Urticarial lesions: if not urticaria, what else? The differential diagnosis of urticaria: part II. Systemic diseases

Two case reports of skin vasculitis following the COVID-19 immunization

The coronavirus 2019 (COVID-19) disease is now responsible for one of the most challenging and concerning pandemics. Since December 2020, the world has had access to COVID-19 prophylaxis; thus, we encounter adverse events from vaccination more often due to the vast vaccination range. We present two case reports of difficult-to-treat skin vasculitis due to COVID-19 vaccination that were successfully treated in a tertiary-level university hospital. When encountering systemic treatment, resistant skin vasculitis plasmapheresis could be a choice of treatment.

Annular urticarial lesions

Annular urticarial configurations are often associated with acute and chronic urticaria. Such lesions may be short-lived, migratory, transient, pruritic, and resolving with no residual evidence, making the diagnosis of urticaria an obvious one. Annular urticarial lesions can be the presenting signs of various cutaneous and systemic diseases. The differentiation of urticarial lesions may be made by considering the duration of an individual lesion longer than 24 hours, with burning and pain sensation in the lesions or lack of pruritus; skin marks such as postinflammatory pigmentation or purpura after resolution of the lesions; associated scaling or vehiculation in the lesions; systemic symptoms such as arthralgia, fever or fatigue; and several abnormal laboratory findings. The main differential diagnoses of annular urticarial lesions include urticarial vasculitis, autoinflammatory syndromes, hypersensitivity reactions, and connective tissue diseases.

Differential Diagnosis of Urticarial Lesions

Urticaria is a mast cell-dependent disease, characterized by the presence of wheals, angioedema, or both in the absence of systemic symptoms. It is a common disease worldwide, with an important health burden especially in chronic situations, that last more than 6 weeks. Although urticaria is usually a straightforward diagnosis, some diseases presenting with urticarial lesions must be excluded, particularly urticarial vasculitis and auto-inflammatory syndromes. In these settings additional atypical features are often present (long-lasting lesions, bruising, fever, malaise, arthralgia), allowing the clinician to suspect a diagnosis other than urticaria. The authors propose an approach based on these atypical features, the presence or absence of systemic symptoms and on skin histopathology as well as some blood parameters.

Skin eruptions in children: Drug hypersensitivity vs viral exanthema

Childhood rashes or exanthemas are common and are usually relatively benign. There are many causes of rash in children, including mainly viruses, and less often bacterial toxins, drugs, allergens and other diseases. Viral exanthema often appears while children are taking a medication in the course of a viral infection; it can mimic drug exanthema and is perceived as a drug allergy in 10% of cases. In the vast majority of cases, the distinction between virus-induced and drug-induced skin eruption during the acute phase is not possible. The drugs most commonly implicated are beta-lactams (BL) and non-steroidal anti-inflammatory drugs (NSAIDs). Viruses, commonly Epstein-Barr virus (EBV), human herpesvirus 6 (HHV6) and cytomegalovirus (CMV), and the bacterium, Mycoplasma pneumoniae, may cause exanthema either from the infection itself (active or latent) or because of interaction with drugs that are taken simultaneously. Determination of the exact diagnosis requires a careful clinical history and thorough physical examination. Haematological and biochemical investigations and histology are not always helpful in differentiating between the two types of exanthema. Serological and polymerase chain reaction (PCR) assays can be helpful, although a concomitant acute infection does not exclude drug hypersensitivity. A drug provocation test (DPT) is although considered the gold standard for the diagnosis and is not preferred by the patients. Skin tests are not well tolerated, and in vitro tests, such as the basophil activation test and lymphocyte transformation, are of low sensitivity and specificity and their relevance is debatable. Based on current evidence, we propose a systematic clinical approach for timely differential diagnosis and management of rashes in children who present a cutaneous eruption while receiving a drug.

The Diagnostic Workup in Chronic Spontaneous Urticaria-What to Test and Why

BACKGROUND

In chronic spontaneous urticaria (CSU), the guidelines recommend very limited diagnostic procedures during the routine workup, although additional investigations might be indicated in some patients with CSU. For physicians treating patients with CSU, it is often difficult to decide which diagnostic tests are useful.

OBJECTIVE

To provide recommendations on what diagnostic tests should be performed on which patients with CSU.

