The "mystery" of cutaneous sarcoidosis: facts and controversies

Recent Clinical Studies on the Effects of Tumor Necrosis Factor-Alpha (TNF-α) and Janus Kinase/Signal Transducers and Activators of Transcription (JAK/STAT) Antibody Therapies in Refractory Cutaneous Sarcoidosis: A Systematic Review

The widely accepted standard of care for chronic cutaneous sarcoidosis is corticosteroids. However, when this treatment is shown to be refractory, other interventions must be considered. In this review, we report the current progress of clinical studies on various monoclonal antibody therapies and their future potential as primary interventions for refractory cutaneous sarcoidosis. In this systematic review, clinical studies on the management of refractory cutaneous sarcoidosis were retrieved from PubMed and ScienceDirect databases. Studies were screened based on article type, publication within the last 10 years, and access to free full text. The articles selected consisted of case studies, clinical trials, and observational studies. The studies needed to focus on cases of diagnosed cutaneous sarcoidosis at the time of the study and involve adult patients resistant to corticosteroid regimens, with or without additional immunomodulators. Only interventions that included tumor necrosis factor-alpha (TNF-α) (e.g., infliximab and adalimumab) or Janus kinase/signal transducers and activators of transcription (JAK/STAT) (e.g., ruxolitinib and tofacitinib) antibody therapy were considered. Two authors independently conducted quality assessments using the Joanna Briggs Institute Critical Appraisal and NIH Study Quality Assessment tools. A total of 16 clinical studies were included in this systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram. Of the 16 cases included, 15 studies demonstrated partial to complete resolution of cutaneous lesions within a range of two weeks to 18 months from initiation of antibody therapy. Studies on anti-TNF-α intervention demonstrated the most adverse events, including two deaths and one case associated with cutaneous exacerbation. Studies on anti-JAK-STAT interventions demonstrate no adverse events after treatment; however, patient study size was limiting. Recent studies have shown promising potential for anti-TNF-α and anti-JAK-STAT inhibitors to become the mainstay interventions in refractory cutaneous sarcoidosis. Due to limited population studies, the current data on the efficacy and safety of antibody therapies have not yielded a standardized FDA-approved steroid-sparing treatment. Therefore, a need for more population studies on the effectiveness of third-line intervention in refractory cutaneous sarcoidosis is necessary.

Sarcoidosis presenting as a loss of weight with preserved appetite

Sarcoidosis is a multisystem inflammatory disorder of unknown aetiology affecting a wide range of organs and is characterised by the presence of noncaseating granulomas. It has rarely been reported in Sri Lanka. This case describes a 36-year-old male presenting with a loss of weight despite a preserved appetite. He had evidence of sarcoidosis with pulmonary, lymph node, eye, hepatosplenomegaly, thyroid and parotid gland involvement with hypercalcaemia. He was successfully treated with glucocorticoids.

Clinical Features, Histopathology and Differential Diagnosis of Sarcoidosis

Sarcoidosis is a chameleon disease of unknown etiology, characterized by the growth of non-necrotizing and non-caseating granulomas and manifesting with clinical pictures that vary on the basis of the organs that are mainly affected. Lungs and intrathoracic lymph nodes are the sites that are most often involved, but virtually no organ is spared from this disease. Histopathology is distinctive but not pathognomonic, since the findings can be found also in other granulomatous disorders. The knowledge of these findings is important because it could be helpful to differentiate sarcoidosis from the other granulomatous-related diseases. This review aims at illustrating the main clinical and histopathological findings that could help clinicians in their routine clinical practice.

