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H Hintner

Publications and source records attributed to H Hintner.

At least 37 records · Page 2Linked to original sources
PubMed2001

Large melanocytic nevi in hereditary epidermolysis bullosa.

Large melanocytic nevi occurring in areas of former blistering in patients with hereditary epidermolysis bullosa (EB) pose a problem to the clinician with regard to prognosis and therapy because they may show clinical and histopathologic features strikingly resembling malignant melanoma. To investigate clinical and histologic criteria as well as the biologic behavior of these nevi, pigmented lesions of 12 patients (EB simplex, n = 1; junctional EB, n = 7; dystrophic EB, n = 4) of the Austrian EB registry were analyzed. Clinically, the nevi are up to palm sized, are initially very dark, and may exhibit stippled pigmentation and irregular borders that outline areas of former blisters. Over time they usually lose pigment, the surface gets papillomatous, and finally they acquire a shagreen-like appearance. Histopathologically, the nevi frequently exhibit a compound congenital or persisting nevus/pseudomelanoma pattern. Despite this combination of features, no malignant transformation of the nevi has been seen by us even after 20 years of prospective surveillance. Because nevi with these criteria do not fit in any of the known categories, we suggest the term EB nevi.

Adolescent↗
PubMed1999

Revertant mosaicism: partial correction of a germ-line mutation in COL17A1 by a frame-restoring mutation.

Generalized atrophic benign epidermolysis bullosa is an autosomal recessive subepidermal blistering disease typified by null mutations in COL17A1. In 1 large kindred, affected individuals were homozygous for a 2-bp deletion in COL17A1, 4003delTC, which resulted in a downstream premature termination codon, nonsense-mediated mRNA decay, and abrogation of type XVII collagen synthesis. Interestingly, 1 of these patients, although phenotypically identical to her affected siblings, showed focal expression of type XVII collagen in epidermal basement membrane in a pattern suggestive of revertant mosaicism. When studies of randomly obtained epidermal, oromucosal, and peripheral blood cells failed to identify the genetic basis of this apparent mosaicism, microscopic subpopulations of potentially revertant epidermal cells (i.e., those overlying basement membrane containing type XVII collagen) were selectively isolated using laser capture microdissection. Analysis of DNA and RNA from these cells revealed a second mutation, 4080insGG, on 1 allele of COL17A1. This 2-bp insertion corrected the reading frame just proximal to the premature termination codon, countered nonsense-mediated mRNA decay, and allowed protein production by patient keratinocytes in vivo and in vitro. These studies elucidate the molecular basis of a novel form of revertant mosaicism in humans.

Alleles↗
PubMed1999

[Prenatal diagnosis of recessive hereditary dystrophic epidermolysis bullosa with haplotype analysis of the type VII collagen gene].

DNA-based prenatal testing of the fetal genotype was performed in a family at risk for recurrence of recessive dystrophic epidermolysis bullosa (RDEB). DNA from cultured fibroblasts and leukocytes from the peripheral blood of the previously affected offspring, DNA from parental leukocytes and DNA from fetal tissue obtained by chorionic villus biopsy was analysed by direct PCR amplification of known polymorphic regions within or flanking the type VII collagen gene, the candidate gene in RDEB. One flanking marker (D3S2/Mspl) as well as two intragenic polymorphisms (C7/Mspl, C7/Eco01091) in exons 30 and 84 were informative in this family. Thus, based on the haplotype analysis and the lack of evidence for locus heterogeneity in RDEB, a phenotypically healthy child was predicted. This prediction was confirmed by the birth of a healthy female infant. The study reports successful determination of the fetal genotype by PCR-based prenatal diagnosis in a family at risk for recurrence of severe RDEB.

Adult↗
PubMed1999

[Acatalasemia--Takahara's disease].

The case of a 30 year old man with acatalasemia is presented. The congenital disorder is charaterized by a lack or major reduction of catalase, an enzyme that catalyzes the decomposition of hydrogen peroxide to oxygen and water. The defect is inherited in an autosomal recessive fashion. Occasionally the defect manifests as progressive oral gangrene or Takahara's, disease.