METHODS

We performed an extensive literature search on the respective topics and identified relevant questions that should prompt diagnostic procedures based on the published evidence and expert consensus among all authors.

RESULTS

We provide questions, diagnostic testing, where appropriate, and recommendation that should be included when assessing the history of a patient with CSU, to explore and rule out differential diagnoses, to assess patients for underlying causes and modifying conditions, to explore patients for comorbid diseases and consequences of having CSU, and to assess patients for CSU components that can help to predict their disease course and response to treatment.

CONCLUSIONS

Here, we provide physicians treating patients with CSU with information about which clues should lead to which tests and why.

Histopathology of chronic spontaneous urticaria with occasional bruising lesions is not significantly different from urticaria with typical wheals

BACKGROUND

Chronic spontaneous urticaria (CSU) may occasionally exhibit long-lasting lesions with bruising, usually considered a hallmark of urticarial vasculitis (UV). Histopathology of these chronic urticarial lesions has not been extensively studied.

METHODS

Skin biopsies from patients with anti-H1 resistant CSU were evaluated for several parameters (edema, location, intensity, and cell composition of the inflammatory infiltrate, and abnormalities in the blood vessels).

RESULTS

We studied 45 patients (37 female/8 male, mean age 49.3 years) with CSU, 60% of whom with occasional bruising lesions and 3 patients with hypocomplementemic UV. Histopathology in CSU showed mainly perivascular and interstitial inflammatory infiltrate (91.1%), including eosinophils (80%), neutrophils (77.8%), and lymphocytes (71.1%), vasodilatation (88.9%), intravascular neutrophils (95.6%), dermal edema (51.1%), swelling of endothelial cells (51.1%), and minor and rare fibrinoid necrosis and karyorrhexis (6.7%). Significant karyorrhexis and frank fibrinoid necrosis were observed, respectively, in two and three cases of UV. In patients with occasional bruising, mast cells occurred in fewer cases whereas eosinophils were more frequent, but no statistically significant difference was found for other parameters.

CONCLUSIONS

Histopathological findings were not significantly different between CSU with or without bruising lesions. Bruising may be associated with more severe forms of CSU with no histopathological signature, although UV cannot be completely excluded based on histopathology.

Urticaria and angioedema as a prodromal cutaneous manifestation of SARS-CoV-2 (COVID-19) infection

This is a case of a patient who presented with an urticarial rash 48 hours before developing symptoms of fever and a continuous cough. She subsequently developed angioedema of her lips and hands before testing positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Urticarial rashes occurring 48 hours before other symptoms of COVID-19 infection have been documented. This case demonstrates the importance of heightened awareness that not all urticarial rashes represent spontaneous urticaria and as a consequence, this may result in misdiagnosis and ultimately delayed diagnosis. This is the first reported case in the literature of urticaria with angioedema as a prodromal phenomenon of COVID-19.

Update on vasculitis: overview and relevant dermatological aspects for the clinical and histopathological diagnosis - Part II

Vasculitis is a group of several clinical conditions in which the main histopathological finding is fibrinoid necrosis in the walls of blood vessels. This article assesses the main dermatological aspects relevant to the clinical and laboratory diagnosis of small- and medium-vessel cutaneous and systemic vasculitis syndromes. The most important aspects of treatment are also discussed.

Urticaria: recommendations from the Italian Society of Allergology, Asthma and Clinical Immunology and the Italian Society of Allergological, Occupational and Environmental Dermatology

BACKGROUND

Urticaria is a disorder affecting skin and mucosal tissues characterized by the occurrence of wheals, angioedema or both, the latter defining the urticaria-angioedema syndrome. It is estimated that 12-22% of the general population has suffered at least one subtype of urticaria during life, but only a small percentage (estimated at 7.6-16%) has acute urticaria, because it is usually self-limited and resolves spontaneously without requiring medical attention. This makes likely that its incidence is underestimated. The epidemiological data currently available on chronic urticaria in many cases are deeply discordant and not univocal, but a recent Italian study, based on the consultation of a national registry, reports a prevalence of chronic spontaneous urticaria of 0.02% to 0.4% and an incidence of 0.1-1.5 cases/1000 inhabitants/year.

METHODS

We reviewed the recent international guidelines about urticaria and we described a methodologic approach based on classification, pathophysiology, impact on quality of life, diagnosis and prognosis, differential diagnosis and management of all the types of urticaria.

