Panniculitis. Part I. Mostly septal panniculitis

Reactive Lobular Panniculitis in the Setting of Mpox (Monkeypox) Infection

ABSTRACT

Mpox, previously referred to as monkeypox, was recently deemed a public health emergency in 2022. Our understanding of potential secondary cutaneous manifestations in the setting of this infection is still evolving. We report a rare case of a man who presented with erythematous, painful subcutaneous nodules on his extremities in the setting of recent mpox infection. Biopsy of a lesion from the lower legs revealed a lobular panniculitis with lupus panniculitis-like features on pathology. He was ultimately diagnosed with a unique case of reactive panniculitis secondary to mpox.

Role of Color Doppler Ultrasound in Cutaneous Inflammatory Conditions

Inflammatory cutaneous diseases can be challenging to diagnose and manage. Nowadays, the anatomical information provided by ultrasound is critical for detecting subclinical alterations and assessing the severity and activity of these conditions. Many of these entities can be clinically observed in dermatology and other specialties, such as rheumatology, plastic surgery, ophthalmology, and otolaryngology, among others. We review the ultrasonographic patterns of the most common inflammatory cutaneous conditions. In several cases, such as hidradenitis suppurativa, acne, and morphea, there are ultrasonographic staging systems of severity or activity that are pivotal in the management of these diseases. The early ultrasonographic diagnosis of these entities implies a proper management of the patients and, therefore, improve their quality of life. Thus, knowledge of the current use of ultrasound in this field seems essential.

Phase 1 trial evaluating safety and pharmacokinetics of HIV-1 broadly neutralizing mAbs 10E8VLS and VRC07-523LS

BACKGROUNDBroadly neutralizing monoclonal antibodies (bNAbs) represent a promising strategy for HIV-1 immunoprophylaxis and treatment. 10E8VLS and VRC07-523LS are bNAbs that target the highly conserved membrane-proximal external region (MPER) and the CD4-binding site of the HIV-1 viral envelope glycoprotein, respectively.METHODSIn this phase 1, open-label trial, we evaluated the safety and pharmacokinetics of 5 mg/kg 10E8VLS administered alone, or concurrently with 5 mg/kg VRC07-523LS, via s.c. injection to healthy non-HIV-infected individuals.RESULTSEight participants received either 10E8VLS alone (n = 6) or 10E8VLS and VRC07-523LS in combination (n = 2). Five (n = 5 of 8, 62.5%) participants who received 10E8VLS experienced moderate local reactogenicity, and 1 participant (n = 1/8, 12.5%) experienced severe local reactogenicity. Further trial enrollment was stopped, and no participant received repeat dosing. All local reactogenicity resolved without sequelae. 10E8VLS retained its neutralizing capacity, and no functional anti-drug antibodies were detected; however, a serum t1/2 of 8.1 days was shorter than expected. Therefore, the trial was voluntarily stopped per sponsor decision (Vaccine Research Center, National Institute of Allergy and Infectious Diseases [NIAID], NIH). Mechanistic studies performed to investigate the underlying reason for the reactogenicity suggest that multiple mechanisms may have contributed, including antibody aggregation and upregulation of local inflammatory markers.CONCLUSION10E8VLS resulted in unexpected reactogenicity and a shorter t1/2 in comparison with previously tested bNAbs. These studies may facilitate identification of nonreactogenic second-generation MPER-targeting bNAbs, which could be an effective strategy for HIV-1 immunoprophylaxis and treatment.TRIAL REGISTRATIONClinicaltrials.gov, accession no. NCT03565315.FUNDINGDivision of Intramural Research, National Institute of Allergy and Infectious Diseases, NIH.

Panniculitis: A Cardinal Sign of Autoinflammation

Panniculitis was first described in the nineteenth century and is characterized by inflammation of the subcutaneous fat. It may be categorized in septal or lobular subtypes, but other histopathological features (e.g., presence of vasculitis, nature of inflammatory infiltrates, characteristics of fat necrosis) are also important for diagnostic purposes. Clinically, panniculitis is characterized by the presence of subcutaneous nodules, and both ulcerative and nonulcerative clinical subtypes have been proposed. In this review, we aimed to describe the occurrence of panniculitis in autoinflammatory disorders (AIDs) and related diseases. Among monogenic AIDs, panniculitis is common in IFN-mediated disorders. Panniculitis is a distinctive feature in proteasome-associated autoinflammatory syndromes (PRAAS), including chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature (CANDLE) syndrome and Nakajo-Nishimura syndrome. On the other hand, erythema nodosum corresponds to the most common clinical form of panniculitis and is common in polygenic AIDs, such as Behçet's syndrome, inflammatory bowel disease, and sarcoidosis. Cytophagic histiocytic panniculitis, lipoatrophic panniculitis of children, and otulipenia are rare disorders that may also present with inflammation of the subcutaneous fat. Therefore, panniculitis can identify a specific subgroup of patients with AIDs and may potentially be regarded as a cardinal sign of autoinflammation.

Superficial (nodular) thrombophlebitis as a heterogeneous entity with distinctive clinico-pathological aspects: Correlation with the underlying conditions

BACKGROUND

Superficial (nodular) thrombophlebitis, referring to a thrombo-inflammatory disorder of dermal-subcutaneous veins, encompass a spectrum of nodular lesions often associated with inflammatory, infectious, neoplastic or thrombophilic diseases.

