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PubMed2004

Eosinophilic dysplasia of the cervix: a newly recognized variant of cervical squamous intraepithelial neoplasia.

A proportion of cervical squamous intraepithelial lesions encountered in surgical pathology practice contain both metaplastic features and some degree of atypia [so-called eosinophilic dysplasia (ED)] that defy classification according to established criteria. To elucidate the nature of these lesions, we compared 44 cases of ED to 20 classic high-grade squamous intraepithelial lesions (HSILs) and 10 squamous metaplasias using a panel of biomarkers and human papillomavirus (HPV) testing. EDs were defined as 1) lack of normal maturation; 2) relatively abundant eosinophilic cytoplasm and distinct cell borders compared with conventional HSIL; 3) mildly to moderately increased nuclear to cytoplasmic ratio; and 4) focal dysplastic nuclei showing nuclear enlargement, hyperchromasia, variable nuclear membrane irregularities, and appreciable nucleoli. Expression of p16 (p16), MIB-1 (Ki-67) labeling index, and HPV DNA detection and typing were performed on each case. The majority of EDs showed more than three atypical cells in an entire lesion but lack of apparent features of HSIL. It was common to find neighboring cervical squamous metaplasia and/or conventional SILs (either HSIL or low-grade squamous intraepithelial lesion [LSIL]). Among the 44 cases, 18 (45%) ED lesions were found to be associated with HSIL, 15 (34%) with LSIL or condylomatous lesions, and 13 (30%) EDs were seen without any SILs in the entire specimens. Area of benign squamous metaplasia was found in all ED cases. High levels of p16 and MIB-1 expression were seen in 41 (93%) of 44 ED cases with degrees of immunoreactivity closely resembling those seen with HSIL. Of 16 EDs tested, 13 (81%) were positive for HPV DNAs. Among 10 HPV-positive cases subtyped, 9 (90%) cases contained intermediate- and/or high-risk HPVs and 1 case contained a novel HPV. In the follow-up of pure ED cases, the majority showed presence of dysplastic lesions of either HSIL or LSIL on either loop electric excision procedures or Papanicolaou test samples after a 6- to 10-week period. Therefore, ED represents an unrecognized and potentially clinically significant subgroup of cervical intraepithelial lesions. Based on the unique histologic appearance of ED, its association in some cases with HSIL, the overall immunohistochemical findings, frequent association of ED with intermediate- and/or high-risk HPV infection, and limited follow-up data, we believe that ED represents a variant of HSIL (CIN 2). Since ED possesses histologic features of both dysplasia and metaplasia, we speculate that it may arise from metaplastic cervical squamous epithelium that has subsequently become infected with intermediate- or high-risk HPV.

Adolescent↗
PubMed1989

Schwannomatosis. An unusual variant of neurofibromatosis or a distinct clinical entity?

Multiple schwannomas have frequently been seen in patients with neurofibromatosis. Recently, the association of multiple cutaneous schwannomas, central nervous system tumors, and various neurologic deficits has been described in Japanese patients as a condition called schwannomatosis. We describe the first non-Japanese cases of schwannomatosis and compare and contrast this unusual condition with the well-known variants of neurofibromatosis. We conclude that the features of schwannomatosis are distinct and define a condition that does not fit into the current classification scheme of neurofibromatosis. The occurrence of multiple cutaneous schwannomas in the absence of cardinal features of neurofibromatosis may indicate the presence of central nervous system tumors or various neurologic deficits.

Adolescent↗
PubMed2006

[Cutaneous lupus erythematosus. Part 1: clinical manifestations and classification].

