Gout is a metabolic disease characterized by deposition of urates on the surfaces of various internal organs, or various joints

1. Gout
• Gout is a metabolic disease characterized by deposition of urates on the
surfaces of various internal organs, or various joints
• Both in broiler and layer chicks, gout can be seen from 4th day onward and can
be a serious problem between 2nd and 3rd week
• Birds usually die from kidney failure

2. Types of gout
• Visceral gout – deposition of uric acid crystals in visceral organs
like kidney, liver, heart and gut. It is the acute and more common
form of gout reported in poultry. It causes huge mortality in
poultry ranging from 15-35 per cent. It is observed in young
poultry.
• Articular gout – deposition of uric acid crystals in joints,
ligaments and tendon sheath. It is chronic form of gout and has
some genetic predisposition. It is rarely seen in poultry

3. pathogenesis
• Uric acid is the end product of purine and protein metabolism in
poultry. Uric acid is formed in the liver and excreted by kidneys.
• Birds are uricotelic, lack the enzyme uricase and this along with the
process of water conservation, allows them to excrete urine in the
form of semi-solid uric acid in the faeces.
• Disruption in the metabolic process of excretion of uric acid leads to
gout.
• So,gout can arise either due to production of uric acid over the
capacity of kidneys to excrete it, or due to compromised kidney
function failing to excrete the produced uric acid

4. Postmortem Findings
I. Presence of white chalky deposits on the surfaces of heart, liver,
kidneys, proventriculus, and lungs. These deposits are seen as white
chalky coating

5. 2. The chalky deposits first begin on the heart and
then spread
3. Kidneys are swollen, congested,
and typically gouty (greyish white in colour) .
4. One or both ureters may be distended with white material.
5.In the articular gout, when joints are opened,
the tissue surrounding the joints is white due to urate
deposition

6. Diagnosis
• Joint fluid test. Your doctor may use a needle to draw fluid from your affected
joint. Urate crystals may be visible when the fluid is examined under a microscope
• Blood test. Your doctor may recommend a blood test to measure the levels of uric
acid and creatinine in your blood. Blood test results can be misleading, though.
Some people have high uric acid levels, but never experience gout. And some
people have signs and symptoms of gout, but don't have unusual levels of uric acid
in their blood.
• X-ray imaging. Joint X-rays can be helpful to rule out other causes of joint
inflammation.
• Ultrasound. Musculoskeletal ultrasound can detect urate crystals in a joint or in a
tophus

7. Differential diagnosis
 Pseudogout (calcium pyrophosphate deposition disease)
• The definitive diagnosis is finding calcium pyrophosphate crystals in the
synovial fluid. These are rhomboid-shaped, weakly positively birefringent
crystals.
• Chondrocalcinosis (radiographic calcification of cartilage in certain joints) is
usually present.
 Septic arthritis
• Synovial fluid microscopy and culture may be Gram positive and show
growth.
• Blood cultures may grow the causal bacteria
 Trauma
• Synovial fluid is usually bloody and has no monosodium urate crystals.
 Rheumatoid arthritis (RA)
• Synovial fluid is inflammatory (WBC count >2000/mm^3), but no
monosodium urate crystals are found
 Reactive arthritis
• X-rays may show soft-tissue swelling