Clinical Mimickers Research Articles

Histopathological study of scaly plaque over palm and sole in patients attending a tertiary care Hospital in Kathmandu

Background: Dermatoses of palms and soles are frequently encountered as palms and soles have non-hairy skin. Scaling skin could be a symptom of many medical conditions including psoriasis, eczema, contact dermatitis, ichthyosis, actinic keratosis, lichen planus, tinea, etc. Psoriasis must be differentiated from its non-psoriatic lesions. Histopathological examination often serves as a confirmative part of the diagnosis. Materials and methods: This was a hospital-based retrospective study carried out in the Department of Pathology and Department of Dermatology of Nepal Medical College Teaching Hospital. A total of 139 cases of scaly plaque skin lesions of the palm and sole from January 2020 to December 2022 were included in the study. The histopathological diagnosis was correlated with the clinical diagnosis. Results: Among 139 persons presenting with scaly lesions, the median age was 36 years with an age range from 15 years to 80 years. A female preponderance (59%) was observed. The odds of Psoriasis were 2.5 times higher (OR CI: 1.21 to 5.17) among those aged 36 years and above (P value 0.011). There was a significant association between age categories and histological diagnosis of scaly lesions. The agreement was significant between the clinical and histological diagnosis for psoriatic (63.0%) and non-psoriatic lesions (76.3%) with a Cohen’s kappa coefficient of 0.38 (SE: 0.084), P value < 0.0001. Conclusions: Both psoriatic and non-psoriatic lesions can present as scaly plaque skin lesions, hence the knowledge of these clinical mimickers is important for the proper diagnosis. The histopathological examination will give the confirmatory diagnosis.

Clinical and Dermoscopic Patterns of Basal Cell Carcinoma and Its Mimickers in Skin of Color: A Practical Summary.

The diagnosis of basal cell carcinoma (BCC) in dark phototypes can be a challenging task due to the lack of relevant clues and its variable presentation. In this regard, there is growing evidence that dermoscopy may benefit the recognition of BCC even for skin of color (SoC). The objective of this review is to provide an up-to-date overview on clinical and dermoscopic patterns of BCC in SoC, also comparing such findings with those of the main clinical mimickers reported in the literature. A comprehensive search of the literature through the PubMed electronic database was carried out in order to identify papers describing the clinical and dermoscopic features of BCC in dark phototypes (IV-VI). By finding macroscopic clinical presentations of BCCs in SoC patients and any possible clinical mimickers considered in the retrieved papers, we built a differential diagnosis list and analyzed the dermoscopic findings of such conditions to facilitate the diagnosis of BCC. BCC in darker skin may present as pigmented nodular lesions, pigmented patches or plaques, ulcers, erythematous nodular lesions, erythematous plaques or patches, or scar-like lesions, depending on its subtype and body site. The differential diagnosis for BCC in patients with SoC includes squamous cell carcinoma, melanoma, nevi, adnexal tumors and sebaceous keratosis. Additionally, it differs from that of Caucasians, as it also includes lesions less common in fair skin, such as dermatosis papulosa nigra, melanotrichoblastoma, and pigmented dermatofibrosarcoma protuberans, and excludes conditions like actinic keratosis and keratoacanthoma, which rarely appear in darker skin. The resulting differences also include infectious diseases such as deep cutaneous mycosis and inflammatory dermatoses. The most prevalent differentiating dermoscopic feature for BCC includes blue, black and gray dots, though arborizing vessels still remain the predominant BCC feature, even in dark phototypes. Diagnostic approach to BCC in dark-skinned patients varies due to the prevalence of dermoscopy findings associated with hyperpigmented structures. Clinicians should be aware of such points of differentiation for a proper management of this tumor in SoC.