OBJECTIVE

We postulate that distinct clinico-pathological features may correlate with the underlying conditions.

METHODS

We conducted a retrospective monocentric study of all patients seen in our dermatology department for a superficial thrombophlebitis, completed with a literature review. Clinical and pathological data were extracted from the patient files and articles.

RESULTS

A total of 108 cases of superficial thrombophlebitis was analysed. Forty-five percent manifested as elongated nodules clearly evoking vascular involvement, while the other 55% were presenting as nodules or plaques. The elongated phenotype was strongly associated with malignancy or thrombophilia if a pure thrombosis was demonstrated histopathologically, while tuberculosis was the main underlying condition if a granulomatous vasculitis was present. Panniculitis-like lesions were mainly corresponding to erythema-nodosum-like lesions of Behçet's disease, characterized by the distinctive feature of thrombotic veins with an associated leukocytoclastic vasculitis.

LIMITATIONS

Retrospective design and risk of publication bias.

CONCLUSION

Superficial (nodular) thrombophlebitis is a heterogeneous entity with a distinct clinico-pathological presentation that strongly points to the nature of the underlying medical condition, thus guiding the medical workup.

A comprehensive summary of disease variants implicated in metal allergy

Allergic disease represents one of the most prominent global public health crises of the 21^st century. Although many different substances are known to produce hypersensitivity responses, metals constitute one of the major classes of allergens responsible for a disproportionately large segment of the total burden of disease associated with allergy. Some of the most prevalent forms of metal allergy - including allergic contact dermatitis - are well-recognized; however, to our knowledge, a comprehensive review of the many unique disease variants implicated in human cases of metal allergy is not available within the current scientific literature. Consequently, the main goal in composing this review was to (1) generate an up-to-date reference document containing this information to assist in the efforts of lab researchers, clinicians, regulatory toxicologists, industrial hygienists, and other scientists concerned with metal allergy and (2) identify knowledge gaps related to disease. Accordingly, an extensive review of the scientific literature was performed - from which, hundreds of publications describing cases of metal-specific allergic responses in human patients were identified, collected, and analyzed. The information obtained from these articles was then used to compile an exhaustive list of distinctive dermal/ocular, respiratory, gastrointestinal, and systemic hypersensitivity responses associated with metal allergy. Each of these disease variants is discussed briefly within this review, wherein specific metals implicated in each response type are identified, underlying immunological mechanisms are summarized, and major clinical presentations of each reaction are described.Abbreviations: ACD: allergic contact dermatitis, AHR: airway hyperreactivity, ASIA: autoimmune/ autoinflammatory syndrome induced by adjuvants, BAL: bronchoalveolar lavage, CBD: chronic beryllium disease, CTCL: cutaneous T-cell lymphoma, CTL: cytotoxic T-Lymphocyte, DRESS: drug reaction with eosinophilia and systemic symptoms, GERD: gastro-esophageal reflux disease, GI: gastrointestinal, GIP: giant cell interstitial pneumonia, GM-CSF: granulocyte macrophage-colony stimulating factor, HMLD: hard metal lung disease, HMW: high molecular weight, IBS: irritable bowel syndrome, Ig: immunoglobulin, IL: interleukin, LMW: low molecular weight, PAP: pulmonary alveolar proteinosis, PPE: personal protective equipment, PRR: pathogen recognition receptor, SLE: systemic lupus erythematosus, SNAS: systemic nickel allergy syndrome, Th: helper T-cell, UC: ulcerative colitis, UV: ultraviolet.

Erythema Nodosum in Children: A Narrative Review and a Practical Approach

Erythema nodosum (EN) is the most frequent form of panniculitis in children. We performed a literature review analyzing studies on pediatric EN published from 1990 to February 2022. EN is rare in pediatric age. It can be primary/idiopathic in 23–55% cases, or secondary in 47–77% cases. Secondary EN is related to a wide variety of conditions including infectious diseases, autoimmune disorders, malignancy, drugs, vaccinations, and pregnancy. The diagnosis of EN is clinical, based on the acute appearance of painful and red nodules localized to lower limbs, bilaterally distributed. If EN is diagnosed, basic work-up should include inflammatory markers, serum aminotransferases, lactate dehydrogenase, creatinine, protein electrophoresis, immunoglobulins, testing for streptococcal infection, and a tuberculin skin test. Based on the medical history and associated manifestations, further laboratory and radiological exams should be performed. The prognosis of EN is excellent, with spontaneous resolution in most patients within 2–6 weeks. Treatment, if needed, is addressed to the underlying condition. Despite being a rare manifestation in children, EN can be isolated or the first manifestation of a systemic or infectious condition. EN diagnosis is clinical, and a high index of suspicion is needed to perform investigations for the underlying disorders.

Brucella as an unexpected cause of erythema nodosum

Erythema nodosum (EN) is the most common panniculitis which affects individuals from all ages. Etiologically most of the cases are idiopathic EN and infections rank the second. Its clinical presentation is sudden, hot erythematous nodules or plaques in legs, knees or ankles with a diameter ranging between 1 and 5 cm. In the majority of cases, healing is observed within two to eight weeks without any scar tissues. It may occasionally manifest itself as the first symptom of systemic diseases such as sarcoidosis, inflammatory bowel diseases, Behçet’s disease, and other rheumatological conditions. Therefore, EN cases must be carefully examined in terms of their etiologies. Herein, we report an interesting Brucella case presenting as a EN case consulted for rheumatological etiology investigation.