Cutaneous lupus erythematosus (CLE) is a heterogenous disorder with a wide range of skin manifestations. Therefore, it has been difficult to develop a unifying concept for classifying CLE from the dermatologic perspective in the past. In 2004, the classification system was updated and includes now acute CLE (ACLE), subacute CLE (SCLE), chronic CLE (CCLE), and intermittent CLE (ICLE). Additional rarely described variants are not listed as separate entities but are included in the classical forms. Diagnosis of the different subtypes of CLE is made by considering genetic, clinical, histopathologic, and immunoserologic findings, with a systematic analysis of individual criteria. In the past years, the etiology and pathogenesis of CLE has been subject of intensive research and it has been shown by several groups that exogenous factors, such as ultraviolet light and drugs, can induce CLE. The first part of this review will enable the reader to identify the various clinical manifestations of CLE and to employ characteristic criteria to assess differential diagnostic considerations.

Biopsy↗
PubMed1997

[Adenoid cystic cribriform trichoblastoma].

In hair germ tumors, hair follicle development is partially or completely recapitulated. The trichoblastoma represents a purely epithelial tumour within this group of tumours. We identified a trichoblastoma showing exclusively adenocystic features in a 32 years old woman. This variant has been very rarely described in the literature. We review the history of hair germ tumors and discuss the problems of their classification.

Adult↗
PubMed2004

Congenital dyserythropoietic anemias: epidemiology, clinical significance, and progress in understanding their pathogenesis.

The congenital dyserythropoietic anemias (CDAs) comprise a group of rare hereditary disorders of erythropoiesis, characterized by ineffective erythropoiesis as the predominant mechanism of anemia and by distinct morphological abnormalities of the majority of erythroblasts in the bone marrow. The classification in three types as proposed in 1968 is still valid, but there is genetic heterogeneity within each type, and there are additional variants of unknown genetic basis. CDA II is the most frequent, and the nonfamilial type of CDA III the rarest group. The genes of CDA II and CDA III were mapped to chromosome 20 and 15, respectively, and the gene of CDA I on 15q was recently cloned. Therapeutic decision making requires definition of the type, an estimate of individual severity, and presence of or risk for complications. Therapeutic measures include interferon-alpha for CDA I, splenectomy for CDA II, and iron depletion for all individuals at risk for secondary hemochromatosis.

Anemia, Dyserythropoietic, Congenital↗
PubMed1985

Comparison of African trypanosomes of different antigenic phenotypes, subspecies and life cycle stages by two-dimensional gel electrophoresis.

High resolution two-dimensional polyacrylamide gel (2D gel) electrophoresis and autoradiography were used to analyze the protein gene products of African trypanosomes biosynthetically labelled with [35S]methionine. Using cloned populations of parasites it was found that: antigenically different bloodstream trypanosomes from the same serodeme differed only in their variant surface glycoproteins; Trypanosoma brucei, T.b. rhodesiense and T.b. gambiense subspecies could be distinguished on the basis of differences in expressed proteins; transformation from bloodstream trypomastigotes to procyclic epimastigote culture forms was accompanied by loss of variant surface glycoproteins and several other qualitative and quantitative changes in minor proteins. The results indicate that 2D gel analysis may allow improved classification of African trypanosomes (based on the observation of hundreds of protein markers) and may also provide a general technique for the identification of lifecycle stage specific markers.

Animals↗
PubMed2005

VEGA, the genome browser with a difference.

The Vertebrate Genome Annotation (Vega) database is a community resource for browsing manual annotation from a variety of vertebrate genomes of finished sequence (http://vega.sanger.ac.uk). Vega is different from other genome browsers as it has a standardised classification of genes which encompasses pseudogenes and non-coding transcripts. The data is manually curated, which is more accurate at identifying splice variants, pseudogenes poly(A) features, non-coding and complex gene structures and arrangements than current automated methods. The database also contains annotation from regions, not just whole genomes, and displays multiple species annotation (human, mouse, dog and zebrafish) for comparative analysis. Vega encourages community feedback that results in annotation updates and manual annotation of finished vertebrate sequence.

Animals↗
PubMed2002

The Big Eye in the 21st century: the role of electron microscopy in modern diagnostic neuropathology.