CONCLUSIONS

The aim of the present document from the Italian Society of Allergology, Asthma and Clinical Immunology (SIAAIC) and the Italian Society of Allergological, Occupational and Environmental Dermatology (SIDAPA) is to provide updated information to all physicians involved in diagnosis and management of urticaria and angioedema.

Schnitzler syndrome

Schnitzler syndrome is a very rare acquired systemic disease with many similarities to hereditary autoinflammatory syndromes. The main characteristics are generalized exanthema and IgM monoclonal gammopathy. Other clinical features include fever, muscle, bone, and/or joint pain, and lymphadenopathy. About 15-20% of patients with Schnitzler syndrome develop lymphoproliferative diseases and, in rare cases, amyloid A (AA) amyloidosis can occur if the disease is not treated. Activation of the innate immune system, especially interleukin (IL)-1β, is central to the pathogenesis of disease. Consequently, complete control of disease symptoms can be achieved in 80% of patients by treatment with the IL-1 receptor antagonist anakinra.

Clinical Conditions that Masquerade as Urticaria

Chronic urticaria is one of the most commonly diagnosed dermatoses. Following diagnosis, correct identification and proper treatment significantly reduces disease activity, thereby improving the patient’s quality of life. However, there is an extensive differential diagnosis for chronic urticaria that, if missed, can lead to life-threatening sequelae. Many of the diseases that masquerade as urticaria are rare and often have a significant delay in diagnosis. This paper aims to fill the gap in the literature by clearly characterising the cutaneous eruptions and atypical findings in many of the most common mimickers of chronic urticaria. Conditions such as erythema marginatum seen in conjunction with hereditary angioedema, urticaria vasculitis, autoinflammatory cryopyrin-associated periodic syndromes, adult-onset Still’s disease and systemic onset juvenile arthritis, Schnitzler syndrome, erythema multiforme, and cutaneous mastocytosis will be discussed.

Urticaria in children and adolescents: An updated review of the pathogenesis and management

The present survey represents the latest data on diagnosis and management of childhood urticaria. It has been observed that urticaria occurs less often in children than adults, with symptoms rarely lasting for over 6 weeks. Triggers or aggravating factors can be found only in 21%-55% of cases. Finding autoantibodies in children does not impact a disease prognosis, unlike in adult patients, where the presence of autoantibodies is associated with a more prolonged run of the disease, a more severe prognosis and more intensive treatment methods. The incidence of food allergy equals to 8%-10% of cases. The incidence of Helicobacter Pylori infection in children is lower than that in adults and comes to 10%-18%. Medical experts recommend using the same treatment schemes for adults and children. This survey describes different urticaria management patterns suggested by experts from Europe, America, and Russia in their recent guidelines. It has been noted that unlike the guidelines from 2014, the 2018 clinical practice guidelines for the diagnosis and management of urticarial once again suggest a four-step treatment scheme with assigning omalizumab for Step 3 and cyclosporine A for Step 4 in the event of low therapeutic efficacy of the previous step or its impossibility. Leukotriene antagonists (LTRAs) are currently removed from basic management to alternative programs.

[Schnitzler syndrome]

Schnitzler syndrome is a very rare acquired systemic disease with many similarities to hereditary autoinflammatory syndromes. The main characteristics are generalized exanthema and a monoclonal gammopathy with IgM. Other clinical features include fever, muscle, bone and/or joint pain, and lymphadenopathy. About 15-20% of patients with Schnitzler syndrome develop lymphoproliferative diseases and, in rare cases, amyloid A (AA) amyloidosis can occur if the disease is not treated. Activation of the innate immune system, especially interleukin(IL)-1β, is central in the pathogenesis of the disease. Consequently, complete control of disease symptoms can be achieved in 80% of patients by treatment with the IL-1 receptor antagonist anakinra.

[Schnitzler syndrome]

Schnitzler syndrome is a very rare acquired systemic disease with many similarities to hereditary autoinflammatory syndromes. The main characteristics are generalized exanthema and a monoclonal gammopathy with IgM. Other clinical features include fever, muscle, bone and/or joint pain, and lymphadenopathy. About 15-20% of patients with Schnitzler syndrome develop lymphoproliferative diseases and, in rare cases, amyloid A (AA) amyloidosis can occur if the disease is not treated. Activation of the innate immune system, especially interleukin(IL)-1β, is central in the pathogenesis of the disease. Consequently, complete control of disease symptoms can be achieved in 80% of patients by treatment with the IL-1 receptor antagonist anakinra.

