Adhesion molecule expression and the inflammatory cell infiltrate in delayed pressure urticaria

Markers for the involvement of endothelial cells and the coagulation system in chronic urticaria: A systematic review

Chronic urticaria (CU) is a chronic inflammatory mast cell-driven disorder. Endothelial cells (ECs) contribute importantly to key features of CU. Several markers of EC (dys)function in CU have been reported, but have not yet been systematically reviewed. In this study, we systematically reviewed and categorized all published markers of EC functions in CU through a comprehensive search in Pubmed, The Cochrane Library, Web of Science, and SCOPUS using the following Mesh terms: CU AND pathogenesis AND (vasculopathy OR microangiopathy OR ECs OR marker). In total, 79 articles were selected and the identified biomarkers were categorized according to EC (dys)function in CU. The most frequent and consistently reported upregulated biomarkers in CU skin were adhesion molecules, TF, and P-selectin. The most frequently reported upregulated and reliable biomarkers in sera of CU patients were F1+2 for coagulation cascade involvement, D-dimers for fibrinolysis, and MMP-9 for vascular permeability. Emerging biomarkers described in the selected articles were endostatin, heat shock proteins, cleaved high molecular weight kininogen, and adipokines. This systematic review contributes to the pool of growing evidence for vascular involvement in CU where EC dysfunction is present in different aspects of cell survival, maintenance of vascular structure, and coagulation/fibrinolysis balance.

Successful treatment of delayed pressure urticaria with 300 mg of omalizumab every 14 days

Delayed pressure urticaria is a rare form of chronic inducible urticaria characterized by erythematous-painful plaques that develop in areas of the skin exposed to prolonged pressure. Its treatment is very difficult, and its response to antihistamines is variable. Cases of delayed pressure urticaria, which have been completely controlled with the use of omalizumab in recent years, have been reported.

Delayed Pressure Urticaria: A Systematic Review of Treatment Options

BACKGROUND

Delayed pressure urticaria (DPU) is characterized by recurrent erythematous and often painful swelling after the skin is exposed to sustained pressure. Treatment is challenging. Antihistamines, the first-line and only approved treatment, are often not effective.

OBJECTIVE

To systematically review the treatment options for DPU.

METHOD

A literature search of electronic databases for all relevant articles published till April 29, 2019, was conducted using the search terms "delayed pressure urticaria" and "pressure urticaria." This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations.

RESULTS

Twenty-one studies (8 randomized controlled trials [RCTs], 10 retrospective cohort studies, and 3 open-label prospective studies) were included. Second-generation H₁ antihistamines (sgAHs) were effective in 3 RCTs. The combination of an sgAH and montelukast (2 RCTs) or an sgAH and theophylline (1 non-RCT) was more effective than the sgAH alone. The disease improved with omalizumab (4 non-RCTs), sulphones (3 non-RCTs), oral prednisolone (1 RCT and 2 non-RCTs), intravenous immunoglobulin (1 non-RCT), and gluten-free diet (1 non-RCT). There are no studies on updosing of antihistamines over standard dosage in DPU.

CONCLUSIONS

Overall, the quality of studies on DPU is low. Because of the lack of other evidence, antihistamines remain the first-line therapy. Updosing of sgAHs could be considered in patients with uncontrolled symptoms on the basis of the extrapolation of evidence from chronic spontaneous urticaria, even though there is no evidence of its efficacy over standard dosage. Addition of montelukast may be considered. Omalizumab or sulphones may be used in treatment-resistant patients. High-quality DPU studies should be conducted.

Review of Physical Urticarias and Testing Methods

PURPOSE OF REVIEW

This review aims to update the information available on the prevalence, clinical picture, diagnostic methods, and treatment of urticarias induced by external physical stimuli.

RECENT FINDINGS

Physical urticarias are present in up to 5% of the general population, and in 10 to 50% of patients with chronic urticaria. Recent investigations have provided evidence that the presence of physical urticaria alone or when comorbid with chronic spontaneous urticaria is associated with a worse prognosis and duration. Most frequent subtypes of physical urticaria are dermographism and delayed pressure urticaria. The diagnosis is established through specific provocation tests and the management encompasses avoidance measures, pharmacologic therapy with nonsedating antihistamines, and alternative medications in refractory cases.

