Inflammation is the first response of the immune system to infection or irritation and may be referred to as the innate cascade. Inflammation is characterised by the following quintet: redness (rubor), heat (calor), swelling (tumor), pain (dolor) and dysfunction of the organs involved (functio laesa). The first four characteristics have been known since ancient times and are attributed to Celsus; functio laesa was added to the definition of inflammation by Rudolf Virchow in 1858.

Inflammation is not a synonym for infection. Even in cases when it is caused by infection it is incorrect to use the terms as synonyms—both describe different problems or different aspects of a problem.

3-Nitrotyrosine (NT)

• an inflammation-associated marker that is formed by nitration of protein tyrosine residues with peroxynitrite generated during inflammation. PMID: 15585307

5'-Nucleotidase

• a marker of both general and local inflammation in rheumatoid arthritis patients. PMID: 10371274

8-oxo-dG

• leads to intracellular oxidative damage on the nucleotide pool, thus providing a sensitive marker for inflammatory response. PMID: 17034359

Activin A

• a novel player and inflammatory marker in inflammatory bowel disease. PMID: 9354766

Adenosine

• a potential surrogate marker of airway inflammation. PMID: 12952279

AIF-1 (allograft inflammatory factor-1)

• a marker of activated human vascular smooth muscle cells and arterial injury. PMID: 10894811

Alpha1-Acid Glycoprotein (alpha1-AG)

• a chronic inflammation marker. PMID: 16235835

B2-M (B2 microglobulin)

• a reliable marker of activity in inflammatory bowel disease. PMID: 11467650
• an immunogenetic marker of inflammatory and malignant origin. PMID: 6185038

Calprotectin

• a fecal marker for diagnosis and follow-up in patients with chronic inflammatory bowel disease. PMID: 14677476
• may be used as an inflammatory marker in patients with reactive arthritis. PMID: 7774104
• a marker of inflammation in cystic fibrosis. PMID: 8660076

Cathepsin X

• a potential new inflammatory marker. PMID: 16376371

CD16 (Fc gamma RIII)

• a novel marker of acute inflammatory glomerular injury.PMID: 10231456

CD40 ligand (L) and CD62 P-selectin (P)

• platelet inflammatory marker. PMID: 15019868

CD83

• serve as a marker to differentiate between acute and chronic inflammation. PMID: 12452842

CGRP (Calcitonin gene-related peptide)

• one of several neuropeptides known to be involved in neurogenic inflammation. PMID: 9415506

CRP (C-reactive protein)

• a acute inflammation marker. PMID: 16235835
• the prototype of acute-phase protein which is secreted by the liver in response to a variety of inflammatory cytokines. PMID: 14650743
• the major acute phase reactant during inflammation. PMID: 2170808
• a marker for inflammatory bowel disease. PMID: 15472532
• a valuable unbiased marker of inflammatory activity during steroid treatment in canine immune-mediated polyarthritis (IMPA). PMID: 16987405  
• an objective marker of inflammation and, in gastrointestinal diseases such as Crohn's disease and acute pancreatitis, its levels correlate well with clinical disease activity. PMID: 16327837
• not only an inflammatory marker but also a direct cause of cardiovascular diseases. PMID: 15050096
• a stable marker of inflammation that has been shown to be predictive of cardiovascular morbidity. PMID: 14975482
• marker of inflammation in atherosclerosis. PMID: 12494114
• a sensitive marker of inflammation, as a risk factor for stable coronary artery disease. PMID: 11440732
• a 'golden marker' for inflammation and coronary artery disease. PMID: 11405613
• a marker of chronic inflammation in uremic patients. PMID: 10859421
• a marker for infection and inflammation in regular dialysis patients. PMID: 9438096

ECP (eosinophil cationic protein)

• an eosinophilic inflammatory marker. PMID: 11862965, PMID: 11676135
• Total ECP concentration seems to reflect the eosinophilic inflammatory changes in asthma and might be a useful tool in clinical practice. PMID: 16095147
• a marker of nasal inflammation in patients with cystic fibrosis. PMID: 10522945
• a marker of eosinophilic inflammation in asthma. PMID: 9515598, PMID: 9260219

