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[Glucose-6-phosphate dehydrogenase (G6PD) deficiency--a cause of anaemia in pregnant women].

Glucose-6-phosphate dehydrogenase (G6PD) is one of the most important cytoprotective enzymes for oxidative stress. The WHO classification of G6PD deficiency, based on enzyme activity and clinical significance, distinguishes five variants. Chronic haemolytic process is rare and the main factors causing haemolysis are: infections, substances derived from plants, drugs with high oxidation-reduction potential, stress, ketoacidosis in diabetes and surgery operations. We report two cases of women belonging to the class 3 of the WHO classification in whom haemolysis occured during pregnancy. One of the patients developed two incidents of haemolytic anaemia. The cause of the first episode, nine months before pregnancy, was probably infection of the urinary tract caused by Escherichia coli, but the influence of the drugs also cannot be excluded. Because of the genetic background of this enzymopathy we also examined members of the patients, families but did not find any evidence of G6PD deficiency among them. The reported cases indicate that haemolytic anaemia caused by G6PD deficiency may occur during pregnancy what can lead to many not only haematological but also serious obstetrical complications such as infertility, fetus malformations and even its death. We also draw attention to several difficulties in diagnosing G6PD deficiency especially during haemolysis.

Adult↗

Masked giant-cell arteritis.

Five bipsy-proven cases of giant-cell arteritis illustrate some of the lesser known, but not uncommon, masquerades of this disease. The delay in reaching the diagnosis, which is common with these presentations, was a major factor in the emergence of serious sequelae including arotic regurgitation, stroke, and death. To increase awareness of the variety of clinical presentation of giant-cell arteritis, a classification of these variants into cachectic, febrile, and other forms is suggested.

Aged↗

Mutation analysis and molecular genetics of epidermolysis bullosa.

Cutaneous basement membrane zone (BMZ) consists of a number of attachment structures that are critical for stable association of the epidermis to the underlying dermis. These include hemidesmosomes, anchoring filaments and anchoring fibrils which form an interconnecting network extending from the intracellular milieu of basal keratinocytes across the dermal-epidermal basement membrane to the underlying dermis. Aberrations in this network structure, e.g. due to genetic lesions in the corresponding genes, can result in fragility of the skin at the level of the cutaneous BMZ. The prototype of such diseases is epidermolysis bullosa (EB), a heterogeneous group of genodermatoses characterized by fragility and blistering of the skin, often associated with extracutaneous manifestations, and inherited either in an autosomal dominant or autosomal recessive manner. Based on constellations of the phenotypic manifestations, severity of the disease, and the level of tissue separation within the cutaneous BMZ, EB has been divided into clinically distinct subcategories, including the simplex, hemidesmosomal, junctional and dystrophic variants. Elucidation of BMZ gene/protein systems and development of mutation detection strategies have allowed identification of mutations in 10 different BMZ genes which can explain the clinical heterogeneity of EB. These include mutations in the type VII collagen gene (COL7A1) in the dystrophic (severely scarring) forms of EB; mutations in the laminin 5 genes (LAMA3, LAMB3 and LAMC2) in a lethal (Herlitz) variant of junctional EB; aberrations in the type XVII collagen gene (COL17A1) in non-lethal forms of junctional EB; mutations in the alpha6 and beta4 integrin genes in a distinct hemidesmosomal variant of EB with congenital pyloric atresia; and mutations in the plectin gene (PLEC1) in a form of EB associated with late-onset muscular dystrophy. Identification of mutations in these gene/protein systems attests to their critical importance in the overall stability of the cutaneous BMZ. Furthermore, elucidation of mutations in different variants of EB has direct clinical applications in terms of refined classification, improved genetic counseling, and development of DNA-based prenatal testing in families with EB.

Basement Membrane↗

Cluster headache.

In this article we describe the clinical features, natural history, and clinical variants of cluster headaches, following the modern International Headache Society classification of cluster headaches in its two types: episodic and chronic. The basic pathophysiology is considered to be the trigeminal vascular system, the common final pain pathway, with pain initiated in a cyclical fashion by disordered central hypothalamic pacemaker. Oxygen, rapidly acting ergotamine, or dihydroergotamine preparations serve as abortive treatment of acute attacks; various pharmacotherapeutic options and combination therapies aid in the prophylaxis of cluster headache; and trigeminal radio frequency gangliorhizolysis is a very useful surgical approach in patients with chronic cluster headache who are resistant to medical treatment.