Electron microscopy (EM) remains a powerful and even essential tool in modern diagnostic neuropathology. tumors are still encountered that defy histological or immunohistochemical classification, and EM can often provide answers in these cases. Tumors of the CNS for which EM is useful include unusual or atypical variants of meningioma, ependymoma, and schwannoma; oligodendroglioma-like tumors composed of small "clear" cells; and small "blue cell" tumors of childhood. EM is of great value in identifying site of origin for metastatic adenocarcinomas of unknown origin-an under-recognized and under-utilized potential for this technique. EM is useful in the diagnosis of peripheral nerve sheath tumors and gastrointestinal autonomic nerve tumors. EM is also important in the evaluation of certain congenital, inherited and metabolic diseases-including ceroid lipofuscinoses, CADASIL syndrome, certain myopathies, and mitochondrial encephalomyopathies--and of certain toxic and drug-induced peripheral neuropathies. An important application of EM is its utility in initiating a workup of an atypical tumor or metabolic condition, for which clinical and histological clues point in no obvious direction. In these situations, EM may provide either an answer outright (including answers to questions not asked) or important clues that guide further workup and narrow the range of diagnostic possibilities.

Central Nervous System Diseases↗
PubMed1992

Papillary thyroid carcinoma in Kanazawa, Japan: prognostic significance of histological subtypes.

A retrospective analysis of 183 papillary thyroid carcinomas was made in order to assess the prognostic factors related to survival. The following factors were found to adversely affect the prognosis: trabecular subtype of papillary carcinoma, the extent of the primary tumour, regional lymph node involvement, the presence of distant metastases, old age, male sex and the extent of the neck dissection. The presence of the follicular variant of papillary carcinoma and the extent of the thyroidectomy did not influence the prognosis. The trabecular subtype of papillary carcinoma is characterized by a trabecular or solid arrangement of follicular cells with nuclei of ground-glass appearance. Univariate and multivariate analysis indicated that patients with this type of thyroid tumour had a poorer prognosis than those with the well-differentiated or follicular variants of papillary carcinoma. In our opinion the trabecular subtype of papillary carcinoma should be included as a separate entity in the WHO classification of thyroid tumours.

Adolescent↗
PubMed2002

Relationship between Helicobacter pylori babA2 status with gastric epithelial cell turnover and premalignant gastric lesions.

BACKGROUND: Helicobacter pylori blood group antigen binding adhesin (BabA) mediates bacterial adherence to human blood group antigens on gastric epithelium. Although strains harbouring babA2 were recently found to be associated with peptic ulcer and gastric cancer, the role of babA2 in cellular turnover, severity of gastritis, and premalignant changes is poorly understood. AIM: We correlated H pylori babA2, vacuolating toxin (vacA), and cytotoxin associated gene A (cagA) genotypes with the severity of gastric inflammation and epithelial cell turnover in a group of Chinese patients from an area with a high incidence of gastric cancer. PATIENTS AND METHODS: H pylori isolates were obtained from 104 Chinese patients who participated in a gastric cancer prevention programme. Genotype variants of babA2, vacA, and cagA were determined by polymerase chain reaction. Antrum and corpus histopathology was examined according to the updated Sydney classification. Apoptosis was scored by terminal uridine deoxynucleotidyl nick end labeling (TUNEL) and proliferation by Ki-67 immunostaining. RESULTS: Of the 104 patients, 102 (98.1%) harboured cagA(+) strains and all had vacA s1 genotype. The babA2(+) strains were found in 83 (79.8%) patients and were associated with higher lymphocytic infiltration (p=0.028), presence of glandular atrophy (odds ratio (OR) 7.5, 95% confidence interval (CI) 2.3-24.3), and intestinal metaplasia (OR 7.4, 95% CI 2.2-25.3) in the antrum. Increased epithelial proliferation was also noted in individuals infected with babA2(+) strains (p=0.025). Strains harbouring cagA(+)/vacA s1 genotypes lacked this association in the absence of babA2. CONCLUSIONS: The presence of babA2(+) H pylori strains alone or in combination with cagA(+) and vacA s1 was associated with the presence of preneoplastic gastric lesions.

Adhesins, Bacterial↗
PubMed1975

Validity of a screening test for typing serum cholinesterase variants among Greek populations.