Elastase

• a predictive marker of inflammation and/or infection. PMID: 15103678

Elastase-Inhibitor Complex (s-EI)

• a marker of male genital tract inflammation. PMID: 15595956
• seminal elastase-inhibitor complex (Ela/alpha1-PI) has been proposed as a marker of male silent genital tract inflammation. PMID: 12636042

eNO (Exhaled nitric oxide)

• can be used in epidemiologic studies as a noninvasive marker of allergic airway inflammation in schoolchildren. PMID: 15356549
• a useful marker of airway inflammation for differential diagnosis and evaluation of severity in steroid-naive patients with bronchial asthma, it may not be as useful in steroid-treated patients. PMID: 11124647
• marker of inflammation in children with asthma. PMID: 10641534
• a new marker of airway inflammation. PMID: 9046169

E-selectin

• a reliable marker of inflammation in lumbar disc disease. PMID: 15809889

Faecal Calprotectin

• a promising and non-invasive biomarker of intestinal inflammation. PMID: 14563186
• a marker of inflammation throughout the intestinal tract. PMID: 12172403, PMID: 12172400

Fas (Soluble)

• sFas is a potent surrogate marker of inflammatory process activity in Graves' ophthalmopathy, however it has no prognostic value in the prediction of the immunotherapy efficacy. PMID: 15690704
• a novel marker of inflammation in uremia. PMID: 12911341

Fibrinogen

• a marker of inflammatory response. PMID: 9437834

Fibrin

• a possible marker for underlying inflammatory processes. PMID: 8789908

Fibronectin (FN)

• may mark the existence of pathologic lung processes associated with inflammation and, perhaps tissue repair after bronchopulmonary injury. PMID: 9670297

gamma-Glutamyl transpeptidase (gamma-GT)

• a novel biochemical marker in inflammation. PMID: 2877669

HC gp39 (human cartilage glycoprotein 39)

• Serum human cartilage glycoprotein 39 as a marker of arthritis associated with inflammatory bowel disease. PMID: 14644865

Hepcidin

• an acute-phase protein and a marker of inflammation in kidney transplant recipients with and without coronary artery disease. PMID: 17112858

HLA-DR

• a marker for increased risk for systemic inflammation and septic complications after cardiac surgery. PMID: 12802492

Human-Beta Defensin 2 (hBD2)

• a molecular marker of gastric mucosal inflammation. PMID: 16201065

Human Neutrophil Lipocalin (HNL)

• a unique marker of neutrophil inflammation in ulcerative colitis and proctitis. PMID: 11889070

Hyperthermia

• a surrogate marker of inflammation-mediated cause of brain damage in acute ischaemic stroke. PMID: 16961671

Hyaluronate

• Serum hyaluronate was the best predictor of extensive liver fibrosis and inflammation and it could discriminate subgroups of patients with chronic hepatitis B. PMID: 16221307

ICAM-1 (intercellular adhesion molecule-1)

• a consistent inflammatory parameter of the cutaneous radiation reaction both in vitro and in vivo that might provide new therapeutic options for diagnosis and treatment of effects of radiation. PMID: 16965414
• a marker of vascular inflammation and lifestyle. PMID: 15919214

IL-6 (interleukin-6)

• an early marker of the inflammatory response. PMID: 14574073
• a potential inflammatory marker after total joint replacement. PMID: 11081839
• may be useful for early detection of acute inflammation. PMID: 7531252
• a marker of active inflammation and ongoing glomerular injury. PMID: 10631097
• play an active role in the postinjury immune response, making it an attractive therapeutic target in attempts to control hyperinflammatory provoked organ injury. PMID: 8916880

IL-6 Receptor

• Soluble IL-6R-mediated signaling is therefore an important intermediary in the resolution of inflammation and supports transition between the early predominantly neutrophilic stage of an infection and the more sustained mononuclear cell influx. PMID: 11420041