Clinicopathological Characteristics Related to Etiologies of Erythema Nodosum: A 10-Year Retrospective Study

Background

Erythema nodosum (EN) is the most common panniculitis associated with a wide variety of conditions. Updated studies regarding the clinicopathological manifestations related to etiologies of EN and its prognosis are limited.

Objective

We aimed to explore the clinicopathological features in relation to the etiologies of EN and determine characteristics of disease recurrence and its predictive factors.

Methods

A total of 169 patients with biopsy-proven EN or septal panniculitis from January 2008 to September 2018 were retrospectively reviewed. Patients were classified as either idiopathic or secondary EN. Patients’ general information, clinical manifestations, investigations, and recurrence of EN were recorded. The details on histopathological findings were reviewed by a blinded dermatopathologist.

Results

The mean age at diagnosis of EN was 40.6 ± 17.3 years. The majority of patients (85.2%) were female. Idiopathic EN was found in 62.7% of patients. Tuberculosis (23.8%) and drugs (23.8%) were the leading causes of secondary EN. In univariate logistic regression analysis, lesions on upper extremities (p = 0.018), fever (p = 0.003), clinical lymphadenopathy (p < 0.001) favored secondary EN. Histopathologically, the presence of focal peripheral lobular panniculitis with eosinophils was linked to idiopathic EN (p = 0.03). However, multivariable logistic regression analysis failed to demonstrate factors associated with secondary EN. Recurrence was found in 46.6% of patients with no identifiable predictive factors.

Conclusion

Although no clinical risk factors were associated with the etiology of EN, the histopathological presence of eosinophils in focal peripheral lobular panniculitis suggested idiopathic EN.

Panniculitis in Children

Panniculitides form a heterogenous group of inflammatory diseases that involve the subcutaneous adipose tissue. These disorders are rare in children and have many aetiologies. As in adults, the panniculitis can be the primary process in a systemic disorder or a secondary process that results from infection, trauma or exposure to medication. Some types of panniculitis are seen more commonly or exclusively in children, and several new entities have been described in recent years. Most types of panniculitis have the same clinical presentation (regardless of the aetiology), with tender, erythematous subcutaneous nodules. Although the patient's age and the lesion site provide information, a histopathological assessment is sometimes required for a definitive diagnosis and classification of the disorder. In children, most panniculitides are lobular. At present, autoimmune inflammatory diseases and primary immunodeficiencies have been better characterised; panniculitis can be the presenting symptom in some of these settings. Unexplained panniculitis in a young child should prompt a detailed screen for monogenic immune disorders because the latter usually manifest themselves early in life. Here, we review forms of panniculitis that occur primarily in children, with a focus on newly described entities.

Panniculitis as a manifestation of metal-associated autoimmune/inflammatory syndrome induced by adjuvants: a case-based review

Autoimmune/inflammatory syndrome induced by adjuvants (ASIA) is associated with a hyperergic response of the immune system. The spectrum of clinical changes in ASIA is extensive and difficult to diagnose. Panniculitis is a heterogeneous group of diseases characterized by lesions of the adipose tissue. Panniculitis may become one of the signs of ASIA progress.To describe the clinical signs and morphological changes in the subcutaneous fat as a manifestation of ASIA, developing after osteosynthesis with metal structures.In this case-based review, were searched for all articles published in PubMed and Scopus databases until March, 2021 using the following keywords "panniculitis", "erythema nodosum", "Weber-Christian Disease", "idiopathic lobular panniculitis", "Autoimmune/inflammatory syndrome induced by adjuvants", "Shoenfeld's syndrome", "metal allergy" "metal implants", "metal hypersensitivity" and reviewed them. Irrelevant items and duplicates were excluded.We report a case of an adult female patient presenting with a non-healing uninfected surgical wound following implantation of metal osteosynthesis construction and panniculitis developed after surgery. A comprehensive examination of the patient to check for ASIA was conducted. Considering the medical history of exposure to metals, tissue lesions, arthralgia, myalgia, low-grade fever, the disappearance of symptoms on the background of immunosuppressive therapy suggested the diagnosis of ASIA.Report affords clinicians and pathologists additional insight into the clinical and morphological picture of ASIA-associated panniculitis which, if remain unidentified, may cause severe complications. We recommend the removal of constructions with adjuvant activity in patients with suspected ASIA-associated manifestations.

Investigating the presence of neutrophil extracellular traps in septal and lobular cutaneous panniculitides

BACKGROUND

Panniculitides are a heterogeneous group of inflammatory dermatoses involving the subcutaneous fatty tissue. Histologically, they are classified into septal and lobular panniculitis, according to the predominant localization of the inflammatory infiltrate. Neutrophils are frequently found in panniculitis, mainly at the early stages. Here, we investigated whether neutrophils contribute to various types of cutaneous panniculitis by releasing neutrophil extracellular traps (NETs).

MATERIALS AND METHODS

Formalin-fixed paraffin-embedded skin biopsies from 25 patients with panniculitis were included in the study. Our cohort was divided into n = 10 erythema nodosum (septal panniculitis) and n = 15 lobular panniculitis, including n = 7 lupus panniculitis, n = 1 pancreatic panniculitis, n = 1 Weber-Christian disease, n = 1 deep fungal infection, n = 2 lipodermatosclerosis, and three cases did not have an identified etiology. The presence of neutrophils and NETs was assessed by double immunofluorescence using antibodies against elastase, a neutrophilic marker, and citrullinated histone 3, a marker of NETs.

