Appearances may be deceptive: florid cutaneous and mucosal papillomatosis

We present a case in which a patient presented with widespread cutaneous warty lesions misdiagnosed as warts 3 months before the diagnosis of his advanced gastric adenocarcinoma. Florid cutaneous and mucosal papillomatosis is a paraneoplastic dermatosis, following a parallel course with the underlying malignancy, which is most often gastric adenocarcinoma.

Two Cases of Insulin-Derived Amyloidosis With Acanthosis Nigricans-Like Changes

ABSTRACT

Insulin-derived amyloidosis (AIns) is a rare iatrogenic subtype of cutaneous amyloidosis occurring at frequent insulin injection sites. Here, we describe 2 cases of AIns accompanied by acanthosis nigricans (AN)-like changes, a rare finding which has been reported fewer than 5 times in the literature. We also report the first case of an AIns nodule being misdiagnosed as a keloid. Both of our patients presented with asymptomatic, hyperkeratotic, pigmented plaques at frequent insulin injection sites, and histopathologic examination showed (1) nodular aggregates of amyloid demonstrating apple-green birefringence with Congo red staining and (2) AN-like features, such as epidermal papillomatosis, hyperkeratosis, and hyperpigmentation. Accurate diagnosis of AIns is crucial, because repeated insulin injection into a nodule can impair glycemic control. However, misdiagnosis is common, as observed with our second patient, whose AIns nodule was misdiagnosed by an outside provider as a keloid, perhaps because of the presence of AN-like features. Our case report adds to the limited but growing body of literature on AIns and significantly increases the number of reported cases of AIns with AN-like features, an even rarer phenomenon.

Cutaneous Manifestations of Diabetes

Diabetes mellitus is a significant worldwide health concern and cutaneous manifestations are common. This review describes characteristic skin findings of diabetes, general skin findings related to diabetes, and findings related to diabetes treatment with a focus on clinical presentation, diagnosis, pathophysiology, epidemiology, and treatment. As the prevalence of diabetes continues to rise, cutaneous manifestations of diabetes mellitus likely will be encountered more frequently by physicians in all disciplines including dermatologists and primary care physicians. Accordingly, knowledge regarding the prevention, diagnosis, and management of cutaneous manifestations is an important aspect in the care of patients with diabetes.

A Molecular Perspective on the Potential Benefits of Metformin for the Treatment of Inflammatory Skin Disorders

Due to its anti-hyperglycemic effect, metformin is the first-line medication for the treatment of type 2 diabetes, particularly in people who are obese. However, metformin is a drug with a very wide range of pharmacological properties and reports of its therapeutic effect on diseases including inflammation and cancer are increasing. Numerous research groups have reported that metformin has beneficial effects on a variety of inflammatory skin disorders including psoriasis, acanthosis nigricans, acne, hidradenitis suppurativa, and allergic contact dermatitis. According to these reports, in addition to the well-known action of metformin, that is, its anti-hyperglycemic effect, NF-kB inhibition and the resulting alteration to the cytokine network may be the potential targets of metformin. Its anti-hyperandrogenism effect has also been confirmed as the major action of metformin in some inflammatory skin diseases. Moreover, novel regulatory mechanisms, including autophagy and antioxidant processes, have been suggested as promising mechanisms of action for metformin in inflammatory skin disorders.

Clinical characteristics of adolescent cases with Type A insulin resistance syndrome caused by heterozygous mutations in the β-subunit of the insulin receptor (INSR) gene

BACKGROUND

Type A insulin resistance (IR) is a rare form of severe congenital IR that is frequently caused by heterozygous mutations in the insulin receptor (INSR) gene. Although Type A IR requires appropriate intervention from the early stages of diabetes, proper diagnosis of this disease is challenging, and accumulation of cases with detailed clinical profiles and genotypes is required.

METHODS

Herein we report on six peripubertal patients with clinically diagnosed Type A IR, including four patients with an identified INSR mutation. To clarify the clinical features of Type A IR due to INSR mutation, we validated the clinical characteristics of Type A IR patients with identified INSR mutations by comparing them with mutation-negative patients.

