Gout pathophysiology: Difference between revisions
Undo revision 1668073 by Shivam Singla (talk) Tag: Undo |
No edit summary |
||
Line 54: | Line 54: | ||
This is the most common cause of hyperuricemia. Various factors responsible for its reduced elimination are: | This is the most common cause of hyperuricemia. Various factors responsible for its reduced elimination are: | ||
* Hereditary | *Hereditary | ||
* Compromised renal function ( Reduced GFR) | *Compromised renal function ( Reduced GFR) | ||
* On Diuretics | *On Diuretics | ||
* Alcohol intake | *Alcohol intake | ||
** The lactic acid blocks the excretion of urate from the from the renal tubules. Alcohol induces the purine metabolism in the liver and increases the formation of lactic acid and | **The lactic acid blocks the excretion of urate from the from the renal tubules. Alcohol induces the purine metabolism in the liver and increases the formation of lactic acid and | ||
** Alcohol also directly stimulates the synthesis of urate by the liver | **Alcohol also directly stimulates the synthesis of urate by the liver | ||
* Drugs like cyclosporine that are toxic to the renal tubules leads to the decreased elimination of uric acid and ultimately resulting in the urate retention | *Drugs like cyclosporine that are toxic to the renal tubules leads to the decreased elimination of uric acid and ultimately resulting in the urate retention. | ||
Line 79: | Line 71: | ||
|[[Image:Gout 0001.jpg|thumb|Kidney: Uric Acid Deposition: Gross, an excellent example of gouty nephropathy with deposits and excavation in pyramids]] | |[[Image:Gout 0001.jpg|thumb|Kidney: Uric Acid Deposition: Gross, an excellent example of gouty nephropathy with deposits and excavation in pyramids]] | ||
|[[Image:Gout 0002.jpg|thumb|Kidney: Papillary Necrosis: Gross, yellow foci in pyramids, a gout kidney]] | |[[Image:Gout 0002.jpg|thumb|Kidney: Papillary Necrosis: Gross, yellow foci in pyramids, a gout kidney]] | ||
| | | | ||
|} | |} | ||
{| align="center" | {| align="center" | ||
|- valign="top" | |- valign="top" | ||
| | | | ||
| | | | ||
| | | | ||
|} | |} | ||
{| align="center" | {| align="center" | ||
|- valign="top" | |- valign="top" | ||
| | | | ||
| | | | ||
| | | | ||
|} | |} | ||
{| align="center" | {| align="center" | ||
|- valign="top" | |- valign="top" | ||
| | | | ||
| | | | ||
| | | | ||
|} | |} | ||
{| align="center" | {| align="center" | ||
|- valign="top" | |- valign="top" | ||
| | | | ||
| | | | ||
| | | | ||
|} | |} | ||
{| align="center" | {| align="center" | ||
|- valign="top" | |- valign="top" | ||
| | | | ||
| | | | ||
|} | |} | ||
Line 122: | Line 114: | ||
|[[Image:Gout (no birefringence).jpg|thumb|Gout (Needles, no birefringence, monosodium urate)]] | |[[Image:Gout (no birefringence).jpg|thumb|Gout (Needles, no birefringence, monosodium urate)]] | ||
|[[Image:Gout 0003.jpg|thumb|Skin: Tophus: Micro med mag H&E uric acid deposits with giant cells. Easily recognizable as gout or uric acid tophus]] | |[[Image:Gout 0003.jpg|thumb|Skin: Tophus: Micro med mag H&E uric acid deposits with giant cells. Easily recognizable as gout or uric acid tophus]] | ||
| | | | ||
| | | | ||
|} | |} | ||
{| align="center" | {| align="center" | ||
|- valign="top" | |- valign="top" | ||
| | | | ||
| | | | ||
| | | | ||
| | | | ||
|} | |} | ||
{| align="center" | {| align="center" | ||
|- valign="top" | |- valign="top" | ||
| | | | ||
| | | | ||
| | | | ||
| | | | ||
|} | |} | ||
Revision as of 17:45, 5 October 2020
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Shivam Singla, M.D.[2]
Overview
Pathophysiology
The pathophysiology of Gout mainly relates to hyperuricemia. Greater is the degree of hyperuricemia greater is the likelihood of developing Gout.
There are numerous reasons that can lead to the development of increase in level of uric acids:
- Enhanced or increased purine uptake.
- Decreased excretion of uric acid
- Increased production of uric acid
- Etiology in lot of cases with rise in uric acid levels is still unknown.
Increased intake
The increased uptake is mainly related to
- Increases intake of purine rich food substances by the patient such as
- Asparagus, met broths, mushrooms, liver, kidney, sweetbreads, .
- The increased intake of all of these substances can increase the risk of accumulation of more and more purines ultimately resulting in the excess of uric acid.
- Beer is also particularly rich in guanosine which is a purine nucleotide.
Increased production
The increased production is mainly related to conditions associated with
- Increase in turn over of of cells like in various hematological conditions such as Hemolytic anemia, leukemia and lymphoma.
- Conditions associated with increase rate of cell proliferation and cell death.
- Cytotoxic therapy
- Radiation
- Psoriasis
- Obesity - As the urate production is directly proportional to the body surface area
- Hereditary conditions
- Enzyme abnormalities
- Overactivity of Phosphoribosyl transferase
- Deficiency of HGPRT
- Absence of HGPRT ( Lesch-nyhan syndrome)
Decreased/Reduced renal excretion
This is the most common cause of hyperuricemia. Various factors responsible for its reduced elimination are:
- Hereditary
- Compromised renal function ( Reduced GFR)
- On Diuretics
- Alcohol intake
- The lactic acid blocks the excretion of urate from the from the renal tubules. Alcohol induces the purine metabolism in the liver and increases the formation of lactic acid and
- Alcohol also directly stimulates the synthesis of urate by the liver
- Drugs like cyclosporine that are toxic to the renal tubules leads to the decreased elimination of uric acid and ultimately resulting in the urate retention.
Gross Pathology
Microscopic Pathology
Sources
Copyleft images obtained courtesy of Charlie Goldberg, M.D., UCSD School of Medicine and VA Medical Center, San Diego, CA) Images courtesy of Professor Peter Anderson DVM PhD and published with permission © PEIR, University of Alabama at Birmingham, Department of Pathology