Periocular molluscum contagiosum: six different clinical presentations.

PURPOSE: To describe the different clinical presentations of periocular molluscum contagiosum (MC) lesions and their epidemiological, clinical and histopathological features. METHODS: Medical records and histopathological sections of all cases of periocular MC treated at the oculoplastic clinic of the Goldschleger Eye Institute, Sheba Medical Center, Israel, between 1995 and 2016 were retrospectively reviewed. The following data were extracted: gender, age at the time of MC diagnosis, immune competency, location of the periocular lesions, number of lesions, dimensions of the lesions, clinical presentation, histopathological features, suspected clinical diagnosis before histopathological diagnosis and treatment. RESULTS: The series was composed of 41 patients (19 males, 22 females) whose mean age at presentation was 20.41 â€Š± â€Š21.10 years (range 1-71 years). Only one patient was immunosuppressed. The cases were classified into six proposed clinical presentations: 'umbilicated nodular', 'big/giant', 'conglomerated', 'erythematous', 'inflamed' and 'pedunculated'. CONCLUSION: This is the first time that different clinical types of MC lesions are labelled. The current evidence also indicates that MC lesions should be suspected not only in children and in immunosuppressed adult patients but also in immunocompetent patients of all ages.

Molluscum Contagiosum Virus Transcriptome in Abortively Infected Cultured Cells and a Human Skin Lesion.

UNLABELLED: Molluscum contagiosum virus (MOCV), the only circulating human-specific poxvirus, has a worldwide distribution and causes benign skin lesions that may persist for months in young children and severe infections in immunosuppressed adults. Studies of MOCV are restricted by the lack of an efficient animal model or a cell culture replication system. We used next-generation sequencing to analyze and compare polyadenylated RNAs from abortive MOCV infections of several cell lines and a human skin lesion. Viral RNAs were detected for 14 days after MOCV infection of cultured cells; however, there was little change in the RNA species during this time and a similar pattern occurred in the presence of an inhibitor of protein synthesis, indicating a block preventing postreplicative gene expression. Moreover, a considerable number of MOCV RNAs mapped to homologs of orthopoxvirus early genes, but few did so to homologs of intermediate or late genes. The RNAs made during in vitro infections represent a subset of RNAs detected in human skin lesions which mapped to homologs of numerous postreplicative as well as early orthopoxvirus genes. Transfection experiments using fluorescent protein and luciferase reporters demonstrated that vaccinia virus recognized MOCV intermediate and late promoters, indicating similar gene regulation. The specific recognition of the intermediate promoter in MOCV-infected cells provided evidence for the synthesis of intermediate transcription factors, which are products of early genes, but not for late transcription factors. Transcriptome sequencing (RNA-seq) and reporter gene assays may be useful for testing engineered cell lines and conditions that ultimately could provide an in vitro replication system. IMPORTANCE: The inability to propagate molluscum contagiosum virus, which causes benign skin lesions in young children and more extensive infections in immunosuppressed adults, has constrained our understanding of the biology of this human-specific virus. In the present study, we characterized the RNAs synthesized in abortively infected cultured cells and a human skin lesion by next-generation sequencing. These studies provided an initial transcription map of the MOCV genome, suggested temporal regulation of gene expression, and indicated that the in vitro replication block occurs prior to intermediate and late gene expression. RNA-seq and reporter assays, as described here, may help to further evaluate MOCV gene expression and define conditions that could enable MOCV replication in vitro.

Molluscum contagiosum. A case report with fine needle aspiration cytologic diagnosis and ultrastructural features.

BACKGROUND: Cytomorphologic and ultrastructural features of molluscum contagiosum, a rare skin lesion of viral etiology, are presented. CASE: A 4-month-old female was referred for fine needle aspiration cytology of papules over the back and chest wall. A Giemsa-stained preparation of whitish material aspirated from the chest wall nodule showed numerous large, intracytoplasmic, basophilic bodies that pushed the host cell nucleus to the periphery, giving a signet-ring appearance to a few cells. A cytologic diagnosis of molluscum contagiosum was suggested. On electron microscopy numerous intracytoplasmic viral particles were demonstrated, thus confirming the cytologic diagnosis. CONCLUSION: In clinically unsuspected cases, the cytologic diagnosis of molluscum contagiosum can be suggested by demonstrating pathognomonic molluscum bodies in aspirated material.

Two major antigenic polypeptides of molluscum contagiosum virus.

A library of molluscum contagiosum virus (MCV) transferred into the cowpox vector expression system was screened with 12 sera from molluscum patients. Two recombinant proteins of 70 and 34 kDa were detected by immunoblotting and mapped to the open-reading frames MC133L and MC084L, respectively. Consensus sites were found between the C-terminus of the 70-kDa MCV protein and the 14-kDa fusion protein of vaccinia and variola virus, and between the 34-kDa MCV protein and the 37.5-kDa viral membrane-associated protein of vaccinia and variola virus. Rabbit antisera against these two proteins were prepared. An immunofluorescence study demonstrated that the 70- and 34-kDa proteins were predominantly expressed on the surface of recombinant virus-infected HeLa cells, indicating the potential to be inserted into the membrane. On immunoelectron microscopy, antiserum against 70-kDa protein showed significant labeling of the MCV membrane, while the antiserum against 34-kDa protein failed to do so.

Expression of keratohyalin-trichohyalin hybrid granules in molluscum contagiosum.

