Oral Focal Mucinosis of the Tongue: A Rare Localization for a Rare Entity.

ABSTRACT: Oral focal mucinosis (OFM) is a rare connective tissue disorder that is characterized by the excessive production of hyaluronic acid due to myxoid degeneration of submucosal connective tissue. The disorder typically presents as an asymptomatic nodule or mass in the gingiva or hard palate, and OFM of the tongue is even more unusual. In this report, we present a case of OFM on the tongue in a 72-year-old female patient who presented with a symptomatic lump that had been growing for 6 months on the dorsum of her tongue. The patient reported discomfort and pain while speaking and swallowing, and the lump was visually apparent on examination. OFM is a benign condition that does not have any specific clinical or radiographical features that distinguish it from other more common oral lesions, such as lipoma or fibroma. Therefore, histopathological examination is essential for a definitive diagnosis. The management of OFM typically involves surgical excision of the lesion. In this case, complete surgical removal of the lesion under general anesthesia was performed, and the patient was followed up for 10 months postoperatively. During the follow-up period, there was no evidence of recurrence, and the patient reported significant improvement in her symptoms. In conclusion, OFM is a rare connective tissue disorder that can occur in the oral cavity. Although OFM of the tongue is even rarer, it should be considered in the differential diagnosis of oral lesions. Histopathological examination is essential for definitive diagnosis, and surgical excision is typically the preferred treatment modality.

Self-Healing Juvenile Cutaneous Mucinosis: A Report of Two Cases With Differing Evolution.

ABSTRACT: Self-healing juvenile cutaneous mucinosis is a rare entity, characterized by the presence of subcutaneous nodules together with frequent nonspecific systemic symptoms, which occurs in the pediatric age and characteristically resolves spontaneously. Although the diagnostic criteria do not require a biopsy to be performed, it is frequently performed, and an abundant dermal mucin deposition will be observed together with other features such as fibroblastic proliferation. Although the prognosis is benign, follow-up is required for the eventual development of a rheumatologic disease.We present 2 clinical cases, describing the clinical findings and their histopathologic correlation. Comparatively, the outcome in both cases was different: in one case, the mucinosis resolved without any related event in the follow-up, and in the other case, the resolution was accompanied by the subsequent development of idiopathic juvenile arthritis.

Identifying the potential origin of mucin in primary cutaneous mucinoses-A retrospective study and analysis using histopathology and multiplex fluorescence staining.

BACKGROUND: Primary cutaneous mucinoses (PCM) are rare diseases characterized by dermal or follicular mucin deposits. OBJECTIVES: A retrospective study characterizing PCM to compare dermal with follicular mucin to identify its potential origin on a single-cell level. MATERIAL AND METHODS: Patients diagnosed with PCM between 2010 and 2020 at our department were included in this study. Biopsy specimens were stained using conventional mucin stains (Alcian blue, PAS) and MUC1 immunohistochemical staining. Multiplex fluorescence staining (MFS) was used to investigate which cells were associated with MUC1 expression in select cases. RESULTS: Thirty-one patients with PCM were included, 14 with follicular mucinosis (FM), 8 with reticular erythematous mucinosis, 2 with scleredema, 6 with pretibial myxedema and one patient with lichen myxedematosus. In all 31 specimens, mucin stained positive for Alcian blue and negative for PAS. In FM, mucin deposition was exclusively found in hair follicles and sebaceous glands. None of the other entities showed mucin deposits in follicular epithelial structures. Using MFS, all cases showed CD4+ and CD8+ T cells, tissue histiocytes, fibroblasts and pan-cytokeratin+ cells. These cells expressed MUC1 at different intensities. MUC1 expression in tissue histiocytes, fibroblasts, CD4+ and CD8+ T cells, and follicular epithelial cells of FM was significantly higher than the same cell types in the dermal mucinoses (p < 0.001). CD8+ T cells were significantly more involved in expression of MUC1 than all other analysed cell types in FM. This finding was also significant in comparison with dermal mucinoses. CONCLUSION: Various cell types seem to contribute to mucin production in PCM. Using MFS, we showed that CD8+ T cells seem to be more involved in the production of mucin in FM than in dermal mucinoses, which could indicate that mucin in dermal and follicular epithelial mucinoses have different origins.