RESULTS

Four heterozygous missense mutations within the β-subunit of INSR were detected: Gly1146Arg, Arg1158Trp, Arg1201Trp, and one novel Arg1201Pro mutation. There were no obvious differences in clinical phenotypes, except for normal lipid metabolism and autosomal dominant inheritance, between Type A IR due to INSR mutations and Type A IR due to other factors. However, our analysis revealed that the extent of growth retardation during the fetal period is correlated with the severity of insulin signaling impairment.

CONCLUSIONS

The present study details the clinical features of four patients with genetically proven Type A IR. Further accumulation of genetically proven cases and long-term treatment prognoses following early diagnosis are required to further elucidate the dynamics of this disease.

A novel insulin receptor mutation in an adolescent with acanthosis nigricans and hyperandrogenism

Insulin receptor mutations cause extreme insulin resistance resulting in acanthosis nigricans and hyperandrogenism. We report a pre-menarchal adolescent female with normal weight, with severe acanthosis nigricans, acne, and hirsutism. Initial investigation revealed elevated fasting and post-prandial insulin and high testosterone and androstenedione levels. Her father had frequent complaints of hypoglycemia. Coding sequence and splice junction analysis of the INSR gene, in our patient and her father, revealed a heterozygous missense mutation in the β subunit of the insulin receptor (Arg1131Trp), resulting in receptor loss of function. Metformin therapy and carbohydrate control improved acanthosis and menarche ensued within 3 months. Our case highlights the importance of distinguishing insulin resistance commonly associated with obesity from monogenic defects. Although, there is no consensus on treatment of children with monogenic forms of insulin resistance due to its rarity, dietary and lifestyle modifications and insulin-sensitizing agents play a key role in management.

Luteolin-7-glucoside inhibits IL-22/STAT3 pathway, reducing proliferation, acanthosis, and inflammation in keratinocytes and in mouse psoriatic model

The epidermis is a dynamic tissue in which keratinocytes proliferate in the basal layer and undergo a tightly controlled differentiation while moving into the suprabasal layers. The balance between keratinocyte proliferation, differentiation, and death is essential, and its perturbation can result in pathological changes. Some common skin diseases, such as psoriasis, are characterized by hyperproliferation accompanied by inflammatory reactions, suggesting that molecules with topical anti-inflammatory and ROS scavenging abilities may be useful for their treatment. Here we investigate the potential of the flavone Luteolin-7-glucoside (LUT-7G) as a treatment for psoriasis. We show that LUT-7G leads to a modification of the cell cycle and the induction of keratinocyte differentiation, with modification of energy, fatty acid, and redox metabolism. LUT-7G treatment also neutralizes the proliferative stimulus induced by the proinflammatory cytokines IL-22 and IL-6 in HEKn. Moreover, in the Imiquimod (IMQ) mouse model of psoriasis, topical administration of LUT-7G leads to a marked reduction of acanthosis and re-expression of epidermal differentiation markers. Dissection of the IL-22 signalling pathway, activated by IMQ treatment, demonstrates that LUT-7G impairs the nuclear translocation of phosphorylated (activated) STAT3, blocking the IL-22 signalling cascade. Thus LUT-7G appears to be a promising compound for the treatment of hyperproliferative and inflammatory skin diseases, such as psoriasis.

A case of acanthosis nigricans coexisting with mycosis fungoides

Acanthosis nigricans maligna (ANM) is a paraneoplastic phenomenon most commonly associated with visceral adenocarcinoma, in particular, gastric adenocarcinoma. Clinically, AMN is characterized by rapidly progressive symmetrical skin thickening and hyperpigmentation of the intertriginous areas with peripheral acrochorda. The diagnosis is made by a detailed medical work-up for occult malignancies with particular emphasis on endocrinological diseases. We report a 67-year-old man that presented clinically with acanthosis nigricans, in which a subsequent diagnosis of mycosis fungoides was made.

Acanthosis nigricans, vitamin D, and insulin resistance in obese children and adolescents

OBJECTIVES

The aim of this study is to identify factors accounting for the variation in 25-hydroxyvitamin D levels in a pediatric obese population.

PATIENTS AND METHODS

One hundred and forty-nine obese children and adolescents (BMI ≥95th percentile) were evaluated in a pediatric endocrine office. Acanthosis nigricans (AN) skin lesions were rated on a 4-point scale.