Urticarial Dermatitis: Clinical Characteristics of Itch and Therapeutic Response to Cyclosporine

Background

Urticarial dermatitis, which is characterised by persistent wheals with eczematous papules and plaques, is frequently misdiagnosed and difficult to treat. Patients commonly experience intolerable pruritus which may greatly affect their quality of life.

Objective

The objective of this study is to characterize the clinical patterns of pruritus in patients with urticarial dermatitis and to determine the effectiveness of cyclosporine treatment.

Methods

This prospective study included 50 histopathologically confirmed patients with urticarial dermatitis. A face-to-face structured questionnaire was given to all patients, and they were treated with low-dose cyclosporine (1~3 mg/kg/d) for at least 2 weeks.

Results

The majority of patients (80.0%) had moderate to severe pruritus. Most patients experienced exacerbation of the itch in the evening (74.0%), with the extremities (upper, 86.0%; lower, 94.0%) being the most commonly involved sites. Due to severe pruritus, patients complained about reduced social contact, quality of life and difficulties in falling asleep et al. Cyclosporine significantly reduced the mean itch score and extent of erythema, and improved interference with daily activities and sleep.

Conclusion

Our study highlights the detailed description and characteristics of pruritus in patients with urticarial dermatitis. And we recommend alternative and effective therapeutic option of low-dose cyclosporine.

Skin Biopsy, the Allergists' Tool: How to Interpret a Report

Inflammatory dermatoses are frequently encountered by the allergist, and histologic evaluation achieved through skin biopsy can be of tremendous value clinically. There is no substitute for a thorough history and physical exam; however, the skin biopsy is a simple, in-office procedure with little risk of complication that can provide invaluable information when a diagnosis is uncertain. Histopathologically, many inflammatory eruptions can look similar or overlap, but information provided by the dermatopathologist can help the clinician render or refine the clinical diagnosis and guide management. This review will discuss descriptive elements contained in the pathology report to provide a framework that can be used by the allergist to comfortably and confidently diagnose inflammatory dermatologic conditions.

Typical evanescent and atypical persistent polymorphic cutaneous rash in an adult Brazilian with Still's disease: a case report and review of the literature

Adult onset Still's disease (AOSD) is a systemic auto-inflammatory condition of unknown etiology, characterized by high fever, an evanescent, salmon-pink maculopapular skin rash, arthralgia or arthritis and leukocytosis. AOSD can also present with atypical cutaneous manifestations, such as persistent pruritic coalescent papules or plaques and linear lesions that have highly distinctive pathological features and are usually associated with severe disease. Herein, we present a 31-year-old Brazilian man with both typical Still's rash and atypical persistent polymorphic cutaneous manifestations associated with severe systemic inflammatory response syndrome. Eosinophils that are consistently lacking in the AOSD-associated skin lesions were evident in the skin biopsy of the persistent atypical cutaneous manifestations and were either drug-related or AOSD-associated.

Cutaneous lesions and finger clubbing uncovering hypocomplementemic urticarial vasculitis and hepatitis C with mixed cryoglobulinemia

Urticarial vasculitis is a rare clinicopathologic entity characterized by urticarial lesions that persist for more than 24 hours and histologic features of leukocytoclastic vasculitis. Patients can be divided into normocomplementemic or hypocomplementemic. The authors report the case of a healthy 49-year-old woman with a 1-year history of highly pruritic generalized cutaneous lesions and finger clubbing. Laboratory tests together with histopathologic examination allowed the diagnosis of hypocomplementemic urticarial vasculitis, chronic hepatitis C and type II mixed cryoglobulinemia. The patient started symptomatic treatment and was referred to a gastroenterologist for management of the hepatitis C, with progressive improvement of the skin condition. The development of hypocomplementemic urticarial vasculitis in the context of chronic hepatitis C is exceedingly rare and possible pathogenic mechanisms are discussed.