RESULTS

The mean percentages (±SEM) of elastase-positive neutrophils showing NETs were 44% ± 3% in erythema nodosum and 43% ± 7% in lobular panniculitis. The difference was not statistically significant and reflects the implication of NETs not only in severe scarring lobular panniculitis but also in benign non-scarring self-remitting reactive inflammation such as erythema nodosum. In tissues, NETs were located in the interlobular septa in erythema nodosum and in the inflamed fat lobules in lobular panniculitis.

CONCLUSIONS

NETs are massively present in septal and lobular subtypes of panniculitides, suggesting their involvement in tissue damage.

Methicillin-resistant Staphylococcus aureus (MRSA) panniculitis in a patient undergoing stem cell mobilisation

Methicillin-resistant Staphylococcus aureus (MRSA) can cause a wide range of skin infections, however MRSA panniculitis without bacteremia is a rare manifestation. Here, we report a woman in her 20s with relapsed Hodgkin lymphoma undergoing stem cell mobilisation who presented with bilateral subcutaneous nodules over her shins. Ultrasound scan of one nodule showed non-specific inflammatory changes. Punch biopsy of a nodule showed lobular panniculitis with Gram-positive cocci. Blood cultures were negative but a culture from the biopsy grew MRSA. She was started on doxycycline with improvement in her symptoms. This case serves as a reminder to consider infections as a cause of panniculitis in immunocompromised patients.

[Cutaneous vasculitis and vasculopathy : Differential diagnosis in biopsies of the lower extremities]

The skin is one of the most frequently involved organs in primary systemic and secondary vasculitis; moreover, a vasculitis can occur as single organ vasculitis, limited to the skin. For most types of vasculitis, the lower extremities constitute common sites with clinical symptoms of palpable purpura, nodules, and ulcers. In histopathology of cutaneous vasculitis, it is of utmost importance to correctly identify the vessel types involved and to discriminate between vasculitic vessel damage, unspecific reactive vessel changes, vascular occlusive diseases, noninflammatory purpura, or perivascular infiltrates due to other inflammatory skin diseases. Small-vessel vasculitis is the most frequent type of cutaneous vasculitis; during florid phases, a dermal leukocytoclastic vasculitis is found regardless of etiology. Additional extravascular changes may give etiological clues, however, a correlation with the clinical picture, radiology, and serology is essential. The biopsy type and technique need to be adjusted to the suspected diagnosis and site of the vessels involved. Polyarteritis nodosa and nodular vasculitis can be diagnosed only in biopsies with sufficient subcutaneous tissue. Especially in cutaneous ulcers, a lateral rim of vital skin and subcutaneous tissue is indispensable for a correct diagnosis. Large-vessel vasculitis is not found in skin biopsies of the lower extremities.

Pancreatic panniculitis in a patient with pancreatic adenosquamous carcinoma

Pancreatic panniculitis is a rare complication of pancreatic diseases. We aimed to evaluate a case of pancreatic panniculitis. A 58-year-old woman was referred to our hospital with complaints of painful cutaneous nodules on her limbs. Various diagnostic tests confirmed pancreatic panniculitis and pancreatic adenosquamous carcinoma. We diagnosed pancreatic panniculitis by a skin nodule biopsy that revealed fine basophilic material within anucleate cells and neutrophil infiltration. Abdominal imaging detected a tumor with necrosis on the pancreas and endoscopic ultrasound-guided fine-needle aspiration revealed it as an adenocarcinoma. The patient underwent pancreatoduodenectomy after neoadjuvant chemotherapy. The tumor was composed of differentiated adenocarcinoma and squamous cell carcinoma and diagnosed as adenosquamous carcinoma. This is the first report of pancreatic panniculitis in a patient with adenosquamous cell carcinoma of the pancreas.

Ulcerative versus non-ulcerative panniculitis: is it time for a novel clinical approach to panniculitis?

Panniculitis, or inflammation of the fatty tissue, is an ongoing diagnostic challenge to both dermatologists and pathologists. The basis of the current panniculitis classification is histology, whether the inflammation is mainly located in the fibrovascular septa or in the adipose lobules thereafter with or without vasculitis. However, overall, the difficulty rises due to various terminologies and lack of clinical relevance with this classification. In addition to that, the majority of panniculitides have mixed infiltration of both lobular and septal and not a clear-cut distinction. The aim of this article is to provide a novel clinical algorithm to the diagnosis of panniculitis and thus to provide guidelines for all clinicians who may encounter this challenging condition in their clinical practice.

Screening Sarcoidosis Patients for Occult Disease

As sarcoidosis may involve any organ, sarcoidosis patients should be evaluated for occult disease. Screening for some organ involvement may not be warranted if it is unlikely to cause symptoms, organ dysfunction, or affect clinical outcome. Even organ involvement that affects clinical outcome does not necessarily require screening if early detection fails to change the patient's quality of life or prognosis. On the other hand, early detection of some forms of sarcoidosis may improve outcomes and survival. This manuscript describes the approach to screening sarcoidosis patients for previously undetected disease. Screening for sarcoidosis should commence with a meticulous medical history and physical examination. Many sarcoidosis patients present with physical signs or symptoms of sarcoidosis that have not been recognized as manifestations of the disease. Detection of sarcoidosis in these instances depends on the clinician's familiarity with the varied clinical presentations of sarcoidosis. In addition, sarcoidosis patients may present with symptoms or signs that are not related to specific organ involvement that have been described as parasarcoidosis syndromes. It is conjectured that parasarcoidosis syndromes result from systemic release of inflammatory mediators from the sarcoidosis granuloma. Certain forms of sarcoidosis may cause permanent and serious problems that can be prevented if they are detected early in the course of their disease. These include (1) ocular involvement that may lead to permanent vision impairment; (2) vitamin D dysregulation that may lead to hypercalcemia, nephrolithiasis, and permanent kidney injury; and (3) cardiac sarcoidosis that may lead to a cardiomyopathy, ventricular arrhythmias, heart block, and sudden death. Screening for these forms of organ involvement requires detailed screening approaches.

