[Treatment of atresia ani type I by balloon dilatation in 5 kittens and one puppy]

Atresia ani is the most common anorectal anomaly in small animals. In the present study, an anal stricture (atresia ani type I) in five 3 to 8 weeks old kittens and one 4 month old puppy was treated by balloon dilation. In 4 kittens and the puppy the stricture was eliminated permanently and without complications by a single intervention. Only the smallest kitten with the most severe stenosis developed a rectal fistula as a complication of repeated balloon dilation, which necessitated surgical correction. Balloon dilation proved to be an efficient therapeutic method for anal atresia type I, and can be recommended as the treatment of choice.

Effects of high carbohydrate and high fat diet on plasma metabolite levels and on i.v. glucose tolerance test in intact and neutered male cats

To elucidate the impact of dietary influence on carbohydrate and lipid metabolism and on the development of diabetes mellitus in the carnivorous cat, a 3 weeks feeding trial was carried out on six sexually intact and six neutered adult male cats. The effects of two isonitrogenic diets, differing in carbohydrate and fat content, were investigated on plasma metabolite levels in a 24-h blood sampling trial. Plasma leptin concentrations were also determined at the beginning and at the end of the 24-h trial. Glucose and insulin response was measured in an i.v. glucose tolerance test. A 5 days long digestion trial was also performed, which revealed a high digestion capacity of both fat and carbohydrates in cats. The high fat diet induced a significant rise in the plasma triglyceride, FFA, beta-hydroxybutyrate and cholesterol concentration, while the elevation in the glucose level did not reach significance. In the glucose tolerance test no significant difference was found between the neutered and intact cats. However, independently of the sexual state, the cats on the high fat diet showed a slightly elongated glucose clearance and reduced acute insulin response to glucose administration. This is indicative of diminished pancreatic insulin secretion and/or beta-cell responsiveness to glucose. The results of this preliminary study may be the impetus for a long-term study to find out whether it is rather the fat rich ration than carbohydrate rich diet that is expected to impair glucose tolerance and thus might contribute to the development of diabetes mellitus in cats. Whether the alteration in glucose metabolism is due to altered leptin levels remains to be determined.

[Possibilities of minimal invasive cardiac catheter interventions in the dog]

The therapeutic possibilities in veterinary cardiology have developed rapidly in the past few years. Whereas until recently cardiac intervention in dogs could only be performed by thoracotomy, new minimally invasive techniques are adopted. Procedures like balloondilatation of pulmonic stenosis, coil embolisation of patent ductus arteriosus, pacemaker implantation in symptomatic bradyarrhyhtmia, and palliative balloon pericardiotomy are becoming more and more established. These alternative interventional methods are attractive, because no postsurgical pain and no complications potentially associated with thoracotomy ensue. The knowledge of such new treatment modalities and particularly the indications for an intervention are prerequisites to apply them optimally and broadly.

Balloon dilation for the treatment of chronic recurrent nasopharyngeal stenosis in a cat

Balloon dilation was used for the treatment of a recurrent nasopharyngeal stenosis in a cat with chronic stertorous breathing. The procedure was performed on three occasions at intervals of three and four months using a 15 mm valvuloplasty balloon dilation catheter. After the first dilation, clinical signs reappeared within two weeks due to re-stenosis. After the second dilation, all signs of nasopharyngeal disease disappeared, and did not recur. Endoscopic re-evaluation after four months revealed a markedly enlarged nasopharyngeal opening with some degree of stenosis, and a third balloon dilation was performed. Five months later, the cat remained without clinical signs, although some recurrence of the stenosis was visible endoscopically. Complications occurred after the first dilation, and included mild conchal necrosis and transient mucopurulent discharge. Balloon dilation is a minimally invasive technique and can be a successful procedure for treating nasopharyngeal stenosis in cats.

[Pseudohypoadrenocorticism in two Siberian huskies with gastrointestinal parasitoses]

Two Siberian Huskies were presented because of anorexia, chronic diarrhoea, polydipsia and polyuria. The most significant clinical finding was a severe dehydration. Laboratory results showed severe electrolyte disturbances with sodium: potassium ratios of 13.2 and 15.4, respectively. Hypoadrenocorticism could be excluded in both dogs with an ACTH stimulation test. The plasma aldosterone concentrations before and after stimulation were very high, which might be due to a stimulation by the electrolyte disturbances. The final diagnosis was an infection with the whipworm Trichuris vulpis and secondary pseudohypoadrenocorticism. A life-threatening dehydration syndrome with hyponatremia, hyperkalemia and metabolic acidosis due to intestinal parasitism has been reported in earlier studies. Up till now sodium: potassium ratios less than 14, however, have only been seen in animals with Morbus Addison. The severe hyperkalemia in these dogs might be due to a particular sensitivity in this breed.

[Life threatening metabolic disorders after application of a sodium phosphate containing enema in the dog and cat]

Application of a sodium phosphate containing enema caused life-threatening metabolic disorders in a Dachshund and two cats. Clinical signs were characterised by dehydration and various neurological deficits including seizures. Most striking laboratory abnormalities were hypernatremia, hypocalcemia, hyperphosphatemia, and polycythemia. Despite intensive treatment the dog died, whereas the cats recovered completely. In face of possible severe and potentially fatal metabolic abnormalities sodium phosphate enemas, such as Practo-Clyss, should be used with caution or not at all in cats and small dogs.

