Presence of hyphae in chromoblastomycosis examinations: an enigma to be solved

The detection of muriform cells in direct mycological or anatomopathological examination is considered pathognomonic for chromoblastomycosis. The morphological aspect that these fungal structures acquire were called “Borelli spiders”, when associated with hyphae. Reports of this association have been described for decades, initially related to more pathogenic agents of this mycosis. More recent studies have shown aspects related to the host's immunity that participate in this process, as well as an association with a worse disease prognosis. The present study discloses the findings of complementary examinations with the presence of “Borelli’s spiders” in a patient diagnosed with chromoblastomycosis.     

Accuracy of direct examination and culture as compared to the anatomopathological examination for the diagnosis of chromoblastomycosis: a systematic review

BackgroundChromoblastomycosis is a skin infection caused by dematiaceous fungi that take the form of muriform cells in the tissue. It mainly manifests as verrucous plaques on the lower limbs of rural workers in tropical countries.ObjectivesThe primary objective of this review is to evaluate the accuracy of diagnostic methods for the identification of chromoblastomycosis, considering the histopathological examination as the reference test.MethodsMEDLINE, LILACS and Scielo databases were consulted using the terms “chromoblastomycosis” AND “diagnosis”. The eligibility criteria were: studies that evaluated the accuracy of tests for the diagnosis of chromoblastomycosis. Eleven studies were selected. Statistical analysis included the calculation of sensitivity and specificity of the diagnostic methods.ResultsConsidering the histopathological examination as the reference test, the culture showed a sensitivity (S) of 37.5% - 90.9% and a specificity (Sp) of 100%; while direct mycological examination showed S = 50% - 91.6% and Sp of 100% . Considering the culture as the reference test, the serology (precipitation techniques) showed S of 36% - 99%; and Sp of 80% - 100%; while the intradermal test showed S of 83.3% - 100% and Sp of 99.4% - 100%.Study limitationsThe small number of studies and very discrepant sensitivity results among them do not allow the calculation of summary measures through a meta-analysis.ConclusionsDirect mycological examination, culture, intradermal test and serology show sensitivity and specificity values ??for the diagnosis of chromoblastomycosis with no significant difference between the studies.     

Study of tissue inflammatory response in different mice strains infected by dematiaceous fungi Fonsecaea pedrosoi

Background:Diseases caused by melanized fungi include mycetoma, chromoblastomycosis and phaeohyphomycosis. This broad clinical spectrum depends on the dynamic interactions between etiologic agent and host. The immune status of the host influences on the development of the disease, as, an exemple. phaeohyphomicosis is more frequently observed in immunocompromised patients.Objectives:Examine the histological inflammatory response induced by Fonsecaea pedrosoi in several different strains of mice (BALB/c, C57BL/6, Nude and SCID, and reconstituted Nude).Methods:Fonsecaea pedrosoi was cultivated on agar gel and a fragment of this gel was implanted subcutaneously in the abdominal region of female adult mice. After infection has been obtained, tissue fragment was studied histopathologically.Results:There were significant changes across the strains, with the nodular lesion more persistent in Nude and SCID mice, whereas in immunocompetent mice the lesion progressed to ulceration and healing. The histopathological analysis showed a significant acute inflammatory reaction which consisted mainly of neutrophils in the initial phase that was subsequently followed by a tuberculoid type granuloma in immunocompetent mice.Study limitations:There is no a suitable animal model for chromoblastomycosis.Conclusions:The neutrophilic infiltration had an important role in the containment of infection to prevent fungal spreading, including in immunodeficient mice. The fungal elimination was dependent on T lymphocytes. The re-exposure of C57BL/6 mice to Fonsecaea pedrosoi caused a delay in resolving the infection, and appearance of muriform cells, which may indicate that re-exposure to fungi, might lead to chronicity of infection.     