Acatalasia↗
PubMed1999

Ocular involvement in IgA-epidermolysis bullosa acquisita.

Epidermolysis bullosa acquisita (EBA) is an autoimmune bullous disease with frequent ocular involvement, but visual loss is rare. In contrast, EBA patients with predominant IgA autoantibodies more frequently develop severe ocular involvement, which tends to be refractory to therapy. We report two patients with 'IgA-EBA' with ocular involvement. Both initially presented with a generalized bullous disease, and direct immunofluorescence microscopy demonstrated IgA in the basement membrane zone of the skin, and in the conjunctiva and cornea of patient 1. On salt-split patient skin, IgA was found predominantly on the dermal side of the artificial split in both patients. Direct immunoelectron microscopy demonstrated IgA below the lamina densa in close association with the anchoring fibrils in both patients. In patient 1, who had a prolonged course of the disease, the skin disorder responded well to treatment with cyclosporin, but the ocular involvement ended in bilateral blindness despite repeated surgical treatment. In patient 2, the blister formation and scarring conjunctivitis was stopped by a combination of prednisolone and colchicine. These patients show that in subepithelial blistering diseases, early delineation of disease nosology is critical to detect subtypes with severe ocular involvement such as 'IgA-EBA'. In addition, colchicine may be a valuable alternative in the treatment of EBA with ocular involvement.

Adult↗
PubMed1998

[Hereditary angioedema in the German-speaking region].

A multicentre, retrospective study of hereditary deficiency of C1-esterase inhibitor (C1-INH) function, a deficiency which clinically manifests as hereditary angioedema (HAE), was performed in six centres in Germany, Austria and Switzerland. 242 individuals were registered with proven functional or quantitative deficiency of C1-INH who belonged to kindered with disease manifestation in 2 to 6 generations. Considering the total population in the three countries and the number of registered individuals, a frequency of the deficiency of 0.02 x 10(-4) was calculated. As this epidemiological study involved only 6 centres, a 10 to 100 times higher frequency of C1-INH deficiency is estimated to be a more realistic value. Out of the 242 registered individuals 110 were evaluated for type and location of clinical manifestation of the deficiency, the laboratory data and the therapy outcome. 86 (78.2%) of the patients belonged to the "common type" and 24 (21.8%) to the "variant type" of HAE. In 53.9% of the cases first manifestation of the disease was before the age of 20 years. In only 3.9% of the patient population did the disease begin after 40 years of age. A mean time lag of 5,3 years was observed, between the first manifestation and correct diagnosis. Initial diagnosis was correct in only 31.8% of the cases of which dermatologists provided 51.7%. False diagnoses include urticaria (41.3%), allergy (20%), acute abdomen (18.7%), angina (8%), rheumatoid disease (5.3%) and intracranial haemorrhage, CNS tumour, epilepsy, migraine (5.3%). The distribution pattern of HAE resembled that of intolerance reactions and pseudoallergies. Urticarial lesions were not associated with C1-INH deficiency. 24% of the patients had at least one episode of laryngeal edema. 40% of patients were unable to identify a trigger of edema formation. The others indicated as triggers trauma, hormonal changes, mental stress, insect stings and in a few cases food and drugs. Menstruation and oral contraceptives aggravated or made disease manifestations more frequent. In contrast, during pregnancy in many cases clinical manifestations improved and delivery posed no problems. The possibility of HAO is very much suggested by the tailure of edema to respond to classical anti-allergic therapy. Therapy of choice of acute attacks is C1-INH concentrate. No side reactions, antibody formation or virus transmission have been observed. For long term prophylaxis danazol, an attenuated androgen, or tranexamic acid, a protease inhibitor, was chosen. The daily dose of danazol should be kept as low as possible because of its anabolic, anti-estrogenic, anti-gestagenic, and anti-gonadotropic effects. Indeed, adverse reactions were observed in 41.7% of patients receiving danazol. Frequencies of adverse reactions were twice as common in women as in men. Adverse reactions were dose dependent and reversible except for one woman with irreversible deepening of her voice. Measuring C1r is a effective way to assess C1-INH function and monitor therapy.