Propionibacterium acnes-Derived Circulating Immune Complexes in Sarcoidosis Patients

Propionibacterium acnes is a potential etiologic agent of sarcoidosis and a dysregulated immune response to the commensal bacterium is suspected to cause granuloma formation. P. acnes-derived insoluble immune complexes were recently demonstrated in sinus macrophages of sarcoidosis lymph nodes, suggesting local proliferation of the bacterium in affected organs. In the present study, we developed a method for detecting P. acnes-derived immune complexes in human blood by measuring the concentration of P. acnes-specific lipoteichoic acid (PLTA) detectable after an antigen retrieval pretreatment of plasma samples. Before pretreatment, anti-PLTA antibody was detected and PLTA could not be detected, in all plasma samples from 51 sarcoidosis patients and 35 healthy volunteers. After pretreatment, however, a significant level of PLTA (>105 ng/mL) was detected in 33 (65%) sarcoidosis patients and 5 (14%) control subjects, with 86% specificity and 65% sensitivity for sarcoidosis. In both groups, plasma anti-PLTA antibody titers did not differ between samples with and without detection of PLTA. PLTA levels were abnormally increased (>202 ng/mL) in 21 (41%) sarcoidosis patients. These findings suggest that P. acnes-derived circulating immune complexes present in human blood are abnormally increased in many sarcoidosis patients, presumably due to local proliferation of the bacterium in the affected organs.

Clinical Features and Diagnosis of Cardiac Sarcoidosis

Cardiac sarcoidosis (CS) is an unusual, but potentially harmful, manifestation of systemic sarcoidosis (SA), a chronic disease characterized by organ involvement from noncaseating and nonnecrotizing granulomas. Lungs and intrathoracic lymph nodes are usually the sites that are most frequently affected, but no organ is spared and CS can affect a variable portion of SA patients, up to 25% from post-mortem studies. The cardiovascular involvement is usually associated with a bad prognosis and is responsible for the major cause of death and complications, particularly in African American patients. Furthermore, the diagnosis is often complicated by the occurrence of non-specific clinical manifestations, which can mimic the effect of more common heart disorders, and imaging and biopsies are the most valid approach to avoid misdiagnosis. This narrative review summarizes the main clinical features of CS and imaging findings, particularly of CMR and 18-Fluorodeoxyglucose Positron Emission Tomography (18F-FDG PET) that can give the best cost/benefit ratio in terms of the diagnostic approach. Imaging can be very useful in replacing the endomyocardial biopsy in selected cases, to avoid unnecessary, and potentially dangerous, invasive maneuvers.

Chest Imaging of Patients with Sarcoidosis and SARS-CoV-2 Infection. Current Evidence and Clinical Perspectives

The recent COVID-19 pandemic has dramatically changed the world in the last months, leading to a serious global emergency related to a novel coronavirus infection that affects both sexes of all ages ubiquitously. Advanced age, cardiovascular comorbidity, and viral load have been hypothesized as some of the risk factors for severity, but their role in patients affected with other diseases, in particular immune disorders, such as sarcoidosis, and the specific interaction between these two diseases remains unclear. The two conditions might share similar imaging findings but have distinctive features that are here described. The recent development of complex imaging softwares, called deep learning techniques, opens new scenarios for the diagnosis and management.

Apremilast in dermatology: A review of literature

Apremilast is an orally administered small molecule that specifically inhibits the phosphodiesterase-4 enzyme and modulates the immune system by increasing the levels of intracellular cyclic adenosine monophosphate (cAMP) and inhibiting IL-2 & 8, interferon-γ and tumor necrosis factor (TNF) production. It is FDA approved for the treatment of psoriasis, psoriatic arthritis, and oral ulcers of Behcet's disease. More recently, apremilast has been used off-label to treat varied dermatological diseases where systemic corticosteroids or immunosuppressive agents were not effective. We review the efficacy and safety of apremilast in the treatment of aphthous stomatitis, Behçet's disease, chronic actinic dermatitis, atopic dermatitis, cutaneous sarcoidosis, hidradenitis suppurativa, lichen planus, and discoid lupus erythematosus in cases where standard treatment has failed.