Cluster Headache↗

[Classification of psychopathies].

The author proposes a new "ring-like" classification of psychopathies which includes the most definitely described prevalent clinical variants with due consideration of mutual transitions of some forms of psychopathy into others (mixed forms, "complex" psychopathic syndrome) and also an energy potential of individuals with some persons being referred to the sthenic (excitable) pole and others to the asthenic (inhibitory) pole. The main disorder obligate to all psychopathic personalities is mental infantilism whereas the inadequacy of emotional manifestations and alterations in the sphere of thinking are considered as secondary manifestations determining one or another clinical variant of psychopathy and are related to congenital mental activity of a given individual.

Brain Diseases↗

The dysplastic nevus. Clinical and pathologic features.

The dysplastic nevus has not only been considered to be a "marker," but also a formal "precursor" of malignant melanoma. Therefore, these lesions are important to recognize clinically. This article presents a classification of the dysplastic nevus based upon its variable clinical presentations. It is hoped that this classification will assist the physician to recognize many of the clinical variants of this unusual melanocytic nevus and, thus, to identify patients at greater risk for the development of malignant melanoma.

Biopsy↗

The ClinGen Severe Combined Immunodeficiency Disease Variant Curation Expert Panel: Specifications for classification of variants in ADA, DCLRE1C, IL2RG, IL7R, JAK3, RAG1, and RAG2.

PURPOSE: This collaborative study, led by the Clinical Genome Resource Severe Combined Immunodeficiency Disease Variant Curation Expert Panel (ClinGen SCID-VCEP), implemented and adapted the American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) guidelines for interpreting germline variants in genes with established relationships to SCID. The effort focused on the 7 most common SCID-related genes identified by SCID newborn screening in North America: ADA, DCLRE1C, IL2RG, IL7R, JAK3, RAG1, and RAG2. METHODS: The SCID-VCEP conducted a rigorous review of variants that involved database analyses, literature review, and expert feedback to derive gene-specific modifications to the ACMG/AMP guidelines. These specifications were validated using a pilot set of 90 variants. RESULTS: Of these 90 variants, 25 were classified as pathogenic, 21 as likely pathogenic, 14 as variants of uncertain significance, 18 as likely benign, and 12 as benign. Seventeen variants with conflicting classifications in ClinVar were successfully resolved. The criteria included modifications to 20 of the 28 original ACMG/AMP criteria specific to SCID-related genes. CONCLUSION: The SCID-specific variant curation guidelines developed by the SCID-VCEP will enhance the precision of SCID genetic diagnosis and provide a robust framework for interpreting variants in SCID-related genes, contributing to appropriate treatment of SCID.

Humans↗

Secretory meningioma: clinical, histologic, and immunohistochemical findings in 31 cases.

BACKGROUND: Secretory meningioma is a rare histologic variant characterized by a unique epithelial differentiation of meningothelial cells resulting in the production of hyaline inclusions. Most previous reports have presented single case observations. The authors selected 31 cases for a clinicopathologic study to characterize this type of tumor further. METHODS: Clinical data were compiled and the extent of peritumoral edema was assessed from preoperative computed tomography or magnetic resonance imaging scans. Preparations of surgical specimens of all tumors were studied after both conventional histologic and immunohistochemical preparations were made. Immunostaining was performed by either the avidin-biotin complex method or the alkaline phosphatase-antialkaline phosphatase method using 22 primary antibodies. RESULTS: In the tumor collection used in this study, secretory meningiomas represented 3% of meningiomas. The female-to-male ratio was 9:1. Most tumors were located at the sphenoid ridge or at the frontal convexity, and recurrences were not observed. Eighty-four percent of tumors presented with slight to marked peritumoral edema. The MIB-1 staining index showed a mean of 3.8%. Inclusions and surrounding cells consistently expressed epithelial membrane antigen, cytokeratins, carcinoembryonic antigen, and carbohydrate antigen 19-9. In decreasing frequency, they also contained alpha1-antitrypsin, immunoglobulin (Ig)A, alpha1-antichymotrypsin, IgM, and IgG. Cells positive for vimentin and S-100 did not contain inclusions. All tumors were positive for progesterone receptors. Macrophages were stained with antibodies to factor XIIIa, human leukocyte antigen-DR, and alpha1-antitrypsin. In 64% of cases, tumor vessels lacked expression of glucose transporter protein 1. CONCLUSIONS: The classification of secretory meningioma as a distinct variant has been justified on clinical, histologic, and immunohistochemical grounds. The unique epithelial features call attention to the broad spectrum of differentiation properties found in meningiomas.