Adolescent↗
PubMed1998

A deletion mutation in COL17A1 in five Austrian families with generalized atrophic benign epidermolysis bullosa represents propagation of an ancestral allele.

Patients with generalized atrophic benign epidermolysis bullosa, a usually nonlethal form of junctional epidermolysis bullosa, have generalized blistering, nail dystrophy, patchy alopecia, and dental abnormalities. Skin fragility in most cases is due to mutations in the gene encoding type XVII collagen (COL17A1). Recently, we reported five Austrian families with generalized atrophic benign epidermolysis bullosa who share the same COL17A1 mutation. Affected individuals in three families are homozygous for 4003delTC, whereas those in two others are compound heterozygotes. To determine if the occurrence of 4003delTC in these unrelated families signifies propagation of an ancestral allele or a mutational hot spot, haplotypes were determined for polymorphisms both within and flanking COL17A1. Five intragenic polymorphisms were chosen based on their informativeness. One of these, not previously reported, was 2988 A or C that introduces a new restriction site for Eco0109 I. All the 4003delTC alleles showed the same haplotype for these five polymorphic markers. Fourteen microsatellite polymorphisms were selected based on their high heterozygosity and their location within 10q23-q25 near COL17A1. Three families shared microsatellite polymorphisms covering at most 19 cM, whereas the others shared smaller regions consistent with cross-over events during passage of this mutation through several generations. These results indicate that 4003delTC occurs on a single ancestral allele.

Alleles↗
PubMed1998

Cycloheximide facilitates the identification of aberrant transcripts resulting from a novel splice-site mutation in COL17A1 in a patient with generalized atrophic benign epidermolysis bullosa.

Patients with generalized atrophic benign epidermolysis bullosa often show decreased expression of type XVII collagen, a transmembrane hemidesmosomal protein encoded by COL17A1. This report documents a novel splice-site mutation in COL17A1 in a patient with generalized atrophic benign epidermolysis bullosa, and applies a new methodology to define and characterize the resulting mRNA splice variants. Mutational analysis of COL17A1 identified a maternally inherited G-to-T transversion at the -1 position of exon 32. This acceptor splice-site mutation led to the formation of aberrant transcripts present at extremely low levels. Based on our recent finding that cycloheximide stabilized mutant COL17A1 transcripts in keratinocytes homozygous for a frameshift mutation, the effects of the splice-site mutation on splicing of COL17A1 transcripts were determined using reverse transcriptase polymerase chain reaction of total RNA from keratinocytes incubated for 2.5 h in the presence or absence of 10 microg cycloheximide per ml. Using this approach, an abnormally spliced transcript was identified that contains an extra 264 bases upstream from exon 32, resulting in a premature termination codon 27 bp downstream from the cryptic splice site. Three other splice variants, including one derived from the skipping of exon 32, were also identified. These results indicate the usefulness of cycloheximide treatment in evaluating the abnormal processing of mRNA due to splice-site mutations, because: (i) aberrant splicing often generates a premature termination codon, (ii) transcripts with premature termination codons can occur at low or undetectable levels due to nonsense-mediated mRNA decay, and (iii) the levels of these transcripts can be increased by cycloheximide.

Adult↗
PubMed1997

Intravenous immunoglobulin treatment in therapy-resistant epidermolysis bullosa acquisita.

Epidermolysis bullosa acquisita is an uncommon autoimmune bullous disease of the skin and mucous membranes. It is chronic, disabling, and difficult to treat. We describe a case of severe epidermolysis bullosa acquisita of 7 years' duration that had been treated with azathioprine, corticosteroids, chlorambucil, plasma exchanges, cyclophosphamide, cyclosporine, and colchicine without any lasting effect. Seven cycles of treatment were administered with immunoglobulin given intravenously at a low dose, 40 mg/kg body weight daily for 5 days. The patient was free of disease for 10 months after the initiation of therapy. We suggest that low-dose regimens of immunoglobulins may be as effective in this disease as the high-dose regimens suggested in the literature, and at much lower cost.