Dermoscopy of pigmented basal cell carcinoma: a descriptive study in Indian population

Background: Pigmented basal cell carcinoma (BCC) is more common in brown-skinned than white-skinned individuals. Histopathology is the gold standard for the diagnosis. There is a paucity of published literature on dermoscopy of BCC in brown skin, particularly in the Indian population. Aims: To study the dermoscopic features of pigmented BCC in brown skin. Methods: This was a cross-sectional, hospital-based study in which dermoscopy was performed on 20 patients with pigmented BCC. Results: Out of 20 patients studied, 12 patients had noduloulcerative BCC, 3 patients had nodular BCC, 4 patients had superficial spreading BCC, and 1 patient had morpheaform BCC. Blue-grey globules, ulceration, and arborizing vessels were noted predominantly in nodular BCC. In contrast, whereas maple-leaf-like areas, spoke wheel structures, erosions, and short-fine telangiectasia were seen in superficially spreading BCC. Morpheaform BCC showed the characteristic stellate pattern of vessels, homogenous white areas, and signature pattern observed in a patient with multiple BCCs. Conclusion: Dermoscopy, a non-invasive investigation, cannot replace the gold standard histopathology but can provide valuable information for its diagnosis, identifying the subtype and presence of pigment, differentiating from its clinical mimickers, and helping in its management.

Hidradenitis Suppurativa-Induced Breast Abscess and Congenital Nipple Inversion Mimicking Inflammatory Breast Cancer with Review of the Literature

Inflammatory breast cancer (IBC) is an aggressive, but rare, malignancy that may present cutaneously, so dermatologists may be some of the first providers to observe the initial clinical signs. A number of benign conditions may mimic the cutaneous and radiographic features of IBC. We present a case of a patient with hidradenitis suppurativa of the breast complicated by abscess formation with cutaneous findings mimicking IBC, including abrupt erythema, edema, nipple retraction, and peau d’orange changes. This case highlights dermatologic findings that should prompt an urgent evaluation for IBC, features that differentiate clinical mimickers from IBC, and potential pitfalls in diagnosing IBC if an improper or incomplete workup is pursued. We also present a review of the literature regarding mimickers of IBC.

Ex vivo confocal microscopy features of common benign lesions that mimic non-melanoma skin cancers: Towards clinical integration.

Ex vivo confocal microscope (EVCM) rapidly images freshly excised tissue at a histopathological resolution. EVCM features of keratinocyte skin cancers are well-established, but those of benign clinical mimickers remain scarce. We describe EVCM features of common benign lesions and compare them with their malignant differentials. EVCM was used to image 14 benign and 3 cancer tissues. We compared EVCM features of benign lesions with corresponding histopathology and with those of keratinocyte cancers. Key features of benign lesions were identified and differentiated from malignant lesions. Elastin and fat appeared prominent in EVCM; while koilocytes and melanin were difficult to identify. Visualization of entire epidermis was challenging due to difficulty of tissue flattening during imaging. Benign lesions can be differentiated from keratinocyte cancers with EVCM. Using EVCM, a rapid, bedside diagnosis and management of skin neoplasms is possible, especially in a remote location without a histopathology lab.

A how-to guide for a precision medicine approach to the diagnosis and treatment of Alzheimer's disease.

The clinical approach to Alzheimer's disease (AD) is challenging, particularly in high-functioning individuals. Accurate diagnosis is crucial, especially given the significant side effects, including brain hemorrhage, of newer monoclonal antibodies approved for treating earlier stages of Alzheimer's. Although early treatment is more effective, early diagnosis is also more difficult. Several clinical mimickers of AD exist either separately, or in conjunction with AD pathology, adding to the diagnostic complexity. To illustrate the clinical decision-making process, this study includes de-identified cases and reviews of the underlying etiology and pathology of Alzheimer's and available therapies to exemplify diagnostic and treatment subtleties. The clinical presentation of Alzheimer's is complex and varied. Multiple other primary brain pathologies present with clinical phenotypes that can be difficult to distinguish from AD. Furthermore, Alzheimer's rarely exists in isolation, as almost all patients also show evidence of other primary brain pathologies, including Lewy body disease and argyrophilic grain disease. The phenotype and progression of AD can vary based on the brain regions affected by pathology, the coexistence and severity of other brain pathologies, the presence and severity of systemic comorbidities such as cardiac disease, the common co-occurrence with psychiatric diagnoses, and genetic risk factors. Additionally, symptoms and progression are influenced by an individual's brain reserve and cognitive reserve, as well as the timing of the diagnosis, which depends on the demographics of both the patient and the diagnosing physician, as well as the availability of biomarkers. The optimal clinical and biomarker strategy for accurately diagnosing AD, common neuropathologic co-morbidities and mimickers, and available medication and non-medication-based treatments are discussed. Real-life examples of cognitive loss illustrate the diagnostic and treatment decision-making process as well as illustrative treatment responses. AD is best considered a syndromic disorder, influenced by a multitude of patient and environmental characteristics. Additionally, AD existing alone is a unicorn, as there are nearly always coexisting other brain pathologies. Accurate diagnosis with biomarkers is essential. Treatment response is affected by the variables involved, and the effective treatment of Alzheimer's disease, as well as its prevention, requires an individualized, precision medicine strategy.

