Grover disease (transient acantholytic dermatosis)

ERK hyperactivation in epidermal keratinocytes impairs intercellular adhesion and drives Grover disease pathology

Grover disease is an acquired dermatologic disorder characterized by pruritic vesicular and eroded skin lesions. While its pathologic features are well-defined, including impaired cohesion of epidermal keratinocytes, the etiology of Grover disease remains unclear and it lacks any FDA-approved therapy. Interestingly, drug-induced Grover disease occurs in patients treated with B-RAF inhibitors that can paradoxically activate C-RAF and the downstream kinase MEK. We recently identified hyperactivation of MEK and ERK as key drivers of Darier disease, which is histologically identical to Grover disease, supporting our hypothesis that they share a pathogenic mechanism. To model drug-induced Grover disease, we treated human keratinocytes with clinically utilized B-RAF inhibitors dabrafenib or vemurafenib and leveraged a fluorescent biosensor to confirm they activated ERK, which disrupted intercellular junctions and compromised keratinocyte sheet integrity. Consistent with clinical data showing concomitant MEK blockade prevents Grover disease in patients receiving B-RAF inhibitors, we found that MEK inhibition suppressed excess ERK activity to rescue cohesion of B-RAF-inhibited keratinocytes. Validating these results, we demonstrated ERK hyperactivation in skin biopsies of vemurafenib-induced Grover disease, but also in spontaneous Grover disease. In sum, our data define a pathogenic role for ERK hyperactivation in Grover disease and support MEK inhibition as a therapeutic strategy.

GRAPHICAL ABSTRACT

Galli-Galli Disease: A Comprehensive Literature Review

Galli-Galli disease (GGD) is a rare genodermatosis that exhibits autosomal dominant inheritance with variable penetrance. GGD typically manifests with erythematous macules, papules, and reticulate hyperpigmentation in flexural areas. A distinct atypical variant exists, which features brown macules predominantly on the trunk, lower limbs, and extremities, with a notable absence of the hallmark reticulated hyperpigmentation in flexural areas. This review includes a detailed literature search and examines cases since GGD's first description in 1982. It aims to synthesize the current knowledge on GGD, covering its etiology, clinical presentation, histopathology, diagnosis, and treatment. A significant aspect of this review is the exploration of the genetic, histopathological, and clinical parallels between GGD and Dowling-Degos disease (DDD), which is another rare autosomal dominant genodermatosis, particularly focusing on their shared mutations in the KRT5 and POGLUT1 genes. This supports the hypothesis that GGD and DDD may be different phenotypic expressions of the same pathological condition, although they have traditionally been recognized as separate entities, with suprabasal acantholysis being a distinctive feature of GGD. Lastly, this review discusses the existing treatment approaches, underscoring the absence of established guidelines and the limited effectiveness of various treatments.

Retinoids for the Treatment of Refractory Grover's Disease: A Case Series and Review of the Literature

Grover's disease, also known as transient acantholytic dermatosis (TAD), currently has no published randomized control trials regarding the treatment of the disease; thus, evidence for treatment is largely derived from case studies and case reports. In this case series, we summarize the current treatment options for Grover's disease and discuss two cases of refractory Grover's disease treated with low-dose oral isotretinoin in patients who previously failed to reach clearance with multiple treatment options. Our aim is to highlight the efficacy of low-dose systemic retinoid therapy in Grover's disease when other treatment options prove unsatisfactory.

Diagnosis and Management of Common Inflammatory Skin Diseases in Older Adults

Inflammatory skin conditions affect people of all ages, genders, and races. These common conditions are frequent causes of visits to the dermatologist. The geriatric population is often afflicted by these conditions because many are chronic and relapsing diseases. These inflammatory conditions include but are not limited to psoriasis, atopic dermatitis, contact dermatitis, seborrheic dermatitis, rosacea, and Grover disease. Chronic inflammatory skin conditions place a large burden on the health care system in the United States and have many associated comorbidities. This article discusses these inflammatory dermatoses that affect the geriatric population and common therapeutic options.