RESULTS

The 25-hydroxyvitamin D levels were significantly different between those without AN and those with any severity of AN (p=<0.001). Insulin levels were only significantly different between those with no and severe AN (p=0.007). A general linear model showed that month of visit predicted 19.0% of the variation and AN an additional 2.2%. When AN was dropped from the full model, log-transformed HOMA-IR remained insignificant (p=0.164).

CONCLUSIONS

Season of evaluation was the main determinant of 25-hydroxyvitamin D levels. Severity of AN was a stronger predictor of 25-hydroxyvitamin D level variation than the measure of insulin resistance HOMA-IR.

[Malignant acanthosis nigricans: report of a case]

The authors present a case of a 44-year-old patient with a disseminated dermatosis diagnosed as acanthosis nigricans. The patient was a smoker and investigation of the cause of her skin lesions resulted in discovery of an asymptomatic metastatic carcinoma in the laryngopharanx, probably of pulmonary origin.

Case of exogenous insulin-derived acanthosis nigricans caused by insulin injections

A 73-year-old male with diabetes mellitus had been treated with insulin for six years. He developed a solid mass on his left lateral of the abdomen at the insulin injection site. A firm subcutaneous mass with dark-red erythema was overlaid by dark-brown keratinized plaques. On histological examination of the mass, keratin proliferation and epidermal papilloma were observed. There were four previously reported cases of acanthosis nigricans that were considered to be caused by continuous injections of insulin. Using immunohistochemistry, in our case the findings were positive in the basal epithelial and prickle cell layers when the patient's lesion was dyed with insulin-like growth factor (IGF)-1 antibody. The coexistence of dermal IGF-1 receptor and acanthosis nigricans found in our patient has not been reported previously, to our knowledge.

Acanthosis nigricans in adolescents: a practical approach

Acanthosis nigricans (AN) is a lesion affecting localized areas of the skin in persons with obesity and/or hyperinsulinemia. Biochemical mechanisms responsible for developing this hyperplastic lesion are unclear, but likely involve local cutaneous growth factors. It is associated with obesity, endocrinopathies (insulin resistance, diabetes mellitus, Cushing disease and acromegaly) and visceral malignancies. Clinicians should recognize AN because it may herald disorders ranging from endocrine disturbances to malignancy. Early recognition of these conditions is essential to identify children who are at highest risk for developing type 2 diabetes and further metabolic abnormalities.

[Acral acanthosis nigricans associated with taking growth hormone]

Acanthosis nigricans is a skin lesion characterized by the presence of a hyperpigmented, velvety cutaneous thickening that usually appears in flexural areas. Less frequently, it can occur in other locations, such as the dorsum of hands and feet. In this case it is called acral acanthosis nigricans. It is a dermatological manifestation of systemic disease. It is often associated with insulin resistance-mediated endocrine diseases. A case is presented on a patient with acanthosis nigricans secondary to the use of growth hormone.

Multiple consequences of a single amino acid pathogenic RTK mutation: the A391E mutation in FGFR3

The A391E mutation in fibroblast growth factor receptor 3 (FGFR3) is the genetic cause for Crouzon syndrome with Acanthosis Nigricans. Here we investigate the effect of this mutation on FGFR3 activation in HEK 293 T cells over a wide range of fibroblast growth factor 1 concentrations using a physical-chemical approach that deconvolutes the effects of the mutation on dimerization, ligand binding, and efficiency of phosphorylation. It is believed that the mutation increases FGFR3 dimerization, and our results verify this. However, our results also demonstrate that the increase in dimerization is not the sole effect of the mutation, as the mutation also facilitates the phosphorylation of critical tyrosines in the activation loop of FGFR3. The activation of mutant FGFR3 is substantially increased due to a combination of these two effects. The low expression of the mutant, however, attenuates its signaling and may explain the mild phenotype in Crouzon syndrome with Acanthosis Nigricans. The results presented here provide new knowledge about the physical basis behind growth disorders and highlight the fact that a single RTK mutation may affect multiple steps in RTK activation.

Exogenous insulin-derived acanthosis nigricans: could it be a cause of increased insulin requirement?

Acanthosis nigricans is a cutaneous manifestation of insulin resistance. We herein present a case of localized acanthosis nigricans over the abdomen in a 14-year-old boy with type 1 diabetes mellitus. The acanthosis nigricans appeared secondary to repeated insulin injection over same site. After advising the patient about rotating the injection site there was better disease control along with drop in insulin requirement and a significant reduction in the size of the lesion.