Intestinal Submucosal Mucinosis in a Patient With Systemic Lupus Erythematosus: A Case Report.

Systemic lupus erythematosus (SLE) is an autoimmune disease with various clinical presentations. Mucin deposition is a characteristic finding in skin lesions, but it is rare in other organs. We present a case with erythematous patches from the terminal ileum to the anus in an SLE patient. Diffuse colitis was diagnosed clinically. However, in addition to inflammatory cell infiltration, there was abundant mucinous material deposition in the submucosa. The mucinous material was positive for Alcian blue staining (pH 2.5) and was sensitive to hyaluronidase digestion. These findings are similar to those of cutaneous mucinosis in SLE patients. This is thought to be the first case of gastrointestinal tract mucinosis in SLE reported in the literature.

New and emerging conditions of acquired cutaneous mucinoses in adults.

Cutaneous mucinoses are a heterogenous group of conditions, characterized by the deposition of glycosaminoglycans (mucin) in the dermis, follicles, or in the epidermis. Major cutaneous mucinoses include lichen myxedematosus, scleredema, mucinoses associated with thyroid disease, reticular erythematous mucinosis, papulonodular mucinosis associated with connective tissue diseases, and cutaneous focal mucinosis. The aim of this review is to provide an update of what has currently been reported in the last 30-year literature about several new or emerging conditions of acquired cutaneous mucinoses in adults. Two new clinico-pathologic entities have been described: (i) Obesity-associated lymphedematous mucinosis and pretibial stasis mucinosis; (OACM) (ii) Nodular mucinosis of the breast (NMB). Two relatively new disease categories encompassing cutaneous mucinoses with a common pathogenetic mechanism have been identified: (i) Cutaneous mucinoses associated with drug exposure including biologic therapy, anti-colony-stimulating factor 1 receptor (CSF1R) and subcutaneous intralesional interferons (toxic dermal mucinoses); (ii) Cutaneous mucinosis following physical agents including mechanical traumas and after knee replacement.

Acute acral eruptions in children during the COVID-19 pandemic: Characteristics of 103 children and their family clusters.

BACKGROUND: A marked increase in frequency of acute acral eruptions (AAE) was observed in children during the COVID-19 pandemic in the spring period. OBJECTIVES: In this observational multicenter study, based on children with AAE, we aimed to assess the proportion of household members possibly infected by SARS-CoV-2. METHODS: We collected data from all children observed with AAE, prospectively from April 7, 2020 to June 22, 2020, and retrospectively since February 28, 2020. The primary outcome was the household infection rate, defined as the proportion of family clusters having at least one member with COVID-19 infection other than the child with AAE ("index child"). The definition of a case was based on characteristic clinical signs and a positive PCR or serology. RESULTS: The study included 103 children in 10 French departments and in Quebec. The median age was 13 years and the interquartile range [8-15], with a female-to-male ratio of 1/1.15. In children with AAE, all PCR tests were negative (n=18), and serology was positive in 2/14 (14.3%) cases. We found no significant anomalies in the lab results. A total of 66 of the 103 families (64.1%) of included children had at least one other infected member apart from the index child. The total number of household members was 292, of whom 119 (40.8%) were considered possibly infected by SARS-CoV-2. No index children or households exhibited severe COVID-19. DISCUSSION: Among the 103 households included, 64.1% had at least one infected member. Neither children with AAE nor their households showed severe COVID-19.

Case report and review of solitary cutaneous focal mucinosis: a unique primary cutaneous mucinosis unrelated to mucinosis-associated systemic diseases.

Localized deposition of mucin in the upper dermis is referred to as cutaneous focal mucinosis. Patients with this condition either present with a single skin lesion (solitary cutaneous focal mucinosis) or numerous skin lesions (multiple cutaneous focal mucinosis). A man with solitary cutaneous focal mucinosis is described and the features of this condition are reviewed. Solitary cutaneous focal mucinosis has a slight male predominance and typically presents in adults, ranging in age from 29 years to 60 years, as a nodule or papule that is flesh-colored or white and most commonly located on an extremity or the trunk. Microscopic examination shows deposition of mucin in the upper dermis; the overlying epidermis can be normal, atrophic or hyperplastic. The skin lesion is often removed at the time of biopsy. However, recurrence has not been observed when the mucin deposition is present at the edge of the biopsy or excision specimen. Although the pathogenesis of this condition remains to be established, in contrast to individuals with multiple cutaneous focal mucinosis, solitary cutaneous focal mucinosis is a unique primary cutaneous mucinosis unrelated to mucinosis-associated systemic diseases.

