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At least 91 records · Page 5Linked to original sources
PubMed2003

Rare variants of Cutaneous Leishmaniasis: whitlow, paronychia, and sporotrichoid.

Cutaneous Leishmaniasis is endemic in certain areas of Pakistan, with the wet form of the disease being the most prevalent. It has a number of morphological variants, which are dependent on the immune status of the host, the subspecies of the Leishmania, and also, to some extent, on the site of involvement. We describe here a case of Leishmaniasis showing two very rare variants, whitlow and paronychial lesions, occurring concurrently with sporotrichoid spread. The patient responded to intramuscular sodium stibogluconate with resolution of the skin lesions.

Antiprotozoal Agents↗
PubMed1998

Myxoglobulosis, a rare variant of appendiceal mucocele, occurring secondary to an occlusive membrane.

A 77-year-old man presented with altered bowel habit and episodic right lower abdominal discomfort. A barium enema showed a large smooth filling defect in the caecum and at operation his appendix was seen to be hugely distended. Pathological examination showed myxoglobulosis, a rare variant of mucocele of the appendix. The appendiceal orifice was completely occluded by an imperforate membrane with no communication between the appendix and caecum. This is the first published report in the English language of appendiceal myxoglobulosis in association with such an occlusive membrane.

Abdominal Pain↗
PubMed1998

Covered exstrophy: a rare variant.

A case of covered exstrophy without sequestration of a bowel segment is reported. A 4-year-old female presented with dribbling of urine. Treatment to date has been simple excision of the covered membrane with functional closure of the bladder and bilateral posterior iliac osteotomies, with reconstruction of the bladder neck and genitalia to be performed at a later date. The embryogenesis of this rare variant, a review of the reported cases, and management options are discussed. Keyword Covered exstrophy. Exstrophy. Bladder variants

Bladder Exstrophy↗
PubMed2004

Metachronous and multiple aneurysmal bone cysts: a rare variant of primary aneurysmal bone cysts.

In 1942, Jaffe and Lichtenstein introduced the term aneurysmal bone cyst (ABC). Primary ABC is characterized by the presence of spongy or multi-cameral cystic tissue filled with blood. The process is benign, but it is locally destructive and has a high propensity for recurrence. In this paper, we present the third case of multiple metachronous primary ABCs as a rare variant of ABC. We describe the 10-year history of a 12-year-old boy with metachronous multiple primary ABCs at five different sites (right proximal humerus, right ulna, bilateral distal radius and right lateral clavicle). Furthermore, our patient suffered from vascular malformations, such as aortic isthmus stenosis, hypoplastic thoraco-abdominal aorta and bilateral renal artery stenosis. To date, in contrast to solitary ABC, the multiple lesions have been found more frequently in male individuals. Using interphase cytogenetics, we analyzed three of five of the patient's ABCs and one of these was also analyzed by GTG-banding. No chromosomal abnormalities were found. Significantly, we excluded the missense mutation of codon 201 in guanine nucleotide-binding protein 1 gene consistently found in McCune-Albright syndrome (MAS) and in non-MAS cases of polyostotic fibrous dysplasia of bone with or without secondary ABC.

Blood Vessels↗
PubMed1985

Focal cytomegaly of the adult adrenal cortex. A rare variant of black adenoma.

A pigmented adrenocortical nodule was found incidentally in an adrenal gland resected for endocrine manipulation of breast carcinoma. The sharply circumscribed, nonencapsulated nodule was composed of cells with diameters as large as 95 micron. The cells had ample eosinophilic cytoplasm and contained much lipofuscin pigment. Electron microscopy disclosed tubulovesicular mitochondria, lipofuscin pigment, cytoplasmic vacuolization, and lipid without degenerative changes or intranuclear inclusions. This unusual lesion of adult adrenal glands is best considered as a rare variant of adrenocortical black adenoma.

Adenoma↗
PubMed2000

Biliary cystadenoma: rare variant of intrahepatic cystic disease.

Intrahepatic nonparasitic cystic disease is rare and may be of congenital or neoplastic origin. The most frequent symptoms and signs are nonspecific and include pain, nausea, fullness, increased girth, and palpable mass. Interventional therapy is reserved for symptomatic patients, which usually corresponds to cysts >5 cm in diameter. Retrospective analysis revealed 26 cases of intrahepatic cystic disease over 15 years at our institution. We discuss the case of a patient who had bilobular biliary cystadenomatous disease, a rare, benign variant of intrahepatic nonparasitic cystic disease.

Abdominal Pain↗
PubMed1995

Rapid detection of rare variants and common polymorphisms in the APC gene by PCR-SSCP for presymptomatic diagnosis and showing allele loss.