Acantholytic Dyskeratosis Consistent With Grover's Disease After Letrozole Therapy

We present a rare case of Grover's disease (GD) associated with letrozole therapy in a 66-year-old female with stage IV breast cancer. GD is a dermatological condition characterized by papulovesicular lesions typically found on the chest and trunk. While GD is linked to chemotherapeutic agents, its association with letrozole is not well documented. The patient presented with a pruritic rash on her neck, right arm, and trunk, initially misdiagnosed as contact dermatitis. Despite treatment with triamcinolone acetonide, the rash persisted. A subsequent punch biopsy confirmed acantholytic dyskeratosis consistent with GD. Discontinuation of letrozole and treatment with augmented betamethasone dipropionate resulted in significant improvement within four weeks. This case underscores the importance of considering drug-induced dermatological conditions in patients undergoing chemotherapy. While hypersensitivity drug eruptions typically present as morbilliform-patterned cutaneous eruptions, GD should be considered, especially in older patients with multiple medications. The incidence of GD following letrozole therapy is not well studied, making this case a valuable addition to the limited literature. In summary, recognizing and managing drug-induced skin conditions in cancer patients are crucial. This report contributes to our understanding of the potential association between letrozole and GD, emphasizing the need for further research in this area.

Management and Treatment of Grover’s Disease: A Case Report and Review of Literature

This case report details a rare case of Grover's disease in an 80-year-old Caucasian male complaining of a rash across his chest over the last three to four months. The patient has a past medical history of essential hypertension, hyperlipidemia, osteoarthritis of the knee, chronic gastroesophageal reflux disease (GERD), supraventricular tachycardia, status post prostate cancer, and restless legs syndrome. During his initial evaluation, he was found to have a pruritic, erythematous, papular rash most notably along his upper trunk and chest. The patient utilized multiple lotions, emollients, and anti-itch creams with minimal relief of his symptoms and presentation. Following a referral to Dermatology, a biopsy of the rash was conducted, which revealed intraepidermal acantholysis, the hallmark finding for a diagnosis of Grover's disease. Subsequently, he was treated with a topical triamcinolone acetonide 0.1% cream for 14 days. This study details a case of Grover's disease along with potential comorbidities and contributing factors in order to further understand the pathogenesis and etiology of this relatively rare condition. 

Developing a standardized approach for assessing mast cells and eosinophils on tissue biopsies: A Work Group Report of the AAAAI Allergic Skin Diseases Committee

Mast cells and eosinophils are commonly found, expectedly or unexpectedly, in human tissue biopsies. Although the clinical significance of their presence, absence, quantity, and quality continues to be investigated in homeostasis and disease, there are currently gaps in knowledge related to what constitutes quantitatively relevant increases in mast cell and eosinophil number in tissue specimens for several clinical conditions. Diagnostically relevant thresholds of mast cell and eosinophil numbers have been proposed and generally accepted by the medical community for a few conditions, such as systemic mastocytosis and eosinophilic esophagitis. However, for other mast cell- and eosinophil-associated disorders, broad discrepancies remain regarding diagnostic thresholds and how samples are processed, routinely and/or specially stained, and interpreted and/or reported by pathologists. These discrepancies can obfuscate or delay a patient's correct diagnosis. Therefore, a work group was assembled to review the literature and develop a standardized consensus for assessing the presence of mast cells and eosinophils for a spectrum of clinical conditions, including systemic mastocytosis and cutaneous mastocytosis, mast cell activation syndrome, eosinophilic esophagitis, eosinophilic gastritis/enteritis, and hypereosinophilia/hypereosinophilic syndrome. The intent of this work group is to build a consensus among pathology, allergy, dermatology, hematology/oncology, and gastroenterology stakeholders for qualitatively and quantitatively assessing mast cells and eosinophils in skin, gastrointestinal, and bone marrow pathologic specimens for the benefit of clinical practice and patients.

Drug-induced Grover's disease: a case report and review of the literature

BACKGROUND

Grover's disease (GD) is a relatively rare transient dermatosis that can be idiopathic or acquired. Acquired GD may occur secondary to internal triggers such as medications and malignancies and external factors such as friction.

OBJECTIVE

The purpose of this report is to describe the clinical and histological presentation of drug-induced Grover's disease (DIGD) and discuss potential pathogenic mechanisms.

METHODS

A systemic review of the literature was performed to identify medications implicated in DIGD.

RESULTS

We identified 13 reports of patients with DIGD. Most patients presented with a papular or papulovesicular morphology involving the trunk and extremities. Pruritus was the most common symptom. The majority of the offending agents were cancer therapeutics. Discontinuation of the culprit medication was sufficient for rash clearance and symptom resolution in most cases.

CONCLUSION

The overlap in morphology and associated symptoms in DIGD and GD makes the diagnosis of DIGD challenging and has potentially led to underdiagnosis. However, in cases of more extensive involvement and treatment recalcitrance, a drug-induced eruption should be considered.