A rare case of a patient with PPP syndrome presenting pancreatic pseudocysts, panniculitis, and symptoms of polyarthritis. A radicular cyst of the upper jaw could be another manifestation of the syndrome

In rare cases, pancreatic enzymes can enter the bloodstream and cause fat necrosis in the bone and tissue leading to a disorder called pancreatitis, panniculitis, and polyarthritis syndrome. Clinicians should have this syndrome in mind when treating patients with pancreatitis.

Inter- and Intra-rater Agreement of Dermatologic Ultrasound for the Diagnosis of Lobular and Septal Panniculitis

OBJECTIVES

Dermatologic ultrasound (US) may aid in the diagnosis and classification of panniculitis. The purpose of this study was to assess the capability of dermatologic US for subtyping mainly septal/lobular panniculitis.

METHODS

A multicentric and prospective study of the inter- and intra-rater agreement of dermatologic US for subtyping panniculitis was conducted among 4 clinicians with experience in dermatologic US and a radiologist specialized in dermatologic US. Clinicians recruited patients and performed dermatologic US examinations of the most substantial lesion and punch biopsies. A histologic study was considered the reference standard. Then the images were blindly evaluated by all researchers. For intra- and inter-rater agreement, Cohen and Fleiss κ values were calculated.

RESULTS

Sixty-four patients were included. The Cohen intra-rater κ was 0.74. Sensitivity and specificity for lobular panniculitis were 85.19 and 88.57, respectively. The Fleiss inter-rater κ was 0.47. Limitations of the study included the small number of patients and differences in evaluators and their dermatologic US equipment.

CONCLUSIONS

This study supports the use of US for diagnosing panniculitis. For subtyping panniculitis, the intra-rater correlation was good. Improvement of inter-rater agreement may depend on access to clinical information, dynamic images, a better definition of criteria, homogeneous configurations of the devices, and the expertise of dermatologic US operators.

[Idiopatic Lobular Panniculitis as a common clinical problem]

AIM

To present clinical and laboratory characteristics of various forms of idiopatic lobular panniculitis (ILP) in modern rheumatology practice.

MATERIALS AND METHODS

The study included 67 people (58 women and 9 men aged 20 to 76) with the referral diagnosis of "Erythema nodosa? Undifferentiated panniculitis?" in 76.2% of cases with a median disease duration of 78.91 [48; 540] months observed in the V.A. Nasonova Research Institute of Rheumatology. In 2007-2017 in addition to general clinical examination immunological, histological and immunohistochemical studies, computed tomography (CT) of the chest organs and tuberculin tests were performed.

RESULTS

Analysis of clinical manifestations allowed to distinguish four forms of ILP: nodular (n=30), plaque (n=10), infiltrative (n=15) and mesentric (n=12). The minimum median duration of the disease was detected in plaque form (8 [5; 11.5] months), while the median duration in case of infitrative form was 8.25 times longer (66 [36; 102] months, p38 °C and a small number (up to 5) of drain nodes; infiltrative - fever >38 °C, ulceration of nodes with the expiration of oily mass and scarring; mesenteric - pain in the abdominal area, the number of nodes less than 5 and the abdominal cavity CT results (inflammation of the adiopose tissue of the intestinal mesentery, omentum, adipose tissue of the pre - and retroperitoneal areas).

CONCLUSION

The forms and activity of the disease determine the approaches to treatment in modern clinical practice. There is an obvious need to expand knowledge about this pathology among doctors and conduct further research in order to timely diagnose and search for the most effective methods of ILP treatment.

Elevated neutrophil to lymphocyte ratio as an indicator of secondary erythema nodosum, a retrospective observational study

Background/aim

Erythema nodosum (EN) is an inflammatory disorder of subcutaneous tissue. Although etiopathogenesis of the disease is unknown, many predisposing factors such as infections, systemic disease, and drugs have been identified. Neutrophil to lymphocyte ratio (NLR) has been shown to be a novel inflammatory marker in many dermatological diseases. The aim of our study is to investigate NLR in EN patients and evaluate its relation to the underlying cause of the disease.

Materials and methods

Between 2014 and 2018, clinical and laboratory data of 395 patients diagnosed with EN and 395 controls were extracted from patient files. EN patients were grouped as idiopathic EN and secondary EN (EN with an identified underlying cause). Clinical and laboratory characteristics of the two groups were compared

Results

NLR was elevated in EN patients compared to controls (median of 2.38 vs. 1.55, P < 0.001). Among EN patients, NLR was also elevated in patients with secondary EN. In multivariate logistic regression model NLR (> 2.11), RDW-CV (> 13.65), and CRP (> 5.5) were identified as risk factors for secondary EN (relative risks were 17.16, 2.69, and 2, respectively).