Hemophagocytic Lymphohistiocytosis: A Study of 14 Cases

Context: Hemophagocytic lymphohistiocytosis (HLH) is a hyperactive, but ineffective immune response releasing proinflammatory cytokines, culminating in multiorgan failure and death. Clinical mimickers, lack of gold standard tests, equivocal diagnostic criteria, and limited literature delay the diagnosis. After a comprehensive literature review, we surmise that this is the largest study in India involving 14 patients. Settings and Design: This was a retrospective observational study. Subjects and Methods: Out of 11,272 bone marrow (BM) examinations in 5 years and 3 months, hemophagocytosis was observed in 133 aspirates. Clinical details of these were reviewed. Results: Fourteen patients fulfilling HLH-2004 criteria were included in the study. Infection associated HLH was seen in 71.4% patients. Malignancy and autoimmune disease were seen in 14.2% patients each. Fever was the most common presentation. Splenomegaly was seen in only 21.4% cases. Cytopaenia was present in all patients. Hypertriglyceridaemia was seen in 85.7% patients. Hyperferritinaemia was seen in 92.8% patients. Hemophagocytosis was seen in all patients. Conclusions: HLH should be suspected in cases with cytopaenia and hyperinflammatory markers. Early BM examination, clubbed with appropriate investigations, points to the diagnosis. Newer diagnostic modalities are available however, not much is known about their efficacy. More research in this field will immensely contribute to timely initiation of therapy and improved outcome of HLH.

Risk Factors Predicting Cellulitis Diagnosis in a Prospective Cohort Undergoing Dermatology Consultation in the Emergency Department.

Cellulitis is an infection of the skin and skin-associated structures with many clinical mimickers known collectively as pseudocellulitis. Dermatology or infectious disease consultation is considered the gold standard for diagnosis. We evaluated a prospective cohort of adult patients presenting to the emergency department (ED) with concern for lower extremity cellulitis who received dermatology consultation with conferral of a final diagnosis. Possible risk factors independently associated with cellulitis diagnosis (P<.1) were included in a logistic regression model for prediction of cellulitis diagnosis. Factors having odds ratios with a confidence interval excluding 1 were identified as significant independent predictors. The study identified factors that should be considered in evaluation of patients with suspected uncomplicated lower extremity cellulitis.

33655 Noninvasive, in vivo, characterization of cutaneous metastases using a novel multimodal RCM-OCT imaging device: A case-series

Background: Cutaneous metastases are clinically challenging, requiring an invasive biopsy for confirmation. A novel, noninvasive RCM-OCT device, combines the advantage of high-resolution reflectance confocal microscopy (RCM) images and deeper optical coherence tomography (OCT) images can aid in diagnosis. Objective: Characterize cutaneous metastases using RCM-OCT device. Methods: Seven patients with suspicious cutaneous metastases were consented and imaged with RCM-OCT device, an investigational device. Cutaneous metastases features were defined by comparing with their histopathology. Tumor depths were measured on OCT (under #99-099 and 17-078 IRB protocols) and on H&E-images and correlated using Pearson test. 3D-OCT images were reconstructed to enhance tumor visualization. Results: 6/7 lesions were cutaneous metastases, and 1 was vascular ectasia, on histopathology. Cutaneous metastases appeared as grayish-darkish oval to round structures within the dermis on RCM and OCT images. On RCM, individual tumor cells were seen, enabling identification of even small tumor foci; while, on OCT deeper tumors were detected. Inflammatory cells, dilated vessels, and coarse collagen was identified in the dermis. Pearson correlation had an r2 of 0.38 and a significant P value < .004 for depth measurements. Cutaneous metastases could be differentiated from ecstatic vessels on 3D reconstructed OCT image. Limitation: Small sample size and lack of clinical mimickers. Conclusion: RCM-OCT can detect cutaneous metastases and has potential in aiding noninvasive diagnosis and management.