Case for diagnosis. Atypical Grover's disease

A 55-year-old male presented with an eight-month history of erythematous papules and plaques with demarcated areas of spared skin on his trunk, upper extremities, neck, and face. Grover’s disease is a rare, acquired disorder of unknown origin, which is classically characterized by the appearance of erythematous papules on the upper trunk that are usually transient. As in the present case, there are reports of atypical disease, with facial involvement, pityriasis rubra pilaris-like lesions, and a more chronic course.

Clinical features and treatments of transient acantholytic dermatosis (Grover's disease): a systematic review

Grover's disease (GD) is an itchy acantholytic disorder occurring on the trunk of middle-aged men. Based on the best evidence, this study aimed to provide a summary of the clinical characteristics, disease course and treatments of GD. A systematic review was performed according to PRISMA guidelines for original articles published between 01.01.1970-08.15.2019, assessing clinical features and/or any type of intervention for GD. A total of 263 articles were retrieved, and 116 original reports that were deemed relevant and satisfied the inclusion criteria were included in the analysis (88 case reports, 26 case series and two retrospective reviews). From these articles, 317 patients were identified, with a male-to-female ratio of 3.95. The mean age was 59 years (range 11-92). Typical lesions were itchy papules and vesicle-papules, generally located on the trunk. Spontaneous resolution within one week to eight months was described in 42 % of cases. Topical corticosteroids (TCSs) were the most frequent treatment (response rate of 70 %) followed by systemic retinoids and corticosteroids with response rates of 86 % and 64 %, respectively. According to the results of this review, TCS appears to be the most frequently employed treatment, and we suggest TCS as first-line therapy. Second-line treatments could include systemic retinoids or systemic corticosteroids.

Cutaneous Eruptions in Patients Receiving Immune Checkpoint Blockade: Clinicopathologic Analysis of the Nonlichenoid Histologic Pattern

Cutaneous eruptions are among the most common immune-related adverse events (irAEs) associated with anti-programmed cell death protein 1/programmed cell death ligand 1 therapy, and are often clinically and histologically characterized as lichenoid. Nonlichenoid patterns may also occur and are likely to be encountered by surgical pathologists, given the increasing clinical use of these agents. The purpose of this study is to describe the histopathologic features of nonlichenoid cutaneous irAEs from patients receiving anti-programmed cell death protein 1/programmed cell death ligand 1 therapies for a variety of underlying advanced malignancies. Sixteen patients with 17 biopsied eruptions were included from 2 academic institutions with extensive experience administering and monitoring responses to immune checkpoint blockade as well as treating the potential side effects. Eruptions occurred a median of 10 days (range, 1 d to 11.4 mo) after treatment initiation. Nearly half of specimens demonstrated either a psoriasiform/spongiotic or an urticarial-type reaction pattern on histologic review. Patterns consistent with Grover disease, bullous pemphigoid, and granulomatous dermatitis were also observed. Nearly two-thirds of patients required systemic corticosteroids for treatment of the cutaneous irAE, and 19% of patients discontinued immunotherapy due to their skin eruptions. 75% of patients showed an objective antitumor response. The diverse array of nonlichenoid cutaneous irAE presented here should reflect and inform the scope of histologic patterns encountered by the practicing surgical pathologist. Such eruptions are seen in patients with a variety of underlying tumor types, many of whom ultimately demonstrate a favorable response to immune checkpoint blockade.

Bullous, pseudobullous, & pustular dermatoses

Several dermatoses are typified by the formation of spaces (blisters; bullae) within or beneath the epidermis. These may be acellular or filled with particular species of inflammatory cells. Etiological categories include infectious, immune-mediated, genetic, drug-related, and idiopathic lesions. Examples of such disorders include impetigo, Herpes virus infections, pemphigus, bullous pemphigoid and pemphigoid gestationis, epidermolysis bullosa acquisita, IgA-related dermatoses, inherited epidermolysis bullosa variants, Hailey-Hailey disease, and porphyria cutanea tarda. Other conditions manifest microscopic acantholysis within the surface epithelium but are not associated with clinical bullae, such as Darier disease and Grover disease. Finally, both infectious and non-infectious causes exist for the development of neutrophilic pustules in the epidermis, as seen in pustular psoriasis, Sneddon-Wilkinson disease (subcorneal pustular dermatosis), and acute generalized exanthematous pustulosis. This review considers the clinical and histological features of all of these diseases.