Looking forward to new targeted treatments for chronic spontaneous urticaria

The introduction of omalizumab to the management of chronic spontaneous urticaria (CSU) has markedly improved the therapeutic possibilities for both, patients and physicians dealing with this disabling disease. But there is still a hard core of patients who do not tolerate or benefit from existing therapies and who require effective treatment. Novel approaches include the use of currently available drugs off-licence, investigational drugs currently undergoing clinical trials and exploring the potential for therapies directed at pathophysiological targets in CSU. Off-licence uses of currently available drugs include rituximab and tumour necrosis factor inhibitors. Ligelizumab (anti-IgE), canakinumab (anti-IL-1), AZD1981 (a PGD2 receptor antagonist) and GSK 2646264 (a selective Syk inhibitor) are currently in clinical trials for CSU. Examples of drugs that could target potential pathophysiological targets in CSU include substance P antagonists, designed ankyrin repeat proteins, C5a/C5a receptor inhibitors, anti-IL-4, anti-IL-5 and anti-IL-13 and drugs that target inhibitory mast cell receptors. Other mediators and receptors of likely pathogenic relevance should be explored in skin profiling and functional proof of concept studies. The exploration of novel therapeutic targets for their role and relevance in CSU should help to achieve a better understanding of its etiopathogenesis.

A Review of the Use of Infliximab to Manage Cutaneous Dermatoses

Background:

Infliximab is a chimeric monoclonal antibody that binds specifically to human tumor necrosis factor-alpha (TNF-α), decreasing the effect of the cytokine in inflammatory diseases.

Objective:

The aim of this study was to review the efficacy and safety of infliximab in the treatment of dermatological diseases.

Methods:

A MEDLINE search (1966–January 2003), using the keyword “infliximab” was performed to find relevant articles pertaining to the use of infliximab in dermatology.

Results:

Infliximab has been used in the following dermatological diseases: psoriasis, Behçet's disease, graft versus host disease, hidradenitis suppurativa, panniculitis, pyoderma gangrenosum, SAPHO (synovitis, acne, pustulosis, hyperostosis and osteitis) syndrome, sarcoidosis, subcorneal pustular dermatosis, Sweet's syndrome, toxic epidermal necrolysis, and Wegener's granulomatosis. There is a generally good safety profile for infliximab, which is similar to that when it is used to treat Crohn's disease and rheumatoid arthritis.

Conclusion:

Although not approved for use in dermatological diseases, there have been numerous reports of the efficacy of infliximab in cutaneous inflammatory diseases. The most promise lies in those diseases that have increased amounts of TNF-α in the cutaneous lesions, such as psoriasis.

Therapy of chronic urticaria: a simple, modern approach

OBJECTIVE

To examine the available treatment choices for chronic spontaneous urticaria (CSU) and discuss a new paradigm for treating such patients.

DATA SOURCES

The literature regarding treatment is reviewed, including considerations of published guidelines. Attention is focused on the most recent evidence indicating particular efficacy of omalizumab.

RESULTS

Omalizumab has been found to have considerable efficacy in phase 2 and phase 3 trials in which more than 900 patients have been studied. A response rate of 65% is seen in patients resistant to antihistamines as well as to histamine2 blockers and leukotriene antagonists, and 40% of patients are completely free of hives as long as therapy is continued. In addition, serious adverse events have not been seen. Only cyclosporine can match this response rate (excluding steroids), but the adverse effect profile (blood pressure and renal function) is substantial by comparison. Double-blind, placebo-controlled studies of other agents often listed as alternatives are lacking (ie, whether their success rate exceeds the 25%-30% placebo response is uncertain). The mechanism by which omalizumab works in CSU is not clear because the response rate is unrelated to the autoimmune profile and can occur rapidly (ie, within a few days).

CONCLUSION

Omalizumab has exceptional efficacy for antihistamine-resistant CSU with an excellent adverse effect profile.

Differential diagnosis of chronic urticaria

OBJECTIVES

To review diseases that can present with cutaneous signs and symptoms that mimic those observed in chronic urticaria and to discuss the workup necessary to distinguish these diseases from chronic urticaria.

DATA SOURCES

We performed a PubMed search using the following keywords: urticaria, cryopyrin, Sweet syndrome, subacute cutaneous lupus, urticarial vasculitis, urticaria pigmentosa, angioedema, fixed drug eruption, bullous pemphigoid, and reticular erythematous mucinosis. Appropriate chapters in general dermatology textbooks were also reviewed.

STUDY SELECTION

Articles that related to disease states, which present with persistent urticarial lesions, were catalogued for use in this review.