Cutaneous manifestations of adult-onset Still's disease: a case report and review of literature

Adult onset Still's disease (AOSD) is a systemic inflammatory disorder of unknown etiology and pathogenesis characterized by high spiking fever, arthralgia or arthritis, sore throat, lymphadenopathy, hepatosplenomegaly, serositis, and transient cutaneous manifestations. Although more common in children, cases are seen also in adults. Cutaneous involvement is common and may be suggestive for the diagnosis. A case of AOSD in a 35-year-old man is reported here, presenting with urticarial maculopapular rash of trunk, high spiking fever, acute respiratory distress syndrome, and myopericarditis. Skin biopsy showed interstitial and perivascular mature CD15(+) neutrophils. A comprehensive review of literature showed that cutaneous involvement occurs in about 80 % of patients, with various clinical presentations. The most common skin manifestation is an evanescent salmon pink or erythematous maculopapular exanthema, predominantly on the trunk and proximal limbs, with rare involvement of face and distal limbs. Less common manifestations include persistent erythematous plaques and pustular lesions. A constant histopathologic finding is the presence of interstitial dermal neutrophils aligned between the collagen bundles. This pattern may provide an easy accessible clue for the definitive diagnosis of AOSD and exclude other diagnosis such as drug eruptions or infectious diseases.

Cutaneous drug reactions in the pediatric population

Cutaneous adverse drug reactions (ADRs) constitute a major pediatric health problem frequently encountered in clinical practice, and represent a diagnostic challenge. Children are more susceptible than adults to errors in drug dosage because of their smaller body size; moreover, ADRs can mimic other skin diseases of children, especially viral exanthems. Most ADRs with cutaneous involvement are mild and resolve on withdrawal of the causative drug. The most common forms of cutaneous ADRs, maculopapular exanthems and urticarial reactions, have excellent outcomes. Less frequent but more severe reactions may incur a risk of mortality.

Autoinflammatory syndromes for the dermatologist

While autoimmunity as cause of disease is well-established, other categories of immune-mediated diseases that are not produced by targeting of self-antigens by antibodies is in the process of being described. These so-called autoinflammatory diseases arise when an inappropriate activation of antigen-independent mechanisms occurs. Autoinflammatory diseases course with recurrent attacks of fever and multisystemic inflammation; however, the skin may also be affected by a variety of inflammatory manifestations that often alert the clinician about the presence of an autoinflammatory disease. Recognizing the cutaneous features of these syndromes will aid for prompt diagnosis and early treatment that is key for the quality of life and survival of the affected patients. In this paper, we focus on the skin manifestations of autoinflammatory diseases in children, which is the usual period of appearing of the first symptoms and signs.

Urticarial vasculitis in northern Spain: clinical study of 21 cases

Urticarial vasculitis (UV) is a subset of cutaneous vasculitis (CV), characterized clinically by urticarial skin lesions of more than 24 hours' duration and histologically by leukocytoclastic vasculitis. We assessed the frequency, clinical features, treatment, and outcome of a series of patients with UV. We conducted a retrospective study of patients with UV included in a large series of unselected patients with CV from a university hospital. Of 766 patients with CV, UV was diagnosed in 21 (2.7%; 9 male and 12 female patients; median age, 35 yr; range, 1-78 yr; interquartile range, 5-54 yr). Eight of the 21 cases were aged younger than 20 years old. Potential precipitating factors were upper respiratory tract infections and drugs (penicillin) (n = 4; in all cases in patients aged <20 yr), human immunodeficiency virus (HIV) infection (n = 1), and malignancy (n = 1). Besides urticarial lesions, other features such as palpable purpura (n = 7), arthralgia and/or arthritis (n = 13), abdominal pain (n = 2), nephropathy (n = 2), and peripheral neuropathy (n = 1) were observed. Hypocomplementemia (low C4) with low C1q was disclosed in 2 patients. Other abnormal laboratory findings were leukocytosis (n = 7), increased erythrocyte sedimentation rate (n = 6), anemia (n = 4), and antinuclear antibody positivity (n = 2). Treatment included corticosteroids (n = 12), antihistaminic drugs (n = 6), chloroquine (n = 4), nonsteroidal antiinflammatory drugs (n = 3), colchicine (n = 2), and azathioprine (n = 1). After a median follow-up of 10 months (interquartile range, 2-38 mo) recurrences were observed in 4 patients. Apart from 1 patient who died because of an underlying malignancy, the outcome was good with full recovery in the remaining patients. In conclusion, our results indicate that UV is rare but not exceptional. In children UV is often preceded by an upper respiratory tract infection. Urticarial lesions and joint manifestations are the most frequent clinical manifestation. Low complement serum levels are observed in a minority of cases. The prognosis is generally good, but depends on the underlying disease.