IL-10

• Play a vital role in the control of CD4(+) T cell mediated inflammation in the brain during TE. PMID: 16005735
• an important regulator of the inflammatory response to P. aeruginosa endobronchial infection. PMID: 10588626
• inhibits the synthesis of proinflammatory cytokines known to be involved in fever, including IL-1, IL-6, and tumor necrosis factor-alpha. PMID: 9917866

IL-18

• an important cofactor in Th1 immune responses and it has additional roles in inflammation. PMID: 16519734
• play a major role in autoimmune and inflammatory human disease. PMID: 15174967
• functions as a proinflammatory cytokine in this model of acute lung inflammation, serving as an autocrine activator to bring about expression of other inflammatory mediators. PMID: 11739527

LAA (leucocyte adhesiveness/aggregation)

• an early and sensitive marker of inflammation and that it can be used as a marker for the presence of pulmonary leukostasis during thermal injury. PMID: 1793493

Lactoferrin

• the most suitable of these proteins for use as a neutrophil-derived whole gut lavage fluid (WGLF) marker of intestinal inflammation. PMID: 11866274
• The fecal lactoferrin ELISA provides a non-invasive, quantitative assessment of intestinal inflammation. PMID: 16806255
• Fecal lactoferrin is sensitive and specific for detecting inflammation in chronic inflammatory bowel disease (IBD). PMID: 12818275

LBP (Lipopolysaccharide binding protein)

• a marker of synovial inflammation. PMID: 7562749

Leptin

• a local inflammatory marker in chronic obstructive pulmonary disease (COPD). PMID: 15672852

Lipocalin-2

• an Inflammatory Marker Closely Associated with Obesity, Insulin Resistance, and Hyperglycemia in Humans. PMID: 17040956

Malondialdehyde (MDA)

• a sensitive marker of inflammation in patients with rheumatoid arthritis. PMID: 7876045

MDC (macrophage-derived chemokine)

• serum MDC concentration may be a useful inflammatory marker for assessing atopic dermatitis (AD) severity in infants and young children. PMID: 12911508

MMP-9

• a novel marker of inflammation in patients with known coronary artery disease and might provide an index of plaque activity in this clinical setting. PMID: 14577520
• a marker of inflammation in tracheal epithelial lining fluid (TELF) and in bronchoalveolar fluid (BALF) of COPD horses. PMID: 11266061

Monocyte Chemoattractant Protein-1 (MCP-1)

• a reliable marker of inflammation in hepatic derangements. PMID: 16242682
• a marker for joint inflammation in rheumatoid arthritis. PMID: 11196541

Monocyte Cluster Domain 163

• Soluble monocyte cluster domain 163, a new global marker of anti-inflammatory response, is elevated in the first trimester of pregnancy. PMID: 15140143

M-PLA2 (membrane-associated phospholipase A2)

• an acute phase reactant and a sensitive and useful marker of inflammation in rheumatoid arthritis. PMID: 1636052

MRP8/14

• a sensitive marker for inflammatory responses associated with transplant rejection. PMID: 12651812

Myeloperoxidase

• a marker of increasing systemic inflammation in smokers without severe airway symptoms. PMID: 17098408

Neopterin

• a marker of myocardial inflammation and unfavourable prognosis in patients with a clinical diagnosis of dilated heart muscle disease. PMID: 1915446

Nitric Oxide (NO)

• an inflammatory marker in asthma. PMID: 12371528
• airborne NO may be looked upon as a marker of inflammation and as an aerocrine messenger in humans. PMID: 8876755
• a noninvasive marker of airway inflammation in asthma. PMID: 15876594
• a marker of airway inflammation in asthmatic subjects. PMID: 10457119

Nitrotyrosine

• widely recognized as a surrogate marker of up-regulated inducible NO synthase expression at sites of inflammation. PMID: 12847213

p53

• a prognostic marker in inflammatory breast cancer. PMID: 15448010

Pentraxin 3 (PTX-3, PTX3)