Grover's-like drug eruption in a patient with metastatic melanoma under ipilimumab therapy

Background

Dermatologic toxicity is an important adverse effect of immune checkpoint inhibitors targeting cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed cell death 1 receptor (PD-1) or PD ligand 1 (PD-L1). Skin toxicity most commonly includes a maculopapular erythematous rash and pruritus. Rarely life threatening complications such as Steven’s Johnson syndrome or toxic epidermal necrolysis may occur.

Case presentation

Here we report the uncommon event of a drug-induced transient acantholytic dermatosis (Grover’s disease) in a 73-year-old Caucasian male treated with ipilimumab for metastatic melanoma. Five weeks after initiation of therapy, the patient developed a widespread polymorphic papulovesicular dermatosis on the trunk and proximal extremities with intense pruritus. Skin biopsy showed acantholytic dyskeratosis with interface dermatitis consistent with a Grover’s-like drug eruption.

Conclusions

These findings should raise awareness for uncommon immune-related dermatological toxicities of immunomodulatory antibodies targeting the CTLA-4 signaling axis. We recommend biopsies of unexpected skin lesions to rapidly identify dermatological adverse events of immune checkpoint inhibitors.

Papular acantholytic dyskeratosis of the anogenital and genitocrural area: case series and review of the literature

BACKGROUND

Papular acantholytic dyskeratosis (PAD) of the anogenital/genitocrural area is described as a rare distinct clinicopathological entity known to dermatopathologists, although its characteristic histopathologic pattern resembles both Hailey-Hailey disease and Darier disease. The objective of this study is to describe the clinical characteristics, histopathologic features and response to treatment of PAD.

METHODS

We report in detail six cases of PAD. A literature search of the keyword 'papular acantholytic dyskeratosis' was performed on Google scholar and PubMed, 21 cases of this entity were found. A total of 27 patients including our six cases are reviewed in this study.

RESULTS

The mean age at diagnosis was 38.8 years with a male to female ratio of 0.8 : 1. Clinically, papular lesions (55.6%) are the typical manifestation of PAD, and the anogenital area (63%) is the most commonly involved site. Lesions were resistant to topical steroids, subcutaneous interferon and antibiotics while one case showed complete resolution of the lesions after retinoid therapy. Laser therapy showed good results in one case. None of the patients had spontaneous remission.

CONCLUSION

Awareness of the clinicopathological hallmarks herein may be important to avoid underdiagnosis of PAD and may contribute to understanding the pathogenesis of this rare disease.

Epidermal multinucleated giant cells are not always a histopathologic clue to a herpes virus infection: multinucleated epithelial giant cells in the epidermis of lesional skin biopsies from patients with acantholytic dermatoses can histologically mimic a herpes virus infection

BACKGROUND

Multinucleated giant cells in the epidermis can either be epithelial or histiocytic. Epithelial multinucleated giant cells are most often associated with herpes virus infections.

PURPOSE

To review the histologic differential diagnosis of conditions with epithelial and histiocytic multinucleated giant cells-since multinucleated giant cells in the epidermis are not always pathognomonic of a cutaneous herpes virus infection-and to summarize dermatoses in which herpes virus infection has been observed to coexist.

METHODS

Two individuals with acantholytic dermatoses whose initial lesional skin biopsies showed multinucleated epithelial giant cells suggestive of a herpes virus infection are reported. Using the PubMed database, an extensive literature search was performed on multinucleated giant cell (and epidermis, epithelial, and histiocytic) and herpes virus infection. Relevant papers were reviewed to discover the skin conditions with either multinucleated giant cells in the epidermis or coincident cutaneous herpes virus infection.

RESULTS

Initial skin biopsies from patients with either pemphigus vulgaris or transient acantholytic dermatosis mimicked herpes virus infection; however, laboratory studies and repeat biopsies established the correct diagnosis of their acantholytic dermatosis. Hence, epidermal multinucleated giant cells are not always a histopathologic clue to a herpes virus infection. Indeed, epithelial multinucleated giant cells in the epidermis can be observed not only in the presence of infection (herpes virus), but also acantholytic dermatoses and tumors (trichoepithelioma and pleomorphic basal cell carcinoma). Histiocytic multinucleated giant cells in the epidermis can be observed in patients with either giant cell lichenoid dermatitis or lichen nitidus of the palms.

