The cutaneous lesions of Kikuchi's disease: a comprehensive analysis of 16 cases based on the clinicopathologic, immunohistochemical, and immunofluorescence studies with an emphasis on the differential diagnosis

Kikuchi-Fujimoto disease: A comprehensive review

Kikuchi-Fujimoto disease, a rare form of necrotizing lymphadenitis, is an uncommon, benign, self-limiting disorder of obscure etiology. It affects mostly young adults of both genders. Clinically, it presents with fever and lymphadenopathy of a firm to rubbery consistency frequently involving cervical lymph nodes while weight loss, splenomegaly, leucopenia, and elevated erythrocyte sedimentation rate feature in severely affected patients. Cutaneous involvement occurs in about 30%-40% of cases as facial erythema and nonspecific erythematous papules, plaques, acneiform or morbilliform lesions of great histologic heterogeneity. Both Kikuchi-Fujimoto disease and systemic lupus erythematosus share an obscure and complex relationship as systemic lupus erythematosus may occasionally precede, develop subsequently, or sometimes be associated concurrently with Kikuchi-Fujimoto disease. It is often mistaken for non-Hodgkin lymphoma while lupus lymphadenitis, cat-scratch disease, Sweet’s syndrome, Still’s disease, drug eruptions, infectious mononucleosis, and viral or tubercular lymphadenitis are other common differentials. Fine needle aspiration cytology mostly has features of nonspecific reactive lymphadenitis and immunohistochemistry studies usually show variable features of uncertain diagnostic value. Since its diagnosis is exclusively from histopathology, it needs to be evaluated more carefully; an early lymph node biopsy will obviate the need for unnecessary investigations and therapeutic trials. Its treatment with systemic corticosteroids, hydroxychloroquine, or antimicrobial agents mostly remains empirical. The article reviews clinicoepidemiological, diagnostic, and management aspects of KFD from the perspective of practicing clinicians.

Kikuchi–Fujimoto disease: literature review and report of four cases

Kikuchi–Fujimoto disease, or necrotizing histiocytic lymphadenitis, is one of the rare causes of benign lymphadeno-pathy. The diagnosis is based on histological and immunohistochemical analysis of the lymph node biopsy. The article presents four clinical cases of Kikuchi–Fujimoto disease. According to the results of the primary analysis of lymph node tissue three patients were misdiagnosed with lymphoma. due to the unusual for lymphoid malignancy course the primary material was reviewed. The diagnosis of Kikuchi–Fujimoto disease was put. In three patients the disease has a re-current course. during the observation period, the course of the disease in all the presented patients is benign with normal quality of life.

Kikuchi-Fujimoto disease in the Eastern Mediterranean zone

Kikuchi–Fujimoto disease (KFD) is a rare benign and self-limiting syndrome. We aim to review cases of KFD at our institution as a rare illness in the Arab ethnic descent and to analyse reports from most countries in the East Mediterranean zone. This is a retrospective study in which the histopathology database was searched for the diagnosis of KFD. A full review of KFD patients’ medical records was done. Data regarding demographic features, clinical presentation, laboratory findings, comorbidities, and management protocols were obtained. Published KFD cases from east Mediterranean countries were discussed and compared to other parts of the world. Out of 1968 lymph node biopsies studied, 11 (0.6%) cases of KFD were identified. The mean age of patients with KFD was 32 years (4–59). 73% (8/11) were females. The disease was self-limiting in 5 patients (45%); corticosteroid therapy was needed in 4 patients (34%). One patient was treated with methotrexate and one with antibiotics. One patient died as a consequence of lymphoma. Jordanians and Mediterranean populations, especially those of Arab ethnic background, seem to have low rates of KFD. The genetic susceptibility theory may help to explain the significantly higher disease prevalence among East Asians. Early diagnosis of KFD—although challenging—is essential to reduce the morbidity related to this illness.

Kikuchi-Fujimoto disease involving retroperitoneal lymph nodes: An uncommon presentation

Kikuchi-Fujimoto disease is a self-limited disease of unknown etiology that is clinically defined by fevers accompanied by tender posterior cervical lymphadenopathy. It often presents acutely or sub-acutely, and due to its non-specific features, the differential diagnosis is broad and includes infectious, autoimmune, and malignant causes. Although cases of extra-cervical disease are not uncommon, involvement of retroperitoneal lymph nodes has only rarely been reported. Here, we describe a patient with Kikuchi-Fujimoto disease who presented with fever of unknown origin, abdominal pain, and enlarged hypermetabolic retroperitoneal lymph nodes.

