1/7. pityriasis rubra pilaris with acantholysis and lichenoid histology.Acantholytic foci have been reported several times in pityriasis rubra pilaris (PRP). Lichenoid tissue reactions were also mentioned in the literature regarding PRP. We report a 58-year-old patient who, after having colon cancer, had PRP with biopsies showing acantholytic lesions and a heavy lichenoid lymphocytic infiltration. Investigation by serial sectioning of the acantholytic lesion suggested an involvement of the intraepidermal eccrine duct and further investigation with carcinoembryonic antigen (CEA) staining demonstrated a CEA-positive eccrine duct in the acantholytic foci. We suggest that acantholysis in PRP is induced by proteolytic enzymes, urea, and other substances in eccrine sweat in keratin-plugged acrosyringia. This patient had a combination of three relatively rare features of PRP-acantholysis, lichenoid reaction, and a cancer background.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/7. classification, clinical manifestations, and immunopathological mechanisms of the epithelial variant of paraneoplastic autoimmune multiorgan syndrome: a reappraisal of paraneoplastic pemphigus.BACKGROUND: Recent studies suggest that paraneoplastic pemphigus (PNP) is a heterogeneous autoimmune syndrome involving several internal organs and that the pathophysiological mechanisms mediating cutaneous, mucosal, and internal lesions are not limited to autoantibodies targeting adhesion molecules. OBJECTIVE: To classify the diverse mucocutaneous and respiratory presentations of PNP and characterize the effectors of humoral and cellular autoimmunity mediating epithelial tissue damage. methods: We examined 3 patients manifesting the lichen planus pemphigoideslike subtype of PNP. A combination of standard immunohistochemical techniques, enzyme-linked immunosorbent assay with desmoglein (DSG) baculoproteins, and an immunoprecipitation assay were used to characterize effectors of humoral and cellular autoimmunity in patients with PNP and in neonatal wild-type and DSG3-knockout mice with PNP phenotype induced by passive transfer of patients' IgGs. RESULTS: In addition to the known "PNP antigenic complex," epithelial targets recognized by PNP antibodies included 240-, 150-, 130-, 95-, 80-, 70-, 66-, and 40/42-kd proteins but excluded DSG1 and DSG3. In addition to skin and the epithelium lining upper digestive and respiratory tract mucosa, deposits of autoantibodies were found in kidney, urinary bladder, and smooth as well as striated muscle. Autoreactive cellular cytotoxicity was mediated by CD8( ) cytotoxic T lymphocytes, CD56( ) natural killer cells, and CD68( ) monocytes/macrophages. Inducible nitric oxide synthase was visualized both in activated effectors of cellular cytotoxicity and their targets. Keratin 14-positive basal epithelial cells sloughed from the large airways and obstructed small airways. CONCLUSIONS: The paraneoplastic disease of epithelial adhesion known as PNP in fact represents only 1 manifestation of a heterogeneous autoimmune syndrome in which patients, in addition to small airway occlusion and deposition of autoantibodies in different organs, may display a spectrum of at least 5 different clinical and immunopathological mucocutaneous variants (ie, pemphiguslike, pemphigoidlike, erythema multiforme-like, graft-vs-host disease-like, and lichen planus-like). We suggest that the more encompassing term "paraneoplastic autoimmune multiorgan syndrome," or PAMS, be applied. The pathophysiological mechanisms of PAMS involve both humoral and cellular autoimmunity responses. Epithelial cell membrane antigens other than DSG1 or DSG3 are targeted by effectors of PAMS autoimmunity. apoptosis of damaged basal cells mediates epithelial clefting, and respiratory failure results possibly from obstruction of small airways with sloughed epithelial cells.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
3/7. Parthenium dermatitis presenting as photosensitive lichenoid eruption. A new clinical variant.Parthenium hysterophorus is the commonest cause of airborne contact dermatitis (ABCD) in india. The disease usually manifests as itchy erythematous, papular, papulovesicular and plaque lesions on exposed areas of the body. Rarely, however, the disease may present as actinic reticuloid or photocontact dermatitis. We have observed a different clinical variant of this disease where certain patients with Parthenium dermatitis have presented with discrete, flat, violaceous papules and plaques on exposed areas of the body closely simulating photosensitive lichenoid eruption. We had 8 patients, 6 males and 2 females between 30 and 62 years of age, with itchy, violaceous, papules and plaques on the face, neck, ears, upper chest and dorsa of the hands for 6 months to 6.5 years. Four of these patients had a history of improvement of the lesions up to 30% in winter and aggravation of lesions on exposure to sunlight. There was no personal or family history of atopy. Cutaneous examination in all patients revealed multiple flat, violaceous, mildly erythematous papules and plaques on the forehead, sides and nape of neck, ears, 'V' area of the chest, and extensor aspects of the forearms and hands. Skin biopsies from these lesions showed features of chronic non-specific dermatitis. Patch testing with standardized plant antigens showed a positive patch test reaction to Parthenium hysterophorus in all patients, with a titre of contact hypersensitivity (TCH) varying from undiluted to 1 : 100. We conclude that Parthenium dermatitis may occasionally present with lesions very similar to the lesions of photosensitive lichenoid eruption in morphology and distribution. This clinical presentation of Parthenium dermatitis needs to be recognized to avoid misdiagnosis.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
