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Created page with "{{review}} =Introduction= 200px|thumb|right|'''Biopsy of this swelling revealed renal gout''' © RVC Gout is a metabolic disease where there is a '''precipit..."
{{review}}

=Introduction=
[[Image:Bump2.jpg|200px|thumb|right|'''Biopsy of this swelling revealed renal gout''' © RVC]]
Gout is a metabolic disease where there is a '''precipitation''' of '''urate crystals''' in tissue. There are two types of gout in animals.
*In '''primary gout''' there is an overproduction of [[Uric acid|uric acid]] related to an innate metabolic problem.
*In '''secondary gout''', acquired disease interferes with the [[Uric acid|uric acid]] metabolism. Terrestrial reptiles are predisposed to secondary gout since nitrogenous waste is excreted as [[Uric acid|uric acid]].

'''For more information on excretion, see''' [[Lizard and Snake Excretion]].


=Snakes=
In snakes, kidney disease often leads to the development of a '''visceral gout''' where '''uric acid crystals''' (tophi) are deposited in subcutaneous and internal tissues.

==Examination==
History may show '''poor husbandry''' including limited access to water. Snakes often present as anorexic and lethargic. Often if kidney disease is involved there is a palpable lump in the caudal third.

For a differential diagnosis list of other causes of lumps in the body, see [[Snake Lumps and Bumps]].
[[Image:Necropsy_copy.jpg|200px|thumb|right|'''Tophi in renal tissue''' - © RVC]]

==Diagnosis==
The diagnosis of gout may be suspected on history and physical examination. [[Lizard and Snake Biochemistry|Biochemistry]] may indicate a [[Lizard_and_Snake_Biochemistry#Hyperuricaemia|hyperuricaemia]]. Sometimes [[Lizard and Snake Imaging|radiography]] is useful if calcium is deposited with the urate crystals. Biopsy of any lumps may be useful. A definite diagnosis is the demonstration of '''tophi''' in diseased tissue.

'''For more information on physical examinations, see''' [[Snake Physical Examination]].

'''For more information on biopsy collection, see''' [[Lizard and Snake Specimen Collection and Evaluation|Specimen Collection and Evaluation]].
[[Image:Renal_gout_python_regius.jpg|200px|thumb|right|'''Tophi in diseased tissue''' © RVC]]

==Therapy==
'''Supportive treatment''' especially aimed at rehydration may be useful but gout carries a poor prognosis. Previously allopurinol (a xanthine oxidase inhibitor that decreases formation of uric acid) has been recommended as a treatment of hyperuricaemia in reptiles and birds but in fact appears to be of little use. Other drugs such as uricases (enzymes involved in the degradation of uric acid to allantoin) may be more useful.

'''For more information, see''' [[Snake Supportive Care]].

==Prevention==
Any bouts of '''dehydration''' will predispose to the development of gout so good husbandry is important in prevention. Vets should ensure adequate hydration of reptiles prior to any drug therapy but especially when using nephrotoxic drugs.

'''For more information on good husbandry practices, see''' [[:Category: Snake Husbandry| Snake Husbandry]].


=Other Reptiles=
Gout is a common condition in various species of '''captive reptiles'''. High-protein or poor quality protein diets, [[Dehydration|dehydration]] and [[Lizard and Snake Renal Disease|renal disease]] are all thought to contribute to its development - as they increase levels of uric acid. Urate crystals can precipitate in the '''joints, kidneys, and other internal organs'''.

==Examination==
There may be a history of poor husbandry, including limited access to water and the feeding of a low quality protein diet. On clinical exam, there may be '''swelling of the joints''' and the animal will appear''' painful and reluctant to move'''.

==Diagnosis==
The diagnosis of gout may be suspected on history and physical examination and [[Lizard and Snake Biochemistry|Biochemistry]] may show a [[Lizard_and_Snake_Biochemistry#Hyperuricaemia|hyperuricaemia]]. Sometimes [[Lizard and Snake Imaging|radiography]] is useful if calcium is deposited with the urate crystals. Biopsy of any lumps may be useful.

'''For more information on physical examinations, see''' [[Lizard Physical Examination]].

'''For more information on biopsy collection, see''' [[Lizard and Snake Specimen Collection and Evaluation|Specimen Collection and Evaluation]].

==Therapy==
The '''hydration''' of the reptile should be improved by providing ample water and feeding moisture-laden food such as soft fruits.
If the reptile is '''omnivorous''', levels of animal protein should be decreased. If the reptile is '''carnivorous''', instead of decreasing levels of proetin in the diet, you should ensure that the protein fed is of a high quality.

Additionally, allopurinol can be given orally on a daily basis. It decreases the quantity of urate salts produced by the liver, but does not help to remove the crystals that have already precipitated around the joints and organs, so is often of little use.

'''Pain relief''' can be provided using [[NSAIDs]], but gastrointestinal side effects may be seen.

==Prevention==
'''[[Lizard Husbandry|Good husbandry]]''' is the best way to prevent the development of gout. Ample water, and the correct amount of high quality protein (variable according to species) should be provided for the reptile. Before the administration of any drug therapy (particularly nephrotoxic drugs) the hydration status of the animal should be checked.

{{Learning
|flashcards = [[Reptiles and Amphibians Q&A 19]]
}}

=Literature Search=
[[File:CABI logo.jpg|left|90px]]


Use these links to find recent scientific publications via CAB Abstracts (log in required unless accessing from a subscribing organisation).
<br><br><br>
[http://www.cabdirect.org/search.html?q=(title:(snake)+OR+ab:(snake)+OR+od:(snake))+AND+(title:(gout)+OR+title:(urate+crystals)) Snake Gout publications]

[http://www.cabi.org/cabdirect/FullTextPDF/2009/20093069421.pdf ''' Reptilian gout: clinical overview.''' Mader, D. R.; Association of Reptilian and Amphibian Veterinarians, Chester Heights, USA, Proceedings of the Association of Reptilian and Amphibian Veterinarians, 14th Annual Conference, New Orleans, Louisiana, USA, 14-18 April, 2007, 2007, pp 110-115, 4 ref. - '''Full Text Article''']

==References==
Frye, FL & Williams, DL (1995) '''Self-Assessment Colour Review - Reptiles & Amphibians''' ''Manson''

Merck & Co (2009) '''The Merck Veterinary Manual''' (Ninth Edition), ''Merial''

[[Category: To Do - Siobhan Brade]]
[[Category:To Do - Manson review]]

[[Category:Snake_Diseases]]
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