Coincident Kikuchi-Fujimoto's disease and adult-onset Still's disease: report of a patient from an uncommonly affected population and case-directed systematic review

Kikuchi-Fujimoto's disease (KFD) and adult-onset Still's disease (AOSD) are rare idiopathic inflammatory conditions of unknown etiology. Ten prior instances of KFD and AOSD occurring together have been reported in the medical literature. These overlaps, together with certain distinguishing clinical and laboratory characteristics in these co-occurrences, offer insight into the pathophysiology of both of these rare disorders. Too, examination of these cases may help improve the diagnostic evaluation and care of patients afflicted with these rare diseases. We therefore report an additional patient with KFD and AOSD occurring in a middle-aged Hispanic female patient and perform a systematic literature review using the PubMed/MEDLINE and Embase databases to further analyze and compare prior identified cases. Our observations in our index case complement and expand previous reports, including new demographic and diagnostic features not seen in prior cases of overlap. Indeed ours is the first in a patient of Hispanic ethnicity, with retroperitoneal lymphadenopathy, as well as with a skin biopsy consistent with AOSD. Each of the reviewed cases of co-occurrence met the diagnostic criteria for both KFD and AOSD. This finding, in the setting of unique clinical and diagnostic manifestations that are not typically seen in either disease entity alone, suggests the presence of an overlap syndrome. Also, many of the shared clinical features and symptomatic responses to targeted therapies implies a similar, yet still poorly understood, pathophysiologic pathway for the two diseases.

Kikuchi-Fujimoto Disease Triggered by Systemic Lupus Erythematosus and Mycoplasma pneumoniae Infection-A Report of a Case and a Review of the Literature

ABSTRACT

Kikuchi-Fujimoto disease (KFD) is a necrotizing histiocytic lymphadenitis that was described for the first time in 1972 in Japan. Its etiology is still not fully understood. It has been reported in association with many different agents, diseases, and triggering factors without any conclusive result. To the best of our knowledge, we report for the first time a case of KFD with systemic lupus erythematosus in a child in association with a polymerase chain reaction (PCR)-positive throat swab for Mycoplasma pneumoniae. Although difficult to prove, the acute M. pneumoniae infection might have served as a triggering event for the development of KFD in our case. We encourage further studies to investigate a potential relationship between KFD and M. pneumoniae, which should also use PCR-based testing for this pathogen in patients with KFD.

Cutaneous Kikuchi disease-like inflammatory pattern without lymph node involvement is associated with systemic disease and severe features in lupus erythematous: A case-control study

INTRODUCTION

Kikuchi-Fujimoto disease (KFD) is a self-limited histiocytic necrotizing lymphadenitis sometimes affecting the skin. "Kikuchi disease-like inflammatory pattern" (KLIP) has been described in cutaneous lesions as similar pathological features in patients without lymph node involvement and as a potential clue for the diagnosis of lupus. We aimed to describe KLIP-associated clinical and immunological features in lupus patients with a retrospective case-control study.

METHODS

Thirteen cases of KLIP were included as well as thirty-nine age- and sex-matched control lupus patients without KLIP. At the time of KLIP diagnosis, 4/13 patients (31%) had isolated cutaneous lupus erythematosus (CLE) and 9/13 had (69%) systemic lupus erythematosus (SLE) including 6 (46%) with severe haematological, lung, cardiac or renal disease. KLIP features were observed in skin biopsies of different clinical presentations.

RESULTS

Compared with our control group, KLIP patients more frequently had SLE 9/13 (69%) versus 8/39 (21%) (OR 12.9; IC95% [2.86-58.2]; p = 0.0004) and more frequently severe SLE. Two out of four CLE exhibiting KLIP lesions (50%) developed severe SLE with cardiac or renal involvement after 12 and 24 months, respectively.Treatment with thalidomide 100 mg/day allowed rapid and complete clearance of cutaneous lesions in 6/6 KLIP patients. The need to use thalidomide tended to be more frequent in KLIP patients than in controls.

CONCLUSION

Our study suggests that KLIP features in lupus skin lesions are associated with SLE and severe systemic features. Despite a limited number of isolated CLE patients with KLIP features in the skin, this observation may warrant closer follow-up on patients with a higher risk of developing SLE.

