of 13 and a mean ± SD of 13.0 ± 5.7. Importantly, 85/113 (75%) of TT4 values were lower than the normal laboratory reference range (17–37). TSH concentrations (ng/mL) ranged from 0.05 to 5.37, with a median of 0.16 and a mean ± SD of 0.3 ± 0.6. Conclusions Basenji have a similar reference range for serum TSH, but a considerably lower reference range for TT4 (2–27 nmol/L) than most breeds and crossbreds, resembling the sight hounds in this respect. Given the difficulty of accurately measuring TT4 concentrations that are so low, concomitant serial TSH determinations are essential to properly asses thyroid function. Taken alone, TT4 determinations are only of use when the value is within the reference range, in which case a diagnosis of hypothyroidism is likely excluded.     

Assessment of the value of quantitative thyroid scintigraphy for determination of thyroid function in dogs

Objective : To assess the value of thyroid scintigraphy to determine thyroid status in dogs with hypothyroidism and various non‐thyroidal illnesses. Methods : Thyroid hormone concentrations were measured and quantitative thyroid scintigraphy performed in 21 dogs with clinical and/or clinicopathological features consistent with hypothyroidism. Results : In 14 dogs with technetium thyroidal uptake values consistent with euthyroidism, further investigations supported non‐thyroidal illness. In five dogs with technetium thyroidal uptake values within the hypothyroid range, primary hypothyroidism was confirmed as the only disease in four. The remaining dog had pituitary‐dependent hyperadrenocorticism. Two dogs had technetium thyroidal uptake values in the non‐diagnostic range. One dog had iodothyronine concentrations indicative of euthyroidism. In the other, a dog receiving glucocorticoid therapy, all iodothyronine concentrations were decreased. Markedly asymmetric technetium thyroidal uptake was present in two dogs. All iodothyronine concentrations were within reference interval but canine thyroid stimulating hormone concentration was elevated in one. Non‐thyroidal illness was identified in both cases. Clinical Significance : In dogs, technetium thyroidal uptake is a useful test to determine thyroid function. However, values may be non‐diagnostic, asymmetric uptake can occur and excess glucocorticoids may variably suppress technetium thyroidal uptake and/or thyroid hormone concentrations. Further studies are necessary to evaluate quantitative thyroid scintigraphy as a gold standard method for determining canine thyroid function.     

Impairment in the pituitary-thyroid axis of the Camelus dromedarius infected with Trypanosoma evansi

Camels infected with Trypanosoma evansi were diagnosed by the Passive Haemagglutination Test and Ag-ELISA and subjected to hormonal blood analyses to estimate the function of the thyroid gland. The results indicated that T. evansi caused a significant case of hypothyroidism evidenced as a decrease in the thyroid triiodothyronine (T3) and thyroxine (T4) blood levels associated with a parallel decrease in the level of blood pituitary thyrotropic hormone (TSH) as measured by the RIA technique.     

Is it possible to diagnose canine hypothyroidism?

A definitive diagnosis of hypothyroidism can be difficult because of the many clinical abnormalities associated with thyroid hormone deficiency, and the lack of readily available diagnostic tests with high sensitivity and specificity. Thyroid function tests should be performed only in dogs with clinical findings consistent with hypothyroidism. Measurement of serum total thyroxine (T4) concentration is a useful initial screening test since most hypothyroid dogs have values below the reference range. Serum free T4 concentration measured by equilibrium dialysis is a more sensitive and specific test of thyroid function than total T4 and is particularly useful in dogs with non-thyroidal illness or atypical clinical signs. Measurement of serum endogenous thyroid-stimulating hormone concentration is also helpful, but many hypothyroid dogs have normal results. The gold standard for diagnosis of hypothyroidism remains the thyroid-stimulating hormone response test. It should be used to confirm hypothyroidism when other tests do not agree with the clinical impression or if atypical signs or non-thyroidal illness exist or there has been administration of drugs known to alter thyroid function tests. Ultimately, a positive response to treatment is expected in hypothyroid dogs treated appropriately with levothyroxine.     

Evaluation of serum fructosamine concentration as an index of blood glucose control in cats with diabetes mellitus.

