Feline congenital hypothyroidism: a case report

We report a two-month-old male cat weighing 630 grams with congenital hypothyroidism. The main complaints were difficulty defecating for more than three days and prostration. Physical examination revealed a broad, flat face, a short neck, enlarged submandibular lymph nodes, chemosis, mild bilateral mucopurulent ocular discharge, seborrheic coat, with gingival thickening around the upper and lower deciduous incisor teeth with partial eruption. The abdomen was distended due to constipation and right unilateral cryptorchidism. Based on this, feline congenital hypothyroidism was suspected. Hormonal tests (free T4 by equilibrium dialysis of 0.06 ng/dl, total T4 of 0.1 ng/ml and TSH of 4.7 ng/ml) confirmed this. Treatment was started with levothyroxine sodium (5-32.2 µg/kg/day). After 120 days of treatment, there was clinical stabilization. Then the patient underwent orchiectomy of the left and of the right ectopic testicles, and at 380 days of treatment, the thyroid scintigraphy showed intense uptake of the radiopharmaceutical by both thyroid lobes and a significant increase in volume. Clinical evaluation showed weight gain (2.6 kilograms during treatment), improvement in the shape of the skull, and a notable increase in body size. At 17 months of age, hormone values were within the reference limits after administration of levothyroxine sodium (32.2µg/kg/day).

Medical Management of Dental Abnormalities Related to Congenital Hypothyroidism in a Cat

A 5-month-old intact male domestic shorthair cat presenting for routine vaccinations was diagnosed with congenital hypothyroidism. His primary presenting symptom was incomplete dentition with delayed dental eruption. Congenital hypothyroidism was confirmed by baseline thyroxine (T4), free T4, and thyroid-stimulating hormone testing. The cat was treated with oral thyroid hormone supplementation and 16 weeks after initiation of therapy the cat was clinically normal with age-appropriate dentition. No surgical intervention was necessary to achieve normal dental eruption.

Evaluation of Weight Gain, Clinicopathological and Radiographic Changes after Early Diagnosis and Treatment of Congenital Hypothyroidism in Cats

Congenital hypothyroidism is uncommon in cats. This case report describes weight gain, clinicopathological and radiographic changes after early diagnosis and treatment of congenital hypothyroidism in three British shorthair cats’ siblings. Data were assessed at 53 (diagnosis), 83, 185 and 365 days of age. Correlations between serum insulin-like growth factor-1 (IGF-1) and body weight, levothyroxine dose, total thyroxine, and thyroid-stimulating hormone concentrations were evaluated. The body weights of the congenital hypothyroid kittens were compared with those of their two healthy siblings and British shorthair kittens of the same age. At diagnosis, the congenital hypothyroid kittens showed a significantly lower body weight compared to the healthy siblings (p = 0.03). After diagnosis, oral levothyroxine supplementation was started. The difference in body weight was no longer observed after one month of treatment. The clinical signs, clinicopathological and radiographic abnormalities ameliorated after one month of treatment. IGF-1 concentration was significantly positively correlated with body weight (rs = 0.80, p < 0.002). In conclusion, resolution of the clinical signs, achieving a consistent within-breed weight, and improvement of the clinicopathological and radiographic parameters demonstrated the importance of the early diagnosis and treatment of feline congenital hypothyroidism.

Cluster of cases of congenital feline goitrous hypothyroidism in a single hospital

OBJECTIVES

To describe the clinicopathological findings and outcomes of cases of feline congenital hypothyroidism diagnosed in a single veterinary hospital in Santiago, Chile.

MATERIALS AND METHODS

Medical records were searched for cases of congenital hypothyroidism over an 18-month period. Inclusion criteria were a diagnosis of congenital hypothyroidism based on consistent historical and clinical findings, a low or low-normal serum total T4 and elevated serum canine TSH (cTSH).

RESULTS

Six unrelated cats ranging in age from 4 to 19 months met the inclusion criteria. The most common historical signs were small stature and lethargy. All cats had disproportionate dwarfism, delayed tooth eruption, retained deciduous teeth, bilateral palpable goitres and low rectal temperatures. Other findings were bradycardia, obesity, poor hair coat and focal alopecia on the ventral aspects of the elbows and hocks. In all cases, cTSH was markedly elevated. Sequential changes noted after the initiation of therapy included normal T4 after 6 weeks, improved hair coat and increased physical activity by 8 weeks, normal cTSH by 10 weeks and normal physical appearance and dentition after 4 months. Goitres shrank markedly but remained palpable. Hypothyroidism was well managed clinically in all cases 2 years after diagnosis except for one cat that died of unrelated causes.

CLINICAL SIGNIFICANCE

This is the first report to describe a cluster of congenital hypothyroidism cases in non-related cats that were presented over a short period of time. Growth defects resolve with treatment, even in cats diagnosed after puberty. Larger, prospective multi-centre studies are warranted to determine the incidence of congenital hypothyroidism in cats.

A 10-year prevalence of congenital hypothyroidism in Khorramabad (Urban Western Iran)

Background

Congenital hypothyroidism in infants is the cause of mental retardation in children, it can be detected in patient and treated at a relatively cheap rate, preventing patient retard. This study aimed to determine the prevalence of congenital hypothyroidism among Khorramabad children.

Methods

In the present study, we identified all patients who had received levothyroxine prescriptions during the study period (2007–2017). Using this as a congenital hypothyroidism surrogate marker, we considered the congenital hypothyroidism prevalence in children above 3 years.

Results

Of 574 patients who had received levothyroxine during the neonatal period up to 3 years, the results of one‐variable logistic regression analysis showed that the chance of temporary disease in children with small thyroid ultrasonography was 62% less, than for those without problems, and this difference was significant. The chance of temporary disease in children who had other cases was 87% less than those without problems, and this difference was statistically significant.

Conclusion

The overall prevalence of congenital hypothyroidism in young patients up to 3 years is 0.143%, these values are at least twice those of previous estimates. This proposes an elevation in autoimmune thyroid disease, which is similitude to the rising prevalence of diabetes type 1, which possibly indicates a rising incidence of autoimmunity in youth.