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1.
Indian J Pathol Microbiol ; 67(1): 36-45, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38358186

RESUMO

Context: : Head and neck squamous cell carcinomas (HNSCCs) are the sixth most frequent malignancy in the world. Epidermal growth factor receptors (EGFRs) are members of Erb B family of receptors. EGFR is known to act as a driver of tumorigenesis in various carcinomas. Over expression of EGFR in HNSCC is associated with poor prognosis and resistance to radiotherapy. It is a useful prognostic marker, marker for response to therapy, and also a therapeutic target. Aim: To study the association of the known prognostic variables with EGFR expression in HNSCCs and to correlate it with the clinical outcome. Settings and Design: Cross-sectional observational study. Materials and Methods: A total of 170 patients of HNSCC were evaluated for EGFR expression and followed up for at least two years, with correlation of EGFR expression with various histopathological factors and their clinical outcome. Statistical Analysis Used: : Chi-square test. Results: The expression of EGFR in HNSCC in this study population was 88.82%. Statistical significance was noted between EGFR reactivity and age of the patient, its histological grade and perineural invasion. Statistical significance was also noted between EGFR reactivity and recurrence of malignancy as well as the site of recurrence. Conclusion: EGFR expression in patients with HNSCC is a poor prognostic biomarker and has a comparatively lower survival outcome as compared to non-EGFR expressing HNSCC cases. Hence, it will be helpful for all those patients diagnosed with HNSCC to ideally undergo an additional EGFR immunohistochemical evaluation, which, in turn, will help the oncologists in management of the tumor with anti-EGFR therapy combined with radiotherapy, to obtain a better response and a survival outcome.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Prognóstico , Carcinoma de Células Escamosas/diagnóstico , Estudos Transversais , Neoplasias de Cabeça e Pescoço/diagnóstico , Receptores ErbB/genética
2.
Postgrad Med ; 135(4): 345-351, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36287784

RESUMO

BACKGROUND: The systemic immune-inflammation index (SII) is a novel parameter and its role in the prognosis of sepsis has never been explored previously. METHODS: We retrospectively assessed 267 patients with blood-culture confirmed sepsis. Clinical and laboratory data recorded at intensive care unit (ICU) admission were analyzed. Outcomes of interest included in-hospital mortality and length-of-stay (LOS) in the ICU. Sequential Organ Failure Assessment (SOFA) scores, SII, neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR) were calculated. Multivariable regression analysis was used to identify independent predictors of LOS and mortality. Area under receiver operator characteristic (AUROC) curves were used to determine optimum cutoffs, and the incremental effect of SII on the SOFA score was assessed using model discrimination and calibration properties. RESULTS: There were 76 (28.5%) non-survivors. SII, NLR, and PLR were independent predictors of sepsis mortality, with adjusted odds ratios of 1.51 (1.24-1.84), 1.67 (1.30-2.13) and 1.24 (1.11-1.39). SII and SOFA score were independent predictors of LOS. SII had an AUROC of 0.848, and the optimum cutoff was 564 with a sensitivity and specificity of 85.5% and 71.2%. The addition of SII to the model had a significant incremental effect on the predictive ability of SOFA score (Net Reclassification Index = 0.084, P = 0.025; Integrated Discrimination Index = 0.056, P = 0.001). CONCLUSION: The SII is an inexpensive parameter that can be used in addition to clinical sepsis scores to improve the accuracy of patient assessment.


Assuntos
Sepse , Humanos , Estudos Retrospectivos , Sepse/diagnóstico , Inflamação , Prognóstico , Tempo de Internação
3.
J Microsc Ultrastruct ; 11(4): 214-219, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38213652

