Spontaneous bacterial peritonitis pathophysiology: Difference between revisions

Jump to navigation Jump to search
No edit summary
m (Bot: Removing from Primary care)
 
(31 intermediate revisions by 6 users not shown)
Line 1: Line 1:
__NOTOC__
__NOTOC__
{{Spontaneous bacterial peritonitis}}
{{Spontaneous bacterial peritonitis}}
{{CMG}}; {{AE}} {{ADI}} {{SCh}}
{{CMG}}; {{AE}} {{SCh}} {{AY}}  
 
==Overview==
==Overview==
SBP is a result of culmination of the inability of the gut to contain bacteria and failure of the [[immune system]] to eradicate the organisms once they have escaped.<ref name="pmid4018735">{{cite journal| author=Runyon BA, Morrissey RL, Hoefs JC, Wyle FA| title=Opsonic activity of human ascitic fluid: a potentially important protective mechanism against spontaneous bacterial peritonitis. | journal=Hepatology | year= 1985 | volume= 5 | issue= 4 | pages= 634-7 | pmid=4018735 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=4018735  }} </ref><ref name="pmid15138202">{{cite journal| author=Runyon BA| title=Early events in spontaneous bacterial peritonitis. | journal=Gut | year= 2004 | volume= 53 | issue= 6 | pages= 782-4 | pmid=15138202 | doi= | pmc=1774068 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15138202  }} </ref><ref name="pmid15920324">{{cite journal| author=Sheer TA, Runyon BA| title=Spontaneous bacterial peritonitis. | journal=Dig Dis | year= 2005 | volume= 23 | issue= 1 | pages= 39-46 | pmid=15920324 | doi=10.1159/000084724 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15920324  }} </ref>
[[Bacterial overgrowth|Intestinal bacterial overgrowth]] in [[Cirrhosis|cirrhotic]] patients, defective intestinal barrier and defective [[Immune response|host immune response]] are the 3 determinant factors for [[Bacterial|bacterial translocation]] explaining SBP.
==Pathogenesis==
Three factors play a role in the pathogenesis of SBP:
* '''[[Bacterial overgrowth]] in [[Cirrhosis|cirrhotic patients]]:''' secondary to [[Motility|decreased intestinal motility]] and frequent use of [[Proton pump inhibitor|PPIs]] in this population of patients.