CONCLUSIONS

Epithelial and histiocytic multinucleated giant cell can occur in the epidermis. Keratinocyte-derived multinucleated giant cells are most commonly associated with herpes virus infection; yet, they can also be observed in patients with skin tumors or acantholytic dermatoses. Cutaneous herpes simplex virus infection can coexist in association with other conditions such as acantholytic dermatoses, benign skin tumors, bullous disorders, hematologic malignancies, inflammatory dermatoses, and physical therapies. However, when a herpes virus infection is suspected based upon the discovery of epithelial multinucleated giant cells in the epidermis, but either the clinic presentation or lack of response to viral therapy or absence of confirmatory laboratory studies does not support the diagnosis of a viral infection, the possibility of a primary acantholytic dermatosis should be considered and additional lesional skin biopsies performed. Also, because hematoxylin and eosin staining is not the golden standard for confirmation of autoimmune bullous dermatoses, skin biopsies for direct immunofluorescence should be performed when a primary bullous dermatosis is suspected since the histopathology observed on hematoxylin and eosin stained sections can be misleading.

Is Grover's disease an autoimmune dermatosis?

Grover's disease (GD) is a transient or persistent, monomorphous, papulovesicular, asymptomatic or pruritic eruption classified as non-familial acantholytic disorder. Contribution of autoimmune mechanisms to GD pathogenesis remains controversial. The purpose of this study was to investigate antibody-mediated autoimmunity in 11 patients with GD, 4 of which were positive for IgA and/or IgG antikeratinocyte antibodies by indirect immunofluorescence. We used the most sensitive proteomic technique for an unbiased analysis of IgA- and IgG-autoantibody reactivities. Multiplex analysis of autoantibody responses revealed autoreactivity of all 11 GD patients with cellular proteins involved in the signal transduction events regulating cell development, activation, growth, death, adhesion and motility. Semiquantitative fluorescence analysis of cultured keratinocytes pretreated with sera from each patient demonstrated decreased intensity of staining for desmoglein 1 and/or 3 and PCNA, whereas 4 of 10 GD sera induced BAD expression, indicating that binding of autoantibodies to keratinocytes alters expression/function of their adhesion molecules and activates apoptosis. We also tested the ability of GD sera to induce visible alterations of keratinocyte shape and motility in vitro but found no specific changes. Thus, our results demonstrated that humoral autoimmunity in GD can be mediated by both IgA and IgG autoantibodies. At this point, however, it is impossible to conclude whether these autoantibodies cause or are caused by the disease. Antidesmoglein antibodies may be triggered by exposure to immune system of sequestered antigens due to disintegration of desmosomes during primary acantholysis. Clarifying aetiology of GD will help improve treatment, which currently is symptomatic and of marginal effectiveness.

Chronic pruritus: a paraneoplastic sign

Chronic itch could be a presenting sign of malignancy. Pruritus of lymphoma is the common prototype of paraneoplastic itch and can precede other clinical signs by weeks and months. Paraneoplastic pruritus has also been associated with solid tumors and is an important clinical symptom in paraneoplastic skin diseases such as erythroderma, Grovers disease, malignant acanthosis nigricans, generalized granuloma annulare, Bazex syndrome, and dermatomyositis. In any case with high index of suspicion a thorough work-up is required. This review highlights the association between itch and malignancy and presents new findings related to pathophysiological mechanisms and the treatment of itch associated with malignancy. Combinative therapies reducing itch sensitization and transmission using selective serotonin and neuroepinephrine reuptake inhibitors, Kappa opioids, and neuroleptics are of prime importance in reducing this bothersome symptom.

Leukemia cutis in association With Grover's disease

Grover's disease (GD), or transient acantholytic dermatosis, is a persistent recurrent dermatosis that usually occurs in men older than 50 years. Rare cases of GD and hematologic malignancy in the same cutaneous biopsy specimen have been reported. We report a case of GD in association with leukemia cutis. A 72-year-old man with a history of myelodysplastic syndrome presented with numerous pruritic papules on the torso, which were clinically diagnosed as GD. A skin biopsy revealed foci of suprabasal acantholysis and dyskeratosis consistent with GD and dense aggregates of mononuclear atypical cells in the superficial dermis consistent with leukemia cutis. Direct immunofluorescence was negative. This case illustrates the need to consider a diagnostic skin biopsy in any patient who presents with classic clinical findings of GD if there is any indication that the patient may be at higher risk for a hematologic malignancy.