Conclusion

Elevated NLR (> 2.11) may be used as a parameter to discriminate secondary EN from idiopathic EN.

Cutaneous Polyarteritis Nodosa: Uncommon and Rare Form of Cutaneous Vasculitis

Cutaneous polyarteritis nodosa (CPAN) is a variant of polyarteritis nodosa that is limited primarily to the skin. It is a chronic recurrent disorder characterized by the presence of nodular lesions with or without ulceration on the distal third of the lower limbs. Nodular vasculitis and thrombophlebitis can be clinically or pathologically mistaken for CPAN. We present a case of a 51-year-old woman with painful nodules on the lower limbs. Some of the nodules were ulcerated. Histopathological examination of a nodule on deep incisional biopsy revealed fibrinoid necrosis of a medium-sized artery in the subcutis along with perivascular mixed infiltrate. The patient did not have any symptoms or signs of internal organ involvement. The possible etiological factor has not been detected. The patient was treated with oral prednisone 0.5 mg/kg/day and dapson 150 mg/day. Over the one-year follow-up the lesions showed regression, with one minimal relapse which resolved after the short course of oral prednisone.

Breast panniculitis with liquefactive fat necrosis: A case report

Panniculitis is a group of heterogeneous disorders characterized by inflammation of the subcutaneous adipose tissue. Panniculitis of breast tissue as the initial manifestation has rarely been reported and is often misdiagnosed. Breast panniculitis may cause substantial morbidity and early diagnosis and treatment are important for the prognosis of the disease. The present study has reported a case of panniculitis with inflammation of the mammary glands as the initial presentation and provided a detailed description of ultrasonography, X-ray, computed tomography, magnetic resonance imaging and other imaging features of breast panniculitis. The treatment and follow-up were also described. Following treatment with systemic corticosteroids combined with methotrexate and thalidomide for 2 months, the breast appeared to be normal without scar formation. The present case report provides a good reference for the future diagnosis and treatment of breast panniculitis.

Nomenclature of Cutaneous Vasculitis: Dermatologic Addendum to the 2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides

OBJECTIVE

To prepare a dermatologic addendum to the 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides (CHCC2012) to address vasculitides affecting the skin (D-CHCC). The goal was to standardize the names and definitions for cutaneous vasculitis.

METHODS

A nominal group technique with a facilitator was used to reach consensus on the D-CHCC nomenclature, using multiple face-to-face meetings, e-mail discussions, and teleconferences.

RESULTS

Standardized names, definitions, and descriptions were adopted for cutaneous components of systemic vasculitides (e.g., cutaneous IgA vasculitis as a component of systemic IgA vasculitis), skin-limited variants of systemic vasculitides (e.g., skin-limited IgA vasculitis, drug-induced skin-limited antineutrophil cytoplasmic antibody-associated vasculitis), and cutaneous single-organ vasculitides that have no systemic counterparts (e.g., nodular vasculitis). Cutaneous vasculitides that were not included in the CHCC2012 nomenclature were introduced.

CONCLUSION

Standardized names and definitions are a prerequisite for developing validated classification and diagnostic criteria for cutaneous vasculitis. Accurate identification of specifically defined variants of systemic and skin-limited vasculitides requires knowledgeable integration of data from clinical, laboratory, and pathologic studies. This proposed nomenclature of vasculitides affecting the skin, the D-CHCC, provides a standard framework both for clinicians and for investigators.

Sclerema Neonatorum in a Full-Term Infant Showing Favorable Prognosis

Sclerema neonatorum (SN) is a rare disease characterized by firm, indurated, waxy skin lesions extending throughout the body, sparing the fat-free soles, palms, and genitalia. The prognosis of SN is generally very poor, with a high fatality rate. We report the case of a full-term infant with delayed onset of SN showing good prognosis. A 4-month-old Korean male infant presented with diffuse waxy, sclerotic skin lesions on the whole body, sparing the face, nipples, and genital area, which began developing at 2 months of age. Histopathologic findings of the sclerotic skin lesions showed wide, fibrous intersecting bands in the subcutaneous fat tissue. Only sparse infiltration of lymphocytes and histiocytes was observed in the fat lobules and septa. Based on clinical presentation and histopathologic findings, he was diagnosed with SN. The patient survived with conservative care and had mild improvement of the skin lesions on his follow-up visit at 12 months of age.

[Not Available]

Zusammenfassung. Erythema nodosum ist die häufigste Form einer akuten Pannikulitis. Klinisch manifestiert es sich als erythematöse bis livide, druckdolente, subkutane Plaques und Knoten. Diese treten meist symmetrisch im Bereich der Unterschenkelstreckseiten auf. Die häufigsten Auslöser sind Infekte und entzündliche Erkrankungen; in etwa der Hälfte der Fälle lässt sich keine Ursache finden. Aufgrund der Heterogenität der Trigger und des meist selbstlimitierenden Verlaufes stellt sich in der Praxis die Frage, was die Ursache ist und inwieweit sie gesucht werden soll. In diesem Artikel möchten wir auf die Abklärungsstrategie und die wichtigsten Auslöser des Erythema nodosum eingehen.