==Pathophysiology==
* '''Defective intestinal barrier:''' secretory and physical barriers (which normally prevent bacteria from moving from the [[Lumen|intestinal lumen]]) are defective in [[Cirrhosis|cirrhotic patients]] <ref name="pmid16680233">{{cite journal |vauthors=Căruntu FA, Benea L |title=Spontaneous bacterial peritonitis: pathogenesis, diagnosis, treatment |journal=J Gastrointestin Liver Dis |volume=15 |issue=1 |pages=51–6 |year=2006 |pmid=16680233 |doi= |url=}}</ref>
{| align=center
|-
|
{{familytree/start}}
{{familytree | boxstyle=background: #FFF0F5; color: #000000;| | | A01 | | A01=Patients with '''decompensated [[cirrhosis]] leading to '''[[portal Hypertension]]<ref name="pmid1505916">{{cite journal| author=Llach J, Rimola A, Navasa M, Ginès P, Salmerón JM, Ginès A et al.| title=Incidence and predictive factors of first episode of spontaneous bacterial peritonitis in cirrhosis with ascites: relevance of ascitic fluid protein concentration. | journal=Hepatology | year= 1992 | volume= 16 | issue= 3 | pages= 724-7 | pmid=1505916 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=1505916  }} </ref><ref name="pmid11211904">{{cite journal| author=Cirera I, Bauer TM, Navasa M, Vila J, Grande L, Taurá P et al.| title=Bacterial translocation of enteric organisms in patients with cirrhosis. | journal=J Hepatol | year= 2001 | volume= 34 | issue= 1 | pages= 32-7 | pmid=11211904 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=11211904  }} </ref>'''}}
{{familytree | | | |!| |}}
{{familytree | boxstyle=background: #FFF0F5; color: #000000;| | | B01 | | B01='''Intestinal hypo-motility''' and '''local pro-[[inflammatory]] phenomenon'''<ref name="pmid9794900">{{cite journal| author=Chang CS, Chen GH, Lien HC, Yeh HZ| title=Small intestine dysmotility and bacterial overgrowth in cirrhotic patients with spontaneous bacterial peritonitis. | journal=Hepatology | year= 1998 | volume= 28 | issue= 5 | pages= 1187-90 | pmid=9794900 | doi=10.1002/hep.510280504 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=9794900  }} </ref>}}
{{familytree | | | |!| |}}
{{familytree | boxstyle=background: #FFF0F5; color: #000000;| | | C01 | | C01='''Bacterial overgrowth:'''<br>
Increased intestinal permeability''' and '''decreased local and systemic [[immune system]] in [[cirrhosis]] and its relation to bacterial infections and prognosis. <ref name="pmid9794900">{{cite journal| author=Chang CS, Chen GH, Lien HC, Yeh HZ| title=Small intestine dysmotility and bacterial overgrowth in cirrhotic patients with spontaneous bacterial peritonitis. | journal=Hepatology | year= 1998 | volume= 28 | issue= 5 | pages= 1187-90 | pmid=9794900 | doi=10.1002/hep.510280504 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=9794900  }} </ref><ref name="pmid11693333">{{cite journal| author=Bauer TM, Steinbrückner B, Brinkmann FE, Ditzen AK, Schwacha H, Aponte JJ et al.| title=Small intestinal bacterial overgrowth in patients with cirrhosis: prevalence and relation with spontaneous bacterial peritonitis. | journal=Am J Gastroenterol | year= 2001 | volume= 96 | issue= 10 | pages= 2962-7 | pmid=11693333 | doi=10.1111/j.1572-0241.2001.04668.x | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=11693333</ref><ref name="pmid6693068">{{cite journal| author=Rimola A, Soto R, Bory F, Arroyo V, Piera C, Rodes J| title=Reticuloendothelial system phagocytic activity in cirrhosis and its relation to bacterial infections and prognosis. | journal=Hepatology | year= 1984 | volume= 4 | issue= 1 | pages= 53-8 | pmid=6693068 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=6693068  }} </ref>}}
{{familytree | | | |!| |}}
{{Familytree|boxstyle=background: #FFF0F5; color: #000000;width: 400px; text-align: left; font-size: 90%; padding: 0px;| | | D01 | |D01=<div style="padding: 15px;"><BIG>'''Routes of entry of pathogens into the ascitic fluid'''</BIG>
:Escape of enteric bacteria to systemic circulation through:<ref name="pmid15723320">{{cite journal| author=Wiest R, Garcia-Tsao G| title=Bacterial translocation (BT) in cirrhosis. | journal=Hepatology | year= 2005 | volume= 41 | issue= 3 | pages= 422-33 | pmid=15723320 | doi=10.1002/hep.20632 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15723320  }} </ref>
:❑ Bacterial translocation<ref name="pmid11211904">{{cite journal| author=Cirera I, Bauer TM, Navasa M, Vila J, Grande L, Taurá P et al.| title=Bacterial translocation of enteric organisms in patients with cirrhosis. | journal=J Hepatol | year= 2001 | volume= 34 | issue= 1 | pages= 32-7 | pmid=11211904 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=11211904  }} </ref>