BACKGROUND: Recently, in the filiform papillae epithelium of mouse dorsal tongue, we showed the presence of hybrid granules in which filaggrin and trichohyalin were both present, but physically segregated. Further, trichohyalin was also detected in scattered granular cells of a number of hyperplastic skin diseases. METHODS: The epidermis infected with molluscum contagiosum virus (MCV) was studied by conventional electron microscopy in conjunction with light and electron-microscopic immunohistochemistry, using both antifilaggrin and antitrichohyalin antibodies as probes. RESULTS: We found that the granular cells of MCV-infected epidermis contained both filaggrin and trichohyalin. Subsequent electron-microscopic examination showed that the granular cells contained morphologically heterogeneous granules that appeared to be composed of discrete areas of distinct electron densities. Double-labeling, using antibodies to filaggrin and trichohyalin, clearly indicated that filaggrin and trichohyalin were both present in the hybrid granules and that the electron-dense regions contained trichohyalin while the more electron-lucent regions contained filaggrin. CONCLUSIONS: The expression of trichohyalin was a common feature observed in the epidermis from a heterogenous group of hyperplastic conditions, including MCV infection. This finding has led us to speculate that trichohyalin may be specifically or preferentially involved in interacting with the hyperproliferation-related keratin pair (K6/K16), whereas the function of filaggrin is more closely linked to the skin-type keratin pair (K1/K10) that are normal keratins found in the differentiated epidermis.

Multiple giant molluscum contagiosa with cyst formation.

We report a case of multiple cystic tumors distributed on the scalp, face, neck, and upper trunk of a 68-year-old male. In all five cysts examined, the presence of molluscum contagiosum virus (MCV) was demonstrated electron microscopically, and the typical histological features of MCV infection were observed in the cyst wall. In one lesion, histological features suggesting a follicular origin of the cyst were seen.

[Chronic unilateral keratoconjunctivitis in molluscum contagiosum of the upper eyelid margin]. / Chronische einseitige Keratokonjunktivitis bei Molluscum contagiosum der Oberlidkante.

PATIENT AND METHODS: Over a period of one year a 33-year-old married housewife, mother of two healthy children, complained of an initially recurrent, in the last 6 months persisting conjunctivitis, upper and lower lid edema, dacryorrhea and photophobia concerning the left eye. Neither topical derivates of cromoglycin acid, antibiotics nor steroids brought relief. Half a year ago the patient had noticed a "little nodule" of the lateral upper eyelid without tendency to grow. The visual acuity was 0.8 due to a punctate superficial keratopathy. In addition a marked follicular conjunctivitis was present. Our examination revealed a little whitish-rosy tumor with elevated edges and a central crater at the lateral margin of the upper lid. The right eye was completely normal. The tumor was totally excised preserving the lid margin. Our histopathological diagnosis was "molluscum contagiosum". Four weeks after surgery the keratoconjunctivitis had subsided without further medication. CONCLUSION: In persisting unilateral conjunctivitis without amelioration after any topical therapy the eyelids should be checked carefully for a tumor to be excised. In older patients a sebaceous gland carcinoma must be ruled out. Considering the patient's personal history a chlamydial infection should be kept in mind as a differential diagnosis.

Three-dimensional ultrastructural study of molluscum contagiosum in the skin using scanning-electron microscopy.

The three-dimensional ultrastructure of molluscum contagiosum virus (MCV) in human skin was visualized using scanning-electron microscopy with the osmium-dimethyl sulphoxide-osmium method. There were spherical, ellipsoidal, brick-shaped, miniature and incomplete forms of MCV. In all the forms the surface had densely distributed small protrusions and all had the same ultrastructure. All the forms had one or two long cord-like substances that appeared to be linked together, but became short, vestigial or absent on the surface of the mature virus. The cord-like substances were connected to the core of the MCV. In the matrix between the viruses, the cord-like substances formed an intricate fine network.

Molluscum contagiosum associated with AIDS: a case report with ultrastructural study.

The clinical features of perioral molluscum contagiosum in a patient with the acquired immunodeficiency syndrome are described. Light microscopy and thin section electron microscopy revealed epidermal cells in different stages of degeneration showing two types of cytoplasmic inclusions. The basement membrane exhibited discontinuities and multiple laminations which may be a response to viral-induced cytotoxic effects.

Molluscum contagiosum: serology and electron microscopy findings in twenty one patients

Vinte e um casos de molusco contagioso foram escolhidos para serem analisados por testes sorológicos e de microscopia eletrônica. O vírus do molusco foi detectado nas crostas e observados também nos vacúolos formados dentro dos queratinócitos. Os pacientes desenvolveram anticorpos fixadores do complemento para o vírus

Demonstration of a unique viral structure: the molluscum viral colony sac.

Using scanning electron microscopy to study molluscum contagiosum lesions, it has been possible to demonstrate a unique, well defined sac enclosing the virion colony of each infected keratinocyte. This confirms the presence of a structure demonstrated over 50 years ago by micro-dissection, but ignored since it is not seen on either light or transmission electron microscopy. It is postulated that this sac, of unknown origin, favours replication of the virions by providing a site that is both anatomically and immunologically privileged. Such relatively unimpeded growth of the virions results in an enlarged cell in which the cytoplasm and nucleus are compressed into a thin outer shell. In the aggregate, this produces a tumour of virus-packed cells rather than a tumour composed of virus-induced cell hyperplasia.

[Annulate nexus and "virus like particles" (author's transl)]. / Ringnexusbildungen und "virus like particles".

Dependent on the direction in which the specimens are sectioned annular shaped nexus of neighbouring cell membranes may be misinterpreted as "virus like particles". It is suggested that many of the "virus like particles" described in tumor research may be annulate nexus.