Causes of parity-related pelvic pain found incidentally on sacroiliac joint MRI: Osteitis condensans ilii and pelvic congestion syndrome

Chronic Pelvic Pain (CPP) is defined as severe pain that persists continuously or intermittently for six months or longer in women, is unrelated to sexual intercourse or menstruation, is likely to cause functional limitation, and requires medical treatment. Osteitis Condensans Ilii (OCI) and Pelvic Congestion Syndrome (PCS) are known causes of CPP. Sacroiliac joint Magnetic Resonance Imaging (MRI) can show different clinical mimickers of sacroiliitis and pelvic pain causes such as OCI and PCS. In this study, our aim was to investigate the frequency of OCI and PCS in patients referred to our clinic for Sacroiliac joint MRI due to low back-pelvic pain and to analyze their association with age, presence of sacroiliitis and multiparity. The the data of 700 female patients who attended the hospital with complaints of low back pain were investigated and it was found that the number of births experienced by the patient significantly correlated with OCI (OR:3.3) and PCS (OR:5.1). Even when MRI shows no evidence of sacroiliitis in a multiparous woman admitted with low back pain, these two differential diagnoses should still be considered by clinicians and radiologists.

Dermoscopic Features of Different Forms of Cutaneous Mastocytosis: A Systematic Review.

The term mastocytosis refers to a heterogeneous group of disorders characterised by accumulation of clonal mast cells in different organs, most commonly in the skin. Little is known about the role of dermoscopy in the diagnostics of mastocytosis. To date, no systematic review on the dermoscopic features of cutaneous mastocytosis has been performed. The aim of this study was to summarise the current knowledge in the field as well as to identify the knowledge gaps to show possible directions for further studies, based on a systematic search of PubMed, Scopus, and Web of Science databases and related references published before 3 January 2022. Dermoscopic features, type of dermoscope, polarisation mode, magnification, and number of cases were analysed. In total, 16 articles were included in this review (3 case series and 13 case reports), analysing 148 patients with different variants of cutaneous mastocytosis; all of the studies analysed had a low level of evidence (V). The main dermoscopic features of urticaria pigmentosa included brown structureless areas, brown lines arranged in a network, and linear vessels distributed in a reticular pattern, with this last finding also being typical of telangiectasia macularis eruptiva perstans. The presence of either circumscribed yellow structureless areas or diffuse yellowish background was a constant pattern of mastocytoma, while nodular, pseudoangiomatous xanthelasmoid, and plaque-type mastocytosis were typified by light-brown structureless areas and/or pigment network, though the first two variants also showed yellow/yellow-orange structureless areas. Finally, pigmented streaks of radial distribution surrounding hair follicles were described to be a pathognomonic dermoscopic feature of pseudoxanthomatous mastocytosis. Although this review shows that the various clinical forms of cutaneous mastocytosis may feature diagnostic dermoscopic clues, it also underlines the need for further investigation as several relevant data are missing, including evaluation of dermoscopic pattern according to anatomical locations or “lesion age”, studies on rare mastocytosis variants, evaluation of the prognostic role of dermoscopy in the context of systemic involvement, and comparative analyses with common clinical mimickers.

Dermoscopy as a Supportive Tool to Differentiate Lichen Amyloidosus From Clinical Mimickers.

Dermoscopy as a Supportive Tool to Differentiate Lichen Amyloidosus From Clinical Mimickers.

Non-invasive, in vivo, characterization of cutaneous metastases using a novel multimodal RCM-OCT imaging device: a case-series.