::• Luminal bacteria within colonize mesenteric [[lymph nodes]].<ref name="pmid7890896">{{cite journal| author=Runyon BA, Squier S, Borzio M| title=Translocation of gut bacteria in rats with cirrhosis to mesenteric lymph nodes partially explains the pathogenesis of spontaneous bacterial peritonitis. | journal=J Hepatol | year= 1994 | volume= 21 | issue= 5 | pages= 792-6 | pmid=7890896 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=7890896  }} </ref>
::• Organisms from the mesenteric [[lymph nodes]] → Systemic circulation through thoracic duct lymph → percolates through the liver and weep across Glisson's capsule → Ascitic fluid.
::• Transient [[bacteremia]] → Prolonged bacteremia ( due to ↓ Reticulo endothelial system activity ) → Ascites Colonization ( due to ↓ ascitic fluid bactericidal activity ) → Spontaneous bacterial [[peritonitis]] )
:❑ Portal Vein
::• Porto-systemic shunt
::• ↓RES function in the liver
:❑ Lymphatic rupture
::• Contaminated lymph carried by lymphatics
::• Ruptured Lymphatics due to high flow and high pressure associated with [[portal hypertension]] ( '''BACTERASCITES''' )<ref name="pmid8677940">{{cite journal| author=Ho H, Zuckerman MJ, Ho TK, Guerra LG, Verghese A, Casner PR| title=Prevalence of associated infections in community-acquired spontaneous bacterial peritonitis. | journal=Am J Gastroenterol | year= 1996 | volume= 91 | issue= 4 | pages= 735-42 | pmid=8677940 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8677940  }} </ref>
:❑ Other source of organisms
::• IV catheters, skin, urinary, and respiratory tract</div>}}
{{familytree | | | |!| |}}
{{Familytree|boxstyle=background: #FFF0F5; color: #000000;width: 400px; text-align: left; font-size: 90%; padding: 0px;| | | E01 | |E01=<div style="padding: 15px;"><BIG>'''Endotoxemia''' and '''[[Cytokine]] response'''</BIG>
:❑ Endotoxemia → release of pro-inflammatory [[cytokines]] produced by [[macrophages]] and other host cells in response to bacteria in the serum and peritoneal exudate
::• [[Tumor necrosis factor-α]] (TNF-α)
::• [[Interleukin]] (IL)-1,6
::• [[Interferon-γ]] (IFN-γ)
::• [[Soluble adhesion molecules]]
:❑ Systemic and Abdominal manifestations of [[peritonitis]] mediated by '''[[cytokines]]'''<ref name="pmid11713936">{{cite journal| author=Such J, Hillebrand DJ, Guarner C, Berk L, Zapater P, Westengard J et al.| title=Tumor necrosis factor-alpha, interleukin-6, and nitric oxide in sterile ascitic fluid and serum from patients with cirrhosis who subsequently develop ascitic fluid infection. | journal=Dig Dis Sci | year= 2001 | volume= 46 | issue= 11 | pages= 2360-6 | pmid=11713936 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=11713936  }} </ref><ref name="pmid15138202">{{cite journal| author=Runyon BA| title=Early events in spontaneous bacterial peritonitis. | journal=Gut | year= 2004 | volume= 53 | issue= 6 | pages= 782-4 | pmid=15138202 | doi= | pmc=1774068 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15138202  }} </ref>
::• The effector molecules ('''[[Nitric oxide]]''') and [[cytokines]],'''[[Tumour necrosis factor]]''' (TNF) that help kill the bacteria have undesired side effects as they cause ''[[vasodilation]]'' and '''[[renal failure]]''' that accompany SBP.<ref name="pmid3894229">{{cite journal| author=Dunn DL, Barke RA, Knight NB, Humphrey EW, Simmons RL| title=Role of resident macrophages, peripheral neutrophils, and translymphatic absorption in bacterial clearance from the peritoneal cavity. | journal=Infect Immun | year= 1985 | volume= 49 | issue= 2 | pages= 257-64 | pmid=3894229 | doi= | pmc=262007 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=3894229  }} </ref><ref name="pmid11713936">{{cite journal| author=Such J, Hillebrand DJ, Guarner C, Berk L, Zapater P, Westengard J et al.| title=Tumor necrosis factor-alpha, interleukin-6, and nitric oxide in sterile ascitic fluid and serum from patients with cirrhosis who subsequently develop ascitic fluid infection. | journal=Dig Dis Sci | year= 2001 | volume= 46 | issue= 11 | pages= 2360-6 | pmid=11713936 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=11713936  }} </ref><ref name="NavasaFollo1998">{{cite journal|last1=Navasa|first1=Miguel|last2=Follo|first2=Antonio|last3=Filella|first3=Xavier|last4=Jiménez|first4=Wladimiro|last5=Francitorra|first5=Anna|last6=Planas|first6=Ramón|last7=Rimola|first7=Antoni|last8=Arroyo|first8=Vicente|last9=Rodés|first9=Joan|title=Tumor necrosis factor and interleukin-6 in spontaneous bacterial peritonitis in cirrhosis: Relationship with the development of renal impairment and mortality|journal=Hepatology|volume=27|issue=5|year=1998|pages=1227–1232|issn=02709139|doi=10.1002/hep.510270507}}</ref>