Case report: acanthosis nigricans resulting from repetitive same-site insulin injections

Although acanthosis nigricans (AN) may be associated with internal malignancies, a benign form is more common, and a subset of these is drug-induced. In this case, a solitary, hyperpigmented, acanthotic plaque developed on the right abdomen after daily, same-site injections of insulin over a six-month period. The lesion completely resolved eight months after insulin injections were rotated to other locations. Acanthosis nigricans recurred, however, at the original location two months after the patient resumed serial same-site insulin injections, against medical advice. This provides direct evidence that localized hyperinsulinism is causally related to AN through its effect on insulin-like growth factor receptors.

Acanthosis nigricans as a local cutaneous side effect of repeated human insulin injections

Acanthosis nigricans is a hyperkeratotic lesion of the epidermis associated with insulin resistance. We present a diabetic patient with acanthosis nigricans at the insulin injection site on the abdominal wall. Neglecting rotation of sites for insulin injections and local hyperinsulinemia may play a role in the development of acanthosis nigricans.

Verruca vulgaris in a plaque of acanthosis nigricans

Warts are common cutaneous tumors, induced by different strains of the human papilloma virus. Many people develop one or more warts in their lifetime, most of which resolve spontaneously. We present a case of multiple warts within a plaque of acanthosis nigricans probably related to autoinoculation.

Acanthosis nigricans and truncal fat in overweight and obese children

BACKGROUND

Screening for acanthosis nigricans (AcN) in overweight children is repeatedly recommended. The significance of AcN, and its relation to central obesity in children, is unclear.

OBJECTIVE

To compare clinical and anthropometric parameters associated with adiposity, between overweight and obese children with and without AcN.

METHODS

One hundred and forty-nine overweight and obese children were screened for AcN. Height, weight, waist and hip circumferences, triceps skinfold thickness and segmental body fat amounts were measured.

RESULTS

Twenty-two (14.8%) children had AcN. Children with AcN had greater height, weight, BMI, waist circumference, waist-to-height-ratio, triceps skinfold thickness, and total and truncal body fat percentage, compared to those without AcN. After adjustment for age and BMI, no adiposity measure was increased in children with AcN.

CONCLUSION

Overweight and obese children with AcN basically have greater overall and central adiposity, than those without it. Adjusting for BMI, there is no evidence for increased abdominal fat in these children.

Palliative treatment of paraneoplastic acanthosis nigricans and oral florid papillomatosis with retinoids

Malignant acanthosis nigricans (MAN) with oral florid papillomatosis is a rare paraneoplastic condition affecting the skin and mucocutaneous tissues associated with an underlying malignancy. It is characterized by proliferation of keratinocytes resulting in papillomatous change and hyperpigmentation of the skin and multiple confluent warty or verrucous lesions of the oral mucous membranes. The oral involvement can interfere with the patient's ability to eat and drink. There is no specific therapy for this complication. Treatment of the underlying malignancy can lead to improvement of symptoms, but the degree of improvement varies. Here, the authors present a case of MAN with oral florid papillomatosis associated with gastric adenocarcinoma that was treated with oral retinoids resulting in significant clinical improvement of the hyperkeratosis and hyperpigmentation as well as improved patient functionality.

Paraneoplastic Acanthosis Nigricans: The importance of exhaustive and repeated malignancy screening

Paraneoplastic acanthosis nigricans (P-AN) characteristically has a sudden onset, rapid progression, and extensive cutaneous involvement. The association between P-AN and internal malignancy is well established and the most common association is with adenocarcinoma of gastrointestinal origin. We present the case of an 81-year-old man with a 12-month history of anorexia, weight loss, and clinical evidence of extensive acanthosis nigricans. After exhaustive and repeated investigations a papillary thyroid carcinoma and a follicular adenoma were identified and he improved upon its resection. To our knowledge, P-AN in association with thyroid neoplasm has been reported on only one previous occasion.