RESUMO

Context: Tumor microenvironment is emerging as a critical factor for progression of breast cancer. Tumor-associated macrophages (TAMs) play an important role in promoting tumor growth. Aim: This study was aimed at correlation of number density (ND) of TAMs with invasive ductal carcinoma (IDC) grading utilizing an image morphometric technique. We also sought to compare the TAMs and ND in the tumoral area and stromal region. We also explored the relationship between the clinical and pathological prognostic parameters. Subjects and Methods: The study included 75 cases of IDC that had undergone modified radical mastectomy. The Institutional Ethics Committee approved the study. Samples were classified as Grade 1, 2, and 3. Cases were graded as per the modified Bloom and Richardson criterion. Mean with standard deviation was calculated for each group. We utilized CD68 and CD163 immunostained sections for determining the ND of TAMs. TAMs were evaluated using computerized digital photomicrograph system with image analyzing software. ND was defined as the number of TAMs in total number of TAMs in five high-power fields/total area of five fields. ND was calculated separately in tumor and tumor stroma (TS). Estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2/neu (HER2/neu) were scored in accordance with recommendations. Ki-67 was scored as per the recommended guidelines. Statistical Analysis Used: Data were tabulated in Microsoft Excel. SPSS version 20.0 (IBM Corp., Armonk, NY, USA) was used for statistical analysis. To determine the relationship between macrophage density and clinicopathologic parameters, we used the independent t-test. To determine the differences in the parameters, analysis of variance (ANOVA) was utilized. Results: Age of the patients ranged from 34 to 58 years (mean: 55.5). One-way ANOVA between various grades of tumor indicating significant differences in terms of CD68 and CD163 densities in tumor and stroma (P < 0.0001). i.e., significant increased density of CD68 and CD163 was observed in Grade 3 tumor as compared to other two groups. A greater histological grade, ER, PR negative status, and a high Ki-67 index were all associated with TAM ND. There was no relation to HER2/neu status. Result of unpaired t-test indicates increased density in stroma as compared to tumor among various grades of IDC. Conclusions: We analyzed images with a software using photographs of the stained slides. This helped in quantitative analysis of TAMs on the CD68 and CD163 stained sections. This approach standardizes and reproducibly counts TAMs per unit area. We found significant difference between the number densities of TAMs in grades of invasive breast carcinoma. There were statistically significant differences in numerical densities of TAMs with ER, PR negativity, and Ki-67. There was no correlation with HER2/neu. Densities of CD68 and CD163 densities are more prevalent in TS as compared to intratumoral region.

4.
Sci Rep ; 12(1): 16420, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36180472

RESUMO

Deep neural networks (DNNs) have shown success in image classification, with high accuracy in recognition of everyday objects. Performance of DNNs has traditionally been measured assuming human accuracy is perfect. In specific problem domains, however, human accuracy is less than perfect and a comparison between humans and machine learning (ML) models can be performed. In recognising everyday objects, humans have the advantage of a lifetime of experience, whereas DNN models are trained only with a limited image dataset. We have tried to compare performance of human learners and two DNN models on an image dataset which is novel to both, i.e. histological images. We thus aim to eliminate the advantage of prior experience that humans have over DNN models in image classification. Ten classes of tissues were randomly selected from the undergraduate first year histology curriculum of a Medical School in North India. Two machine learning (ML) models were developed based on the VGG16 (VML) and Inception V2 (IML) DNNs, using transfer learning, to produce a 10-class classifier. One thousand (1000) images belonging to the ten classes (i.e. 100 images from each class) were split into training (700) and validation (300) sets. After training, the VML and IML model achieved 85.67 and 89% accuracy on the validation set, respectively. The training set was also circulated to medical students (MS) of the college for a week. An online quiz, consisting of a random selection of 100 images from the validation set, was conducted on students (after obtaining informed consent) who volunteered for the study. 66 students participated in the quiz, providing 6557 responses. In addition, we prepared a set of 10 images which belonged to different classes of tissue, not present in training set (i.e. out of training scope or OTS images). A second quiz was conducted on medical students with OTS images, and the ML models were also run on these OTS images. The overall accuracy of MS in the first quiz was 55.14%. The two ML models were also run on the first quiz questionnaire, producing accuracy between 91 and 93%. The ML models scored more than 80% of medical students. Analysis of confusion matrices of both ML models and all medical students showed dissimilar error profiles. However, when comparing the subset of students who achieved similar accuracy as the ML models, the error profile was also similar. Recognition of 'stomach' proved difficult for both humans and ML models. In 04 images in the first quiz set, both VML model and medical students produced highly equivocal responses. Within these images, a pattern of bias was uncovered-the tendency of medical students to misclassify 'liver' tissue. The 'stomach' class proved most difficult for both MS and VML, producing 34.84% of all errors of MS, and 41.17% of all errors of VML model; however, the IML model committed most errors in recognising the 'skin' class (27.5% of all errors). Analysis of the convolution layers of the DNN outlined features in the original image which might have led to misclassification by the VML model. In OTS images, however, the medical students produced better overall score than both ML models, i.e. they successfully recognised patterns of similarity between tissues and could generalise their training to a novel dataset. Our findings suggest that within the scope of training, ML models perform better than 80% medical students with a distinct error profile. However, students who have reached accuracy close to the ML models, tend to replicate the error profile as that of the ML models. This suggests a degree of similarity between how machines and humans extract features from an image. If asked to recognise images outside the scope of training, humans perform better at recognising patterns and likeness between tissues. This suggests that 'training' is not the same as 'learning', and humans can extend their pattern-based learning to different domains outside of the training set.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , Humanos , Técnicas Histológicas , Percepção
5.
Med J Armed Forces India ; 78(Suppl 1): S96-S104, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36147411

