suspected dwarfism in a kitten

Re: suspected dwarfism in a kitten

salome2001 — Tue, 24 Aug 2010 12:32:50 GMT

While common in humans, the frequency and importance of CH in kittens remain unknown, but may be underreported and misdiagnosed as idiopathic megacolon and other skeletal anomalies. Once megacolon, short stature, and mental dullness are recognized as clinical signs of CH, a diagnosis of hypothyroidism is easily made in a kitten based on a serum T₄ level at or below the normal adult range. A full thyroid profile including serum TSH concentrations can further classify the disease: TSH is expected to be high in CH not originating in the hypothalamus or pituitary gland. Although the assay is not validated for the cat, the assay for canine TSH has recently been demonstrated to detect feline TSH (http://www.animalhealth.msu.edu/FAQ/Endocrinology/Thyroid_Feline.php#04). The normal range of thyroid hormone levels in kittens is not well established. In most mammals including children, the normal range is slightly higher than adults. However in 1 study, kittens approached the upper end of the normal adult range but did not go above the range as seen in other species.^e

Re: suspected dwarfism in a kitten

Michael Woodhouse — Mon, 23 Aug 2010 21:20:47 GMT

[quote user="salome2001"]Owner has opted to check IGF-1 to see if primary or secondary hypothyroid as clinically it sounds like it fits the diagnosis- the difference will be in prognosis really. [/quote]

That is IF it truly is hypothyroid.

Re: suspected dwarfism in a kitten

salome2001 — Mon, 23 Aug 2010 12:57:00 GMT

an interim follow-up: on questioning the owner does think this kitten is dull compared to littermate and also ataxic/ less mobile (apparently boy companion is a true littermate, so we have a true comparison, including dentition which is normal in boy).

Reviewing human literature on PubMed shows that you can get quite excessive CK increases with a hypothyroid myopathy (in addition to growing increases CK- this increase in this kitten was reallly dramatic - 10x upper "normal" limit with no history of trauma - and my blood sampling technique is not that bad!)

Owner has opted to check IGF-1 to see if primary or secondary hypothyroid as clinically it sounds like it fits the diagnosis- the difference will be in prognosis really.

Re: suspected dwarfism in a kitten

Jillian Hall — Wed, 18 Aug 2010 22:59:50 GMT

Have you seen the forum from a few months ago under "Stunted kitten". That kitten was clinically 100% apart from his small stature, Ended up plumping for (provisional) hereditary cobalamin malabsorption. Have you checked cobalamin levels - the lab could probably run it from the T4 sample if that was sent off.

I think high CK can be normal in kittens

Re: suspected dwarfism in a kitten

sophia guymer — Wed, 18 Aug 2010 19:19:18 GMT

[quote user="salome2001"] what (if any) relevance does the increased CK have?[/quote]

I am quite happily corrected if wrong, but I seem to remember that an increase in CK is normal in growing animals

Re: suspected dwarfism in a kitten

Evelyn Barbour-Hill — Tue, 17 Aug 2010 22:53:03 GMT

If it truly is six months old it should not still have deciduous dentition.

Re: suspected dwarfism in a kitten

Utlendigur — Tue, 17 Aug 2010 22:14:27 GMT

Just wondering about the comment that the kitten has a rounded head. A collegue saw a kitten recently that was tiny for its age and had a strange-looking rounded head. Also a bit bow legged, wide interdental spaces and other odd things. Also belonged to owners with no money - so no work up at all - but someone at Bristol (I think - sorry for vagueness, it wasn't my case) suspected it might have a storage disease from the photos. Does your kitten look normal apart from the size?

Re: suspected dwarfism in a kitten

Michael Woodhouse — Tue, 17 Aug 2010 20:16:35 GMT

None-thyroidal illness causing reduced T4?

If the cat's normal why all the tests? Just spay it and see what happens?