CT Findings in Pulmonary and Abdominal Sarcoidosis. Implications for Diagnosis and Classification

Sarcoidosis is a granulomatous disorder of unknown etiology characterized by noncaseating granulomas virtually in every organ and tissue. This finding represents the most important diagnostic clue to reach a correct definition of sarcoidosis, although the biopsy is invasive and has several risk procedures. Several efforts are made to suspect the diagnosis of sarcoidosis by combining noninvasive elements, in particular from imaging, though these findings are often nonspecific and reflect the wide multifactorial pathogenesis. Every effort should be made to obtain a detailed radiological picture that, if associated with a suggestive clinical picture, could avoid the need of biopsy in some specific cases. In this narrative review, we aim to describe main computed tomography (CT) features of pulmonary and abdominal sarcoidosis, by reporting strengths and limits of this technique, in particular for the identification of extrapulmonary, isolated disease.

Immunocompromised Districts of Skin: A Case Series and a Literature Review

BACKGROUND

The concept of immunocompromised districts of skin has been developed by Ruocco and helps to explain certain aspects of the macromorphology of skin diseases. This concept unites the isomorphic response of Koebner and the isotopic response of Wolf.

CASE REPORTS

We present different cutaneous conditions which can lead to immunocompromised districts of skin such as scars, radiodermatitis, lymphedema, disturbed innervation or mechanical friction etc. Typical and rarer skin disorders associated with them are discussed and illustrated by their observations.

CONCLUSION

At this moment, we wish to inform dermatologists and non-dermatologists about Ruocco's concept and its implications.

Ultrasound imaging of abdominal sarcoidosis: State of the art

Since it has been recognized that sarcoidosis (SA) is not an exclusive disorder of the lungs but can also affect other organs such as the liver and spleen, efforts have been made to define specific imaging criteria for the diagnosis of the single organ involvement, and the concept has been reinforced that the exclusion of alternative causes is important to achieve the correct diagnosis. Ultrasound (US) is a useful tool to evaluate patients with suspected abdominal SA, such as of the liver, spleen, kidney, pancreas and other organs, showing findings such as organomegaly, focal lesions and lymphadenopathy. While the diagnosis of abdominal SA is more predictable in the case of involvement of other organs (e.g., lungs), the problem is more complex in the case of isolated abdominal SA. The recent use of contrast-enhanced ultrasound and endoscopic ultrasound elastography has provided additional information about the enhancement patterns and tissue rigidity in abdominal SA. Here we critically review the role of US in abdominal SA, reporting typical findings and limitations of current evidence and by discussing future perspectives of study.

[Enlarged mediastinal lymph nodes of a patient with malignant melanoma stage IV under pembrolizumab treatment]

A 40-year-old patient with malignant melanoma pT4bN0M1a stage IV (AJCC classification 2017) was treated with the PD-1/PD-L1 antibody pembrolizumab. Three months after treatment initiation the patient developed enlarged mediastinal lymph nodes despite the partial response of the cutaneous metastases. An elective lymph node extirpation was performed. The histopathological result was consistent with a sarcoid-like reaction. Treatment was discontinued and a pulse therapy with systemic steroids led to a significant remission of the lymphadenopathy. This side effect can manifest both during PD-1/PD-L1 antibody and CTLA-4 antibody therapy and should be included in the differential diagnosis of mediastinal lymphadenopathy.

Case Study: Cardiac sarcoidosis resolved with Mycobacterium avium paratuberculosis antibiotics (MAP)

Background: The author presents a clinical history and personal case study following his diagnosis of inactive sarcoidosis in 2004, followed by an acute episode of cardiac sarcoidosis (CS) in 2012 which resulted in complete heart block, cardiac myopathy, heart failure and insertion of an implantable cardioverter defibrillator (ICD) pacemaker. Methods: Following a detailed review of the clinical and scientific literature he concluded that sarcoidosis may be a mycobacterial infection and could be treated with anti-MAP antibiotic regime (1) developed to treat Crohn's disease. Findings: After successful culture and identification of viable MAP in his blood, treatment with the MAP antibiotic regime for one year led to complete metabolic resolution of the previously avid cardiac sarcoidosis and no PET evidence of any metabolically active sarcoidosis anywhere. Such reversal of cardiac sarcoidosis has never previously been reported. (Sarcoidosis Vasc Diffuse Lung Dis 2018; 35: 171-177).

Sarcoidosis in A. C. Milan (1899)?

The pathogenesis, diagnosis and therapy of sarcoidosis as an autonomous disease are subjects of spirited discussions, which haven’t found definitive conclusion yet. Distinguishing between sarcoidosis and sarcoid-like reactions (sarcoid - type granulomas) is not currently a medical “gold standard” and is not implemented in clinical practice. This leads to 1) misinterpretation of numerous available data; 2) difficulty in the interpretation of other unverified data, which is often followed by 3) inappropriate or inadequate therapeutic approach. Similarly to many other diseases, in sarcoidosis and sarcoid - types of reactions the concept of personalised approach and therapy should also be introduced. This methodology of clinical guidance is difficult, complex and not always achievable in the current medical status and relations (doctor-patient relationship; financial factor; time factor). It is appropriate to note that in some cases the guidelines or the so-called standards are neglected or not possible to put into practice with the aim of better therapeutic practices and strategies, as well as the achievement of optimal final clinical results (especially in patients with sarcoid granulomas). The sarcoid granuloma, even when it is sterile, should not be considered as the equivalent of sarcoidosis, i.e., sarcoidosis as an autonomous disease. Sure enough, exactly because of this fact, the personalised approach should not be an exception, but it has to gradually become a rule in medical practice. When clinical decisions are conformed to some of the latest modern concepts, officialised in the international databases, often the achieved results can be much better.

We present a patient with a tattoo of AC Milan (1899) on his right arm, who subsequently developed localised sterile sarcoid granulomas in the area of the tattoo. Later the process became generalised on his whole body’s skin, lungs and lymph nodes. It is unclear for the moment whether this condition should be interpreted as sarcoidosis as an autonomous disease or, instead, as a sarcoidal type of reaction with subsequent generalisation due to cross-reactivity against antigens present in other tissues with similarities to the exogenous pigments. Following the modern concepts regarding the pathogenesis of these two conditions, we introduced, in this case, an innovative, non-standard approach: 1) systemic and local immunosuppressive therapy, combined with 2) recommеndation for immediate surgical excision of the tattoo to remove the possible trigger of molecular and antigen mimicry.

Multisystemic Sarcoidosis Presenting as Pretibial Leg Ulcers

Sarcoidosis is a multisystemic disease of unknown etiology. Up to 30% of patients develop cutaneous manifestations, either specific or nonspecific. Ulcerating sarcoidosis leading to leg ulcers is a rare observation that may lead to confusions with other, more common types of chronic leg ulcers. We report the case of a 45-year-old female patient with chronic multisystemic sarcoidosis presenting with pretibial leg ulcers. Other etiology could be excluded. Histology revealed nonspecific findings. Therefore, the diagnosis of nonspecific leg ulcers in sarcoidosis was confirmed. Treatment consisted of oral prednisolone and good ulcer care. Complete healing was achieved within 6 months. Sarcoidosis is a rare cause of leg ulcers and usually sarcoid granulomas can be found. Our patient illustrates that even in the absence of sarcoid granulomas, leg ulcers can be due to sarcoidosis.