A Case of Kikuchi-Fujimoto Disease Associated with Erosive Lichen Planus

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a benign, self-limiting disorder with unknown etiology. The most frequent clinical manifestations include lymphadenopathy, fever, cutaneous lesions, arthritis, fatigue, and hepatosplenomegaly. Cutaneous manifestations of KFD, occurring in about one-third of patients, are typically non-specific, rarely presenting as symmetrically distributed lesions. The prevalence of erosive lichen planus in patients with KFD, as of this date, is unknown with no previously reported cases describing an association between the two conditions. In the following case report, we report a case presenting with bilateral symmetrical erosive lichen planus of the heel associated with KFD as being a possible, rather novel, cutaneous manifestation.

A Challenging Case of Kikuchi-Fujimoto Disease Associated with Systemic Lupus Erythematosus and Review of the Literature

Kikuchi–Fujimoto disease (KFD) or histiocytic necrotizing lymphadenitis is a rare disease that is frequently underdiagnosed due to clinical features that are similar to those of non-Hodgkin lymphomas, systemic lupus erythematosus (SLE), or infectious reactive lymphadenopathy. An excisional biopsy is required. We report a young Caucasian female diagnosed with KFD with skin lesions, complicating with SLE. The clinical course, laboratory, and CT findings are described, as are histopathologic features, for a better recognition of this rare disorder in clinical practice.

Kikuchi-Fujimoto disease: a diagnostic dilemma

Kikuchi-Fujimoto disease is a benign, self-limiting condition characterized by lymphadenopathy and fever. Its diagnosis can be challenging, as the disease must be differentiated from lymphoma and systemic lupus erythematosus. Patients can present with nonspecific cutaneous lesions. Adequate clinical and histopathologic correlation can aid in the timely diagnosis of Kikuchi's disease, thus preventing the use of unnecessary diagnostic procedures and inappropriate treatments.

Kikuchi Disease-Like Inflammatory Pattern in Cutaneous Inflammatory Infiltrates Without Lymph Node Involvement: A New Clue for the Diagnosis of Lupus?

Kikuchi-Fujimoto disease (KFD) is a rare and benign disorder that usually occurs in young adults with enlarged lymph nodes containing infiltrate of cytotoxic T cells and nuclear debris. It can be a manifestation of systemic lupus erythematosus (SLE) although the strength of this association has varied among studies. Although specific KFD cutaneous lesions are well described, pure cutaneous lesions have never been reported. We studied a series of patients prospectively entered into a database between 2007 and 2014 with skin biopsies showing diffuse or localized inflammatory infiltrates reminiscent of cutaneous KFD, without lymph-node-related KFD. We called these skin lesions "Kikuchi disease-like inflammatory pattern" (KLIP). Twenty-nine patients, whose median age was 49 years at the time of skin biopsy, were selected and retrospectively analyzed using standardized clinical and histology charts. In skin biopsies, KLIP was localized to restricted areas within the inflammatory infiltrate (17%) or diffuse (83%), and was the only histological finding (45%) or accompanied interface dermatitis with or without dermal mucinosis (55%). Clinical dermatological findings varied widely. A definite diagnosis could be established for 24 patients: 75% had connective tissue diseases or vasculitis, mainly cutaneous lupus erythematosus (CLE) (n = 16, 67%), including 5 SLE with satisfying American College of Rheumatology criteria; 3 of the remaining patients had malignant hemopathies. CLE patients were mostly young females with acute (n = 5), subacute (n = 4), or chronic CLE (n = 6) or lupus tumidus (n = 1). Two were classified as having anti-tumor necrosis factor-alpha-induced lupus. Because two-thirds of these patients were finally diagnosed with CLE, we think that KLIP may represent a new histopathological clue for the diagnosis of lupus based on skin biopsy, requiring clinical-immunological comparison to make the correct diagnosis. KLIP should not be considered a variant of classical KFD, but rather as an elementary pattern of cutaneous inflammation, that might be the expression of the same cytotoxic process within skin infiltrates as that involved in KFD. This lesion might reflect a particular T-cell-mediated autoimmune process directed against mononuclear cells within cutaneous lupus infiltrates.