RESUMO

Background: Colorectal cancer (CRC) is one of the commonest cancers worldwide, with incidence rates in India being around 4%. It is a heterogeneous disease with multiple established prognostic factors. Ten to fifteen percent originate from microsatellite instability (MSI) pathway, characterized by defect in mismatch repair (MMR) gene. Identification of MMR defective protein is relevant for diagnosis, prognosis, and prediction. Certain clinical and histological features are known to be associated with defective MMR genes. The objectives of this study are to find the prevalence of MSI in CRC to identify features associated with MSI and assess the value of histopathology in predicting MSI. Methods: We evaluated various clinical and histological parameters for identifying prognostically favorable colon cancers in a tertiary hospital. One hundred fifty colon cancers were evaluated, and MSI status was correlated with clinicopathologic variables. Results: The prevalence of MSI in CRC was found to be 11.3%. The factors associated with MSI were tumor differentiation, stage, tumor site, tumor size, tumor-infiltrating lymphocytes, Crohn's-like lymphoid reaction, and dirty necrosis. We have defined a "P" score for prediction of MSI using the clinicohistological parameters, which could be used to select patients who are to be tested for MSI. Conclusion: Assessment of clinical and histopathological features will help in patient stratification and selection of patients for MSI testing. The evaluation is economical, reproducible, and easy to apply.

6.
Med J Armed Forces India ; 78(3): 291-295, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35855707

RESUMO

Background: Idiopathic steroid-resistant nephrotic syndrome (iSRNS) is a common problem in pediatric nephrology. About 10%-20% of children with nephrotic syndrome have iSRNS and almost 50 percent progress to end-stage renal disease. Very few studies have tried to study the histopathological spectrum, correlate clinical features, renal biopsy patterns and treatment outcome in children presenting with iSRNS in India. In this study, we compared the histopathologic distribution of different subtypes of glomerular morphologic patterns in iSRNS and the clinical and biochemical parameters at the time of diagnosis and outcome of patients after immunosuppressive therapy. Methods: It is a retrospective cross-sectional study involving review of records of all children with iSRNS presenting to our pediatric nephrology OPD who underwent renal needle biopsy and followed-up for a period of atleast six months post biopsy. Histopathological subtypes were correlated with clinical features (viz. age of onset, gender, oliguria, microscopic hematuria, hypertension, serum creatinine at presentation, serum total protein, serum albumin, 24 h urine protein, persistent proteinuria after 12 weeks of calcineurin inhibitor therapy, and progress to end stage renal disease (ERSD), if any, outcome. Result: It was found that minimal change disease (MCD) was overall the most common cause of iSRNS. These patients have a significantly greater incidence of remission with immunosuppression as compared with focal segmental glomerulosclerosis (FSGS) and IgA nephropathy subgroup. Conclusion: Kidney biopsy is of prognostic value in children with iSRNS. The prognosis of children with SRNS owing to MCD is much better than with other nephropathy.