Adult↗

Molecular Landscape and Advanced Diagnostic Technologies for BRAF Mutations in Cancer: From Quantitative PCR and ddPCR to CRISPR-Based Platforms.

BRAF mutations are key oncogenic alterations across multiple malignancies, including melanoma, thyroid carcinoma, colorectal cancer, non-small cell lung cancer, glioma, and hairy cell leukemia. The most prevalent variant, BRAF-V600E, induces constitutive activation of the MAPK signaling pathway, promoting tumor progression and influencing therapeutic responsiveness. Accurate detection of BRAF alterations is therefore essential for molecular classification, prognostic assessment, treatment selection, and resistance surveillance. This review summarizes the molecular heterogeneity of BRAF mutations and critically evaluates current diagnostic methodologies. Conventional approaches such as allele-specific PCR and Sanger sequencing are compared with advanced quantitative platforms, including high-resolution melting analysis, droplet digital PCR, and next-generation sequencing, with emphasis on analytical sensitivity, mutation coverage, and clinical applicability. Emerging technologies such as CRISPR-based assays, rolling circle amplification systems, and nanoparticle-based biosensors and point-of-care diagnostic platforms are also discussed for their potential to enhance ultra-sensitive detection, particularly in liquid biopsy settings. These emerging tools are highlighted for their potential to enable ultra-sensitive, rapid, and decentralized mutation detection, particularly in liquid biopsy settings. Key challenges, including intratumoral heterogeneity, low allele-frequency variants, FFPE-associated artifacts, and clonal evolution under therapeutic pressure, are examined within a translational framework. In addition, we examine critical barriers to clinical implementation, including standardization, cost, and global accessibility of molecular diagnostics, and outline potential solutions through scalable technologies and decentralized testing strategies. We propose that optimal BRAF testing requires a mutation subclass-informed and clinically integrated strategy combining comprehensive baseline profiling with longitudinal molecular monitoring. Future diagnostic paradigms will likely integrate multi-omics data and artificial intelligence (AI)-assisted interpretation to refine precision oncology implementation. Looking forward, we propose that optimal BRAF testing will require integration of multi-omics profiling with AI-assisted interpretation, enabling automated variant classification, real-time clinical decision support, and improved prediction of therapeutic response and resistance.

Humans↗

[Psoriasis pustulosa generalisata--classification, clinical aspects and therapy. Review and experiences with 18 patients].

On the basis of clinico-morphological criteria we suggest the following classification of various pustular forms of psoriasis into four subtypes: generalized pustular psoriasis (von Zumbusch) and its atypical forms, erythema anulare centrifugum-like psoriasis with and without pustulation (EACP); psoriasis vulgaris with pustulation; palmo-plantar pustular psoriasis (Königsbeck-Barber) and its acral variant; acrodermatitis continua suppurativa (Hallopeau), and transitional forms. This classification takes into consideration both clinical aspects and response to treatment, and allows a prognosis of the various types of pustular psoriasis. Owing to its mild course and good treatment results, EACP represents a special form of psoriasis pustulosa generalisata. In our group of patients, systemic glucocorticosteroid therapy has proved deleterious, whereas oral photochemotherapy and etretinate have been found to be highly effective modes of therapy with only mild side effects and have been able to induce even permanent remission in EACP.

Adult↗

Testicular sertoli cell tumours and relative sub-types. Analysis of clinical and prognostic features.