RESULTS

Besides acute, chronic, and physical urticarias, there are 2 categories of diseases that have urticarial lesions. The first group includes those in which the skin lesions are almost indistinguishable from those seen in patients with chronic idiopathic urticaria. Thus, the diagnosis relies on a careful history and physical examination, and in some cases laboratory studies are required. The second group are ones that have skin lesions that at one point in their development have an urticaria-like appearance or on rare occasion may have such lesions. These latter diseases are numerous, and we have tried to highlight the ones that most mimic chronic idiopathic urticaria or are more common.

CONCLUSIONS

A working knowledge of the diseases that can present with urticarial lesions is essential to accurately diagnose and effectively treat these symptomatic and sometimes serious conditions.

EAACI/GA2LEN/EDF guideline: definition, classification and diagnosis of urticaria

This guideline is the result of a consensus reached during a panel discussion at the 2nd International Consensus Meeting on Urticaria, Urticaria 2004, a joint initiative of the European Academy of Allergology and Clinical Immunology Dermatology Section and the European Union (EU)-funded network of excellence, GA2LEN. It covers the definition and classification of urticaria, taking into account the recent progress in identifying causes, eliciting factors and pathomechanisms of this disease. We have outlined useful diagnostic approaches for different subtypes of urticaria. This guideline was, in addition, accepted by the European Dermatology Forum (EDF) and was formally approved by the European Union of Medical Specialists (UEMS).

Bullous delayed pressure urticaria: pathogenic role for eosinophilic granulocytes?

Bullous delayed pressure urticaria (DPU) is a rare variant of DPU. Treatment of DPU is difficult and the underlying pathogenic mechanism of DPU remains elusive. We report a 72-year-old man with DPU and associated chronic urticaria as well as delayed urticarial dermographism. Pressure challenge gave rise to a deep weal covered by multiple vesicles and bullae after 24 h. Histological examination of a skin biopsy specimen obtained 24 h after pressure challenge demonstrated intraepidermal bullae filled with eosinophils accompanied by a dense, predominantly eosinophilic infiltrate in the dermis. Whereas the numbers and morphology of mast cells were unaltered, the extracellular deposition of eosinophil cationic protein revealed evidence for eosinophil activation. Concomitantly, both CD4+ and CD8+ T lymphocytes were present in the infiltrate and expressed interleukin 5. As bullous DPU may represent the maximal variant of DPU, the investigation of the cellular infiltrate and the chemokines/cytokines released may reveal potential pathogenic mechanisms. A possible effector role of eosinophilic granulocytes, T-cell subsets and mast cells is discussed.

Autoimmune urticaria

A growing body of evidence shows that at least 40% of patients with unexplained (idiopathic) chronic urticaria have clinically relevant functional autoantibodies to the high-affinity IgE receptor on basophils and mast cells. The term "autoimmune urticaria" is used for this subgroup of patients presenting with continuous ordinary urticaria. This article reviews the evidence for the autoimmune hypothesis and other nonantibody serum histamine-releasing factors in the etiopathogenesis of urticaria; defines autoimmune urticaria; looks at how autoimmune urticaria fits into existing classifications of urticaria; proposes diagnostic criteria that may be useful to the clinician; and reviews the management implications for patients with this subset of chronic disease.

Delayed pressure urticaria

Delayed pressure urticaria is a mechanical urticaria in which pressure causes whealing. Delayed cutaneous erythema and edema occur in association with marked subcutaneous swelling after the application of a sustained pressure stimulus to the skin. The earliest reports and theories of the pathogenesis of delayed pressure urticaria are summarized. Detailed attention is given to making the diagnosis by taking a history and provoking the lesions. The clinical features and natural history are considered. The effects of the disorder on quality of life are delineated, and management strategies are suggested.

Urticaria

Urticaria has been known as a disease since antiquity. However, in the last decades an increasing understanding of the mechanisms involved in its pathogenesis has shown the high heterogeneity of different urticaria subtypes. Clear distinction of the subtypes is required not only to choose the correct measures in diagnosis and management, but also to interpret the available data in research. The subtypes can be grouped into spontaneous urticaria, which includes acute urticaria and chronic urticaria, the physical urticarias, special types of urticaria including, e.g. contact urticaria, and diseases related to urticaria for historical reasons, e.g. urticaria pigmentosa. Most urticaria subtypes have a profound impact on the quality of life and effective treatment is thus required in case the diagnostic procedures do not reveal a cause which can be treated. Although, for symptomatic relief, nonsedating H1-antihistamines are the first choice in most subtypes of urticaria, double-blind controlled studies have shown that dosages required may exceed those recommended for other diseases, e.g. allergic rhinitis. Alternative treatments should be reserved for unresponsive patients.