During the course of screening the 5' half of exon 15 of the APC gene for germline and somatic mutations in two groups of patients, those with the inherited cancer prone syndrome adenomatous polyposis coli (APC) or with sporadic colorectal cancer, we have identified a number of intragenic changes that are not associated with the disease phenotype. Four of these changes are rare variants, each confined to one or two families and not detected in 50 additional unrelated people. Two common polymorphisms, at codon 1493 (exon 15I) and codon 1678 (exon 15J), were extensively investigated and found to be in almost complete linkage disequilibrium not only with each other but with a previously described polymorphism at codon 1960 (exon 15N). The rapid and sensitive single strand conformation assay used provides an efficient method for presymptomatic diagnosis using intragenic variants and was additionally used to show allele loss at the APC locus in sporadic colorectal carcinomas.

Adenomatous Polyposis Coli↗
PubMed2025

Rare variants and survival of patients with idiopathic pulmonary fibrosis: analysis of a multicentre, observational cohort study with independent validation.

BACKGROUND: Rare pathogenic variants in telomere-related genes are associated with poorer clinical outcomes in idiopathic pulmonary fibrosis (IPF). We aimed to assess whether rare qualifying variants in monogenic adult-onset pulmonary fibrosis genes are associated with IPF survival. Using polygenic risk scores (PRS), we also evaluated the influence of common IPF risk variants in patients carrying the qualifying variants. METHODS: We identified qualifying variants in telomere and non-telomere genes using whole-genome sequences from individuals clinically diagnosed with IPF and enrolled in the Pulmonary Fibrosis Foundation Patient Registry (PFFPR), a large multicentre, observational cohort study (March 29, 2016 to June 15, 2018, n=888). We also derived a PRS for IPF (PRS-IPF) from known common sentinel IPF variants. The primary outcome was the association between qualifying variants and survival. The secondary outcome was the association between qualifying variants and PRS-IPF. We used logistic regression models adjusted for sex, age at diagnosis, and principal components of genetic heterogeneity to examine the mutual relationship of qualifying variants and PRS-IPF. The association between qualifying variants and PRS-IPF with survival was tested using Cox proportional hazard models adjusted for baseline confounders. Validation of the results was sought in data from an independent multicentre, prospective, observational cohort study of IPF in the UK (PROFILE, May 17, 2010 to Sept 5, 2017, n=472), and results were meta-analysed under a fixed-effects model. FINDINGS: We included 888 patients from PFFPR and 472 from PROFILE, totalling 1360 participants. In the PFFPR, carriers of qualifying variants in monogenic adult-onset pulmonary fibrosis genes were associated with lower PRS-IPF (odds ratio 1·79 [95% CI 1·15-2·81]; p=0·010) and shorter survival (hazard ratio 1·53 [1·12-2·10]; p=7·33 × 10-3). Individuals with the lowest PRS-IPF also had worse survival (1·61 [1·25-2·07]; p=1·87 × 10-4). These findings were validated in PROFILE and the meta-analysis of the results showed a consistent direction of effect across both cohorts. INTERPRETATION: We found non-additive effects between qualifying variants and common risk variants in IPF survival, suggesting distinct disease subtypes and raising the possibility of using PRS to guide sequencing prioritisation. Assessing the carrier status for qualifying variants and modelling PRS-IPF promises to further contribute to predicting disease progression among patients with IPF. FUNDING: Instituto de Salud Carlos III; Instituto Tecnológico y de Eenergías Renovables; Cabildo Insular de Tenerife; Fundación DISA; National Heart, Lung, and Blood Institute of the US National Institutes of Health; and UK Medical Research Council.

Humans↗
PubMed1998

Identification of two rare variants (G-->A at nucleotide 721; C-->T at nucleotide 5200) in the rhodopsin gene. Mutations in brief no. 187. Online.

The authors report two new rare DNA sequence variants in the Rhodopsin gene. This gene is involved in the pathogenesis of some retinal hereditary disorders as Retinitis Pigmentosa. These rare variants are G-->A at nucleotide 721 of the non-coding region and C-->T at nucleotide 5200 within codon 323 which does not alter the aminoacid cysteine. Therefore, they are not implicated in the development of the Retinitis Pigmentosa disease.

Adenine↗
PubMed1999

New mutations, polymorphisms, and rare variants in the ATM gene detected by a novel SSCP strategy.