Thyrotropin-releasing hormone stimulation test to assess thyroid function in severely sick cats

Basal serum thyroxine (T4) concentration and the thyrotropin-releasing hormone (TRH) stimulation test were used to assess thyroid function in 36 critically ill cats examined between July 1996 and October 1998. Of the 36 cats. hyperthyroidism (as underlying or complicating disease) was suspected in 22 based on clinical signs, palpable thyroid nodules, and abnormal thyroid gland histology (study group). Hyperthyroidism was not suspected in the remaining 14 cats, which served as the control group. Based on serum T4 concentrations, suppression of thyroid function was documented in 14 (64%) cats of the study group and in 10 (71%) cats of the control group. The TRH stimulation test revealed an increase in serum T4 of less than 50% of the baseline concentration in 18 (82%) cats of the study group, and in 6 (43%) cats of the control group. In conclusion, based on the results of serum T4 determinations and the TRH stimulation tests, it was not possible to differentiate between cats with clinical and histologic evidence of thyroid dysfunction (hyperthyroidism) and cats with severe nonthyroidal illnesses.

Ultrasonography of the parathyroid glands as an aid in differentiation of acute and chronic renal failure in dogs

OBJECTIVE

To evaluate whether determination of parathyroid gland size by use of ultrasonography is helpful in differentiating acute renal failure (ARF) from chronic renal failure (CRF) in dogs.

DESIGN

Prospective study.

ANIMALS

20 dogs with renal failure in which serum creatinine concentration was at least 5 times the upper reference limit. Seven dogs had ARF, and 13 dogs had CRF. Twenty-three healthy dogs were used as controls.

PROCEDURE

Dogs were positioned in dorsal recumbency for ultrasonographic examination of the ventral portion of the neck, A 10-MHz linear-array high-resolution transducer was used. The size of the parathyroid gland was determined by measuring the maximal length of the gland on the screen when it was imaged in longitudinal section. For comparison among groups, the longest linear dimension of any of the parathyroid glands of each dog was used.

RESULTS

Size of the parathyroid glands in the control dogs varied from 2.0 to 4.6 mm (median, 3.3 mm). In the dogs with ARF, gland size ranged from 2.4 to 4.0 mm (median, 2.7), which was not significantly different from controls. In dogs with CRF, the glands were more distinctly demarcated from the surrounding thyroid tissue, than those of controls and dogs with ARF. Sizes ranged from 3.9 to 8.1 mm (median, 5.7 mm), which was significantly larger, compared with controls and dogs with ARF.

CONCLUSIONS AND CLINICAL RELEVANCE

In dogs with severe azotemia, ultrasonographic examination of the parathyroid glands was helpful in differentiating ARF from CRF Size of the parathyroid glands appeared to be related to body weight.

Serum fructosamine concentration in cats with overt hyperthyroidism

OBJECTIVE

To determine the effect of hyperthyroidism on serum fructosamine concentration in cats.

DESIGN

Cohort study.

ANIMALS

22 cats with overt hyperthyroidism.

PROCEDURE

Hyperthyroidism was diagnosed on the basis of clinical signs, detection of a palpable thyroid gland, and high total serum thyroxine (T4) concentrations. Hyperthyroid cats with abnormal serum albumin, total protein, and glucose concentrations were excluded from the study. Samples for determination of serum fructosamine concentration were obtained prior to initiating treatment. Results were compared with fructosamine concentrations in healthy cats, cats in which diabetes had recently been diagnosed, and cats with hypoproteinemia. In 6 cats, follow-up measurements were obtained 2 and 6 weeks after initiating treatment with carbimazole.

RESULTS

Serum fructosamine concentrations ranged from 154 to 267 mumol/L (median, 198 mumol/L) and were significantly lower than values in healthy cats. Eleven (50%) of the hyperthyroid cats had serum fructosamine concentrations less than the reference range. Serum fructosamine concentrations in hyperthyroid, normoproteinemic cats did not differ from values in hypoproteinemic cats. During treatment, an increase in serum fructosamine concentration was detected.

CONCLUSIONS AND CLINICAL RELEVANCE

In hyperthyroid cats, concentration of serum fructosamine may be low because of accelerated protein turnover, independent of blood glucose concentration. Serum fructosamine concentrations should not be evaluated in cats with overt hyperthyroidism and diabetes mellitus. Additionally, concentration of serum fructosamine in hyperthyroid cats should not be used to differentiate between diabetes mellitus and transitory stress-related hyperglycemia.

Nutritional secondary hyperparathyroidism in six cats

Nutritional secondary hyperparathyroidism (NSH) was diagnosed in six cats during a three-year period, based on clinical, radiographic and laboratory findings. Clinical signs were attributable to severe osteopenia (n = 5) and hypocalcaemia (n = 4), which had resulted in spontaneous fractures of long bones, scapulae, pelvis, nasal bones, or spine, and in excitation, muscle twitching or seizures, respectively. Serum parathormone levels were markedly elevated, and 1,25(OH)2-vitamin D3 mildly elevated, whereas 25(OH)-vitamin D3 was mildly decreased compared to age-matched healthy cats. Treatment was limited to short-term parenteral calcium gluconate injections, as clinically indicated, a balanced diet and cage rest, which resulted in quick clinical recovery in four cases. The remaining two cats had to be euthanased because of progressive neurological deficits secondary to spinal fractures. At the time of writing, a multitude of commercial balanced diets is widely available and diseases secondary to dietary deficiencies have become rare. Nevertheless, NSH is still an important clinical entity, and should be considered in growing cats presenting with spontaneous fractures or seizures.