Efficacy and safety of desloratadine 5 mg once daily in the treatment of chronic idiopathic urticaria: a double-blind, randomized, placebo-controlled trial

BACKGROUND

Chronic idiopathic urticaria (CIU) has a major impact on patient well-being. Antihistamines are the first-line treatment for CIU; however, some cause sedation.

OBJECTIVE

Our purpose was to study the efficacy and safety of desloratadine, 5 mg, a new H(1)-receptor antagonist, in patients with moderate to severe CIU.

METHODS

This study was a randomized, double-blind, placebo-controlled, parallel-group, multicenter trial of 6 weeks' duration.

RESULTS

Compared with placebo, desloratadine significantly improved the total CIU symptom score as well as pruritus, the number of hives, and the size of the largest hive. Overall therapeutic response and global CIU status improved significantly with desloratadine; interference with sleep was reduced and the performance of daily activities improved. Statistically and clinically significant improvements were seen within the first 24 hours of treatment and were sustained throughout the full duration of the study. The incidence of adverse events, including somnolence, was similar in the desloratadine and placebo groups.

CONCLUSION

Desloratadine is a well-tolerated and effective treatment of CIU.

Fexofenadine in chronic idiopathic urticaria: a clinical and immunohistochemical evaluation

Fexofenadine is a non-sedating selective third-generation antihistamine, which also exerts an anti-inflammatory action. The aim of this study was to evaluate the influence on the expression of inflammatory skin mediators, together with the efficacy and tolerability, of fexofenadine in chronic idiopathic urticaria (CIU). Fexofenadine 180mg was administered once daily for 4 weeks after a placebo run-in phase of 3 to 7 days. Efficacy paramaters were obtained from patients' assessment of urticaria symptoms. Non-lesional skin of patients with active CIU was studied immunohistochemically before and after treatment. The expression of the following mediators was evaluated: adhesion molecules (ICAM-1, ELAM-1, VCAM-1); mast cell proteases (chymase and tryptase) and proinflammatory cytokines (IL-1beta, IL-3, IL-6 and TNF-alpha). Of the 20 subjects enrolled, 3 dropped out of the study. Treatment proved successful in most cases (88.2%) (p <0.01) and a significant improvement of all symptoms was registered. Treatment was well-tolerated by all patients; adverse events, neither serious nor drug-related, occurred in any case. Immunochemistry revealed at the baseline a significant expression of ELAM-1, VCAM-1, tryptase, chymase, and TNF-alpha (p= 0.05) in non-lesional skin of patients compared to normal controls. After treatment with fexofenadine, there was a significant decrease in the expression of ELAM-1 (p= 0.02), VCAM-1 (p= 0.04) and tryptase (p= 0.04), whereas no relevant change was observed for the other parameters examined. This work confirms the efficacy and tolerability of fexofenadine HCl 180mg in CIU. These preliminary data show a trend towards a decrease in the expression of tryptase and some adhesion molecules after treatment, suggesting an anti-inflammatory activity of fexofenadine.

Evaluation of inflammatory parameters in physical urticarias and effects of an anti-inflammatory/antiallergic treatment

BACKGROUND

Physical urticaria (PU) includes a heterogeneous group of urticarias whose etiopathogenic aspects are still obscure and whose therapeutical management is often difficult. We have previously demonstrated the efficacy of a sequential treatment with nimesulide, a unique nonsteroidal anti-inflammatory drug, and ketotifen in various forms of PU.

METHODS

The expression of some inflammatory parameters was evaluated in 10 patients affected with some forms of PU. In particular, serum levels of interleukin (IL)-4, IL-1beta, tumor necrosis factor (TNF)-alpha, adhesion molecules (sELAM, sICAM-1 and sVCAM), soluble receptors (sIL-2R, sCD30, sCD23) and IgE were assessed. Moreover, the cutaneous expression of IL-1beta, TNF-alpha and ICAM-1 was studied on biopsy specimens taken from nonlesional skin of patients. The same parameters were further evaluated in both skin and serum following treatment with nimesulide and ketotifen, in order to better understand the possible effects of these agents on the inflammatory network of PU.