The gene for ataxia-telangiectasia, ATM, spans about 150 kb of genomic DNA. ATM mutations are found along the entire gene, with no evidence of a mutational hot spot. Using DNA as the starting material, we screened the ATM gene in 92 A-T patients, using an optimized single-strand conformation polymorphism (SSCP) technique that detected all previously known mutations in the polymerase chain reaction (PCR) segments being analyzed. To expedite screening, we sequentially loaded the SSCP gels with three different sets of PCR products that were pretested to avoid overlapping patterns. Many of the DNA changes we detected were intragenic polymorphisms. Of an expected 177 unknown mutations, we detected approximately 70%, mostly protein truncating mutations (that would have been detectable by protein truncation testing if RNA starting material had been available). Mutations have now been defined for every exon of the ATM gene. Herein, we present 35 new mutations and 34 new intragenic polymorphisms or rare variants within the ATM gene. This is the most comprehensive compilation of ATM polymorphisms assembled to date. Defining polymorphic sites as well as mutations in the ATM gene will be of great importance in designing automated methods for detecting mutations.

Ataxia Telangiectasia↗
PubMed2002

Pathogenic mutations and rare variants of the APC gene identified in 75 Belgian patients with familial adenomatous polyposis by fluorescent enzymatic mutation detection (EMD).

Familial adenomatous polyposis (FAP) is a dominant inherited colorectal cancer syndrome which is caused by germline mutations in the adenomatous polyposis coli (APC) gene. Enzymatic mutation detection (EMD) has potential advantages over the standard protein truncation test (PTT) that is currently used in screening the APC gene for mutations. First we wanted to validate the EMD technique in comparison to PTT. Secondly, we wanted to develop an efficient working protocol for EMD screening of APC. Seventy-five unrelated patients were screened for mutations. All mutations that had previously been detected by PTT were also identified by EMD; the sizes of the cleavage fragments were as expected according to the position of the mutations within the amplicons. A new screening strategy based on EMD allows the analysis of the APC gene in 31 overlapping PCR fragments. In total, EMD efficiently detected the 26 truncating mutations in this series. In addition, two rare variants were also detected: the first is the typical Ashkenazi missense mutation I1307K while the second variant, E1317Q, has been identifed in Belgian patients and controls, and should no longer be considered as a pathogenic mutation, but rather classified as a polymorphism.

Adenomatous Polyposis Coli↗
PubMed2005

Sclerosing rhabdomyosarcoma: a rare variant with predilection for the head and neck.

OBJECTIVES/HYPOTHESIS: Sclerosing rhabdomyosarcoma is a newly described variant of rhabdomyosarcoma with a predilection for the head and neck. Little has been written on the topic, because of the scarcity of the disease and its recent recognition as a distinct entity. The present report describes the fifth confirmed case of sclerosing rhabdomyosarcoma and is the first report in the otolaryngology literature. STUDY DESIGN: Case report. METHODS: The authors have reported the case of a 66-year-old woman with a 35-year history of heavy cigarette smoking and daily alcohol consumption and a 2-month history of progressive dysphagia and dysarthria secondary to an enlarging tongue mass. Urgent tracheotomy was performed for impending respiratory embarrassment. Direct laryngoscopy revealed a bulky, exophytic mass involving the base of tongue. Specimens were obtained and submitted for analysis. RESULTS: Initial frozen-section analysis of the specimens favored carcinoma, although subsequent immunohistochemical analysis disproved this. The diagnosis of sclerosing rhabdomyosarcoma was based on microscopic appearance and patterns of gene expression, including the expression of desmin and myogenin. A search of the literature revealed only four confirmed cases of sclerosing rhabdomyosarcoma. With the inclusion of the oropharyngeal tumor in the present report, three of the five confirmed cases have occurred in the head and neck. CONCLUSION: Sclerosing rhabdomyosarcoma is a rare variant of rhabdomyosarcoma that has a predilection for the head and neck. The clinical presentation may mimic carcinoma. The otolaryngologist-head and neck surgeon must be familiar with this disease entity.

Aged↗
PubMed1997

An unusual G-negative band within 1qh region a rare variant or an abnormality?

Morphological variations due to heterochromatic DNA of the secondary constriction region (qh) of human chromosome 1 are considered normal. The structural abnormalities involving or in association within the qh region have been difficult to characterize by routine cytogenetic methods and in turn have often gone undetected. In the past, the presence of a G-negative band within the qh region of chromosome 9 has been considered as a rare or unusual variant. Fortuitously, we were referred two cases where a G-negative band was embedded within the secondary constriction region of chromosome 1. Whole chromosome #1 specific painting probe, did hybridize to the band. Both patients have speech delay. Unfortunately, the parents were not available to confirm the mode of inheritance, nor could a definite conclusion be reached concerning its morbidity. Nevertheless, we are tempted to hypothesize that this is an unusual variant where a G-negative band apparently became genetically inert when it was sandwiched between two blocks of heterochromatin. Similar to a rare variant of chromosome 9 it could be found in the qh region of chromosome 16 as well, whose clinical consequences remain obscure.