::• Studies have shown that the presence of whole bacteria or DNA, in serum and ascitic fluid leads to stimulation of immune defences, [[effector molecules]], and [[cytokines]] which in turn impact on [[hemodynamics]], renal function and survival.<ref name="pmid3894229">{{cite journal| author=Dunn DL, Barke RA, Knight NB, Humphrey EW, Simmons RL| title=Role of resident macrophages, peripheral neutrophils, and translymphatic absorption in bacterial clearance from the peritoneal cavity. | journal=Infect Immun | year= 1985 | volume= 49 | issue= 2 | pages= 257-64 | pmid=3894229 | doi= | pmc=262007 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=3894229  }} </ref></div>}}
{{familytree | | | |!| |}}
{{Familytree|boxstyle=background: #FFF0F5; color: #000000;width: 400px; text-align: left; font-size: 90%; padding: 0px;| | | F01 | |F01=<div style="padding: 15px;"><BIG>'''Host response'''</BIG>
:❑ Local response
Outpouring of fluid into the peritoneal cavity at sites of irritation with:
::• High protein content (>3 g/dL)
::• Many cells, primarily [[polymorphonuclear leukocytes]], that [[phagocytose]] and kill organisms
::• Formation of Fibrinous [[exudate]] on the inflamed peritoneal surfaces → Adhesion formation between adjacent bowel, [[mesentery]], and [[omentum]]
::• Localization of the inflammatory process is aided further by inhibition of motility in the involved intestinal loops
::• The extent and rate of intraperitoneal spread of contamination depend on the volume and nature of the [[exudate]] and on the effectiveness of the localizing processes
::• If peritoneal defenses aided by the appropriate supportive measures control the [[inflammatory]] process, the disease may resolve spontaneously ('''Sterile ascites''')<ref name="pmid4018735">{{cite journal| author=Runyon BA, Morrissey RL, Hoefs JC, Wyle FA| title=Opsonic activity of human ascitic fluid: a potentially important protective mechanism against spontaneous bacterial peritonitis. | journal=Hepatology | year= 1985 | volume= 5 | issue= 4 | pages= 634-7 | pmid=4018735 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=4018735  }} </ref><ref name="pmid4018735">{{cite journal| author=Runyon BA, Morrissey RL, Hoefs JC, Wyle FA| title=Opsonic activity of human ascitic fluid: a potentially important protective mechanism against spontaneous bacterial peritonitis. | journal=Hepatology | year= 1985 | volume= 5 | issue= 4 | pages= 634-7 | pmid=4018735 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=4018735  }} </ref><ref name="pmid8677940">{{cite journal| author=Ho H, Zuckerman MJ, Ho TK, Guerra LG, Verghese A, Casner PR| title=Prevalence of associated infections in community-acquired spontaneous bacterial peritonitis. | journal=Am J Gastroenterol | year= 1996 | volume= 91 | issue= 4 | pages= 735-42 | pmid=8677940 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8677940  }} </ref> → Consumption of humoral bactericidal factors due to frequent colonization → Increased susceptibility to '''SBP'''<ref name="pmid3257456">{{cite journal| author=Titó L, Rimola A, Ginès P, Llach J, Arroyo V, Rodés J| title=Recurrence of spontaneous bacterial peritonitis in cirrhosis: frequency and predictive factors. | journal=Hepatology | year= 1988 | volume= 8 | issue= 1 | pages= 27-31 | pmid=3257456 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=3257456  }} </ref>
::• If the ascitic fluid bactericidal activity is poor-moderate → '''Culture negative neutrocytic ascites''' (CNNA) or '''SBP''' → delay / inappropriate treatment → ''death'' due to [[sepsis]] and multi organ failure.<ref name="pmid3371881">{{cite journal| author=Runyon BA| title=Patients with deficient ascitic fluid opsonic activity are predisposed to spontaneous bacterial peritonitis. | journal=Hepatology | year= 1988 | volume= 8 | issue= 3 | pages= 632-5 | pmid=3371881 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=3371881  }} </ref><ref name="pmid6500513">{{cite journal | author = Runyon BA, Hoefs JC | title = Culture-negative neutrocytic ascites: a variant of spontaneous bacterial peritonitis | journal = Hepatology | volume = 4 | issue = 6 | pages = 1209–11 | year = 1984 | pmid = 6500513 | doi = 10.1002/hep.1840040619| url = | issn = }}</ref>