Myofibroblast phagocytic cutaneous mucinosis: phagocytosis of mucinous substances by myofibroblasts in a distinctive cutaneous mucinosis: A case report.

RATIONALE: Phagocytosis is an important physiological process for eliminating unnecessary substances or dead cells after tissue damage, such as inflammation or infarction. Phagocytosis was previously considered to be mainly performed by professional phagocytotic cells, such as macrophages. In contrast, we previously demonstrated that the phagocytosis of dead cells and unnecessary substances by myofibroblasts is as important as that by professional phagocytotic cells in myocardial infarction. Based on our discovery, we speculated that phagocytosis by myofibroblasts may be a more common pathological phenomenon also in other diseases than previously believed. PATIENT CONCERNS: A 44-year-old male patient with atopic dermatitis developed a cutaneous reddish nodule with an underlying induration on his thigh. INTERVENTIONS: The cutaneous lesion was surgically removed. DIAGNOSES: Histopathological examination demonstrated that the cutaneous lesion had solid infiltration by inflammatory cells, namely, plasma cells, histiocytes, and lymphocytes, in the dermis. The cutaneous lesion included mucinosis in the dermis. Inside the mucinosis, we detected cells with clear areas of mucinous substances. Some of the cells were α-smooth muscle actin-positive myofibroblasts. Electron microscopic images demonstrated that there were collagen bands in the cells with mucinous engulfment. Based on these pieces of evidence, we conclude that these mucinous phagocytotic cells were myofibroblasts, not professional phagocytotic cells, such as macrophages. OUTCOMES: There was no recurrence of the lesion. LESSONS: The clinical appearance of this case resembled that of previously reported solitary cutaneous focal mucinoses. However, our case had distinctive characteristics, such as the phagocytosis of mucinous substances by myofibroblasts, multiple mucinous lesions in a single eruption, and the presence of inflammatory cells, which have not been previously reported. For this distinct cutaneous lesion, a clear dermatological and pathological name has yet to be determined. We propose "myofibroblast phagocytic cutaneous mucinosis" as a candidate name. In addition, our discoveries suggest that phagocytosis by myofibroblasts is not rare but rather is a common pathological phenomenon that has been undetected or unrecognized.

Self-healing juvenile cutaneous mucinosis, a sclerodermoid disorder simulating juvenile dermatomyositis: a case-based review.

Self-healing juvenile cutaneous mucinosis (SHJCM) is a rare childhood disease with characteristic cutaneous and rheumatic manifestations. Cutaneous manifestations include a combination of nodules affecting peri-articular (especially interphalangeal joints) and head and neck areas; and linearly arranged ivory white papules over an erythematous indurated skin. Despite a benign course, an abrupt onset of symptoms with extensive cutaneous involvement often leads to parental anxiety, overenthusiastic evaluation and sometimes aggressive treatment. A peculiar cutaneous distribution in SHJCM including nodular lesions and periorbital edema, arthritis and arthralgia in a few cases, may simulate juvenile dermatomyositis. It is, therefore, important for dermatologists and pediatricians to be aware of this entity. In this report, we describe two cases of SHJCM and briefly review similarly reported cases in children.

Nodular lichen myxoedematous: a new adverse event associated with ustekinumab.

Nodular lichen myxoedematosus is a localised form of lichen myxoedematosus, a chronic idiopathic cutaneous mucinosis of known aetiology. Ustekinumab is a human interleukin-12/23 monoclonal antibody that could directly or indirectly increase mucin production. Herein, we report for the first time a case of nodular lichen myxoedematosus associated with ustekinumab.

Cutaneous Mucinosis Associated with Beckwith-Wiedemann Syndrome.

A 37-year-old man presented with firm, skin-colored papules and nodules on his back and chest, which had been appearing during the past 7 years (Figure 1a). The patient denied any associated pruritus, pain, or ulcerations. Further history revealed he had a repaired omphalocele during childhood. Physical examination revealed a large body habitus, with asymmetric overgrowth of the right extremities when compared to the left. In addition, the patient had bilateral anterior linear earlobe creases, preauricular pits, and posterior helical pits (Figure 1b). There was no evidence of rheumatologic and endocrine disorders or paraproteinemia.

