Panniculitis: A summary

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.

Dermatomyositis with Eosinophils

Dermatomyositis is an idiopathic inflammatory myopathy that often presents with symmetric proximal skeletal muscle weakness and characteristic skin findings. Typical skin biopsy findings include vacuolar changes of the basal layer, increased dermal mucin, and a predominantly lymphocytic infiltrate. We report a case of dermatomyositis presenting as intensely pruritic papules and plaques, with initial histopathology being atypical of dermatomyositis due to the presence of eosinophils. The initial biopsy demonstrated a superficial dermatitis with eosinophils, initially thought to represent a drug eruption. A second biopsy of the same cutaneous manifestation was performed at a later time given high clinical suspicion for dermatomyositis and demonstrated a more classic vacuolar interface dermatitis with increased mucin and an absence of eosinophils. Notably, increased pruritus was specifically associated with the lesion that demonstrated tissue eosinophilia. The case illustrates the importance of considering tissue eosinophilia in the histologic presentation of dermatomyositis.

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.

Suggestions for a New Clinical Classification Approach to Panniculitis Based on a Mayo Clinic Experience of 207 Cases

BACKGROUND

Panniculitis, or inflammation of adipose tissue, includes a heterogeneous group of disorders with similar morphologic presentations. Currently, panniculitides are classified based on histopathologic findings only.

OBJECTIVE

In this retrospective study of 207 cases of biopsy-proven panniculitis over 20 years at Mayo Clinic, we aimed to propose a new classification that integrates the clinical morphologic features with the histopathology of panniculitis.

METHODS

We collected patient demographic and lesion morphologic characteristics using lesion photographs and physician notes for each of our 207 cases, including location, ulceration, scale, pattern (unilateral versus circumferential), atrophy/sclerosis (cicatricial), redness, and swelling.

RESULTS

The panniculitides most likely to ulcerate were calciphylaxis (85.7% ulcerating), pancreatic panniculitis (66.6%), and α₁-antitrypsin deficiency-associated panniculitis (100%). The panniculitides least likely to ulcerate were erythema nodosum and medication-induced and granulomatous panniculitis. This retrospective study used only descriptions in clinical notes and available medical photographs.

CONCLUSION

We present an updated classification schema of panniculitides based on clinical findings. The primary distinctions are based on ulceration, location, and number of lesions. Although complete distinction of all panniculitides based on clinical examination alone is not possible, we hope the proposed schema allows clinicians to tailor differential diagnoses.

Subcutaneous panniculitis-like T-cell lymphoma in a young girl presenting with periorbital edema and fever: A case report

Subcutaneous panniculitis-like T-cell lymphoma is a rare and highly malignant extra-nodal lymphoma. It has a wide range of clinical presentations (such as periorbital swelling as in our case) and should be considered in the differential diagnosis of systemic lupus erythematosus, especially in children.

Revisiting the question of cutaneous vasculitis classification

Currently, there is no generally accepted terminology and classification of vasculitis and vascular cutaneous disorders. In Russia there are various approaches to the classification of cutaneous vasculitis vascular lesions are classified according to clinical signs, etiology and pathogenesis. Significant difficulties are caused by the lack of a unified terminology, clear diagnostic criteria for vasculitis and the existence of a large number of duplicate names, among which there are many eponymous terms. This issue is one of the most complex, confusing and debatable not only in dermatovenereology, but also in other disciplines. Modern principles of diagnosis of cutaneous vasculitis are based on an integrated assessment of the data of the disease history, clinical picture, laboratory and instrumental methods of examination. For standardization of definitions and diagnostic criteria, it is necessary, first of all, to adopt a unified interdisciplinary classification of vasculitis, which will be based on the etiopathogenetic principle. The applied unified classification of cutaneous vasculitis is proposed for discussion.

Neutrophilic Infiltrates in Panniculitis: Comprehensive Review and Diagnostic Algorithm Proposal

Neutrophilic infiltrates in panniculitis can be seen in different clinical-pathological entities. There are a "mostly neutrophilic inflammatory infiltrate" in some entities classically defined as neutrophilic panniculitis and already included in algorithms, such as enzymatic panniculitis, infective and factitial ones, erythema induratum, or subcutaneous Sweet syndrome, but there are also other panniculitis where neutrophils are frequently observed such as panniculitis associated with inflammatory bowel disease or rheumatoid arthritis, or drug-induced panniculitis associated with BRAF inhibitors, and finally, some panniculitis are better classified in other panniculitides groups but may present with neutrophil-rich variants, such as the neutrophil-rich subcutaneous fat necrosis of the newborn. We review the main clinical and histopathological features of most of these panniculitides and construct a diagnostic algorithm including these diseases.

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.

Erythema Nodosum: A Practical Approach and Diagnostic Algorithm

Erythema nodosum is the most common form of panniculitis and is characterized by tender erythematous nodules mainly in the lower limbs on the pretibial area. The exact cause of erythema nodosum is unknown, although it appears to be a hypersensitivity response to a variety of antigenic stimuli. Although the etiology is mostly idiopathic, ruling out an underlying disease is imperative before diagnosing primary erythema nodosum. Erythema nodosum can be the first sign of a systemic disease that is triggered by a large group of processes, such as infections, inflammatory diseases, neoplasia, and/or drugs. The most common identifiable causes are streptococcal infections, primary tuberculosis, sarcoidosis, Behçet disease, inflammatory bowel disease, drugs, and pregnancy. We propose a diagnostic algorithm to optimize the initial work-up, hence initiating prompt and accurate management of the underlying disease. The algorithm includes an initial assessment of core symptoms, diagnostic work-up, differential diagnosis, and recommended therapies. Several treatment options for the erythema nodosum lesions have been previously reported; nevertheless, these options treat the symptoms, but not the triggering cause. Making an accurate diagnosis will allow the physician to treat the underlying cause and determine an optimal therapeutic strategy.