::• Second possible outcome is a confined '''[[abscess]]'''
::• A third possible outcome results when the peritoneal and systemic defense mechanisms are unable to localize the inflammation, which progresses to '''spreading diffuse [[peritonitis]]''' due to increased [[virulence]] of bacteria, greater extent and duration of contamination, and impaired host defenses.
:❑ Systemic response
[[Gastrointestinal]]
::• [[Paralysis]] of the bowel due to local [[inflammation]]
::• Progressive accumulation of fluid and electrolytes in the lumen of the adynamic bowel → distention of the bowel → inhibition of the capillary inflow and secretions
::• GI bleeding because of excessive [[inflammation]] and tissue damage → ↑ [[vasodilatation]] and ↓organ perfusion
[[Cardiovascular]]
::• Shift of fluid into the peritoneal cavity and bowel lumen → ↓ Effective circulating blood volume → ↑ [[Hematocrit]] and
::• ↑Fluid and electrolyte loss by coexistent [[fever]], [[vomiting]], [[diarrhea]] → decreased venous return to the right side of the heart → decrease in [[cardiac output]] → [[hypotension]] → activation of the [[sympathetic nervous system]] and manifestations such as [[sweating]], [[tachycardia]], and [[cutaneous]] [[vasoconstriction]] (i.e., cold, moist skin and mottled, [[cyanotic]] extremities).
::• If the blood volume replaced is sufficient enough as so to increase the [[cardiac output]] 2-3 times normal ( to satisfy the increased metabolic needs of the body in the presence of infection) a halt in the progression of the disease is seen.
::• Failure to sustain increased [[cardiac output]] results in progressive [[lactic acidosis]], [[oliguria]], [[hypotension]], and ultimately death if the [[infection]] cannot be controlled.
[[Respiratory]]
::• [[Intra-peritoneal]] [[inflammation]] → high and fixed [[diaphragm]] → pain on respiration → basilar [[atelectasis]] with intrapulmonary shunting of blood
::• Decompensation of [[respiratory]] function due to delay in the intervention → [[hypoxemia]] + [[hypo-capnia]] ([[respiratory alkalosis]]) followed by [[hypercapnia]] ([[respiratory acidosis]])
::• [[Pulmonary edema]] results because of increased pulmonary capillary leakage as a consequence of [[hypo-albuminemia]] or direct effects of bacterial toxins ([[adult respiratory distress syndrome]]) → progressive [[hypoxemia]] with decreasing pulmonary compliance which needs a [[ventilator]] assistance with increasingly higher concentrations of inspired [[oxygen]] and [[positive end-expiratory pressure]].
[[Renal]]
::• SBP → Splanchnic arterial [[vasodilation]] and systemic [[vascular resistance]] → ↓ Effective [[arterial]] blood volume → stimulation of systemic [[vasoconstrictors]] ([[RAAS]], [[Sympathetic Nervous System]], [[Arginine vasopressin]]) → renal [[vasoconstriction]]
::• Advanced [[cirrhosis]] → ↓ production of local [[vasodilators]] and ↑ production of local [[vasoconstrictors]]<ref name="pmid11713936">{{cite journal| author=Such J, Hillebrand DJ, Guarner C, Berk L, Zapater P, Westengard J et al.| title=Tumor necrosis factor-alpha, interleukin-6, and nitric oxide in sterile ascitic fluid and serum from patients with cirrhosis who subsequently develop ascitic fluid infection. | journal=Dig Dis Sci | year= 2001 | volume= 46 | issue= 11 | pages= 2360-6 | pmid=11713936 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=11713936  }} </ref> → Hepatorenal syndrome and death.<ref name="pmid15138202">{{cite journal| author=Runyon BA| title=Early events in spontaneous bacterial peritonitis. | journal=Gut | year= 2004 | volume= 53 | issue= 6 | pages= 782-4 | pmid=15138202 | doi= | pmc=1774068 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15138202  }} </ref>
::• ↓ Organ perfusion → [[Ischemic]] and Toxic [[Acute Tubular Necrosis]] → [[Acute Renal Failure]] → Death in (30-40%) of patients.
[[Metabolic]]
::• [[Infection]] → ↓body stores of [[Glycogen]] → catabolism of protein (muscle) and →extreme wasting and  rapid weight loss of severely infected patients
::• Infection → ↓Body heat production → exhaustion and death
[[Central nervous system]]
::• [[Hepatic Encephalopathy]] may occur due to [[inflammation]], [[Oxidative stress]] and Intestinal [[ammonia]] production on crossing the [[blood-brain barrier]] → [[altered mentation]].
[[Hematological]]
::• [[Sepsis]] → [[DIC]]</div>}}
{{family tree/end}}
|}
<br>
<br>