INTRODUCTION: Sertoli cell tumours have a rare (0.4-1.5% of all testicular neoplasms) and heterogeneous pathology. The aim of this paper is to analyse the histological classification of Sertoli cell tumours, in order to assess if the three different histotypes--classic type, large cell calcifying Sertoli cell tumour (LCCSCT) and sclerosing Sertoli cell tumour (SSCT)--really present distinctive clinical and prognostic features. MATERIALS AND METHODS: The current literature was reviewed; Sertoli cell tumour clinical series and single case reports were searched and analysed. Hence, more than 200 classic Sertoli cell tumours, 48 LCCSCTs and only 12 SSCTs were found. The thirteenth SSCT has been found by us in a 34-year-old man. RESULTS: Every single sub-type presents clinical specific characteristics regarding age of onset, bilaterality, focality, abnormal hormone production, correlated systemic symptoms. Ultrasonographic findings, size and--above all--malignant potential. CONCLUSIONS: The precise classification of these tumours is not important only histologically: the currently recognised variants really differ in clinical presentation and course. Moreover, LCCSCTs can be further divided in two subgroups with very different clinical behaviour, those in older patients and those associated with well-known syndromes. These clinical and prognostic variables are of great importance when deciding on the therapeutical approach.

Adult↗

Spinocerebellar degeneration.

Forty cases with several forms of spinocerebellar degenerations were studied. The diagnosis was based on an appropriate clinical picture, radiological investigation and family history. There are multiple variants of spinocerebellar degeneration and classification of these diseases remains unsatisfactory and therefore controversial. We classified cases into three main groups. The numbers of cases in each of these groups were as follows: cerebellar group = 16 cases, cerebellar plus group = 9 cases, spinal group = 15 cases. The age, age of onset, mode of inheritance, clinical pictures and cerebrospinal fluid analysis of these cases were discussed. Results of various radiological investigations of these cases were reviewed. From our observations we can conclude that the morphologic changes seen in radiological investigations in our cases were more varied than the observed clinical syndromes. The cause of these syndromes remains unknown and there is no established treatment for spinocerebellar degeneration. We can only offer symptomatic treatment, physiotherapy and genetic counselling for this group of patients.

Adult↗

New developments in the pathology of skull base tumors.

As an anatomical interface between various tissues, the skull base harbors an exceptionally broad variety of neoplasms, some of which pose a major challenge for surgical pathology. The characterization of distinct immunohistochemical expression profiles and the identification of molecular genetic alterations associated with different tumor entities have significantly advanced this field. The new World Health Organization (WHO) classification of tumors of the nervous system lists 15 histopathological variants of meningioma. Of clinical importance are those entities that carry an increased risk of recurrence and a poor prognosis, i.e., the atypical meningioma (WHO grade II), clear-cell meningioma (WHO grade II), chordoid meningioma (WHO grade II), rhabdoid meningioma (WHO grade III), papillary meningioma (WHO grade III), and anaplastic meningioma (WHO grade III). Diagnostic criteria for atypical and anaplastic meningioma variants have now been stringently defined. The differential diagnosis of meningiomas includes hemangiopericytoma, hemangioblastoma, solitary fibrous tumor, sarcomas, and chordoid neoplasms. Recent data highlight the importance of distinguishing chordoma and chondrosarcoma of the skull base since chondrosarcomas show a significantly better clinical outcome. Among the less common, aggressive tumor entities in this anatomical region, infiltrating pituitary adenoma/pituitary carcinoma, superficial malignant gliomas, rhabdomyosarcoma, olfactory neuroblastoma, various sarcomas, and malignant lymphoma must be considered. Profiles of molecular genetic alterations have been established for several of these neoplasms and may facilitate the differential diagnosis. This review summarizes recent developments in the histopathological characterization, classification, and molecular pathology of neoplasms arising at the skull base.

Biomarkers, Tumor↗

[Clinical and pathological characteristics of focal segmental glomerulosclerosis in children].