Ponatinib-associated panniculitis: Case report and review of the literature

Ponatinib is a tyrosine kinase inhibitor (TKI) approved for the treatment of Philadelphia chromosome-positive chronic myelogenous leukemia and acute lymphoblastic leukemia. Common adverse effects of ponatinib include neutropenia, arterial thrombosis, and hypertension. We describe a 49-year-old woman who developed panniculitis after brief treatment with ponatinib. In addition, we summarize other studies describing TKI-associated panniculitis.

Alpha-1 antitrypsin deficiency-associated panniculitis

BACKGROUND

Panniculitis represents a rare and potentially lethal manifestation of alpha-1 antitrypsin deficiency (AATD). Evidence regarding management is limited to case reports and small case series. We sought to clarify typical features and investigation of AATD-associated panniculitis and assess the evidence regarding therapeutic options.

SEARCH METHODOLOGY

Articles and abstracts published between 1970 and 2020 were identified by searches of MEDLINE, PubMed, and secondary searches of references from relevant articles using the search terms "panniculitis," "alpha-1," "antitrypsin," "deficiency," and "Weber-Christian."

FINDINGS

We identified 117 cases of AATD-associated panniculitis. In 1 series, AATD was present in 15% of all cases of biopsy-proven panniculitis. Failure to achieve clinical response was seen in all instances of systemic steroid use. Dapsone, although effective and accessible, is frequently associated with failure to achieve remission. In these instances, intravenous AAT augmentation therapy generally resulted in response.

CONCLUSIONS

AATD may be more prevalent among patients presenting with panniculitis than previously thought. Patients presenting with panniculitis and systemic illness show high mortality risk. Although most cases are associated with the severe ZZ-genotype, moderate genotypes may also predispose to panniculitis. Dapsone remains the most cost-effective therapeutic option, whereas intravenous AAT augmentation remains the most efficacious. Finally, glucocorticoids appear ineffective in this setting.

Intravenous Immune Globulin (IVIG) Therapy After Unsuccessful Treatment with Corticosteroid and Cyclosporine A in Pfeifer-Weber-Christian Disease: A Case Report

BACKGROUND Pfeifer-Weber-Christian disease (PWCD), also referred to as idiopathic nodular panniculitis, is a rare idiopathic disease characterized by lobular panniculitis of adipose tissue with systemic symptoms and multiple organ involvement and is usually treated with corticosteroids and cyclosporine A. We report a case of PWCD that was unresponsive to standard treatment but responded to intravenous immune globulin (IVIG) therapy. CASE REPORT A 35-year-old Korean woman presented with fever, malaise, myalgia, and painful nodules in the left breast. Histology of the breast nodules showed lobular panniculitis consistent with PWCD. She did not respond to corticosteroid and cyclosporine A. She was effectively treated with intravenous immune globulin (IVIG). IVIG therapy began with 60 g (1 g/kg) 4 times per week, 2 times every other week. Subsequently, the IVIG dose was reduced for maintenance therapy to 25 g (400 mg/kg) twice every other week and monthly. The patient showed immediate and dramatic improvement. General signs and symptoms, such as fever, malaise, and myalgia, were absent, and the masses had nearly subsided, with several very small hard nodules remaining for 3 months until the time of this report. CONCLUSIONS IVIG was an effective immunomodulatory therapeutic for PWCD in this case. This report shows that PWCD is a rare condition that is difficult to diagnose, but the histopathology of nodular panniculitis supports the diagnosis. In cases that do not respond to standard immunosuppressive therapy, including corticosteroids and cyclosporine A, IVIG therapy may lead to a favorable response with rapid symptomatic relief.

Lipoatrophic panniculitis of children

Idiopathic lipoatrophic panniculitis of children is a rare disease of childhood, characterized by repeated attacks of tender subcutaneous nodules followed by the development of permanent lipoatrophy, often seen on the arms and legs, in association with fever, malaise, and other less common clinical manifestations such as abdominal pain or arthralgia. The pathogenesis is unknown, and autoimmune origins, chromosomal alterations, and other causes have been proposed. The nosology of this condition is confusing in the literature, and the precise diagnosis still relies on a combination of clinicopathologic and laboratory assessments. Methotrexate may be recommended to minimize disease progression and morbidity.

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.

Neutrophilic panniculitis arising from hematogenous spread of methicillin-resistant Staphylococcus aureus

Infectious panniculitis from hematogenous spread is uncommon and usually occurs in immunocompromised patients. Dissemination of gram-positive organisms to the subcutaneous tissue is rare with only several reports of disseminated panniculitis caused by Streptococcal species. We report a case of an immunocompetent 2-year-old boy presenting with diffuse neutrophilic panniculitis arising from methicillin-resistant Staphylococcus aureus septicemia. This case represents a highly atypical manifestation of severe MRSA infection and serves as a reminder to consider MRSA as a cause of disseminated neutrophilic panniculitis, particularly in high-risk populations.

Common and critical inflammatory dermatoses every pathologist should know

Inflammatory dermatopathology remains a challenging area for surgical pathologists. Yet every surgical pathologist encounters inflammatory dermatoses as part of routine practice. This review will focus on selected diagnoses that are either commonly encountered in the routine practice of surgical pathology or are critically important. The following entities will be covered: spongiotic dermatoses, lichen simplex chronicus, and early lichen sclerosus in the setting of vulvar biopsies, as well as graft versus host disease, Stevens-Johnson syndrome/toxic epidermal necrolysis, granuloma anulare, pyoderma gangrenosum, and calciphylaxis. Practical points and key histologic features will be emphasized.

[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.

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.