==Diagramatic representation of pathological bacterial translocation and the associated host response==
* '''[[Immunity suppression|Decreased immunity]]:''' both local and systemic immunity are decreased in [[Cirrhosis|cirrhotic patients]].
[[File:Pathological bacterial translocation.jpg|800px]]
===A. Bacterial overgrowth:===
* [[Motility|Intestinal motility]] decreases with [[cirrhosis]]. Increased [[Sympathetic control|sympathetic drive]] and [[Oxidant|oxidant stress]] are believed to be the reasons for the reduced mobility.
* Also, [[Cirrhosis|cirrhotic patients]] administer [[Proton pump inhibitor|PPIs]] more frequently than other patient populations.
* The diminished [[Motility|intestinal motility]] makes the intestinal contents more stagnant and allows the [[Bacteria|bacterial contents]] to overgrow and thus predisposes to SBP.<ref name="pmid9794900">{{cite journal |vauthors=Chang CS, Chen GH, Lien HC, Yeh HZ |title=Small intestine dysmotility and bacterial overgrowth in cirrhotic patients with spontaneous bacterial peritonitis |journal=Hepatology |volume=28 |issue=5 |pages=1187–90 |year=1998 |pmid=9794900 |doi=10.1002/hep.510280504 |url=}}</ref>