Child, Preschool↗
PubMed2000

Human 18 kDa phosphotyrosine protein phosphatase (ACP1) polymorphism: studies of rare variants provide evidence that substitutions within or near alternatively spliced exons affect splicing result.

The mammalian low molecular weight phosphotyrosine protein phosphatase is expressed as two distinct isoforms. The human 'fast' and 'slow' isoforms differ only in the sequence of an internal segment of 34 residues, and the ACP1 gene contains two adjacent exons (E3F and E3S) which encode these segments. We have previously suggested that the fast and slow isoforms are generated by mutually exclusive pre-mRNA splicing of E3F and E3S. The common alleles ACP1*A, *B and *C express the fast and slow isoforms in different ratios. The *A and *C alleles differ from *B by C --> T transitions in E3S and E3F respectively. To test the idea that the fast : slow ratio is determined by nucleotide substitutions in the E3F-I3F-E3S region, four groups of rare ACP1 variants with unusual fast : slow ratios and the rare *E and *R alleles, expressing fast∶slow ratios similar to *C and *B, respectively, were analysed. Gene segments of the I2-I3S region were amplified by PCR and analysed by SSCP and variant bands were excised and sequenced. For each of the rare isozymic variants one of six different nucleotide substitutions in E3F (nts+42, +85, +109, +110), I3F (nt+1) and I3S (nt+8) was observed. The *E and *R alleles showed C and B sequence, respectively, in accordance with the fast : slow ratio. The results support the hypothesis that the fast : slow ratio is constitutive.

Alternative Splicing↗
PubMed1998

Rosaceous lymphedema: a rare variant of a common disorder.

Rosaceous lymphedema is considered to be a rare and disfiguring variant of acne rosacea. Cases remain difficult to treat and can challenge afflicted patients both cosmetically and psychologically. We describe an unusual presentation of rosaceous lymphedema and review the differential diagnosis of persistent facial edema.

Biopsy, Needle↗
PubMed1977

The vitamin D binding of the common and rare variants of the group-specific component (Gc). An autoradiographic study.

The vitamin D3 binding properties of the common and rare Gc variants were examined. Vitamin D3 labeled with 14C was added to serum. Gc phenotypes were demonstrated autoradiographically following separation by immunofixation electrophoresis on agarose. This qualitative analysis did not reveal differences in vitamin D3 binding by the group-specific components of the common types Gc 1-1, Gc 2-1, and Gc 2-2. The double-band variants Gc Darmstadt, Gc Y/Ab, Gc Toulouse, Gc Norway, and Gc Caucasian were examined; the phenotypes Gc Ab-Ab, Gc Ab-1, Gc Ab-1, Gc Ab-2, Gc T-1, Gc T-2, Gc Norw-2, and Gc 1-Cau showed normal D3 binding. The double bands of Gc Darmstadt in the phenotype D-2 appeared somewhat weak. The single-band mutants Gc Wien, Gc Chippewa, Gc Opava, and Gc Z were analyzed; the phenotypes Gc W-1, Gc W-2, Gc Chip-1, Gc Chip-2, Gc 1-Op, Gc Op-2, Gc 1-Z, and Gc 2-Z showed normal D3 binding. A mutant in the Gc system with clearly defective vitamin D3 binding properties remains to be delineated.

Alpha-Globulins↗
PubMed2001

[Rare variants of formation of human brachial nerves and arteries].

In the course of preparing muscular and neurovascular specimen of human right arm a combination of several rare anatomic variants was discovered which, to the authors opinion, are worth attention. 1. Formation of the median nerve at the border between middle and inferior thirds of brachium. 2. Variant of n. musculocutaneus origination from the lateral fascicle of plexus brachialis by several branches. 3. Variant of n. antebrachii cutaneous lateralis origination from the lateral fascicle by two branches. 4. Radial artery branching from humeral artery at the level of middle third of the brachium. 5. Three heads were discovered in m. biceps brachii. The variants described are interesting from scientific and clinical interest: they contribute to general conception of human anatomy and clinical manifestations of injuries of brachial nerves and arteries.

Adult↗
PubMed2001

Congenital absence of aortic valvar leaflets: a rare variant of the hypoplastic left heart syndrome.

Congenital absence of aortic valvar leaflets is a rare and fatal variant of the hypoplastic left heart syndrome. We describe a recent patient seen at our institution with this lesion, illustrating a combined echocardiographic and angiographic approach that delineates both anatomy and physiology. The early mortality experienced in previous reports, as well as unsuccessful surgical palliation in our case, should promote further discussion regarding the optimal treatment.

Aortic Valve↗