Cutaneous metastases (CM) diagnosis is clinically challenging, requiring an invasive biopsy for confirmation. A novel, RCM-OCT device combines the advantage of horizontal high-resolution reflectance confocal microscopy (RCM) images and vertical deeper optical coherence tomography (OCT) images to aid in non-invasive diagnosis of CM from breast cancers. Characterize CM from breast cancers using RCM-OCT device. Seven patients suffering from breast cancers with suspicious CM were consented and imaged with RCM-OCT device. CM features were defined by comparing with histopathology. Tumour depths were measured on OCT and on H&E-images and correlated using statistical analysis Pearson test. 3D-OCT images were reconstructed to enhance tumour visualization. 6/7 lesions were CM from breast cancers, and one was vascular ectasia, on histopathology. CM appeared as greyish-darkish oval to round structures within the dermis on RCM and OCT-images. On RCM, individual tumour cells were seen, enabling identification of even small tumour foci; while, on OCT deeper tumours were detected. Inflammatory cells, dilated vessels and coarse collagen were identified in the dermis. Pearson correlation had an r2 of 0.38 and a significant P-value <0.004 for depth measurements. CM from breast cancers could be differentiated from ecstatic vessels on 3D-reconstructed OCT image. Small sample size and lack of clinical mimickers. RCM-OCT can detect CM and has potential in aiding non-invasive diagnosis and management.

Line-field confocal optical coherence tomography: a new tool for non-invasive differential diagnosis of pustular skin disorders.

BackgroundThe spectrum of pustular skin disorders (PSD) is large and particularly challenging, including inflammatory, infectious and amicrobial diseases. Moreover, although pustules represent the unifying clinical feature, they can be absent or not fully developed in the early stage of the disease. The line‐field confocal optical coherence tomography (LC‐OCT) is a recently developed imaging technique able to perform a non‐invasive, in vivo, examination of the epidermis and upper dermis, reaching very high image resolution and virtual histology.ObjectivesWe aimed to investigate the potentialities of LC‐OCT in the non‐invasive differential diagnosis of a series of 11 PSD with different aetiology, microscopic features, body location and incidence rates.Materials and MethodsComplete LC‐OCT imaging (i.e. 2D/3D frames, videos) was performed on a total of 19 patients (10 females and 9 males) aged between 35 and 79 years. Images were blindly evaluated and compared with corresponding histopathologic findings.ResultsThe LC‐OCT imaging was able to detect with high accuracy the pustule structure including shape, margins, morphology and cellular content, along with peculiar epidermal and adnexal alterations in each condition, including: Acute Generalized Exanthematous Pustulosis, Generalized pustular psoriasis, Generalized pustular figurate erythema, Subcorneal Pustular Dermatosis, Intraepidermal IgA pustulosis, Palmoplantar pustulosis, Palmoplantar pustular psoriasis. Herpetic whitlow, Acrodermatitis continua of Hallopeau, Vesicopustular Sweet syndrome and Vesicopustular Eosinophilic cellulitis, with pustular appearance, were also compared.ConclusionsThe new LC‐OCT can represent a rapid, non‐invasive and painless tool which can help differentiating among PSD of different aetiology and microscopic morphology in clinical mimickers in daily practice.

Cellulitis: A Review of Current Practice Guidelines and Differentiation from Pseudocellulitis.

Cellulitis, an infection involving the deep dermis and subcutaneous tissue, is the most common reason for skin-related hospitalization and is seen by clinicians across various disciplines in the inpatient, outpatient, and emergency room settings, but it can present as a diagnostic and therapeutic challenge. Cellulitis is a clinical diagnosis based on the history of present illness and physical examination and lacks a gold standard for diagnosis. Clinical presentation with acute onset of redness, warmth, swelling, and tenderness and pain is typical. However, cellulitis can be difficult to diagnose due to a number of infectious and non-infectious clinical mimickers such as venous stasis dermatitis, contact dermatitis, eczema, lymphedema, and erythema migrans. Microbiological diagnosis is often unobtainable due to poor sensitivity of culture specimens. The majority of non-purulent, uncomplicated cases of cellulitis are caused by β-hemolytic streptococci or methicillin-sensitive Staphylococcus aureus, and appropriate targeted coverage of this pathogen with oral antibiotics such as penicillin, amoxicillin, and cephalexin is sufficient. Even with rising rates of community-acquired methicillin-resistant Staphylococcus aureus, coverage for non-purulent cellulitis is generally not recommended.

M023 AN UNCOMMON MIMICKER OF ANAPHYLAXIS

Anaphylaxis is a life-threatening allergic reaction for which physicians should have a high level of suspicion. Prompt diagnosis and treatment are crucial but can be complicated by clinical mimickers. We describe a patient who presented with tetany secondary to hypocalcemia that was initially diagnosed and treated as anaphylaxis.