===B. Increased bowel permeability:===


Normally, the [[intestinal mucosa]] is impermeable to [[bacteria]] because of two lines of defense<ref name="pmid9794900">{{cite journal |vauthors=Chang CS, Chen GH, Lien HC, Yeh HZ |title=Small intestine dysmotility and bacterial overgrowth in cirrhotic patients with spontaneous bacterial peritonitis |journal=Hepatology |volume=28 |issue=5 |pages=1187–90 |year=1998 |pmid=9794900 |doi=10.1002/hep.510280504 |url=}}</ref>;the secretory component and physical component. Both are affected by the development of cirrhosis.
* The '''secretory defense''' mechanism is composed of [[Mucin|mucins]], [[immunoglobulins]] and [[bile salts]]. Bile salts are protective through preventing adherence and internalization of bacteria. [[Bile acid|Bile acids]] are decreased in cirrhosis partly due to reduced secretion from [[Cirrhosis|diseased liver]] and partly from [[Conjugation|increased conjugation]] by the flourishing [[intestinal flora]]. This gives bacteria easier access through the [[Mucosal|mucosa]] especially that [[E.coli]] (which is the most common strain isolated from SBP patients) has high ability to adhere to the [[intestinal mucosa]] and evade the host [[Immune system|immune defenses]].
* The physical component is the [[intestinal epithelium]] itself. [[Intestinal mucosa]] is more permeable as a result of increased [[Oxidant|oxidant stress]],[[Cytokines|NO proinflammatory cytokines]] & increased intercellular spaces as a result of [[vasodilation]], [[edema]] from [[portal hypertension]].


===C. Decreased local and systemic immune responses:===
* [[Kupffer cells]] (local [[macrophages]] of the liver) normally contribute in eradicating infection with [[neutrophils]]. But as a result of the extrahepatic portosystemic shunts, bacteria in the circulation do not come in contact with these cells.
* As a result of defective liver synthetic functions, [[complement]] levels decrease (both in [[serum]] and [[Ascites|ascitic fluid]]).
* The [[neutrophils]] seem to have declined [[Granulocyte|granulocyte functions]] as adherence, [[chemotaxis]], and bacterial killing.


 
Bacteria that translocate are carried through [[lymphatics]]. It can reach the [[Ascitic|ascitic fluid]] either through the circulation then through the liver. It can have access to the [[peritoneal cavity]]. Another way is through rupture of the [[lymphatic vessel]] carrying the contaminated lymph under pressure from [[portal hypertension]] and the increased [[lymph]] content.
<ref name="pmid6500513">{{cite journal | author = Runyon BA, Hoefs JC | title = Culture-negative neutrocytic ascites: a variant of spontaneous bacterial peritonitis | journal = Hepatology | volume = 4 | issue = 6 | pages = 1209–11 | year = 1984 | pmid = 6500513 | doi = 10.1002/hep.1840040619| url = | issn = }}</ref> Contrary to earlier theories, transmucosal migration of bacteria from the gut to the ascitic fluid is no longer considered to play a major role in the etiology of SBP.<ref name="pmid3371881">{{cite journal| author=Runyon BA| title=Patients with deficient ascitic fluid opsonic activity are predisposed to spontaneous bacterial peritonitis. | journal=Hepatology | year= 1988 | volume= 8 | issue= 3 | pages= 632-5 | pmid=3371881 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=3371881  }} </ref><ref name="pmid15920324">{{cite journal| author=Sheer TA, Runyon BA| title=Spontaneous bacterial peritonitis. | journal=Dig Dis | year= 2005 | volume= 23 | issue= 1 | pages= 39-46 | pmid=15920324 | doi=10.1159/000084724 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15920324  }} </ref>
 
With respect to compromised [[immune system|host defenses]], patients with severe acute or chronic liver disease are often deficient in [[Complement system|complement]] and may also have malfunctioning of the [[neutrophil]]ic and [[reticuloendothelial systems]].<ref name="pmid19561863">Alaniz C, Regal RE (2009) [https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&retmode=ref&cmd=prlinks&id=19561863 Spontaneous bacterial peritonitis: a review of treatment options.] ''P T'' 34 (4):204-10. PMID: [https://pubmed.gov/19561863 19561863]</ref>
 
