Bacterial infections other than spontaneous bacterial peritonitis in cirrhosis

Table 1 Immune dysfunction in cirrhotic patients

Natural barriers	Fragile, thin and/or edematous skin Alteration of gastrointestinal motility, mucosal permeability and bacterial flora ↑ Gastrointestinal mucosal ulcerations
Hepatic RES activity	Portosystemic shunting Kupffer cells –↓ number, impaired function
Cellular defense mechanisms	RES –↓ activation, ↓ chemotaxis, ↓ phagocytosis, ↓ production of pro-inflammatory cytokines PMN –↓ lifespan, ↓ intracellular killing activity, ↓ phagocytosis, ↓ chemotaxis
Serum factors	↓ Complement levels (C3, C4, CH50) ↓ Opsonic activity ↓ Protein C activity
Iatrogenic and treatment-related factors	Invasive procedure and catheters Medications: immunosuppressive agents, proton pump inhibitors
Other compelling factors	Malnutrition Alcohol drinking

RES: Reticuloendothelial system; PMN: Polymorphonuclear neutrophil.

Table 2 Individual pathogens and their clinical manifestations in cirrhotic patients

Pathogens	Common clinical features	Key points
E.coli, Klebsiella spp. Enterobacter spp. and other gram-negative enteric bacteria[6,7,9,12,13]	SBP, bacteremia, UTI, biliary tract infection, meningitis	↑ Incidence of resistant organisms in hospital-acquired infection and in patients taking prophylactic quinolones
Plesiomonas shigelloides [10,81,99]	Septicemia, diarrhea, SBP, meningitis, SSTI	↑ Incidence in hemochromatosis Risk factors: contaminated food and water
Vibrio spp. (V. vulnificus, non-o1 V. cholera, V. parahemolyticus)[10,42,43,57,81]	SSTI, bacteremia, gastroenteritis	↑ Incidence in cirrhosis, particularly hemochromatosis ↑ Virulence; mortality 50%-60% in bacteremic form and about 24% for SSTI Risk factors: contaminated food and seawater
Aeromonas spp. (A. hydrophilla, A. sobria)[44,45,67,70-72]	Bacteremia, biliary tract infection, gastroenteritis, SBP, SSTI	↑ Incidence ↑ Virulence; mortality 20%-60% Risk factors: contaminated food and water
Yersinia spp. (Y. enterocolitica, Y. pseodotuberculosis)[10,81]	Bacteremia, SBP, hepatosplenic abscesses	↑ Incidence in hemochromatosis ↑ Virulence; mortality about 50% in bacteremic form
Campylobacter spp. (C. jejuni, C. fetus)[10,100]	Bacteremia, SBP	↑ Incidence Mortality about 10% in bacteremic form
Pateurella multocida[13,101,102]	SSTI, bacteremia, arthritis, meningitis	↑ Incidence Mortality about 10% in bacteremic form Risk factors: cat and dog bites or scratches
Staphylocccus aureus[7,11,13]	Bacteremia, SSTI, endocarditis	↑ Incidence, particularly in those who are hospitalized and/or had invasive procedure ↑ Incidence of MRSA carriage and infection
Streptococcus pneumonia[94,95]	Bacteremia, pneumonia, SBP, SSTI, meningitis	↑ Incidence of invasive pneumococcal disease ↑ Virulence Vaccination is recommended
Streptococcus group B[103,104]	Bacteremia, SBP, SSTI, pneumonia	↑ Incidence Mortality 10%-25%
Clostridium difficile[80]	Antibiotic-associated diarrhea and colitis	↑ Incidence ↑ Virulence; mortality 14% Risk factors: hospitalization, antibiotics, proton pump inhibitors
Clostridium spp. (C. perfringens, C. bifermentans, C. septicum)[13,105]	Bacteremia, SSTI, peritonitis	↑ Incidence ↑ Virulence; mortality 54%-65%
Enterococcus spp (E. faecium, E. faecalis, E. galinarum)[7,11,59,106-109]	SBP, bacteremia, UTI, endocarditis, biliary tract infection	↑ Incidence, particularly in hospital-acquired infection and in patients taking prophylactic quinolones ↑ Virulence; mortality rate up to one third in bacteremic form and up to 60% in enterococcal peritonitis Pre-transplant VRE colonization (13%-15% from surveillance) is associated with increased morbidity and mortality following liver transplant
Listeria monocytogenes[10,64,81]	Bacteremia, meningitis, SBP	↑ Incidence in cirrhosis, particularly hemochromatosis
Mycobacterium tuberculosis (TB)[73,74,77]	Pulmonary TB, extra-pulmonary TB (e.g. peritonitis, disseminated TB)	↑ Incidence ↑ Virulence; mortality 22%-48% ↑ Extra-pulmonary forms ↑ Risk for multi-drug resistance TB ↑ Risk for anti-TB hepatotoxicity

SBP: Spontaneous bacterial peritonitis; UTI: Urinary tract infection; SSTI: Skin and soft tissue infection; TB: Tuberculosis.