• a marker of inflammation in untreated psoriatic patients. PMID: 16865225

PK11195

• The peripheral benzodiazepine receptor ligand PK11195 has been used as an in vivo marker of neuroinflammation in positron emission tomography studies in man. PMID: 12623120

Prealbumin

• an inflammatory marker for patients with deep space infections of odontogenic origin. PMID: 16487796

Procalcitonin (PCT)

• a marker of the systemic inflammatory response to infection. PMID: 15252237
• a marker of systemic inflammatory reaction after isolated extremity perfusion. PMID: 14518284
• is a more reliable marker than CRP in defining infection as a cause of systemic inflammatory response. PMID: 12500512
• a marker to clearly differentiate systemic inflammatory response syndrome and sepsis in the critically ill patient. PMID: 12209289
• a marker and mediator of inflammation. PMID: 16033153
• a marker of inflammation, is elevated in the maternal but not in the fetal circulation in preeclampsia. PMID: 16021084
• a marker of micro-inflammation in hemodialysis. PMID: 16013016
• a new marker of inflammation in haemodialysis patients. PMID: 11328904
• a marker of systemic inflammation after conventional or minimally invasive coronary artery bypass grafting. PMID: 9714487

proMMP-9 (matrix metalloproteinase-9 proenzyme)

• a novel early indicator of acute host-response in pleural space that complements traditional proinflammatory markers and might be useful in monitoring pleural inflammatory processes. PMID: 15204835

RANKL protein

• is significantly increased both locally and systemically during the earliest stages of inflammatory arthritis in rats, suggesting that serum RANKL might have prognostic value for bone erosions and systemic osteopenia in this condition. PMID: 16160733

Rel B

• an early marker of autoimmune islet inflammation in the biobreeding (BB) rat. PMID: 10630383

Resistin

• a plasma protein, induces insulin resistance in rodents, is an inflammatory marker of atherosclerosis in humans. PMID: 15710760

Serum Amyloid A (SAA)

• Serum amyloid A protein is a useful inflammatory marker during late-onset sepsis in preterm infants. PMID: 15539766
• a novel serum marker for the detection of systemic inflammatory response in cystitis.PMID: 12913703
• Evaluation of feline serum amyloid A (SAA) as an inflammatory marker. PMID: 12736442
• an inflammatory marker in equine influenza virus infection. PMID: 10918902
• a marker of adiposity-induced low-grade inflammation but not of the metabolic status of obese subjects. PMID: 16571858

Tenascin

• a useful marker in the diagnosis of inflammatory myopathies. PMID: 9620889

TG2 (tissue transglutaminase)

• can be a marker of inflammatory myopathies. PMID: 15752564

Thrombospondin

• a marker of inflammation and early fibrosis. PMID: 7515560

TNF-alpha (tumor necrosis factor-alpha)

• a noninvasive marker of liver inflammation in patients with viral hepatitis C. PMID: 12380024
• a marker of intestinal inflammation. PMID: 1345871

Tryptase

• serum tryptase detected with B12 antibody is a marker of allergic airway inflammation in asthma. PMID: 12095181

TSA (Total Sialic Acid)

• an inflammation marker associated with a history of deep vein thrombosis. PMID: 16500696

Uric Acid

• a marker of chronic inflammation. PMID: 9886724

YKL-40

• secreted by macrophages and neutrophils and is a growth factor for vascular endothelial cells and fibroblasts. Elevated serum concentrations of YKL-40 are found in patients with diseases characterized by inflammation or ongoing fibrosis, is a potential new marker of disease activity in patients with inflammatory bowel disease.PMID: 12825867
• a new inflammatory marker with relation to insulin resistance and with a role in endothelial dysfunction and atherosclerosis. PMID: 16955240
• a marker of joint involvement in inflammatory bowel disease. PMID: 14500601