The pathologic findings of skin, lymph node, liver, and bone marrow in patients with adult-onset still disease: a comprehensive analysis of 40 cases

Adult-onset Still disease (AOSD) is characterized by fever, skin rash, and lymphadenopathy with leukocytosis and anemia as common laboratory findings. We investigated the characteristic pathologic findings of skin, lymph node, liver, and bone marrow to assist in proper diagnosis of AOSD.Forty AOSD patients were included in the study. The skin (26 patients), lymph node (8 patients), liver (8 patients), or bone marrow biopsies (22 patients) between 1998 and 2013 were retrospectively analyzed. AOSD patients were diagnosed according to the Yamaguchi criteria after excluding common infections, hematological and autoimmune diseases. Immunohistochemistry, immunofluorescence, and Epstein-Barr virus-encoded RNA (EBER) in situ hybridization were performed.Most skin biopsies revealed mild lymphocytic or histiocytic infiltration in the upper dermis. Nuclear debris was frequently found in the dermis in 14 cases (53.8%). More than half of the cases (n = 14, 53.8%) showed interstitial mucin deposition. Some cases showed interface dermatitis with keratinocyte necrosis or basal vacuolization (n = 10; 38.5%). The lymph node biopsies showed a paracortical or diffuse hyperplasia pattern with immunoblastic and vascular proliferation. The liver biopsies showed sparse portal and sinusoidal inflammatory cell infiltration. All cases showed various degrees of Kupffer cell hyperplasia. The cellularity of bone marrow varied from 20% to 80%. Myeloid cell hyperplasia was found in 14 out of the 22 cases (63.6%). On immunohistochemistry, the number of CD8-positive lymphocytes was greater than that of CD4-positive lymphocytes in the skin, liver, and bone marrow, but the number of CD4-positive lymphocytes was greater than that of CD8-positive lymphocytes in the lymph nodes.The relatively specific findings with respect to the cutaneous manifestation of AOSD were mild inflammatory cell infiltration in the upper dermis, basal vacuolization, keratinocyte necrosis, presence of karyorrhexis, and mucin in the dermis. In all cases, pathologic findings in the lymph nodes included paracortical hyperplasia with vascular and immunoblastic proliferation. Skin and lymph node pathology in addition to clinical findings can aid in the diagnosis of AOSD.

Kikuchi-Fujimoto disease: retrospective study of 91 cases and review of the literature

Kikuchi-Fujimoto disease (KFD) is a rare cause of lymphadenopathy, most often cervical. It has been mainly described in Asia. There are few data available on this disease in Europe. We conducted this retrospective, observational, multicenter study to describe KFD in France and to determine the characteristics of severe forms of the disease and forms associated with systemic lupus erythematosus (SLE). We included 91 cases of KFD, diagnosed between January 1989 and January 2011 in 13 French hospital centers (median age, 30 ± 10.4 yr; 77% female). The ethnic origins of the patients were European (33%), Afro-Caribbean (32%), North African (15.4%), and Asian (13%). Eighteen patients had a history of systemic disease, including 11 with SLE. Lymph node involvement was cervical (90%), often in the context of polyadenopathy (52%), and it was associated with hepatomegaly and splenomegaly in 14.8% of cases. Deeper sites of involvement were noted in 18% of cases. Constitutional signs consisted mainly of fever (67%), asthenia (74.4%), and weight loss (51.2%). Other manifestations included skin rash (32.9%), arthromyalgia (34.1%), 2 cases of aseptic meningitis, and 3 cases of hemophagocytic lymphohistiocytosis. Biological signs included lymphocytopenia (63.8%) and increase of acute phase reactants (56.4%). Antinuclear antibodies (ANAs) and anti-DNA antibodies were present in 45.2% and 18% of the patients sampled, respectively. Concomitant viral infection was detected in 8 patients (8.8%). Systemic corticosteroids were prescribed in 32% of cases, hydroxychloroquine in 17.6%, and intravenous immunoglobulin in 3 patients. The disease course was always favorable. Recurrence was observed in 21% of cases. In the 33 patients with ANA at diagnosis, SLE was known in 11 patients, diagnosed concomitantly in 10 cases and in the year following diagnosis in 2 cases; 6 patients did not have SLE, and 4 patients were lost to follow-up (median follow-up, 19 mo; range, 3-39 mo). The presence of weight loss, arthralgia, skin lesions, and ANA was associated with the development of SLE (p < 0.05). Male sex and lymphopenia were associated with severe forms of KFD (p < 0.05). KFD can occur in all populations, irrespective of ethnic origin. Deep forms are common. An association with SLE should be investigated. A prospective study is required to determine the risk factors for the development of SLE.