As for the significance of ascitic fluid proteins, it was demonstrated that cirrhotic patients with ascitic protein concentrations below 1 g/dL were 10 times more likely to develop SBP than individuals with higher concentrations.<ref name="pmid3770358">Runyon BA (1986) [https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&retmode=ref&cmd=prlinks&id=3770358 Low-protein-concentration ascitic fluid is predisposed to spontaneous bacterial peritonitis.] ''Gastroenterology'' 91 (6):1343-6. PMID: [https://pubmed.gov/3770358 3770358]</ref> It is thought that the antibacterial, or opsonic, activity of ascitic fluid is closely correlated with the protein concentration.<ref name="pmid4018735">{{cite journal| author=Runyon BA, Morrissey RL, Hoefs JC, Wyle FA| title=Opsonic activity of human ascitic fluid: a potentially important protective mechanism against spontaneous bacterial peritonitis. | journal=Hepatology | year= 1985 | volume= 5 | issue= 4 | pages= 634-7 | pmid=4018735 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=4018735  }} </ref> Additional studies have confirmed the validity of the ascitic fluid protein concentration as the best predictor of the first episode of SBP.<ref name="pmid19561863"/>


==References==
==References==
{{reflist|2}}
{{reflist|2}}


{{WH}}
[[Category:Emergency mdicine]]
{{WS}}
[[Category:Disease]]
 
[[Category:Up-To-Date]]
[[Category:Gastroenterology]]
[[Category:Emergency medicine]]
[[Category:Infectious disease]]
[[Category:Infectious disease]]

Latest revision as of 00:15, 30 July 2020

Peritonitis main page

Spontaneous bacterial peritonitis Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Spontaneous bacterial peritonitis from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

History & Symptoms

Physical Examination

Laboratory Findings

Electrocardiogram

Chest X Ray

CT

MRI

Echocardiography or Ultrasound

Other Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Spontaneous bacterial peritonitis pathophysiology On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Spontaneous bacterial peritonitis pathophysiology

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Spontaneous bacterial peritonitis pathophysiology

CDC on Spontaneous bacterial peritonitis pathophysiology

Spontaneous bacterial peritonitis pathophysiology in the news

Blogs on Spontaneous bacterial peritonitis pathophysiology

Directions to Hospitals Treating Spontaneous bacterial peritonitis

Risk calculators and risk factors for Spontaneous bacterial peritonitis pathophysiology

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Shivani Chaparala M.B.B.S [2] Ahmed Younes M.B.B.CH [3]

Overview

Intestinal bacterial overgrowth in cirrhotic patients, defective intestinal barrier and defective host immune response are the 3 determinant factors for bacterial translocation explaining SBP.

Pathogenesis

Three factors play a role in the pathogenesis of SBP:

A. Bacterial overgrowth:

B. Increased bowel permeability:

Normally, the intestinal mucosa is impermeable to bacteria because of two lines of defense[2];the secretory component and physical component. Both are affected by the development of cirrhosis.

C. Decreased local and systemic immune responses:

Bacteria that translocate are carried through lymphatics. It can reach the ascitic fluid either through the circulation then through the liver. It can have access to the peritoneal cavity. Another way is through rupture of the lymphatic vessel carrying the contaminated lymph under pressure from portal hypertension and the increased lymph content.

References

  1. Căruntu FA, Benea L (2006). "Spontaneous bacterial peritonitis: pathogenesis, diagnosis, treatment". J Gastrointestin Liver Dis. 15 (1): 51–6. PMID 16680233.
  2. 2.0 2.1 Chang CS, Chen GH, Lien HC, Yeh HZ (1998). "Small intestine dysmotility and bacterial overgrowth in cirrhotic patients with spontaneous bacterial peritonitis". Hepatology. 28 (5): 1187–90. doi:10.1002/hep.510280504. PMID 9794900.