Extensive segmental acanthosis nigricans form of epidermal nevus

Eight cases of the acanthosis nigricans form of epidermal nevus have been described in literature. The present case is impressive and has an extensive segmental distribution. Although etiological factors, such as mutations in the FGFR3 gene, are becoming recognized, treatment options remain limited. We present a case of a 14-year-old male with multiple hyperpigmented, hyperkeratotic plaques on the upper body, axillae, and groin with a segmental distribution following Blaschko lines. Histopathological investigation showed aspects of both acanthosis nigricans and epidermal nevus. So far, screening has not revealed any internal abnormalities. As previous cases show a clear association with internal diseases, repetitive screening for internal diseases and syndromes is suggested in the case of the acanthosis nigricans form of epidermal nevus. Treatment of the condition remains a challenge.

Mediastinal lymph node metastasis of lung cancer with an unknown primary lesion having concurrent endocrine abnormality and acanthosis nigricans: report of a case

We herein describe a patient we encountered in whom mediastinal lymph node metastasis of lung cancer with an unknown primary lesion was complicated by both an endocrine abnormality and acanthosis nigricans. A 66-year-old male visited a local hospital and was diagnosed as having acanthosis nigricans. The patient was referred to our hospital for further examination. Computed tomography scans of the chest and the abdomen showed no adverse findings except for an enlargement of the mediastinal lymph node. No malignant lesions were detected in examinations of the upper gastrointestinal tract. Based on the above findings, the lesion was thus considered to possibly be mediastinal lymph node metastasis of an unknown primary tumor or malignant lymphoma. A thoracoscopic biopsy of the mediastinal lymph node was performed. The patient was diagnosed to have mediastinal lymph node metastasis of lung cancer with an unknown primary lesion and endocrine abnormality resulting from paraneoplastic syndrome. Palliative radiation therapy was initiated to prevent superior vena cava syndrome and esophageal passage failure or dysphagia. The cutaneous lesions markedly improved thereafter. The serum levels of adrenocorticotropic hormone decreased.

[Case of a Japanese female presenting severe achondroplasia with developmental delay and acanthosis nigricans (SADDAN) syndrome with a K650M mutation in the fibroblast growth factor receptor 3 gene]

We diagnosed a Japanese female as having severe achondroplasia with developmental delay and acanthosis nigricans (SADDAN) syndrome. Genetic analysis revealed a K650M point mutation in the fibroblast growth factor receptor 3 (FGFR3) gene, described in only six other individuals in the world. The medical history of the present case includes severe skeletal dysplasia at birth, progressive acanthosis nigricans in infancy, and severe central nervous system structural abnormalities, consisting of the absence of right cerebral hemisphere (hydranencephaly), ventricular dilatation, both indicating congenital brain malformation, and porencephaly indicating destructive brain damages. The patient is severely retarded and has suffered from intractable seizures. This is the first report of a Japanese patient and the seventh case of SADDAN syndrome confirmed genetically.

[Oral and perioral endogenous pigmented lesions]

Pigmented lesions are commonly found in the mouth. Such lesions represent a variety of clinical entities, ranging from physiologic changes to manifestations of systemic illnesses and malignant neoplasms. Two groups of pigmented lesions of the oral mucosa are recognized: 1) endogenous lesions, including racial pigmentations, melanotic macules, melanocytic nevi, malignant melanoma and 2) exogenous lesions (e.g., blood-related pigmentations, metallic pigmentations). The etiology, differential diagnosis, clinical and histopathological features and management of endogenous pigmented lesions is discussed and the current literature is reviewed. In this article, pigmented lesions are described to allow practitioner to elaborate a positive diagnosis of endogenous pigmented lesions and to facilitate an early detection of these lesions particularly the malignant ones.

Acanthosis nigricans: a practical approach to evaluation and management

Acanthosis nigricans is a dermatosis characterized by thickened, hyperpigmented plaques, typically of the intertriginous surfaces and neck. Common in some populations, its prevalence depends on race. Clinicians should recognize acanthosis nigricans; it heralds disorders ranging from endocrinologic disturbances to malignancy. In this review, we discuss the pathogenesis of acanthosis nigricans and its clinical implications and management.