Adult↗
PubMed1997

Premature termination codons are present on both alleles of the bullous pemphigoid antigen 2/type XVII collagen gene in five Austrian families with generalized atrophic benign epidermolysis bullosa.

Patients with generalized atrophic benign epidermolysis bullosa (GABEB), an inherited subepidermal blistering disease, often have no immunologically detectable bullous pemphigoid antigen 2 (BPAG2) in their epidermal basement membrane. Recently, we analyzed the BPAG2 gene (GenBank no. M91669) in an Austrian family with GABEB and identified a homozygous deletion mutation, 4003delTC, that results in a downstream premature termination codon (PTC). This mutation has now been identified in additional descendants, suggesting transmission of this mutant allele through at least six generations. Screening of four other Austrian GABEB families revealed that affected members were homozygous for 4003delTC in two cases and heterozygous in two others. In the latter, mutational analysis identified two novel nonsense mutations, Q1403X and G803X, that were confirmed by restriction endonuclease digestions. Thus, PTCs on both alleles of BPAG2 are present in all of these GABEB families. Immunoprecipitation and northern blot studies of cultured keratinocytes from homozygous GABEB patients show that 4003delTC results in undetectable levels of BPAG2 protein and mRNA-findings consistent with the process of nonsense-mediated mRNA decay. Incubating keratinocytes with cycloheximide increased BPAG2 mRNA to a level detectable by northern analysis. When the latter was used in reverse transcription-PCR studies, the mutation was demonstrated, suggesting that cycloheximide may allow mutational analysis in cases where low transcript levels have previously thwarted RT-PCR studies. These findings account for the absence of BPAG2 in GABEB patients and attest to the importance of this protein in adhesion of epidermis to epidermal basement membrane.

Alleles↗
PubMed1997

Generalized atrophic benign epidermolysis bullosa.

Junctional EB was once considered a uniformly fetal autosomal recessive skin disease. One of the first and best characterized forms of generalized JEB that has a more favorable prognosis was GABEB. Since its initial description in 1976, many additional cases have been compiled, all sharing the features of chronic blistering from birth, nail dystrophy, hair loss, and abnormal teeth. In addition, some patients have large melanocytic nevi that form at sites of prior blisters. The first clues as to the protein defective in these patients was provided by immunofluorescence microscopy studies, which showed absent or decreased expression of type XVII collagen in these patient's epidermal BM. This protein was a promising candidate because it is located in the ultrastructural plane where blisters from in patients with GABEB. It is also the same hemidesmosomal protein against which antibodies are directed in patients with autoimmune blistering diseases: bullous, gestational, and cicatricial pemphigoid. The demonstration of decreased expression of type XVII collagen in patients with GABEB pointed the way to a crucial distinction that could not be based on clinical and histologic findings--that of discriminating infants with GABEB from those with the lethal Herlitz variant of JEB. These two diseases may be differentiated because decreased expression of type XVII collagen is found exclusively in GABEB, whereas decreased expression of laminin 5 is most likely associated with Herlitz JEB. The molecular basis of GABEB has been determined. The immunofluorescence microscopy studies mentioned above directed mutation studies to the COL17A1 gene. Several mutations in COL17A1 have been described in patients with GABEB, almost all of which result in a PTC. As a consequence of the PTC, mutant COL17A1 transcripts are rapidly degraded by nonsense-mediated mRNA decay, blocking production of type XVII collagen from the mutant allele. Heterozygous carriers of the mutation are thus rendered untouched by the mutation. In the homozygous state, however, this results in the absence of this vital adhesion protein, leading to chronic blistering and skin fragility observed in these patients. These studies also significantly increase our knowledge about the normal functions of type XVII collagen. The fact that patients deficient in type XVII collagen have fragile skin attests to the role of this protein in the adhesion of basal keratinocytes to epidermal BM. The severity of GABEB, however, is much less than that observed in patients with a complete deficiency of laminin 5, suggesting that type XVII collagen functions cooperatively with other hemidesmosomal proteins in promoting adhesion. Studies using GABEB keratinocytes will help characterize these kinds of interactions. The ultimate prospect of mutation analysis in these patients is the hope of correcting their genetic defect and curing their disease. Until then, the physician plays an important role in making the diagnosis, providing general supportive skin care, advising avoidance of trauma, treating infections, and supporting the patient's psychosocial development. Further studies of patients with GABEB will lead to new therapeutic approaches, as well as reveal additional complex functions of type XVII collagen not only in skin, but also in hair, teeth, and nails.