Skin rash and arthritis a simplified appraisal of less common associations

Skin and joint manifestations are part of the clinical spectrum of many disorders. Well-known associations include psoriatic arthritis and arthritis associated with autoimmune connective tissue diseases. This review focuses on less common associations where skin lesions can provide easily accessible and valuable diagnostic clues, and directly lead to the specific diagnosis or limit the list of possibilities. This may also affect health care resources as diagnostic tests are often low-specific, highly expensive and poorly available. This group of diseases can be divided into two subsets, based on the presence/absence of fever, and then further classified according to elementary skin lesions (macular, urticarial, maculo-papular, vesico-bullous, pustular, petechial and nodular). In most instances joint involvement occurs as peripheral migrating polyarthritis. Erythematosus macular or urticarial rashes occur in most febrile disorders such as monogenic autoinflammatory syndromes, Schnitzler's syndrome, Still's disease and rheumatic fever and afebrile diseases as urticarial vasculitis. Pustular rash may be observed in chronic recurrent multifocal osteomyelitis (CRMO) and pyogenic arthritis with pyoderma gangrenosum and acne (PAPA) syndrome (both febrile) as well as in Behcet's disease and Synovitis, acne, pustulosis, hyperostosis and osteitis syndrome (both non-febrile). Papular lesions are typical of secondary syphilis, sarcoidosis, interstitial granulomatous dermatitis, papular petechial of cutaneous small-vessel vasculitis and nodular lesions of polyarteritis nodosa and multicentric reticulohistiocytosis all of which are afebrile. Differential diagnosis includes infections and drug reactions which may mimic several of these conditions. To biopsy the right skin lesion at the right time it is essential to obtain relevant histological information.

Hypocomplementemic urticarial vasculitis syndrome at the onset of systemic lupus erythematosus

Different autoimmune diseases can result in urticarial eruptions, in particular, in the form of such a rare immune disorder as hypocomplementemic urticarial vasculitis syndrome (HUVS). HUVS can be the debut of diffuse connective tissue disorders, in particular, systemic lupus erythematosus (SLE). To optimize the diagnostics of this syndrome, the authors describe the course of HUVS in a female patient aged 31 suffering from SLE and characterize particular features of the differential diagnostics of HUVS with skin disorders, in the first place, chronic urticaria. The syndrome is diagnosed clinically and confirmed by histology and laboratory examinations. In addition to urticarial eruptions, HUVS is also characterized by the severe course with systemic manifestations on the part of different organs, reduction in the level of the complimentary components in the serum and detection of specific markers of the disease such as anti-C1q antibodies.

How not to miss autoinflammatory diseases masquerading as urticaria

Urticarial skin reactions are one of the most frequent problems seen by allergists and clinical immunologists in daily practice. The most common reason for recurrent wheals is spontaneous urticaria. There are, however, several less common diseases that present with urticarial rash, such as urticarial vasculitis and autoinflammatory disorders. The latter include cryopyrin-associated periodic syndrome and Schnitzler's syndrome, both rare and disabling conditions mediated by increased interleukin-1 secretion. Apart from the urticarial rash, patients are suffering from a variety of systemic symptoms including recurrent fever attacks, arthralgia or arthritis and fatigue. Autoinflammatory diseases are often associated with a diagnostic delay of many years and do not respond to antihistamines and other treatments of urticaria. Also, the chronic inflammation may lead to long-term complications such as amyloidosis. It is therefore important not to miss these diseases when diagnosing and treating patients with chronic recurrent urticarial rash. Here, we present clinical clues and tips that can help to identify autoinflammatory disorders in patients presenting with chronic urticarial rash and discuss their clinical picture and management.