Oral acanthosis nigricans: case report and comparison with literature reports

Acanthosis nigricans (AN) is a rare condition which may affect oral cavity. There are two forms of AN: benign and malignant. Benign AN may be hereditary, or may be related to systemic diseases or drugs. Malignant AN is most often associated with gastric adenocarcinoma but cancers of other sites and types may also occur. This case report is based on a case of a 78-year-old woman suffering from invasive bladder papillary transitional cell carcinoma accompanied by extensive papillomatous areas of normal mucosal color and soft consistency involving the lips, buccal mucosa and hard palate. Verrucous changes with tiny pigmented macules were also found on the skin of the right ear auricle. Oral lesions occurred after the tumor had been diagnosed, i.e. after third operation for tumor recurrence. The fifth operation for tumor recurrence resulted in slight improvement of oral changes. It is concluded that the severity of oral changes is in correlation with tumor progression. The occurrence of oral lesions may be an indicator of tumor progression.

Is Acanthosis Nigricans a reliable indicator for risk of type 2 diabetes?

Acanthosis nigricans (AN) is a thickening and hyperpigmentation of the skin commonly found on the neck, axilla, or groin and is generally caused by hyperinsulinemia, a consequence of insulin resistance associated with obesity. Insulin resistance is a primary risk factor for the development of type 2 diabetes, hypercholesterolemia, and hypertension. Screening for acanthosis nigricans is controversial and not recommended by the Centers for Disease Control and Prevention; however, some states, such as Texas, are implementing AN screenings in schools to identify those children who are at highest risk for developing type 2 diabetes. With the current epidemics of obesity and diabetes, school nurses will see students in the health office with AN and should be knowledgeable about this skin condition and the association with hyperinsulinemia and obesity. The school nurse's role is to educate and assist students and their families in seeking appropriate medical advice based on current knowledge of risk factors. This article will explore the controversy associated with screening for AN and make recommendations for school nursing practice.

Familial acanthosis nigricans due to K650T FGFR3 mutation

BACKGROUND

Acanthosis nigricans is a feature of several syndromes caused by activating mutations of the fibroblast growth factor receptor 3 gene (FGFR3), including Crouzon syndrome with acanthosis nigricans, thanatophoric dysplasia, and severe achondroplasia with developmental delay and acanthosis nigricans (SADDAN syndrome).

OBSERVATIONS

We describe a healthy 4-year-old African American girl with generalized acanthosis nigricans since infancy. Her father had a history of acanthosis nigricans since childhood, in addition to Crohn disease, obesity, and adult-onset diabetes mellitus. A pedigree with numerous affected family members was constructed. Other than slightly short stature, no associated anomalies were found, including dysmorphic features or skeletal or neurologic defects. Genetic testing revealed a previously undescribed, heterozygous lysine to threonine mutation at codon 650 of the FGFR3 gene in the 4 affected family members who were tested.

CONCLUSION

Extensive acanthosis nigricans in early childhood, especially with a family history of acanthosis nigricans, may warrant testing for FGFR3 mutations.

The effects of IL-20 subfamily cytokines on reconstituted human epidermis suggest potential roles in cutaneous innate defense and pathogenic adaptive immunity in psoriasis

IL-19, IL-20, IL-22, IL-24, and IL-26 are members of the IL-10 family of cytokines that have been shown to be up-regulated in psoriatic skin. Contrary to IL-10, these cytokines signal using receptor complex R1 subunits that are preferentially expressed on cells of epithelial origin; thus, we henceforth refer to them as the IL-20 subfamily cytokines. In this study, we show that primary human keratinocytes (KCs) express receptors for these cytokines and that IL-19, IL-20, IL-22, and IL-24 induce acanthosis in reconstituted human epidermis (RHE) in a dose-dependent manner. These cytokines also induce expression of the psoriasis-associated protein S100A7 and keratin 16 in RHE and cause persistent activation of Stat3 with nuclear localization. IL-22 had the most pronounced effects on KC proliferation and on the differentiation of KCs in RHE, inducing a decrease in the granular cell layer (hypogranulosis). Furthermore, gene expression analysis performed on cultured RHE treated with these cytokines showed that IL-19, IL-20, IL-22, and IL-24 regulate many of these same genes to variable degrees, inducing a gene expression profile consistent with inflammatory responses, wound healing re-epithelialization, and altered differentiation. Many of these genes have also been found to be up-regulated in psoriatic skin, including several chemokines, beta-defensins, S100 family proteins, and kallikreins. These results confirm that IL-20 subfamily cytokines are important regulators of epidermal KC biology with potentially pivotal roles in the immunopathology of psoriasis.