Kikuchi's disease of the xanthomathous type with cutaneous manifestations

Kikuchi's disease is a benign, self-limiting disease, whose pathogenesis remains unknown. Patients most often present with cervical lymphadenopathy, sometimes associated with fever and leukopenia. It has been reported that up to 40% of patients with Kikuchi's disease have also cutaneous eruptions, but no specific skin changes have been described. Kikuchi's disease can be subclassified into three histologic subtypes: a proliferative type, a necrotizing type and a xantomathous type. Most patients with Kikuchi's disease require no specific treatment, because the disease regresses spontaneously, within a few weeks to months. We report a case of a 31-year-old woman with xanthomatous type of Kikuchi's disease, whose first manifestation was the onset of erythematous papules with central suppuration on her face and on her left hand.

Epstein-Barr virus: dermatologic associations and implications: part I. Mucocutaneous manifestations of Epstein-Barr virus and nonmalignant disorders

Epstein-Barr virus (EBV) is a ubiquitous virus that has been implicated in a wide range of human diseases, many of which have mucocutaneous manifestations. As a member of the herpesviridae family, EBV causes lifelong infection by establishing latency in B lymphocytes. An intact immune response is critical in preventing progression of EBV disease, and the clinical manifestations of infection are dependent on the intricate relationship between virus and host immune system. This review provides a comprehensive overview of the epidemiology, pathophysiology, and diagnostic testing in EBV infection. In part I of this continuing medical education article, the mucocutaneous manifestations of EBV infection are reviewed with an emphasis on pathophysiology and management.

Kikuchi-Fujimoto disease: retrospective study of 91 cases and review of the literature

Kikuchi-Fujimoto disease (KFD) is a rare cause of lymphadenopathy, most often cervical. It has been mainly described in Asia. There are few data available on this disease in Europe. We conducted this retrospective, observational, multicenter study to describe KFD in France and to determine the characteristics of severe forms of the disease and forms associated with systemic lupus erythematosus (SLE). We included 91 cases of KFD, diagnosed between January 1989 and January 2011 in 13 French hospital centers (median age, 30 ± 10.4 yr; 77% female). The ethnic origins of the patients were European (33%), Afro-Caribbean (32%), North African (15.4%), and Asian (13%). Eighteen patients had a history of systemic disease, including 11 with SLE. Lymph node involvement was cervical (90%), often in the context of polyadenopathy (52%), and it was associated with hepatomegaly and splenomegaly in 14.8% of cases. Deeper sites of involvement were noted in 18% of cases. Constitutional signs consisted mainly of fever (67%), asthenia (74.4%), and weight loss (51.2%). Other manifestations included skin rash (32.9%), arthromyalgia (34.1%), 2 cases of aseptic meningitis, and 3 cases of hemophagocytic lymphohistiocytosis. Biological signs included lymphocytopenia (63.8%) and increase of acute phase reactants (56.4%). Antinuclear antibodies (ANAs) and anti-DNA antibodies were present in 45.2% and 18% of the patients sampled, respectively. Concomitant viral infection was detected in 8 patients (8.8%). Systemic corticosteroids were prescribed in 32% of cases, hydroxychloroquine in 17.6%, and intravenous immunoglobulin in 3 patients. The disease course was always favorable. Recurrence was observed in 21% of cases. In the 33 patients with ANA at diagnosis, SLE was known in 11 patients, diagnosed concomitantly in 10 cases and in the year following diagnosis in 2 cases; 6 patients did not have SLE, and 4 patients were lost to follow-up (median follow-up, 19 mo; range, 3-39 mo). The presence of weight loss, arthralgia, skin lesions, and ANA was associated with the development of SLE (p < 0.05). Male sex and lymphopenia were associated with severe forms of KFD (p < 0.05). KFD can occur in all populations, irrespective of ethnic origin. Deep forms are common. An association with SLE should be investigated. A prospective study is required to determine the risk factors for the development of SLE.