7.
Med J Armed Forces India ; 78(3): 327-332, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35855718

RESUMO

Background: Lupus Nephritis (LN) is a major and frequent manifestation of Systemic Lupus Erythematosus (SLE), an autoimmune disease. Renal biopsy has a pivotal role in the diagnosis, prognosis, and management of the LN. The aim of this study was to count the mesenchymal interstitial cells utilizing CD34 immunohistochemistry (IHC) and morphometric analysis, correlate them with clinical parameters, class, activity, and chronicity indices and see if it can predict the course of the disease. Methods: A total of 32 renal biopsy blocks were analyzed by H&E stain, special stains, and CD34 IHC. Microvasculature density and interstitial stem cells were highlighted by CD34. These were then counted using a previously standardized computerized digital photomicrograph system (Dewinter Optical Inc) and manual count, respectively. Results: Out of the 32 cases, Lupus class 3 comprised of 11 (34.38%) cases, class 4 comprised of 16 (50%) cases, and mixed class 4 + 5 had 5 (15.62%) cases. It was found that CD34 expression in the microvasculature (for both microvascular density and mean vascular lumen diameter) decreased in patients of Lupus Nephritis with higher disease activity (p < 0.05). Although not statistically significant, the number of interstitial stem cells increased with lower disease activity. A statistical significance was found between serum total protein, serum albumin, and serum creatinine among the three groups of LN. Conclusion: Immunohistochemical staining of renal biopsy with CD34 may be used as a surrogate marker of disease activity in Lupus Nephritis patients.

8.
Med J Armed Forces India ; 77(2): 194-199, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33867637

RESUMO

BACKGROUND: Morphometry has now become a useful adjunct to the diagnostic armamentarium of light, immunofluorescence, and electron microscopy, as it provides a deep insight into quantitative parameters of nephropathies. There has been a limited study on its utility especially in diagnosing pediatric renal diseases. This study is probably the first in India to assess the contribution of this diagnostic modality in pediatric renal disease to the best of authors' knowledge. METHODS: It's a retrospective cross-sectional study covering a period of 05 years at a tertiary care hospital. The study includes 28 cases of pediatric (age till 14 years) nephropathies. The diseases were divided into two groups-nephrotic presentation and nephritic presentation. Glomerular morphometry was performed and mean was calculated for Bowman's capsule area, glomerular capillary tuft area, and Bowman's space area; for the three groups, respectively. Renal parameters serum creatinine, blood urea, 24 h urine protein were studied along with hemoglobin and serum cholesterol for the cases. Data were analyzed using SPSS software, version 25, for one-way ANOVA comparing mean in the three groups. RESULTS: We found a positive and significant correlation between Bowman's capsule area with proteinuria, blood urea, and serum creatinine. There was positive and significant correlation between glomerular capillary tuft area and serum creatinine and Bowman's space area and proteinuria in both the groups. CONCLUSION: Glomerular morphometry may contribute to the diagnosis of some glomerulopathies and the association between glomerular morphometric parameters and laboratory data may promote better understanding of the prognosis of these patients.

9.
Indian J Hematol Blood Transfus ; 37(4): 600-608, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33776267

RESUMO

Platelet indices are inexpensive, easily accessible parameters and potentially useful prognostic indicators in sepsis. In this study we explore the differences in platelet indices and their kinetics between sepsis survivors and non-survivors. A retrospective cohort-study of 97 cases of culture-positive sepsis at a tertiary-care center in North India. Demographics, clinical and laboratory parameters at admission were assessed. Platelet count (PLT), mean-platelet-volume (MPV), platelet-distribution-width (PDW) and plateletcrit (PCT) on admission, and third, fifth and last days of hospitalization were analyzed. Fractional change in platelet indices (ΔMPV72h, ΔPDW72h, ΔPCT72h, and ΔPLT72h) by day-3 were calculated. Unpaired and paired t-tests were used to compare survivors with non-survivors, and to study the change in platelet indices with time. Logistic regression was used for multivariate analysis. ROC-curves and optimum cut-offs to predict mortality were obtained. There were 64 survivors. Non-survivors had significantly higher ΔMPV72h, ΔPDW72h, day-1 MPV and PDW, and lower ΔPLT72h. MPV and PDW increased, and PLT decreased with time among non-survivors. Trends were reversed in survivors. Only MPV and PDW showed significant change by day-3. Both were independent predictors of mortality on multivariate analysis, alongside ΔMPV72h and ΔPLT72h. On ROC analysis, MPV, PDW, ΔMPV72h, ΔPDW72h and ΔPLT72h effectively predicted mortality. Cut-off for MPV was 10.25 fL (sensitivity = 93.9%, specificity = 60.9%), and PDW, 12.6% (sensitivity = 84.8%, specificity = 51.6%). A rise in MPV and a fall in PLT was associated with mortality in this study. MPV and PDW values at admission are effective predictors of mortality and may be used in conjunction with traditional parameters.