Electron microscopy and morphometry enhances differentiation of epidermolysis bullosa subtypes. With normal values for 24 parameters in skin

Electron microscopy combined with morphometry was used to establish values for 24 parameters in normal skin. These results were compared with those similarly obtained from samples of epidermolysis bullosa with a view to facilitating classification of the disease. Six of the eight subtypes of epidermolysis bullosa investigated could be differentiated. Four subtypes showed values for structural components in intact skin which were outside the normal range: (1) epidermolysis bullosa simplex generalisata gravis (hemidesmosomes); (2) epidermolysis bullosa dystrophica Pasini and (3) Cockayne-Touraine (anchoring fibrils); and (4) epidermolysis bullosa acquisita (anchoring fibrils, hemidesmosomes, and lamina lucida and lamina densa aspects of the dermoepidermal junction). Two subtypes revealed specific features which could be assessed qualitatively: distinctive, circumscribed, clumped tonofilament bodies were present in basal keratinocytes from epidermolysis bullosa herpetiformis Dowling-Meara and thick (30 nm diameter) cross-striated anchoring fibrils were absent in epidermolysis bullosa dystrophica generalisata gravis. Epidermolysis bullosa simplex Köbner and Weber-Cockayne forms could not be distinguished.     

Dynamic ultrastructural changes of the connective tissue sheath of human hair follicles during hair cycle

Summary Ultrastructural changes of the connective tissue sheath (CTS), including the hyaline membrane, of human hair follicles during the hair cycle, were studied in normal scalp skin specimens. In early anagen, the CTS was composed of a thin basal lamina and surrounding collagen tissue. The collagen tissue gradually thickened during the development of the hair and hair follicle. In mature anagen hair follicles, the collagen tissue was separated into three layers. The inner collagen layer, just outside the basal lamina, was thin and composed of collagen fibres running longitudinally parallel to the hair axis. The middle collagen layer was very thick with its collagen fibres running transversely against the hair axis and surrounding the inner hair tissue. Many fibroblasts were present among the collagen fibres in the middle layer, whereas the inner layer contained almost none. In the outer collagen layer, collagen fibres ran in various directions parallel to the outer surface of the outer root sheath cells. In late anagen, the basal lamina became very thick. In catagen, the basal lamine and the inner collagen layer became corrugated and showed oedematous change and degeneration. Surrounding fibroblasts showed active production of new collagen fibres, which seemed to fill the spaces left by the retraction of the hair follicle and hyaline membrane. These ultrastructural changes of the CTS show that there may be dynamic metabolic changes of the connective tissue around human hair follicles during the hair cycle.     

A comparative study between electron microscopy and immunofluorescence mapping in the diagnosis of epidermolysis bullosa

INTRODUCTION: The classification of epidermolysis bullosa (EB) into 3 main subtypes has been based on electron microscopy (EM) that is able to directly visualize and quantify specific ultrastructural features. Immunofluorescence antigenic mapping (IFM) is a technique that determines the precise level of skin cleavage by determining the site of binding of a series of antibodies. To date, no study has compared the accuracy of these two techniques in diagnosing the major types of EB.
METHODS: A prospective cohort of 33 patients thought to have EB on clinical grounds had both EM and IFM. The sensitivity and specificity of EM and IFM were calculated using the genetic results as the 'gold standard'. Statistical analysis involved the determination of positive and negative predictive values, accuracies, positive and negative likelihood ratios and post-test probabilities of the IFM and EM diagnosis being correct compared to genetic diagnosis.
RESULTS: 30/33 cases had a positive EB diagnosis. TEM subclassified EB into its three major forms in 24/30 cases (80%) and IFM in 29/30 cases (97%). Overall, TEM sensitivities and specificities when compared to genetic results were 71% and 81%, respectively. IFM sensitivities and specificities when compared to genetic results were 97% and 100% respectively. If a patient tested positive for EB by IFM, the likelihood ratio of having a particular type of EB was consistently greater than 20 against the reference standard (compared to a likelihood ratio less than 10 for TEM).
CONCLUSION: These findings dispute the contention that EM and IFM are equally accurate and sensitive as diagnostic tests for the classification of the major types of EB. The results indicate that the diagnosis of EB is improved (sometimes substantially) by the use of IFM compared to TEM.     