Drug-induced lupus erythematosus with emphasis on skin manifestations and the role of anti-TNFα agents

Drug-induced lupus erythematosus (DILE) is a lupus-like syndrome temporally related to continuous drug exposure which resolves upon drug discontinuation. There are currently no standard diagnostic criteria for DILE. Findings include skin manifestations, arthritis, serositis, anti-nuclear and anti-histone antibodies positivity. Similarly to idiopathic lupus erythematosus, DILE can be divided into systemic (SLE), subacute cutaneous (SCLE) and chronic cutaneous lupus (CCLE). Systemic DILE presents as a milder version of idiopathic SLE, and the drugs most frequently implicated are hydralazine, procainamide and quinidine. Anti-TNFα therapies are the latest class of medications found to be associated, although rarely, with a “lupus-like” syndrome, which is however clinically distinct from classical DILE. Drug-induced SCLE is the most common form of DILE. It is very similar to idiopathic SCLE in terms of clinical and serologic characteristics. The most commonly implicated drugs are antihypertensive drugs and terbinafine, but in recent years also proton pump inhibitors and chemotherapeutic agents have been associated. Drug-induced CCLE is very rare and usually caused by fluorouracil agents and NSAIDS, but some cases have induced by pantoprazole and anti-TNFα agents.

Prolonged urticaria and fever in a toddler

We describe a 14-month-old girl who initially presented with 8 days of fever, conjunctival injection, rash, and irritability, admitted with a presumptive diagnosis of Kawasaki disease. Further history revealed intermittent urticarial-like rash since 3 months of age and pathological evaluation showed a perivascular infiltrate of neutrophils and lymphocytes. Here, we discuss the key points surrounding her diagnostic workup and our therapeutic approach.

Mycoplasma pneumoniae infection associated with urticarial vasculitis mimicking adult-onset Still's disease

Mycoplasma pneumoniae is well known to be a frequent cause of atypical pneumonia worldwide. However, it may also present with a wide variety of clinical features, including cutaneous symptoms, which are not widely recognised. Urticarial vasculitis occurring with M. pneumoniae has been described to occur in only one other case report. This amalgamation of non-specific clinical symptoms and signs can lead to a diagnostic dilemma. We describe a case of M. pneumoniae infection presenting with extrapulmonary manifestations and urticarial vasculitis, which was misdiagnosed as adult-onset Still's disease (AOSD). Had immunosuppressive therapy been commenced for AOSD in the presence of undiagnosed infection, this may have resulted in potentially serious consequences. This case highlights the need to remain vigilant about diagnosing M. pneumoniae as its serological diagnosis may take weeks and it has many extrapulmonary manifestations, which can masquerade as other conditions.

An approach to the hospitalized patient with urticaria and fever

Urticaria is a common skin disorder with a long differential diagnosis. Most cases are readily treated symptomatically and have no systemic implications. However, a number of diseases and syndromes, including vasculitides, immunologic disorders, infectious diseases, hematologic diseases, and autoinflammatory syndromes, can present with urticaria and systemic symptoms, which may lead to hospitalization of the patient. These urticarial syndromes are important to recognize as they often have significant health implications. A comprehensive history and physical exam is important in distinguishing cases of simple urticaria from these syndromes. The presence of atypical wheals, systemic symptoms such as fever or arthralgia, and a lack of response to antihistamine therapy are important diagnostic clues that should prompt further workup.

Cutaneous manifestations of Churg-Strauss syndrome: report of two cases and review of the literature

Churg-Strauss syndrome (CSS) is a small-vessel vasculitis characterized by severe asthma, lung/tissues infiltrates, extravascular necrotizing granulomas, and eosinophilia. Cutaneous involvement is common but may not be highly suggestive. Two typical cases of CSS with cutaneous involvement are herein reported, both females, 37 and 54 years old, presenting with lower limbs palpable purpura and urticarial lesions of the neck, respectively. A comprehensive review of the literature showed that cutaneous manifestations occurred in 40-81% of CSS patients and were the presenting sign in 14% of the patients. Moreover, a total of 68 cases of CSS with a detailed description of the cutaneous lesions have been published. In the majority of these patients, skin lesions allowed for the histopathological diagnosis of CSS. The most common clinical features were papulo-nodules with the histological picture of extravascular Churg-Strauss granuloma followed by purpuric and/or necrotic lesions in the lower limbs corresponding to small-vessel vasculitis with eosinophils. Less common lesions included urticarial lesions and livedo reticularis. Therefore, a high index of suspicion on skin lesions and the proper lesion selection for histological examination may be very important for early diagnosis of CSS. Clinical-pathological correlation is essential, as both clinical and histological features are not pathognomonic.