4/7. Papulonodular lichenoid and pseudolymphomatous reaction at the injection site of hepatitis b virus vaccination.immunization with the hepatitis b virus (HBV) is effective and safe with an estimated incidence of adverse reactions, either local or systemic, of less than 0.1%. Cutaneous side effects are rare and include lichen planus (LP) and lichenoid reactions. We report the case of a 21-year-old female, in whom a persistent, papulonodular lesion developed at the site of the injection, 6 weeks after the second dose of the HBV. Histological examination revealed lichenoid and pseudolymphomatous features. In addition, sensitization to thiomersal, a vaccine constituent, was documented by patch testing. The association of LP with chronic liver disease is well established. Furthermore, less than 20 cases of lichen or lichenoid reactions, following HBV vaccination, have been reported. Although several arguments have been presented, it is still debated whether there is a causal association or the occurrence of LP following HBV vaccination is a simple coincidence. It has been speculated that a T-cell-mediated, graft-versus-host-like reaction, triggered by a sensitizing protein, is directed against keratinocytes expressing an epitope of hepatitis B surface antigen or a similar epitope. Our case may represent a localized lichenoid reaction to HBV vaccination, a local reactive hyperplasia or a persisting delayed hypersensitivity reaction to a vaccine constituent. This is the first case of a local lichenoid reaction at the injection site of the HBV vaccine, providing further documentation for a causal association linking the HBV vaccine with LP.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
5/7. Oral and genital lichenoid reactions associated with circulating autoantibodies to desmoplakins I and II: a novel target antigen or example of epitope spreading?We describe the first reported case of persistent oral and genital lichenoid reactions associated with circulating antibodies to 250- and 215-kd proteins, compatible with desmoplakin I and II, respectively. We discuss the potential role of epitope spreading, leading to the novel development of specific autoantibodies to desmoplakin.- - - - - - - - - - ranking = 4keywords = antigen (Clic here for more details about this article) |
6/7. Cutaneous tuberculosis and phlyctenular keratoconjunctivitis: a forgotten association.Cutaneous tuberculosis may be associated with concurrent systemic foci in the body such as lung, lymph node, bone or CNS. Phlyctenular keratoconjunctivitis (PKC) is a manifestation of immunological response to a variety of antigens in the eye, tubercular focus (evident or occult) being the commonest in india. Reports in the existing literature have shown lungs and lymph nodes to be the predominant underlying focus associated with PKC, whereas cutaneous tuberculosis has seldom been found in this situation. We report this forgotten association in two children with cutaneous tuberculosis, one each with lupus vulgaris and scrofuloderma, who also had PKC. Interestingly, one of the cases also had simultaneous lichen scrofulosorum, which is also an immunological response to tubercular antigen and manifests in the skin, thus showing immunological manifestation in two different organ systems along with cutaneous focus of tuberculosis.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
7/7. Lichenoid erythrodermic bullous pemphigoid of the African patient.BACKGROUND: lichen planus (LP) pemphigoides is defined by the concurrence of bullous pemphigoid (BP) and LP lesions. However, other autoimmune bullous skin diseases such as paraneoplastic pemphigus or bullous lupus erythematosus may also be associated with lichenoid eruptions. OBJECTIVE: Our purpose was to describe 3 African patients with a similar form of lichenoid erythrodermic BP. methods: medical records of the 3 patients were reviewed for clinical, histologic, and biologic data. The ultrastructural localization of autoantibody deposits was studied by direct and indirect immunoelectron microscopy. The antigenic specificities recognized by the patients' sera were analyzed by immunoblotting on human epidermal extracts. RESULTS: Three black African men had a severe lichenoid erythroderma associated with BP lesions involving the skin and mucosa. Histologic and direct immunofluorescence examination of skin and mucosal lesions were consistent with the diagnosis of BP associated with a lichenoid dermatitis. Immunoblot analysis of sera detected anti-BPAG1 and anti-BPAG2 antibodies and immunoelectron microscopy showed IgG deposits localized in the lamina lucida and the hemidesmosomes. The 3 patients were natives of an area near the senegal River and had the common HLA-DR10 haplotype. CONCLUSION: The clinical and histologic features of these 3 patients were distinct from classic LP pemphigoides. Their common geographic origin and the presence of the HLA-DR10 haplotype suggest that these cases represent a particular type of lichenoid erythrodermic BP, which is probably determined by genetic factors.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |