Granuloma Annulare: a Case-control Study of Possible Associated Diseases.

Introduction: Granuloma annulare (GA) has been reported as associated with multiple diseases, mainly diabetes mellitus (DM), thyroid diseases, and dyslipidemia. However, the high prevalence of some of these illnesses makes it difficult to assess whether the association is real or fortuitous. Objectives: Our objective was to analyze the clinical features of GA patients and the possible associations. Methods: This is a retrospective observational study of 225 patients with biopsy-proven GA diagnosed between 2009 and 2019 in a referral university hospital in Barcelona, Spain. Clinical charts were reviewed to obtain clinical data. As a control group we used a random list of 225 patients diagnosed in the hospital traumatology department in the same period, matched by age and sex. Results: Diabetes was diagnosed in 40 GA patients (18%) (34 in the control group, 15%) and hypothyroidism in 33 (15%) (22 in the control group 9.8%); the differences were not significant. We also did not detect any association with uveitis, sarcoidosis, necrobiosis lipoidica, Sweet syndrome, HIV infection, hepatitis B, or hematological malignancies. We only detected a possible association with hepatitis C (6 GA patients, 2.7%, versus 0 controls, P = 0.03), and hypercholesterolemia (108 GA patients, 48%, versus 79 controls, 35%, P = 0.007). Conclusions: The possible pathogenic explanations for the association with hepatitis C and hypercholesterolemia seem unlikely. We consider that the association of GA with other diseases, including hypercholesterolemia and hepatitis C, is doubtful and that it there is no justification rule out possible associated diseases in patients with GA.

Multiple Drug Regimen-Refractory Rosai-Dorfman-Destombes Disease Mimicking Relapsing Polychondritis Successfully Treated with Cobimetinib.

Rosai-Dorfman-Destombes disease (RDD) or sinus histiocytosis with massive lymphadenopathy is a rare non-Langerhans cell histiocytosis of unknown cause. The disease often manifests as painless bilateral cervical lymphadenopathy associated with systemic symptoms such as fever and weight loss. Extranodal disease is also frequent and can involve any organ, mostly the skin, nasal cavity, bone, and retro-orbital tissue. Swelling of cartilaginous tissues, such as the helix of the ear or laryngeal structures, may mimic the entity known as relapsing polychondritis. Although spontaneous remission is the most expected evolution, some cases require systemic treatment with prednisone, methotrexate or cytotoxic agents, with variable rates of success. In this respect, since somatic variants in the genes involved in the mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinases (ERK) pathway have been observed to play a pathogenic role in RDD. Therefore, the use of therapies targeting these pathogenic variants appears to be a reasonable strategy. Here we present the case of a 37-year-old woman with RDD and extensive extranodal involvement that showed a rapid and complete response to the MEK inhibitor cobimetinib. LEARNING POINTS: Rosai-Dorfman-Destombes disease (RDD) may mimic the entity known as relapsing polychondritis but should be treated with drug therapy for the underlying disease.Mutations in MAPK/ERK pathway components should be determined in RDD with systemic involvement, although testing to determine every somatic mutation responsible for the disease is not available in all healthcare centres.MEK inhibitors like cobimetinib could be effective in RDD cases with severe and refractory systemic disease, even if molecular analysis has not been possible.

[Granulomatous mastitis associated with erythema nodosum: A case series of 42 patients]. / Mastitis granulomatosa asociada a eritema nudoso: estudio de 42 casos.

BACKGROUND: Granulomatous mastitis (GM) is defined by the formation of granulomatous inflammation in breast tissue. Erythema nodosum (EN) is a reactive inflammatory panniculitis characterized by erythematous subcutaneous nodules in the lower limbs. The association of GM with EN has been rarely reported. Our aim was to retrospectively review our series of patients with GM to better characterize their features and their association with EN. METHODS: Cases histologically diagnosed as granulomatous inflammation in breast tissue between 1995 and 2020 were retrospectively reviewed. RESULTS: Forty-two women were diagnosed with GM. The average age at diagnosis was 41.619years, and 59.5% were of South-American ethnicity. EN was associated with GM in 11.9% of the patients. Patients with EN were diagnosed earlier than isolated GM (0.4months vs 6.81months; P<.05). Ulceration in the GM was more prevalent in patients with associated EN (60% vs 14.7%; P<.05). CONCLUSION: EN in patients with GM may reduce the evolution time and may help to diagnose this rare condition that mimics breast carcinoma.

Cutaneous Leiomyoma: A Clinical Study of 152 Patients.

BACKGROUND: Cutaneous leiomyoma (CL) is a benign smooth muscle tumour included in painful skin tumours. Multiple CLs are cutaneous markers of hereditary leiomyomatosis and renal cell cancer (HLRCC). OBJECTIVES: To retrospectively review our series of patients with CLs to analyse their clinical features and the association with HLRCC. METHODS: Cases coded as CL in the database of the pathology department between 2004 and 2019 were included in the study. Medical records were retrospectively reviewed to obtain the following data: age, sex, location, number of lesions, diameter, evolution time at diagnosis, suspected clinical diagnosis, tenderness, status of resection margins, development of recurrence, follow-up time, and association with HLRCC. RESULTS: 152 patients had CLs, 89 women and 63 men, mean age 56.26, SD 16.030 years. Subtypes were piloleiomyoma in 62 patients, angioleiomyoma in 80, and genital leiomyoma in 10. All of our 11 patients with multiple lesions corresponded to piloleiomyomas, and HLRCC was confirmed in 8 of them (73%). Patients with HLRCC were younger than patients with piloleiomyomas without HLRCC (34.88 vs. 56.17 years, p = 0.009). Vascular and genital leiomyomyomas were solitary and were not associated with HLRCC. CONCLUSION: In patients with multiple piloleiomyomas HLRCC must be ruled out as it is confirmed in a high proportion of cases. The probability of fumarate hydratase mutation is greater in multiple piloleiomyomas involving both the trunk and upper extremities in the same patient.

Sarcoidosis Induced by Atezolizumab Presenting With Xanthelasma Infiltration.

ABSTRACT: Sarcoidosis induced by anti-PD1 or anti-PDL1 agents such as atezolizumab has recently been reported. It has been suggested that the predilection of sarcoidosis to affect scars is due to the presence of antigens or foreign bodies that can serve as a stimulus for granuloma formation. However, to the best of our knowledge, sarcoidosis-specific skin lesions have not to date been reported involving xanthelasma. We report a patient who developed specific lesions of sarcoidosis infiltrating some xanthelasmata 6 months after starting treatment with atezolizumab. A 69-year-old woman was referred to the dermatology department for infiltration of xanthelasmata. The patient was being treated with atezolizumab for metastatic uterine carcinosarcoma. Cutaneous biopsy from an infiltrated xanthelasma and from still yellow, no infiltrated xanthelasma showed differing proportions of foamy histiocytes and sarcoid granulomas. On physical examination, erythemato-marronaceous papules clustered on both knees, and not previously detected by the patient, were observed. The biopsy showed sarcoid dermal granulomas with foreign bodies. A chest computerized tomography scan was consistent with intrathoracic involvement of sarcoidosis. Endobronchial ultrasound-guided transbronchial needle aspiration of a mediastinal lymphadenopathy showed epithelioid cell granulomas. Histopathologically, the foamy histiocytes of xanthelasma seem to be replaced by or evolve to epithelioid cells to form sarcoid granulomas. The possible pathogenic mechanism is discussed. Dermatologists and dermatopathologists should bear in mind that sarcoidosis can present as infiltration of pre-existing xanthelasmata.