A screening method for determining the abnormal phenotypes of human serum cholinesterase variants in a population survey was investigated. The test appeared to be satisfactory in detecting abnormal genotypes, but not assigning them into correct classification. The results of the population survey indicate that there may be a higher frequency of ChU1ChD1 genotype than those reported earlier. Family studies of the suxamethonium-sensitive propositi in this population demonstrate that abnormal genes ChD1, ChF1 and ChS1 are segregating, according to the usual Mendelian type of inheritance pattern. The possibility of a relatively high frequency of these abnormal genotypes among the Greek population has been indicated.

Cholinesterases↗
PubMed2003

An undescribed first branchial cleft anomaly.

A variant of a type 2 first branchial cleft anomaly, in which accessory ossicles were found, is described. There follows a discussion of the classification of first branchial cleft abnormalities and how this particular case falls outside the standard classification. CT scanning is mentioned as the investigation that is most useful for defining these abnormalities.

Branchial Region↗
PubMed1996

The variant forms of autoimmune hepatitis.

OBJECTIVES: To review the diagnostic criteria for autoimmune hepatitis, to characterize the variant forms of autoimmune hepatitis, and to indicate appropriate therapies for this condition. DATA SOURCES: A MEDLINE search (1990 to 1995) of the English-language literature, review of a personal library of journals and reprints (1975 to 1995), and review of references selected from the bibliographies of identified articles. Terms used in the MEDLINE search included the names of all autoimmune liver diseases, viral hepatitis and autoimmunity, cryptogenic hepatitis, and overlap syndromes. STUDY SELECTION: All articles that discussed atypical clinical features, mixed diagnostic findings, and variations in treatment response were selected. DATA EXTRACTION: Data were selected from 548 articles. DATA SYNTHESIS: Standardized criteria permit the confident diagnosis of autoimmune hepatitis, but they exclude many patients who have features suggesting autoimmunity. Such patients have findings indicative of both autoimmune hepatitis and another disorder (overlap syndromes) or findings that are inconsistent with the classic definition of autoimmune hepatitis (outlier syndromes). Overlap syndromes include combinations of autoimmune hepatitis and primary biliary cirrhosis, primary sclerosing cholangitis, or chronic viral hepatitis. Treatment of these syndromes requires identification of the predominant disorder and selection of the most appropriate drug regimen. Outlier syndromes include autoimmune cholangitis and cryptogenic chronic hepatitis. Corticosteroids or ursodeoxycholic acid are treatment options for patients with autoimmune cholangitis; corticosteroids can also benefit patients with cryptogenic chronic hepatitis. Grading each clinical feature and developing a composite score can permit comparison of the variants and a determination of the similarity between the variants and autoimmune hepatitis. CONCLUSIONS: Variant forms of autoimmune hepatitis are common. Recognition of them is important in assessing common pathogenic mechanisms, developing effective treatment strategies, and refining classification schemes.

Autoimmune Diseases↗
PubMed2001

[New varieties of lateral metatarsophalangeal dislocations of the great toe].

PURPOSE OF THE STUDY: We report seven cases of traumatic dislocation of the great toe, detailing the anatomy, the mechanism of injury and the radiographic diagnosis. We propose an additional classification based on three hereto unreported cases. MATERIAL AND METHODS: Between october 1994 and october 1997, we treated seven patients with traumatic dislocation of the first metatarso-phalangeal joint of the great toe. There were six men and one woman, mean age 35 years (range 24 - 44 years). Dislocation was caused by motor vehicle accidents in four cases and by falls in three. Diagnosis was made on anteroposterior, lateral and medial oblique radiographs. According to Jahss' classification, there was one type I and three type IIB dislocations. There was also one open lateral dislocation and two dorsomedial dislocations. Only these dorsomedial dislocations required open reduction, done via a dorsal approach. Mean follow-up was 17.5 months (range 9 - 24 months) in six cases. One patient was lost to follow-up. The outcome was good in six cases and poor in one (dorsomedial dislocation). DISCUSSION: Dislocation of the first metatarso-phalangeal joint of the great toe is an uncommon injury. In 1980, Jahss reported two cases and reviewed three others described in the literature. He proposed three types of dislocation based on the feasibility of closed reduction (type I, II and IIB). In 1991, Copeland and Kanat reported a unique case in which there was an association of IIA and IIB lesions. They proposed an addition to the classification (type IIC). In 1994, Garcia Mata et al. reported another case which had not been described by Jahss and proposed another addition. All dislocations reported to date have been sagittal dislocations. Pathological alteration of the collateral ligaments has not been previously reported. In our experience, we have seen one case of open lateral dislocation due, at surgical exploration, to medial ligament rupture and two cases of dorsomedial dislocation due, at surgical exploration, to lateral ligament rupture. CONCLUSION: We propose another additional classification with pure lateral dislocation (type III) and dorso-lateral dislocation (type IL or IIL+), which are related to the formerly described variants.