Oral focal mucinosis of the palate: a rare disease entity.

Oral focal mucinosis (OFM) is an extremely rare, benign oral soft tissue condition; less than 10 documented cases have been reported in the literature in patients under 18 years old. OFM has an unknown aetiology and predominantly presents in the fourth and fifth decades. The pathogenesis of OFM may be due to fibroblast overproduction of hyaluronic acid. Clinically, it remains almost impossible to diagnose definitively, due to its lack of pathognomonic features, therefore such lesions may have multiple differential diagnoses and histological analysis is essential to confirm OFM. We present an unusual presentation of OFM in a 14-year-old female patient. Following excision, focal myxoid degeneration of the connective tissue was apparent. This case highlights this rare condition for consideration in differential diagnosis of clinically similar lesions.

Mucinosis nodular de la mama / Nodular mucinosis of the breast

La mucinosis nodular de la mama es una rara entidad de histogénesis incierta y con comportamiento benigno. Suele presentarse como una tumoración asintomática en torno a pezón o areola y localizada en dermis o tejido celular subcutáneo. Presentamos un caso de mucinosis nodular típica. Histológicamente se define por estar constituida por lagos irregulares de mucina negativos con PAS pero positivos con hierro coloidal y azul alcián. La mucina se acompaña de estroma fibroso con un escaso componente de células fusiformes. Algunos autores sugieren un posible origen miofibroblástico. No obstante no se han realizado estudios moleculares de la mucinosis nodular. El diagnóstico diferencial se ha de hacer principalmente con lesiones mamarias benignas y malignas de estroma mucinoso. En la literatura se describen 13 casos de mucinosis nodular

Nodular mucinosis of the breast is a rare entity of uncertain histogenesis and with benign behavior. It usually presents as an asymptomatic tumor around the nipple or areola and located in the dermis or subcutaneous cellular tissue. We present a case of typical nodular mucinosis. Histologically it is defined as being composed of irregular lakes of mucin negative with PAS but positive with colloidal iron and alcian blue. Mucin is accompanied by fibrous stroma with a scarce component of fusiform cells. Some authors suggest a possible myofibroblastic origin. However, molecular studies of nodular mucinosis have not been performed. The differential diagnosis must be made mainly with benign and malignant mammary lesions of mucinous stroma. In the literature, 13 cases of nodular mucinosis are described

[Nodular mucinosis of the breast]. / Mucinosis nodular de la mama.

Nodular mucinosis of the breast is a rare entity of uncertain histogenesis and with benign behavior. It usually presents as an asymptomatic tumor around the nipple or areola and located in the dermis or subcutaneous cellular tissue. We present a case of typical nodular mucinosis. Histologically it is defined as being composed of irregular lakes of mucin negative with PAS but positive with colloidal iron and alcian blue. Mucin is accompanied by fibrous stroma with a scarce component of fusiform cells. Some authors suggest a possible myofibroblastic origin. However, molecular studies of nodular mucinosis have not been performed. The differential diagnosis must be made mainly with benign and malignant mammary lesions of mucinous stroma. In the literature, 13 cases of nodular mucinosis are described.

A Case of Papulonodular Mucinosis in a Patient With Systemic Lupus Erythematosus.

Papulonodular mucinosis is a distinctive lupus erythematosus cutaneous variant that generally occurs in patients with systemic lupus erythematosus. Despite a higher incidence of SLE in women, lupus cutaneous mucinosis occurs more frequently in men. Typically, papulonodular mucinosis appears as asymptomatic, flesh-colored papules and nodules with a propensity for the trunk and upper extremities. Herein, we report a case of papulonodular mucinosis associated with systemic lupus erythematosus in a middle-aged woman. On presentation, patient had multiple flesh-colored papules coalescing into plaques on the trunk and upper extremities. Histological findings of the lesions demonstrated a pale dermis secondary to profuse mucin deposition. Immunofluorescent staining revealed a 'lupus band' with granular deposition of immunoglobulins/complement proteins at the dermal-epidermal junction.