性生活质量与家庭关系、幸福感的关系研究

目的:为探索个体的性生活质量与家庭关系、幸福感之间存在的关系及对幸福感的影响。方法:以广州市为例,采用分层随机抽样的方法,对3477名广州居民进行了性生活质量、家庭关系与幸福感指数的问卷调查。结果:调查对象对性生活的评价普遍较好,40.6%仍存在性生活困难的烦恼。与伴侣同住者的性生活质量较好,影响其幸福感的因素分别是家庭支持、性需求满足程度、我爱家人、家人关系、性生活满意度以及家庭摩擦;影响不同住者的幸福感因素分别是家庭支持、对性生活的评价、家人关系、性生活烦恼程度、爱家人及性生活满意度;两组存在差异。结论:提高个体的幸福感水平途径之一在于建立良好的家庭关系,离婚人群尤其需要家人的关注。     

A comparative study between transmission electron microscopy and immunofluorescence mapping in the diagnosis of epidermolysis bullosa

The classification of epidermolysis bullosa (EB) into 3 main subtypes has been based on transmission electron microscopy (TEM) that is able to directly visualize and quantify specific ultrastructural features. Immunofluorescence antigenic mapping (IFM) is a technique that determines the precise level of skin cleavage by determining binding sites for a series of antibodies. To date, no study has compared the accuracy of these two techniques in diagnosing the major types of EB. A prospective cohort of 33 patients thought to have EB on clinical grounds had TEM, IFM, and genetic testing performed. The sensitivities and specificities of TEM and IFM were calculated compared with the genetic results. Of 33 cases, 30 had a positive EB diagnosis. TEM subclassified EB into its three major forms in 24/30 cases (80%) and IFM in 29/30 cases (97%). Overall, TEM sensitivities and specificities when compared with genetic results were 71% and 81%, respectively. IFM sensitivities and specificities when compared with genetic results were 97% and 100%, respectively. If a patient tested positive for EB by IFM, the likelihood ratio of having a particular type of EB was consistently greater than 20 against the reference standard (compared with a likelihood ratio less than 10 for TEM). Our results indicate that the diagnosis of EB is improved (sometimes substantially) by the use of IFM compared with TEM.     

Progressive changes in cuticular pattern along the shafts of human hair as seen by scanning electron microscopy

Summary.— A study of normal hair shafts by scanning electron microscopy shows that there is a regular and progressive loss of the normal cuticular scale pattern from root to tip. Appearances found in pathological conditions should be interpreted in the light of this normal variation.     

疣状瓶霉致皮肤着色真菌病一例及致病菌的辅酶Q和DNA序列测定

目的报告1例疣状瓶霉致皮肤着色真菌病,并探讨其致病菌的实验室特征。方法皮损组织病理学检查、真菌学检查,分离株辅酶Q检测、DNA序列鉴定。结果该病表现为慢性疣状增殖性斑块,病程长,外伤后易发病。真皮层可见棕色厚壁孢子。菌落生长缓慢,需观察4周。小培养沙氏琼脂培养基无特殊结构,马铃薯葡萄糖琼脂见瓶梗多生长于短侧枝或气生菌丝顶端,玉米粉琼脂Ⅰ见瓶梗多侧生于菌丝,后两者其他结构相同。辅酶Q系统检测及LSUrDNA D1/D2区域碱基序列测定,与标准菌株比较完全相同。结论我国该病较少见,确诊需作真菌培养及组织病理,应同时采用沙氏琼脂培养基、马铃薯葡萄糖琼脂、玉米粉琼脂Ⅰ3种培养基培养。辅酶Q检测及分子生物学鉴定可排除表型不同的干扰,有利于进一步鉴定菌种。     

Relationship between the echogenicity of subcutaneous tissue and the depth of forehead wrinkles