10.
Med J Armed Forces India ; 76(2): 161-165, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32476713

RESUMO

BACKGROUND: Hypertension encountered during pregnancy could be the first sign of a preexisting pathology that can significantly attribute to unfavorable maternal, fetal, and neonatal outcomes. Resolving hypertensive disorders at an early age may not alter the course and proficiency of the disease, but timely detection and treatment can not only prevent hypertensive crisis but also alter unfavorable fetal outcomes. Ipso facto, an early cataloging plays an essential role in predicting the outcome of pregnancy, both for mother and baby. Platelet indices correlate with functional status of platelets and are an emerging risk marker for detecting an impending adverse outcome in pregnancy-induced hypertension (PIH). The aim of this study was to analyze the consociation between platelet indices and severity of PIH. METHODS: A prospective hospital-based study was undertaken on 100 cases diagnosed with PIH (preeclampsia [PE; 88 cases] and eclampsia [12 cases and 100 controls]). RESULTS: Most cases occurred in the age group of 22-26 years (43.3%) and in primigravidae (55.8%). Analysis of platelet volume indices (PVI) indicated mean platelet volume (MPV), platelet distribution width (PDW), and platelet-large cell ratio (P-LCR) as significant risk factors for developing hypertensive crisis. This was in concordance with the elevated blood pressures. CONCLUSION: The study concludes that platelet indices are raised in patients who have PIH as compared with normal pregnancies.

13.
J Hum Reprod Sci ; 12(3): 255-257, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576085

RESUMO

Robertsonian translocation is a subtype of balanced translocation involving two acrocentric chromosomes. Individuals who are carrier of this abnormality are at increased risk of infertility or bad obstetric history. This case is reported with the aim to describe a male who presented with nonobstructive azoospermia at a tertiary care center. The individual was phenotypically normal but carrier of a Robertsonian translocation of two acrocentric chromosomes. With this literature, we emphasize that conventional cytogenetic is an essential diagnostic tool for screening genetic factors in infertility.

14.
J Lab Physicians ; 11(3): 281-283, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31579230

RESUMO

Plasma cell (PC) neoplasm (PCN) with varied morphology has been described in the literature. The majority of clonal proliferation of PCs is composed of easily recognizable morphology in the bone marrow (BM). However, few cases may cause diagnostic complexity, as they exhibit varied cytological and architectural heterogeneity which may pose problem in morphological diagnosis and require the use of ancillary techniques like immunohistochemistry (IHC). We illustrate here two such cases of PCN with varied morphology in BM aspirate, in the form of clustering/rosetting and multiple clear cytoplasmic vacuoles, respectively, leading to varied differential diagnosis. However, later, the histopathological features on BM biopsy findings were relatively characteristic and IHC confirmed the final diagnosis. The morphological variants documented in both these cases are exceptional and representative of the various forms of atypical PCs.

15.
Indian J Dermatol ; 62(4): 431-433, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28794561
16.
Indian Dermatol Online J ; 7(2): 93-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27057488

RESUMO

Acne fulminans (AF) is a very rare severe form of acne seen in young males, characterized by a sudden and explosive onset of hemorrhagic pustules and ulceration on the trunk, systemic features in the form of fever, polyarthropathy, malaise, erythema nodosum and painful osteolytic bone involvement with leukocytosis, and an elevated erythrocyte sedimentation rate. Conventional treatment of AF includes corticosteroids or immunosuppressive agents for the initial phase followed by isotretinoin. Active hepatitis B infection with a high viral load precludes the administration of any immunosuppressive drugs. We present the case of an 18-year-old girl with a history of occasional acne who presented with AF of sudden onset following administration of interferon-alpha-2a for her recently detected hepatitis B infection. Management of hepatitis B was withheld in view of her general condition. The patient was managed with low dose isotretinoin with subsidence of lesions. AF in a young female precipitated by interferon and its management with isotretinoin in the presence of active hepatitis B infection make the case unique.