Fructosamine, a glycated serum protein, was evaluated as an index of glycemic control in normal and diabetic cats. Fructosamine was determined manually by use of a modification of an automated method. The within-run precision was 2.4 to 3.2%, and the day-to-day precision was 2.7 to 3.1%. Fructosamine was found to be stable in serum samples stored for 1 week at 4 C and for 2 weeks at -20 C. The reference range for serum fructosamine concentration in 31 clinically normal colony cats was 2.19 to 3.47 mmol/L (mean, 2.83 +/- 0.32 mmol/L). In 27 samples from 16 cats with poorly controlled diabetes mellitus, the range for fructosamine concentration was 3.04 to 8.83 mmol/L (mean, 5.93 +/- 1.35 mmol/L). Fructosamine concentration was directly and highly correlated to blood glucose concentration. Fructosamine concentration also remained high in consort with increased blood glucose concentration in cats with poorly controlled diabetes mellitus over extended periods. It is concluded that measurement of serum fructosamine concentration can be a valuable adjunct to blood glucose monitoring to evaluate glycemic control in diabetic cats. The question of whether fructosamine can replace glucose for monitoring control of diabetes mellitus requires further study.     

Studies on the functional relationship between thyroid, adrenal and gonadal hormones

In order to clarify the functional relationship between thyroid, adrenal and gonadal hormones, hypothyroidism was induced by administration of thiuoracil in adult male and female rats, and the effects of hypothyroidism on the adrenal and the gonadal axes were investigated in the present study. 1. The functional relationship between thyroid and adrenal hormones: Adrenal weights and corticosterone were lowered, whereas the secretion of ACTH, corticotrophin-releasing hormone (CRH) and arginine vasopressin (AVP) increased in hypothyroid rats compared to euthyroid rats. These results indicate that hypothyroidism causes adrenal dysfunction directly and results in hypersecretion of CRH and AVP from the hypothalamus. 2. The functional relationship between thyroid and gonadal hormones: The pituitary response to LHRH was lowered, whereas the testicular response to hCG was not changed in hypothyroid rats. Hypothyroidism suppressed copulatory behavior in male rats. These results suggest that hypothyroidism probably causes dysfunction in gonadal axis at the hypothalamic-pituitary level in male rats. In adult female rats, hypothyroidism inhibited the follicular development accompanied estradiol secretion, whereas plasma concentrations of progesterone and prolactin (PRL) increased in hypothyroid female rats. Hypothyroidism significantly increased the pituitary content of vasoactive intestinal peptide (VIP) though it did not affect dopamine synthesis. These results suggest that hypothyroidism increases pituitary content of VIP and this increased level of VIP likely affects PRL secretion in a paracrine or autocrine manner. In female rats, inhibition of gonadal function in hypothyroid rats mediated by hyperprolactinemia in addition to hypersecretion of endogenous CRH.     

Impaired local deiodination of thyroxine to triiodothyronine in dogs with symmetrical truncal alopecia

Thyroid dysfunction causes certain dermatological alterations in dogs. Insufficient delivery of thyroid hormone to the skin may originate not only from inadequate thyroid function but also from impaired local activation of thyroxine in the target organ. Thyroid parameters and deiodination were investigated in healthy dogs (group C) and in dogs with cutaneous lesions associated with hypothyroidism (group H) or with a low-T₃ syndrome (group LT). The ability of the skin to convert T₄ to T₃ was impaired in both groups H and LT but not in the controls. It is concluded that impaired local deiodination may contribute to skin problems in dogs.Abbreviations bwt body weight - DTT dithiothreitol - PBS phosphate-buffered saline (pH 7.5, 0.05 mol/L) - PTU propylthiouracyl - RIA radioimmunoassay - TRH thyrotropin-releasing hormone - TSH thyroid-stimulating hormone     

Serum total thyroxine and thyroid stimulating hormone concentrations in dogs with behavior problems