RESULTS

Before therapy we could detect significantly higher serum levels of IL-1beta and TNF-alpha (P < 0.001) and of circulating adhesion molecules in comparison with controls (sELAM, sICAM: P < 0.001; sVCAM: P < 0.02); after treatment, a significant reduction of each was observed (P < 0.05). Simultaneously, a high expression of IL-1beta, TNF-alpha and ICAM-1 was detected in all skin specimens at the baseline, with a relevant decrease following therapy.

CONCLUSIONS

These results confirm the therapeutical value of treatment with nimesulide and ketotifen in PU and suggest that these agents are able to reduce the release and the expression of some inflammatory molecules that are up-regulated in PU.

Delayed pressure urticaria

Delayed pressure urticaria is a physical urticaria where erythematous, often painful swellings occur at sites of sustained pressure on the skin, after a delay of several hours. If sought, it is present in up to 40% of patients with ordinary chronic "idiopathic urticaria" to a varying degree. Compared with other urticarias, the pressure-induced lesions impair the quality of life of patients most severely. The pathogenesis is not well characterized, but whealing is dependent on mast cell activation, with the histology of lesions also showing a deep dermal inflammatory infiltrate of neutrophils and eosinophils, without vasculitis. Treatment of delayed pressure is generally unsatisfactory, and is often resistant to antihistamine and a range of anti-inflammatory medication. Oral steroids, although the most effective therapy, are unsuitable for long-term use. Delayed pressure urticaria may persist for many years, and improved or novel methods of management are under investigation.

Definition, classification, and routine diagnosis of urticaria: a consensus report

Urticaria is a well-known disease entity; however, with an increasing understanding of the molecular mechanisms involved in its pathogenesis, there is also growing evidence for a heterogeneity of urticaria. Currently it is sometimes difficult to compare divergent data reported by different centers researching urticaria due to a lack of precisely described patient populations. A consensus definition and classification of the disease and its subtypes, taking into account new developments, are therefore needed. In addition, this consensus report provides a guideline for diagnostic procedures in different subtypes of urticaria.

Adhesion molecules and cellular infiltrate: histology of urticaria

Urticarial reactions are characterized by dermal capillary dilatation and edema, associated with a variably intense mixed inflammatory infiltrate consisting of neutrophils, eosinophils, T-helper lymphocytes, and activated macrophages. Mast cell numbers are moderately increased by a factor of 2.4, in contrast to mastocytosis where numbers are much higher (5-48-fold increase). In urticarial vasculitis there is in addition endothelial damage, leukocytoclasia, and fibrin and complement deposition. The emigration of leukocytes is regulated by vasoactive and chemotactic mediators released firom mast cells, inducing a sequential upregulation of endothelial adhesion molecules (P-selectin, E-selectin, ICAM-1, and VCAM-1), of beta2-integrins on leukocytes, and of cytokines on endothelial, epithelial, and infiltrating cells. In nonlesional skin, there is also an increase of mast cells and an upregulation of endothelial adhesion molecules, probably due to molecules in the circulation of which P-selectin and TNFalpha have so far been demonstrated. Whereas these data provide a molecular basis for the understanding of variations in mast cell-dependent pathology, they underline the fact that they are not diagnostic for different types of urticaria, except for urticarial vasculitis and mastocytosis.

Upregulation of TNF-alpha and IL-3 expression in lesional and uninvolved skin in different types of urticaria

BACKGROUND

Although mast cells are known to secrete a broad spectrum of proinflammatory and immunomodulatory cytokines, the role of these molecules in mast cell-dependent cutaneous inflammation is not clear.

OBJECTIVE

We decided to study biopsy specimens from lesional and nonlesional skin of patients with acute, chronic recurrent, delayed pressure, and cold urticaria; from fleeting wheals of prick test reactions to allergens; and from normal skin of nonallergic subjects.

METHODS

Cryostat sections were stained by immunohistochemistry with antibodies against IL-3, IL-8, TNF-alpha, and mast cell-specific tryptase. In serial sections with tryptase and each cytokine, reactivity of mast cells was studied as well.