17.
Indian Dermatol Online J ; 7(2): 139-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27057507
19.
Med J Armed Forces India ; 72(1): 67-70, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26900226

RESUMO

BACKGROUND: Nevus Lipomatosis Cutaneous Superficialis (NLCS) is a rare, benign hamartomatous lesion characterized by the ectopic presence of mature adipocytes in the reticular dermis not associated with the underlying subcutaneous tissue. Two clinical forms-classical and solitary occur. The solitary form is relatively uncommon, due to which these lesions are commonly clinically misdiagnosed. The aim was to study the clinical and histopathological features of the solitary type of NLCS. METHODS: Seven cases of histopathologically documented solitary type of NLCS which presented at our institute between August 2013 and June 2014 were retrospectively analysed for clinical data and histopathological findings. Haematoxylin and Eosin (H&E) and Elastic Van Gieson (EVG) stained slides were studied in all cases. RESULTS: Mean age of the patients was 42.5 years. These lesions were more common in adult females (5/7). Thigh was the commonest location (4/7). The mean duration of these lesions was 2.0 years. Clinical diagnosis was papilloma (4/7) and acrochordon (3/7). Histopathology revealed the presence of varying amounts of mature ectopic adipocytes in the dermis located around dilated, ectactic blood vessels. Disorganised dermal collagen bundles and atrophic pilosebaceous units were seen. CONCLUSION: This study is a first from the Indian subcontinent and highlights the need for awareness of this rare clinical condition both by the dermatologists and the surgeons. Histopathology is essential for diagnosis as clinically they may mimic papillomas or skin tags. An early diagnosis may permit a more conservative resection of the tumour.

20.
Artigo em Inglês | MEDLINE | ID: mdl-26515837

RESUMO

BACKGROUND: An increase in number of melanocytes in the basal cell layer of the epidermis is an important feature in many disorders of hyperpigmentation. In this study, we attempted an objective evaluation of the linear density of melanocytes and keratinocytes, along with other epidermal characteristics, in periorbital hyperpigmentation using immunohistochemistry and morphometric techniques. METHODS: Melanocytes and epidermal parameters were assessed by digital morphometry in 30 newly diagnosed cases of periorbital hyperpigmentation and 14 controls from the post-auricular region. Melanocytes were labelled with the immunohistochemical stains, Melan-A and tyrosinase. We studied the linear keratinocyte density, mean linear melanocyte density, ratio of melanocytes to keratinocytes, the ratio between inner and outer epidermal length, maximum epidermal thickness and minimum epidermal thickness. RESULTS: Melan-A expression of melanocytes showed strong positive correlation (r=0.883) with the tyrosinase expression. Mean linear melanocyte density was 24/mm (range: 13-30/mm) in cases and 17/mm (13-21/mm) in controls and this difference was statistically significant (P<0.001). The mean ratio of melanocyte to keratinocyte was 0.22 (0.12-0.29) in cases and 0.16 (0.12-0.21) in controls; again, this difference was statistically significant (P<0.001). There was a mild negative correlation with linear keratinocyte density (r=-0.302) and the ratio between inner and outer epidermal length (r=-0.456). However, there were no differences in epidermal thicknesses. LIMITATIONS: There were fewer control biopsies than optimal, and they were not taken from the uninvolved periorbital region. CONCLUSION: Mean linear melanocyte density and the ratio of melanocytes to keratinocytes is increased in cases with periorbital hyperpigmentation. It is, therefore, likely that increased melanocyte density may be the key factor in the pathogenesis of periorbital hyperpigmentation.


Assuntos
Epiderme/patologia , Dermatoses Faciais/patologia , Hiperpigmentação/patologia , Melanócitos/química , Melanócitos/patologia , Adolescente , Adulto , Estudos de Casos e Controles , Contagem de Células , Olho , Feminino , Humanos , Imuno-Histoquímica , Queratinócitos/patologia , Antígeno MART-1/análise , Masculino , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/análise , Adulto Jovem
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