Sarcoidosis in Melanoma Patients: Case Report and Literature Review

Sarcoidosis is a systemic inflammatory disease characterized by the development of noncaseating granulomas in multiple organ systems. Many hematologic malignancies and solid tumors, including melanoma, have been associated with sarcoidosis. We describe the clinical and pathologic findings of a 54-year-old man with melanoma-associated sarcoidosis. In addition, we not only review the literature describing characteristics of other melanoma patients with sarcoidosis, but also the features of melanoma patients with antineoplastic therapy-associated sarcoidosis. Sarcoidosis has been described in 80 melanoma patients; sufficient information for analysis was provided in 39 of these individuals. In 43.6% of individuals (17 out of 39), sarcoidosis was directly associated with melanoma; in 56.4% of oncologic patients (22 out of 39), sarcoidosis was induced by antineoplastic therapy that had been administered for the treatment of their metastatic melanoma. The discovery of melanoma preceded the development of sarcoidosis in 12 of the 17 (70.5%) individuals who did not receive systemic treatment. Pulmonary and/or cutaneous manifestations of sarcoidosis were common among both groups of patients. Most patients did not require treatment for sarcoidosis. Melanoma patients—either following antineoplastic therapy or without systemic treatment—may be at an increased risk to develop sarcoidosis. In antineoplastic therapy naive melanoma patients, a common etiologic factor—such as exposure to ultraviolet light—may play a role in their developing melanoma and sarcoidosis.

Perineural granulomas in cutaneous sarcoidosis may be associated with sarcoidosis small-fiber neuropathy

Perineural granulomas in cutaneous sarcoidosis have been rarely reported and their clinical significance has yet to be evaluated. Recently, a 27-year-old male presented with multiple pink papules on the flank and lower back, accompanied by a painful, burning sensation. Biopsies revealed well-defined granulomas, consistent with sarcoidosis, in the dermis and involving small cutaneous nerves. We hypothesized that perineural granulomas may be an under-recognized feature of cutaneous sarcoidosis and may be responsible for sensory disturbances. We reviewed cases from 29 consecutive patients with cutaneous sarcoidosis. Perineural granulomas were identified in 18/29 (62%) patients and in 22/40 (55%) biopsies. Perineural granulomas were identified in 7/9 biopsies from the proximal upper extremity, 1/3 from the distal upper extremity, 7/12 from the head and the neck, including 4/4 from the nose, 5/9 from the back, 1/2 from the flank and 1/1 from the proximal lower extremity and 0/4 from the distal lower extremity. The anatomical distribution is similar to sarcoidosis small-fiber neuropathy (SSFN), in which sarcoidosis patients without evident skin lesions experience sensory disturbances of unknown etiology involving the face, the proximal extremities and the trunk. Our results indicate perineural granulomas in cutaneous sarcoidosis are more common than previously appreciated, primarily involve the head, the proximal upper extremities and the back, and may be responsible for neurological manifestations.

Non-infectious granulomatous conditions of the skin: a clinicopathological approach to diagnosis

Granulomatous disorders of the skin are diverse and include infectious and non-infectious conditions. They are a source of confusion to many dermatologists and pathologists, including even the most experienced dermatopathologists. Correlation with clinical picture, serology, microbiology and careful morphological examination is essential for accurate diagnosis. Most cases require ancillary histopathological studies to reach a final diagnosis. This review discusses important non-infectious granulomatous conditions of the skin and presents a practical approach when confronted with such entities.

Challenges in the diagnosis and treatment of neurosarcoidosis

The diagnosis and treatment of neurosarcoidosis can be very challenging for several reasons. It affects clinically 5%-10% of sarcoidosis patients, but can be found in up to 25% of autopsies. These data reveal that a high percentage of asymptomatic or misdiagnosed cases can be missed at an initial diagnostic approach. Clinical and imaging findings are often non-specific since they can be found in a large number of neurological disorders. Histopathology can also be confounding if not performed by an expert pathologist and not placed in an appropriate clinical context. In this review, we discuss clinical features, laboratory findings, imaging, and histology of neurosarcoidosis, and we report current evidence regarding drug therapy. We conclude that a correct diagnostic approach should include a multidisciplinary evaluation involving clinicians, radiologists, and pathologists and that future studies should evaluate the genetic signature of neurosarcoidosis as they could be helpful in the assessment of this uncommon disease. With head-to-head comparisons of medical treatment for neurosarcoidosis still lacking due to the rarity of the disease and an increasing number of immunomodulating therapies at hand, novel therapeutic approaches are to be expected within the next few years.