OBJECTIVE: To investigate the clinical and pathological characteristics of focal segmental glomerulosclerosis (FSGS) in children. METHODS: The data of 38 children,aged from one and half to 15 years, 25 boys and 13 girls, with primary FSGS were studied retrospectively. RESULTS: Majority of the cases in this study were school-aged children. The average age of initial onset was 8.9 +/- 3.68 years. The ratio of boys to girls was 1.92. The clinical manifestation included isolated proteinuria in 3 cases, proteinuria and hematuria in 1 and nephrotic syndrome in 34 (simple type in 16 and nephritic type in 18). Of 38 cases, 24 (63%) presented with hematuria, 11 (29%) with hypertension and 7 (18%) with decreased creatinine clearance. The pathologic classification included perihilar variant in 17 cases, peripheral variant in 14 and tip variant in 7. The predominant clinical feature of children with tip variant was simple type of nephrotic syndrome (86%). Microscopic hematuria was not common (29%). Blood pressure and renal function were normal. The children with diffuse mesangial hypercellularity superimposed on changes of FSGS (in 21 of 38 cases) were more likely to have hematuria (76%) and less simple nephrotic syndrome (30%). The initial treatment response to prednisone in 34 cases with nephrotic syndrome showed sensitive in 12 cases, resistant in 21 and unknown in 1. Transition from sensitive to resistant occurred in six of 12 children. Three of 4 cases with non-nephrotic syndrome showed no response and the remaining one had unknown response. It was found that 44% of children who received cyclophosphamide and 83% of children who received pulse methylprednisolone and pulse cyclophosphamide or cyclosporin A in addition to oral steroids had complete or partial remission. Correlation analysis showed that the level of proteinuria after treatment was correlated directly with renal tubulointerstitial lesion and renal function (Pr = 0.48, P < 0.05; Pr = 0.45, P < 0.05). CONCLUSION: FSGS was common in school-aged children. The predominant presenting feature was nephrotic syndrome. Hematuria was common. Hypertension and renal insufficiency were less frequently seen. The renal biopsy showed multiple variants. Pulse methylprednisolone and pulse cyclophosphamide or cyclosporin A treatments showed relatively good response.

Adolescent↗

[Mediastinal large B-cell lymphoma].

Mediastinal B-cell lymphoma is a locally highly aggressive tumour which was first described in the early 1980s. The incidence is about 2-3% of all non-Hodgkin's lymphomas. The conceptional evolution of this lymphoma entity was hampered by its low incidence and the broad spectrum of morphological variants present. However, since mediastinal B-cell lymphoma has distinct morphological, immunological, genetic, and clinical features, it has been listed in the revised European-American Classification of Lymphoid Neoplasms (REAL-Classification) since 1994 as a variant of diffuse large B-cell lymphoma. In the World Health Organization classification of malignant lymphomas, mediastinal B-cell lymphoma is now listed with an own disease code (ICD-9679/3).

Humans↗

Clinical and pathologic characteristics of focal segmental glomerulosclerosis pathologic variants.

Histologic variants of idiopathic focal segmental glomerulosclerosis (FSGS) may have prognostic value. A recent working classification system has distinguished five FSGS variants. We evaluated a cohort of adult patients with biopsy-proven FSGS diagnosed between March 1982 and July 2001 to determine if subtypes were associated with renal outcome. Renal biopsies were reviewed by two pathologists. Demographic and clinical data were obtained from charts. Outcomes were partial and complete remission of the nephrotic syndrome, and renal failure. The frequency of FSGS variants was: 3% cellular (N=6), 11% collapsing (N=22), 17% tip lesion (N=34), 26% perihilar (N=52), and 42% not otherwise specified (NOS) (N=83). Collapsing FSGS affected younger and more often black patients. Black race was uncommon in tip variant. Collapsing and tip variants had higher proteinuria and lower serum albumin than perihilar and NOS variants. Better renal function and less severe tubulointerstitial injury were observed in patients with tip variant. These patients were more likely to receive steroids and more often achieved complete remission (50%). After a median follow-up of 1.8 years, 23% of patients were on dialysis and 28% had renal failure. Collapsing FSGS had worse 1-year (74%) and 3-year (33%) renal survival compared to other variants (overall cohort renal survival at 1 and 3 years: 86 and 67%). Different histologic variants of FSGS have substantial differences in clinical features at the time of biopsy diagnosis and substantial differences in renal outcomes.

Adult↗

[Subdivision of certain morphological variants of chronic glomerulonephritis].

Modern methods allow to detail morphological classification of chronic glomerulonephritis, to adapt it to the clinical classification and to recommend it for practical use. This specification concerns minimal changes and a group of mesangial chronic glomerulonephritis. The term "minimal changes" is a light-microscopic definition and covers rather a heterogeneous group of diseases or their initial manifestations. Differential diagnosis of these diseases is feasible only at the electron microscopic level. A group of chronic glomerulonephritis (mesangioproliferative and mesangiocapillary) includes variants distinguished on the basis of immunohistochemical, light microscopic and electron microscopic methods. Of them, the immunohistochemical method is most valuable for differentiation of mesangioproliferative glomerulonephritis.

Chronic Disease↗