Collagen↗
PubMed1996

A homozygous deletion mutation in the gene encoding the 180-kDa bullous pemphigoid antigen (BPAG2) in a family with generalized atrophic benign epidermolysis bullosa.

The 180-kDa bullous pemphigoid antigen (BPAG2) is a candidate gene/protein for mutations in some forms of junctional epidermolysis bullosa. In this study, we searched for mutations in BPAG2 in a large Austrian pedigree with generalized atrophic benign epidermolysis bullosa, a distinct nonlethal form of junctional epidermolysis bullosa, using polymerase chain reaction amplification of genomic DNA, heteroduplex analysis of the polymerase chain reaction products, and direct nucleotide sequencing. We identified a homozygous 2-bp deletion within the coding region of BPAG2 in the affected individuals. This mutation results in a frameshift and downstream stop codons on both alleles, predicting an absence of functional protein. These findings illustrate the molecular basis of the skin fragility in this family and attest to the importance of the 180-kDa bullous pemphigoid antigen in the attachment of the epidermis to the underlying dermoepidermal basement membrane.

Autoantigens↗
PubMed1996

Immunoglobulin A (IgA) deposits in lesional skin of a patient with blepharochalasis.

We describe a 21-year-old male patient with blepharochalasis, a form of localized acquired cutis laxa. He had a 13-year history of recurrent swelling attacks of the eyelids of unknown origin leading to periocular localized cutis laxa. Histology of lesional skin confirmed almost complete loss of elastic fibres in the reticular and papillary dermis. Immunofluorescence and immunoelectron microscopy studies showed abundant immunoglobulin A (IgA) deposits around the remaining elastic fibres. Control skin of the forearm was negative. These findings support the hypothesis that immunopathogenetic mechanisms may contribute to the elastolytic process of blepharochalasis.

Adult↗
PubMed1995

Diminished expression of the extracellular domain of bullous pemphigoid antigen 2 (BPAG2) in the epidermal basement membrane of patients with generalized atrophic benign epidermolysis bullosa.

Generalized atrophic benign epidermolysis bullosa (GABEB) is a nonlethal form of junctional epidermolysis bullosa characterized by generalized skin and mucosal blisters that heal with atrophy; other features include alopecia, nail dystrophy, large melanocytic nevi, and autosomal recessive inheritance. The specific aim of this study was to identify an abnormality in epidermal basement membrane adhesion molecules in well characterized GABEB patients that would explain why these subjects' epidermis separates from their epidermal basement membrane. Cryostat sections of nonlesional skin from 8 GABEB patients in 5 different families as well as skin from normal volunteers (controls) were studied by indirect immunofluorescence microscopy using rabbit antiserum directed against a BPAG1 fusion protein or monoclonal antibodies directed against the extracellular domain of BPAG2 (HD18 and 233), epiligrin (P1E1), laminin 5 (GB3), types IV and VII collagen, or integrin subunits alpha 2, alpha 3, beta 1, alpha 6, or beta 4. In these studies, monoclonal antibodies HD18 and 233 showed no reactivity and diminished reactivity, respectively, to the epidermal BM of all GABEB patients. Interestingly, in one patient, the absent or diminished reactivities of monoclonal anti-BPAG2 antibodies were limited to well demarcated portions of an otherwise intact epidermal basement membrane. Moreover, BPAG1, epiligrin, laminin 5, types IV and VII collagen, and all integrin subunits under study were expressed in the same manner in both GABEB and normal human skin. These findings identify an abnormality in the extracellular domain of BPAG2 in the skin of GABEB patients. BPAG2 (type XVII collagen) is a transmembrane, hemidesmosome-associated molecule whose extracellular domain resides at the exact level where blisters develop in the skin of patients with GABEB.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