Accidental Falls↗
PubMedDate not supplied

[Comparative assessment of the WHO and Gilson histological classifications of prostatic neoplasms (taking into account data of ploidy studies)].

We estimated ploidometric nuclear parameters of predominating cell population in various prostatic adenocarcinomas in using WHO vs Glison classification to define advantages of the above classifications. Ploidometry provides information on cell composition and proliferative activity of cells. We observed greater ploidity in different grades of cell atypia. WHO histological classification by differentiation grade corresponds to ploidometric characterization of tumor cell populations but fails to reflect the presence of different histological types of the tumor. Currently introduced classification by Glison is more effective both diagnostically and prognostically as it reveals a dominant histological type of the tumor and shows other variants of tumor growth progression.

Adenocarcinoma↗
PubMed1991

Familial nephropathic non-neuropathic amyloidosis: clinical features, immunohistochemistry and chemistry.

Classification of familial amyloidosis by the chemical nature of the fibrillar protein has become possible. Most such amyloidogenic proteins so far recognized are variant transthyretins, but two kindreds with the same apolipoprotein AI modification have been reported. We describe the clinical features of another such family in whom petechial skin rash appeared to be a marker for the disease, which was non-neuropathic and of the Ostertag-type. Immunohistochemistry showed the protein to be apolipoprotein AI, but allele-specific DNA amplification indicated that it was not the Arg26 variant previously identified.

Amyloidosis↗
PubMed1977

[Neuroectodermal tumors of the skin (a normative study)].

A group of bioptically examined neuroectodermal tumours of the skin and soft tissues consisting, in particular, of 170 Schwannomas and 350 tumours has been reevaluated in a retrospective study. The following common classification of these tumours has been recommended: I. Tumours of Schwann's cells: 1. neurilemmoma [A and B], 2. neurofibroma [with the following variants v. Recklinghausen's type, plexiform, pigmented, Paccinian, with Meissner-Wagner's bodies and meningiomatous], 3. amputation neuroma, 4. neurosarcoma, 5. others. II. Melanogenic tumours: A. pigmented naevi (junction, mixed, intradermal, epithelioid, clear cell, halo, neurocutaneous, fibrous, blue, proliferating blue, melanotic progonoma, others). -B. praecancerous melanosis. -C. malignant melanoblastoma (common type, from praecancerosis). III. Tumours of ganglion cells: 1. ganglioneuroma, 2. neuroblastoma, 3. paragangliomas (with granules, without granules, alveolar soft part sarcoma).

Ganglioneuroma↗
PubMed1982

[Serological classification of Pseudomonas aeruginosa].

In this work the comparative data on the antigenic schemes of P. aeruginosa proposed by different authors are presented. The scheme of serological grouping, accepted in the USSR, has been brought into accord with the current nomenclature of O-antigens, proposed by Lányi and Bergan. The O-antigen composition of the typing strains belonging to groups 3 and 9 according to the classification of Lányi-Bergan has been deciphered, which allows one to extend the antigenic scheme of P. aeruginosa by introducing new antigenic variants.

Antigens, Bacterial↗