[Differential diagnosis of panniculitides]

Panniculitides are diseases of the subcutaneous tissue with heterogeneous etiology. They may develop consequent to infections, as a reaction to drugs, after thermal injury, as part of autoimmune diseases, in metabolic disorders or due to infectious organisms. The clinical presentation with subcutaneous nodules is often nonspecific. Moreover, the differentiation from vasculitides of medium-sized vessels can be clinically challenging. Microscopic examination of biopsy specimens is of high importance in the differential diagnosis of panniculitides. Histopathologically, panniculitides can be classified according to the predominantly infiltrated area in septal and lobular panniculitides and they can be separated from vasculitides of medium-sized vessels. Diagnostic difficulties arise from inadequate biopsy specimens and from lack of clinicopathological correlation. This article summarizes diagnostic criteria of frequent and clinically important panniculitides.

Panniculitis: A summary

The diagnosis of panniculitis is felt to be a confusing topic by some pathologists. This summarical article presents inflammatory diseases of the subcutis in a systematic fashion, based on whether they are centered on fibrovascular septa or the adipose lobules, and whether morphologic vasculitis is present or not. Septocentric, non-vasculitis disorders include erythema nodosum, panniculitis that follows the use of "biological" therapeutic agents, lipodermatosclerosis, post-irradiation panniculitis, morphea profunda, and necrobiosis lipodica profunda. Polyarteritis nodosa and Behçet's disease are the conditions that are based in the subcutaneous septa with vasculitis. Predominantly-lobular panniculitides with no vasculitis include pancreatogenic panniculitis, the panniculitis of alpha-1-antitrypsin deficiency, panniculitis associated with lupus erythematosus and dermatomyositis, subcutaneous Sweet syndrome, eosinophilic panniculitis, factitial panniculitis, cold panniculitis, panniculitis following injections of corticosteroids, lipomembranous (ischemic) panniculitis; sclerema neonatorum and subcutaneous fat necrosis of the newborn, and Rosai-Dorfman disease of the subcutis. Erythema induratum and infectious panniculitis are vasculitic and lobulocentric conditions. This article reviews the histological features of these diseases.

Purulent lupus panniculitis unmasked by FDG-PET/CT scan: A case report

RATIONALE

Lupus panniculitis (LP) is a unique variant of cutaneous lupus erythematosus. Clinical manifestations are typically mild and include erythema, nodules, and small ulcers. In certain cases, diagnosing LP may be challenging. Skin overlying the typical subcutaneous inflammation may appear normal, and bacterial superinfections of the skin sometimes mask the underlying LP. It has been suggested that a computed tomography (CT) scan may help to identify obscure LP lesions. Here, we report a case of a 54-year-old woman with an unusually severe form of LP, in which the full disease extent was only revealed by a fluorodeoxyglucose positron emission tomography (FDG-PET)/CT scan.

PATIENT CONCERNS/DIAGNOSES/INTERVENTIONS/OUTCOMES

Our patient initially presented with a bacterial infection of the skin. After initial improvement with antibiotic treatment, new erythematous lesions and sterile subcutaneous pus collections developed. An FDG-PET/CT scan revealed extensive subcutaneous inflammation at sites that had appeared normal during physical examination and on CT scan. As the subcutaneous lesions showed a remarkably linear pattern on FDG-PET/CT scan, the patient was suspected of having LP. After confirmation of this diagnosis by a deep-skin biopsy, our patient was treated with systemic glucocorticoids. Eventually, our patient succumbed to complications of LP and its treatment.

LESSONS

Our case demonstrates that clinical manifestations of LP are not always mild and that timely diagnosis is needed. Furthermore, we show that obscure LP lesions are more readily identified on an FDG-PET/CT scan than CT scan.

Erythema nodosum and the risk of tuberculosis in a high incidence setting

OBJECTIVE

This study estimates the erythema nodosum (EN) incidence in a tuberculosis (TB) endemic setting and evaluates the likelihood of a subsequent TB diagnosis among individuals with Mycobacterium tuberculosis infection (MTI) with or without EN.

DESIGN

We estimated EN incidence rates (IRs) in East Greenland in 2010-2011 and conducted a cohort study following all individuals who tested positive for MTI from 1 January 2010 until 31 December 2012. A personal identifier allowed individual follow-up in the mandatory TB register. MTI was defined by a positive interferon-gamma release assay. TB incidence rate ratios (IRRs) among participants with or without EN were estimated with the Cox proportional hazard model.

RESULTS

We identified 38 EN cases corresponding to an IR of 500/100,000 inhabitants/year. All cases were among individuals with MTI. The EN IR was 11.79 (95% CI 5.73-24.27) times higher for BCG-unvaccinated compared with BCG-vaccinated individuals. The TB IRR was 25 (95% CI 11-60) within 1 month of EN compared to individuals without EN.

CONCLUSION

This study documents a high EN incidence in a TB endemic region. EN occurred only in individuals with MTI, and predominantly among BCG-unvaccinated individuals. EN was significantly associated with a TB diagnosis within 1 month of diagnosis.