Co-occurrence of Kikuchi-Fujimoto's disease and Still's disease: case report and review of previously reported cases

Kikuchi-Fujimoto's disease (KFD) and adult-onset Still's disease (AOSD) are rare inflammatory conditions with some overlapping features. We encountered a 22-year-old male patient who presented with daily fevers, neck discomfort, and sore throat and subsequently developed rash, arthritis, and cervical lymphadenopathy. Biopsy of the skin rash was consistent with KFD skin involvement. Given that the patient also met criteria for AOSD, a final diagnosis of KFD/AOSD co-occurrence was made. Anti-IL-1β therapy with anakinra resulted in rapid resolution of all symptoms. A literature search identified eight more cases of KFD/AOSD. Fever, rash, arthritis, and lymphadenopathy were present in all patients. No case report demonstrated an association of rash eruption clearly associated with fever spikes. Duration of symptoms ranged from 3 weeks to 10 years. Seven patients had leukocytosis, six had anemia, and five demonstrated elevated ferritin and/or decreased glycosylated ferritin. Seven patients had elevated erythrocyte sedimentation rate (ESR), and seven had transaminitis. Eight of nine patients had no evidence of infectious disease. Autoantibodies were absent from all patients. KFD and AOSD are very rare diseases, yet they may overlap. The two conditions not only share several clinical and laboratory characteristics but also differ in characteristic ways. Given the rapid response observed with anakinra in the index patient, IL-1β likely plays a role in both diseases.

Characteristics of Kikuchi-Fujimoto disease in children compared with adults

Kikuchi-Fujimoto disease (KFD) is a benign, self-limiting disease characterized by cervical lymphadenopathy. Although it was primarily thought to be a disease of young adults, it has been increasingly recognized in children. To define the characteristics of KFD in children, we reviewed the medical records of patients younger than 18 years of age who were diagnosed with KFD from 2001 to 2012 at Korea University Medical Center, as well as worldwide published reports of KFD. A total of 140 pediatric patients and 733 patients of all ages was analyzed. Compared to the female predominance found in adults (2:1), young boys were more commonly affected than young girls (1.4:1). Cervical lymphadenopathy was the most common clinical finding in children, as it was in adults. Lymphadenopathy was more likely to be tender (69 vs. 44 %, p < 0.001) but less generalized (1 vs. 8 %, p < 0.05) in children compared to adults. Fever (82 vs. 35 %, p < 0.001) and rash (10 vs. 4 %, p < 0.05) were observed in children more commonly than in adults. Leukopenia was observed in 50 and 38 % of children and adults, respectively. Rates of recurrence and association with autoimmune diseases in children were comparable to those of adults. Cervical lymphadenopathy was the most common clinical manifestation of KFD in all ages. While fever and rash were more common in children with KFD compared to adults, generalized lymphadenopathy was rarer.

Kikuchi disease with skin lesions mimicking lupus erythematosus

BACKGROUND

Kikuchi disease (Kikuchi-Fujimoto disease, histiocytic necrotizing lymphadenitis) is a systemic illness of unkown etiology. It is characterized by cervical lymphadenopathy and fever. The skin is the most frequently affected extranodal organ. Cuta-neous Kikuchi-Fujimoto disease can mimic both clinically and histolo-gically skin lesions in lupus erythema-tosus, a disorder with which it seems to be closely related. A close follow up is required as systemic lupus erythema-tosus develop-ment has been reported.

MAIN OBSERVATION

We report a case of a 23-year-old woman, who was admitted to our depart-ment with high fever, skin lesions and arthralgia. Scaly and erythematous plaques were noted on both cheeks and earlobes. In pads of feet and hands and periungual area, multiple purple papules with a perilesional erythematous halo were evident. A thoraco-abdominal computed tomography scan revealed lateral cervical, mediastinal, paratracheal, subcarinal and submandi-bular lympha-denopathy. Excisional node biopsy was consisten with Kikuchi disease with skin involvement.

CONCLUSION

It has to be kept in mind that Kikuchi disease is a differential diag-nosis in case of fever, lymphade-nopathy and lupus-like skin lesions. Skin lesions in this disease and may resemble clinically and histologically to those of subacute lupus erythema-tosus or systemic erythema-tosus lupus.

Current knowledge in inflammatory dermatopathology

The complex and fascinating spectrum of inflammatory skin disease, and the comprehension of it, is ever expanding and evolving. During the first decade of the 21st century, numerous advances in the understanding of inflammatory disease mechanisms have occurred, particularly in psoriasis and atopic dermatitis. Continuation of this trend will assure a future in which molecular tests for biomarkers of immediate clinical relevance are used in routine patient care, not only for diagnosis but also for prognosis and management. This article focuses on selected recent or noteworthy developments that are clinically relevant for the histologic diagnosis of inflammatory skin diseases.