Other Inflammatory Markers

• Cerebrospinal fluid antimicroglial antibodies in Alzheimer disease: A putative marker of an ongoing inflammatory process.  PMID: 17140756       
• Triggering receptor expressed on myeloid cells-1 in pleural effusions: A marker of inflammatory disease. PMID: 17097866
• Cheilitis glandularis: a clinical marker for both malignancy and/or severe inflammatory disease of the oral cavity. PMID: 16443070
• Fetal thymic involution: a sonographic marker of the fetal inflammatory response syndrome. PMID: 16389025
• CO-Hb (carboxyhemoglobin) concentrations can, in general, reflect the inflammatory response induced by surgical insult; however, CO-Hb measurement may not be a useful form of clinical monitoring because of the limited degree of changes, the variation of baseline values, and the necessity for the management under fixed conditions. PMID: 15834204
• Erythrocyte mean corpuscular volume as a surrogate marker for 6-thioguanine nucleotide concentration monitoring in patients with inflammatory bowel disease treated with azathioprine or 6-mercaptopurine. PMID: 12902847
• Value of eosinopenia in inflammatory disorders: an "old" marker revisited. PMID: 12829215
• serum uric acid may reflect the severity of systolic dysfunction and the activation of an inflammatory reaction in patients with congestive heart failure. PMID: 12238311
• lower serum Zn is a marker of TRD and of the immune/inflammatory response in depression. PMID: 9276075
• Enteric protein loss as a marker of intestinal inflammatory activity in Crohn's disease: comparability of enteric clearance and stool concentration of alpha-1-antitrypsin? PMID: 1441675
• redistribution of cellular metals is an extremely sensitive marker of an inflammatory process not evident by clinical symptoms or increase of acute phase plasma proteins. PMID: 3258920
• Endogenous peroxidases: a morphological and functional marker to study inflammatory skin diseases. PMID: 6158981
• Serum copper as a marker of inflammation in prediction of short term outcome in high risk patients with chronic heart failure. PMID: 16843542
• plasma DNA may be a sensitive marker for overtraining-induced inflammation. PMID: 16840584
• Erythrocyte sedimentation rate as a marker of inflammation and ongoing coagulation in stroke and transient ischaemic attack. PMID: 16201006
• EBC (exhaled breath condensate) H(2)O(2) might be used as non-invasive biomarker for monitoring lower airway inflammation. PMID: 15848781
• The increase of leukocytes as a new putative marker of low-grade chronic inflammation and early cardiovascular risk in polycystic ovary syndrome. PMID: 15483098
• the measurement of EBC pH may be useful in the evaluation of airway inflammation in children with asthma and CF. PMID: 15189915
• PMN migration proved to be a highly sensitive predictive marker for infections. PMID: 14727016
• Exercise-induced asthma in children: a marker of airway inflammation. PMID: 12225263
• Generalized lymphadenopathy as a marker of ongoing inflammation in prolonged cholestatic hepatitis A. PMID: 12172409
• Faster rise of exhaled breath temperature in asthma: a novel marker of airway inflammation. PMID: 11790651
• Hydrogen peroxide--a marker for respiratory tract inflammation in patients with bronchial asthma. PMID: 11201826
• Magnetic resonance imaging (MRI) as a marker of inflammation, destruction and prognosis in rheumatoid arthritis wrists. PMID: 10962915
• Anti asialoglycoprotein receptor antibodies and soluble interleukin-2 receptor levels as marker for inflammation in autoimmune hepatitis. PMID: 9123953
• elevation of H2O2 in the expired breath condensate is a simple, noninvasive method that can be used as a biochemical marker of airway inflammation. PMID: 8214950
• 99mTc-nanocolloid is a promising substance for the scintigraphic demonstration of inflammatory foci. PMID: 2849165
• Complement activation in systemic lupus erythematosus: a marker of inflammation. PMID: 3487647
• Circulating activated lymphocytes in rheumatoid arthritis: a marker of synovial inflammation. PMID: 7097680