[Cutaneous panniculitis]

Panniculitis is an inflammation of the subcutaneous fat. Skin biopsy plays a critical role in the differential diagnosis of panniculitis. The most common approach to diagnosis relies on the differentiation between predominantly septal or lobular panniculitis, followed by the distinction between lesions with and without vasculitis. It is also very important to submit a part of the skin biopsy for microbiological analysis and for T-cell clonal expansion if T-cell lymphoma is suspected. Erythema nodosum, the most frequent septal panniculitis, has many causes and in its typical clinical presentation, does not require skin biopsy. In other panniculitis, diagnosis is based on the integration of the clinical and histological data, which renders a deep cutaneous biopsy necessary. Periarteritis nodosa, a septal panniculitis with vasculitis characterized by subcutaneous nodules and livedo racemosa, can be associated with systemic involvement. Nodular thrombophlebitis needs search for associated coagulopathy, Behçet's disease, periarteritis nodosa or Buerger's disease. Lobular panniculitis are classified according to the nature of cells present in the inflammatory infiltrate. If there is a lymphocytic infiltration, lupus panniculitis is difficult to differentiate from subcutaneous panniculitis-like T-cell lymphoma. If there are histiocytes, it can be a sarcoidosis, a cytophagic histiocytic panniculitis or, in newborn, a subcutaneous fat necrosis. Neutrophilic panniculitis needs careful clinic-pathologic correlation. Treatment of panniculitis can be challenging and is based on the histopathological findings. Frequently, the precise cause of panniculitis cannot be established from the outset, so it is important to follow-up patients and not hesitate to repeat the skin biopsy.

Lupus mastitis of the male breast

A 39-year-old male with no known co-morbid conditions presented with gradually increasing bilateral breast lumps for 1.5 years. Clinically, tender subcutaneous masses were detected. Mammograms revealed masses on both sides that on ultrasound were hyperechoic and showed internal vascularity. An MRI was suggested to assess the extent of the disease that confirmed bilateral masses but was otherwise inconclusive. Core biopsy revealed evidence of panniculitis with likely autoimmune aetiology. Evaluation of autoimmune markers was carried out that was positive and multidisciplinary team discussion concluded the diagnosis as lupus mastitis. Male breast pathology and lupus mastitis are both uncommon conditions, making lupus mastitis of male breast an extremely unusual presentation. However, its close clinical and radiological similarity with malignancy makes it important in spite of its rarity. Here we report a case of bilateral lupus mastitis in male breast with its radiological features.

Lymphocytic panniculitis: an algorithmic approach to lymphocytes in subcutaneous tissue

The diagnosis of panniculitis is a relatively rare occurrence for many practising pathologists. The smaller subset of lymphocyte-predominant panniculitis is further complicated by the diagnostic consideration of T cell lymphoma involving the subcutaneous tissue, mimicking inflammatory causes of panniculitis. Accurate classification of the panniculitis is crucial to direct clinical management as treatment options may vary from non-medical therapy to immunosuppressive agents to aggressive chemotherapy. Many diseases show significant overlap in clinical and histological features, making the process of determining a specific diagnosis very challenging. However, with an adequate biopsy including skin and deep subcutaneous tissue, a collaborative effort between clinician and pathologist can often lead to a specific diagnosis. This review provides an algorithmic approach to the diagnosis of lymphocyte-predominant panniculitis, including entities of septal-predominant pattern panniculitis (erythema nodosum, deep necrobiosis lipoidica, morphea profunda and sclerosing panniculitis) and lobular-predominant pattern panniculitis (lupus erythematous panniculitis/lupus profundus, subcutaneous panniculitis-like T cell lymphoma, cutaneous γ-δ T cell lymphoma, Borrelia infection and cold panniculitis).

Pancreatic panniculitis in a patient with pancreatic-type acinar cell carcinoma of the liver--case report and review of literature

Background

Pancreatic panniculitis is a rare condition, which has only been described in relation with pancreatic diseases up to now. It is characterized by necrotizing subcutaneous inflammation and is thought to be triggered by adipocyte necrosis due to systemic release of pancreatic enzymes with consecutive infiltration of neutrophils. We present the first case of a patient with pancreatic panniculitis caused by pancreatic-type primary acinar cell carcinoma (ACC) of the liver and without underlying pancreatic disease.

Case presentation

A 73-year old Caucasian female patient was referred to our department with painful cutaneous nodules persisting for eight weeks and with marked lipasemia (~15000 U/l; normal range <60 U/l). Four weeks prior, several liver lesions had been detected. Empiric treatment with steroids did not show any effect. A biopsy of the skin nodules revealed “pancreatic” panniculitis, while abdominal imaging with ultrasound, computed tomography and magnetic resonance imaging detected no abnormal pancreatic findings. Ultrasound-guided biopsy of the liver lesions showed infiltrates of an ACC. The patient died soon thereafter. Autopsy failed to reveal any other primary for the ACC, so that a pancreatic-type ACC of the liver was diagnosed by exclusion.

One hundred thirty cases of pancreatic panniculitis published within the last 20 years are reviewed. ACC of the pancreas is the most common underlying neoplastic condition. Patients with associated neoplasm are significantly older, take longer to be diagnosed and have higher lipase levels than patients with underlying pancreatitis.

Extrapancreatic pancreatic-type ACC is very rare, but shows the same biological features as ACC of the pancreas. It is believed to develop from metaplastic or ectopic pancreatic tissue. Up to now, no pancreatic panniculitis in extrapancreatic ACC has been described.

Conclusion

Pancreatic panniculitis should always be included in the differential diagnosis of lipolytic panniculitic lesions. It can be regarded as a facultative paraneoplastic phenomenon.

When suspected, a thorough work-up for identification of the underlying disease is mandatory and extrapancreatic lesions (e.g. liver) should also be considered. While administration of octreotide or steroids can sometimes alleviate symptoms, immediate treatment of the associated condition is the only effective management option.