Background/purpose: Subcutaneous tissue is rarely studied in research on wrinkles. We used diagnostic ultrasonography to produce images of subcutaneous tissue of the forehead, one of the areas where age‐related wrinkles form. We quantified the resulting echogenicity and investigated its relationship with wrinkle depth. Methods: One hundred and seventy‐three Japanese subjects were divided into four age groups (21–28 years, 35–41 years, 47–59 years, 65–75 years). Maximum wrinkle depth (R_max) was measured in the forehead. On an ultrasound image, which was captured by scanning perpendicular to the deepest wrinkle, we set a 12.5‐mm‐wide region of interest by aligning the deepest point of the wrinkle at its center and then obtained the ratio of the area exceeding this threshold to the total area as the echogenicity. Results: R _max increased and the echogenicity decreased with age. A negative correlation was found in the oldest group but was not found in other groups, presumably due to individual differences in the echogenicity among younger subjects. Conclusion: This study suggests that the internal structure of subcutaneous tissue, as observed by ultrasonography, is related to wrinkle depth. The relationship between wrinkle depth and echogenicity of subcutaneous tissue is particularly pronounced in the elderly.     

Scanning electron microscopy of Neisseria gonorrhoeae. Age-induced changes in macro- and microstructure of virulent and avirulent colonies.

Virulent and avirulent gonococcal colonies were studied in the scanning electron microscope. Cells in virulent, in contrast to avirulent, colonies were found to be connected by numerous strands. After longer incubation periods, type 2 colonies segregated out regions of cells virtually lacking these strands. Cells within these areas probably represent avirulent segregants. The microstructure of individual colonies revealed no topographical differences. In certain colonies large smooth spherical cells were seen, probably representing wall-deficient gonococcal variants.     

Relationship between the echogenicity of subcutaneous tissue and the depth of eye corner wrinkles

Background/purpose: A close relationship was found between the internal structure of subcutaneous tissue and wrinkle depth in our previous study of human forehead. The present study examined the relationship in the eye corner. Methods: One hundred and seventy‐three Japanese subjects were divided into four age groups (21–28 years, 35–41 years, 47–59 years and 65–75 years). The maximum wrinkle depth (R_max) of an eye corner wrinkle was obtained. On an ultrasound image, which was captured by scanning perpendicular to the wrinkle, we set a 12.5‐mm‐wide region of interest (ROI) by aligning the deepest point of the wrinkle at its center and then obtained the ratio of the area exceeding an echogenicity threshold to the total area as the echogenicity. Results: No correlation was found between the R_max and echogenicity. The relationship was further analyzed by dividing the ROI into two: one above and the other below the deepest point of the wrinkle. A negative correlation was detected in the lower ROI of the oldest group. The difference in echogenicity between the upper and the lower ROIs of the oldest group showed a positive correlation with the R_max. Conclusion: These results suggest that the subcutaneous tissue structure is related to wrinkle depth.     

Scanning electron microscopy of the normal epidermis and the epidermis in vitro

A simplified technique has been used to examine the epidermis in five skin biopsies and in eight cultured skin specimens by scanning electron microscopy. Paraffin or cryostat sections of the tissue were cut and prepared according to routine histological methods and then given an electrically conducting coating before examination in the scanning electron microscope. The epidermis was easily identified and a particularly good view was obtained of intercellular bridges at high magnifications. Intra-epidermal and basal layer dendritic cells were also easily located and their relationships to surrounding keratinocytes by long intercellular processes are described. The scanning electron microscopic appearance of epidermal cells in cultured explains of skin showed a strong resemblance to other cells and tissues in culture and also demonstrated the presence of a unicellular or subcellular membrane at the leading edge similar in appearance to the undulating membrane of fibroblasts in culture. It is stressed that the method is of particular use in the examination of intercellular relationships within the epidermis and in the inspection of histological material at higher magnifications than are possible by light microscopy.     

Relationship between intensities of skin test reactions to glass-fibres and chemical irritants

A total of 98 workers at a glass-wool factory were patch tested with glass-fibres and six chemical irritants. A rubbing test with the fibres, a Trafuril test and provocation of dermographism were also performed. The subjects with strong patch test reactions to one quality of fibres also reacted strongly to the other types of fibres but did not show an increased sensitivity to other tests. The subjects with intense skin reactions to rubbing with the fibres showed an increased skin reactivity to Trafuril. A tendency towards increased reactivity to the patch tests with fibres was found in persons with fair skin and blue eyes.