Dermatoscopy of nodular/plaque-type primary cutaneous T- and B-cell lymphomas: A retrospective comparative study with pseudolymphomas and tumoral/inflammatory mimickers by the International Dermoscopy Society

Limited data on dermatoscopy of nodular/plaque-type T-/B-cell primary cutaneous lymphomas (PCLs) is available. To describe dermatoscopic features of nodular/plaque-type PCLs, comparing them with those of clinical mimickers (pseudolymphomas, tumors, and inflammatory lesions) and investigating possible differences according to histologic subtypes. Participants were invited to join this retrospective, multicenter case-control study by submitting histologically/immunohistochemically confirmed instances of nodular/plaque-type PCLs and controls. Standardized assessments of the dermatoscopic images and comparative analyses were performed. A total of 261 lesions were included (121 PCLs and 140 controls). Orange structureless areas were the strongest PCL dermatoscopic predictor on multivariate analysis compared with tumors and noninfiltrative inflammatory dermatoses. On the other hand, a positive association was found between PCLs and either unfocused linear vessels with branches or focal white structureless areas compared with infiltrative inflammatory dermatoses, whereas white lines were predictive of PCLs over pseudolymphomas. Differences in the vascular pattern were also seen between B- and T-cell PCLs and among B-cell PCL subtypes. Retrospective design and the lack of a dermatoscopic-pathologic correlation analysis. Nodular/plaque-type PCLs display dermatoscopic clues, which may partially vary according to histologic subtype and whose diagnostic relevance depends on the considered clinical differential diagnoses.

Clinical mimickers of epidermoid cyst in scalp: a retrospective histopathological study

Background: Cystic lesions of the scalp with a clinical diagnosis of an epidermoid cyst are encountered in clinical practice. However, these lesions had a different diagnostic interpretation on histopathology examination. Therefore our study focused on the lesions clinically resembling the presentation of epidermoid cyst in the scalp region. Materials and Methods: Forty-one cases of scalp lesions with a clinical diagnosis of epidermoid cyst over 2 years were reviewed. Details of the patients such as clinical diagnosis, age, gender, duration, gross findings, and histopathology diagnosis were obtained from the medical and histopathology records. Results: Epidermoid cysts diagnosed both clinically and on histopathology examination accounted for 29.26% whereas the clinical mimickers constituted 70.73%. The mean age of the patient was 35-years with an equal sex ratio. The commonest location was the parietal region (41.37%). Benign and malignant lesions consisted of 97.56% and 2.4% respectively. A trichilemmal cyst was the most common clinical mimicker diagnosed. Conclusions: Clinicians should be aware of wide differential diagnosis of epidermoid cyst in the scalp region as the management and outcome vary with each lesion. Histopathology examination proved to be a diagnostic tool in differentiating these lesions.

LB780 Risk factors predicting Cellulitis diagnosis in a prospective cohort undergoing dermatology consultation in the Emergency Department

Cellulitis is a skin and skin-associated structure infection with many clinical mimickers called pseudocellulitis. Dermatology consultation is considered the gold standard for diagnosis. A prospective cohort of adult patients presenting to the emergency department with concern for lower extremity cellulitis received dermatology consultation with conferral of a final diagnosis. Patients with signs of complicated cellulitis, such as abnormal vital signs, or infection overlying hardware, animal bites, or sites of recent surgery were excluded.

Adult late-onset atopic dermatitis presenting as cutaneous lupus in a male patient

BackgroundAdult-onset atopic dermatitis (AD) diagnosis is very challenging as it presents with clinical heterogeneity and can mimic a broad of differential diagnoses such as mycosis fungoid and psoriasis. Herein, we report a lupus-like presentation of adult-onset AD. Clinical caseA 32-year-old man with a history of asthma presented to our department with a – lupus like – malar rash. Cutaneous lupus was suspected, but neither clinical, nor paraclinical or immunological assessment were in favor of the disease, skin biopsy revealed epidermal spongiosis, and eosinophilic infiltrate which, together with the patient's personal history and laboratory abnormalities, allowed the diagnosis of late-onset AD. Treatment with topical corticosteroids on the body and tacrolimus on the face was started, with good improvement. ConclusionAdult AD can simulate cutaneous lupus. Recognition of the clinical mimickers of AD is crucial for an accurate diagnosis.