RESULTS

Compared with normal skin and prick test reactions, immunoreactivity for TNF-alpha and IL-3 was significantly increased on endothelial and perivascular cells of the upper dermis in all urticaria lesions. In nonlesional skin comparable upregulation was noted on endothelial cells and for TNF-alpha on perivascular cells of patients with delayed pressure urticaria. In addition, TNF-alpha was expressed throughout the epidermis in lesional and nonlesional skin of patients with all types of urticaria, but not in normal control subjects. Sequential biopsy specimens from patients with cold urticaria showed upregulation of TNF-alpha and IL-3 on endothelial cells 30 minutes after elicitation of lesions with an ice cube. In contrast to these findings, epidermal immunoreactivity, as well as endothelial and perivascular cell expression of IL-8, were only slightly altered in urticaria compared with normal skin. In sequentially stained sections, few tryptase-positive mast cells reacted to TNF-alpha, few reacted to IL-3 in pressure urticaria only, and practically none stained for IL-8.

CONCLUSION

These findings suggest that the cytokines studied here are involved in the pathology of urticaria, possibly by inducing subthreshold inflammation in endothelial cells of uninvolved skin.

Cutaneous responses to substance P and calcitonin gene-related peptide in chronic urticaria: the effect of cetirizine and dimethindene

BACKGROUND

Neuropeptides appear to participate in the pathogenesis of chronic urticaria. The purpose of this study was to investigate the cutaneous responses to substance P (SP) and calcitonin gene-related peptide (CGRP) in delayed pressure urticaria patients (DPUpt) and chronic idiopathic urticaria patients (CIUpt) compared to healthy adults (HA), and also to evaluate the effect of H1-antagonists on these responses.

METHODS

Wheal (W) and flare (F) reactions to intradermally (ID) injected SP, CGRP, histamine (H), and diluent controls were evaluated in nine CIUpt, nine DPUpt, and nine HA at 3, 7, 15, 30, 60, and 120 min after injection. Maximal W and F, area under curve (AUC), and time of W and F disappearance were calculated at baseline and 4 h after a single dose of 20 mg cetirizine (Ce), 4 mg dimethindene (Di), or placebo (P), in a double-blind, placebo-controlled (DBPC), crossover, randomized study.

RESULTS

CIUpt exhibited enhanced and longer lasting W reactions to SP and CGRP (AUC: P<0.05) than HA; SP- and CGRP-induced F (at maximal concentration) were larger and longer lasting in CIUpt than in HA (P<0.003 and P = 0.004, respectively). In the DPU group, SP-induced W and F responses were intermediate in magnitude compared to CIUpt and HA. In HA, SP-induced flares were significantly suppressed only by Ce (P<0.020), while both Ce and Di affected SP-induced W and F in the two patient groups (P<0.05). CGRP-induced flare inhibition by the two H1-antagonists was also greater in the urticaria patient groups than in HA.

CONCLUSIONS

CIUpt and, to a lesser extent, DPUpt showed enhanced SP- and CGRP-induced W and F reactions. CGRP elicited an immediate W and F response, followed by prolonged erythema. H1-antagonists partially affected W and F reactions to SP and only the F response induced by CGRP; this effect was more pronounced in the urticaria patient groups than in HA. Overall, W and F cutaneous responses to SP were suppressed to a greater extent by Ce than Di.

Differential expression of cell adhesion molecules in inflamed appendix: correlation with clinical stage

The diagnosis of 'early inflamed', 'recurrent' or 'sub-acute' appendicitis is often difficult and accompanied by controversies between clinical data, histological findings, and their interpretation. The expression of the intercellular cell adhesion molecule-1 (ICAM-1), the vascular cell adhesion molecule-1 (VCAM-1), and E-selectin has been studied in 61 appendicectomy specimens for possible use as a diagnostic tool. This study demonstrates a different expression of CAM by endothelial (EC) and mesothelial cells (MC) in the various stages of appendicitis, with early E-selectin and ICAM-1 expression in EC, followed by VCAM-1 in EC and MC. Appendices from patients with prolonged clinical symptoms defined by clinicians as 'chronic' appendicitis showed VCAM-1 expression and occasionally weak expression of E-selectin in EC. In several cases, discrepancies were found between the pre-operative 'clinical' diagnosis, the histomorphological findings, and the immunohistological results. In this context, the expression of E-selectin and VCAM-1 in comparison with the histological features has potential significance in the diagnosis of 'early acute', 'sub-acute' or 'recurrent' appendicitis. In addition, a correlation was demonstrated between the histological stages of appendicitis and the kinetics of CAM expression. The study also indicates that the time course of E-selectin expression in vivo is longer than is suggested from in vitro data.