The aim of this case controlled study was to determine whether dogs with behavioral problems have evidence of abnormal thyroid function on routine screening tests for hypothyroidism. The hypothesis of the study was that thyroid function, as assessed by serum total thyroxine (TT4) and serum thyroid stimulating hormone (thyrotropin) (TSH) concentrations, is normal in most dogs with behavioral problems. Concentrations of TT4 and TSH in 39 dogs with behavior problems presenting to a veterinary behavior referral clinic (abnormal behavior group), were compared with TT4 and TSH concentrations in 39 healthy control dogs without behavior problems presenting to 5 community veterinary practices (control group). Dogs in the control group were matched for age and breed with the abnormal behavior group. Dogs with behavioral problems had higher TT4 concentrations than dogs without behavioral problems (t-test: t = 2.77, N = 39, P = 0.009), however none of the TT4 values were outside the reference range. There was no significant difference in TSH concentration between the 2 groups. Two dogs with behavior problems and 1 dog without behavior problems had results suggestive of hypothyroidism. All other dogs were considered to be euthyroid. There was no evidence to support a diagnosis of hypothyroidism in the majority of dogs with behavior problems in this study. The higher concentration of TT4 in dogs with behavior problems suggests, however, that alteration in thyroid hormone production or metabolism may occur in some dogs with behavior problems. Further studies that include additional indicators of thyroid status such as serum total triiodothyronine, serum, free thyroxine, and anti-thyroid antibody concentrations are necessary to further evaluate the significance of this finding.     

Hypothyroidism in the foal

Hypothyroidism in the foal occurs as two entities because of the separate actions of thyroid hormones in regulation of metabolic rate and in cell differentiation. The hypometabolic state which results in inadequate thermogenesis and lethargy, occurs concurrently with a period when thyroid hormone secretion is inadequate. Also the severity of the concurrent symptoms is related to the degree of hormone inadequacy as measured by plasma concentrations of free T4 and T3. By contrast, the developmental lesions caused by hypothyroidism are often observed during periods when plasma thyroid hormone concentrations are normal. This is because during the development of most tissues there is a period during which deprivation of thyroid hormones leads to developmental defects which may first appear weeks or months later, by which time thyroid hormone levels may have returned to normal. In the foal the critical period for some developmental processes, eg, myelination, is before birth so it is difficult to confirm a pre-natal hypothyroid state as the cause of neonatal neuromuscular incompetence. Post natal developmental lesions of the epiphyses or ossification centres, for example, may also manifest themselves some weeks subsequent to the period during which hypothyroidism existed. Because confirmation of diagnosis using plasma hormone measurements is very difficult in the foal, and because the symptoms of hypothyroidism are not specific, the incidence of confirmed hypothyroidism in foals is low. However there is suggestive evidence that where awareness of the condition exists it is diagnosed frequently. The aetiology is obscure although diet has been implicated.(ABSTRACT TRUNCATED AT 250 WORDS)     

Thyroid-stimulating hormone in adult euthyroid and hypothyroid horses

The purpose of this study was to validate a thyroid-stimulating hormone (TSH) assay in a model of equine hypothyroidism. Thyrotropin-releasing hormone (TRH) stimulation tests were performed in 12 healthy adult mares and geldings, aged 4 to greater than 20 years. before and during administration of the antithyroid drug propylthiouracil (PTU) for 6 weeks. Serum concentrations of equine TSH, total and free thyroxine (T4), and total and free triiodothyronine (T3) were measured. Before PTU administration, mean +/- standard deviation baseline concentrations of TSH were 0.40 +/- 0.29 ng/mL. TSH increased in response to TRH, reaching a peak concentration of 0.78 +/- 0.28 ng/mL at 45 minutes. Total and free T4 increased from 12.9 +/- 5.6 nmol/L and 12.2 +/- 3.5 pmol/L to 36.8 +/- 11.4 nmol/L and 23.1 +/- 5.9 pmol/L, respectively, peaking at 4-6 hours. Total and free T3 increased from 0.99 +/- 0.51 nmol/L and 2.07 +/- 1.14 pmol/L to 2.23 +/- 0.60 nmol/l and 5.78 +/- 1.94 pmol/L, respectively, peaking at 2-4 hours. Weekly measurements of baseline TSH and thyroid hormones during PTU administration showed that total and free T, concentrations fell abruptly and remained low throughout PTU administration. Total and free T4 concentrations did not decrease dramatically until weeks 5 and 4 of PTU administration, respectively. A steady increase in TSH concentration occurred throughout PTU administration, with TSH becoming markedly increased by weeks 5 and 6 (1.46 +/- 0.94 ng/mL at 6 weeks). During weeks 5 and 6 of PTU administration, TSH response to TRH was exaggerated, and thyroid hormone response was blunted. Results of this study show that measurement of equine TSH in conjunction with thyroid hormone measurement differentiated normal and hypothyroid horses in this model of equine hypothyroidism.