Molluscum contagiosum: histologic patterns and associated lesions. A study of 578 cases

Pockenvirusinfektionen in der Dermatologie: Poxvirus infections in dermatology - the neglected, the notable, and the notorious

Die Familie Poxviridae umfasst derzeit 22 Gattungen, die Wirbeltiere infizieren können. Humanpathogene Pockenviren gehören den Gattungen Ortho‐, Para‐, Mollusci‐ und Yatapoxvirus an. Bis zur Eradikation der Variola vera im Jahr 1979 waren die Pocken, im Volksmund auch Blattern genannt, eine schwerwiegende Gesundheitsbedrohung für die Bevölkerung. Noch heute sind Dermatologen mit zahlreichen Pockenvirusinfektionen konfrontiert, wie den Bauernhofpocken, die als Zoonosen nach Tierkontakten in ländlichen Gebieten oder nach Massenversammlungen auftreten können. In den Tropen können Erkrankungen durch Tanapox‐ oder Vaccinia‐Viren zu den Differenzialdiagnosen gehören. Dellwarzen sind weltweit verbreitet und werden in bestimmten Fällen als sexuell übertragbare Pockenvirusinfektion angesehen. In jüngster Zeit hatten sich Mpox (Affenpocken) zu einer gesundheitlichen Notlage von internationaler Tragweite entwickelt, die eine rasche Identifizierung und angemessene Behandlung durch Dermatologen und Infektiologen erfordert. Fortschritte und neue Erkenntnisse über Epidemiologie, Diagnose, klinische Manifestationen und Komplikationen sowie Behandlung und Prävention von Pockenvirusinfektionen erfordern ein hohes Maß an Fachwissen und interdisziplinärer Zusammenarbeit in den Bereichen Virologie, Infektiologie und Dermatologie. Dieser CME‐Artikel bietet einen aktualisierten systematischen Überblick, um praktizierende Dermatologen bei der Identifizierung, Differenzialdiagnose und Behandlung klinisch relevanter Pockenvirusinfektionen zu unterstützen.

Poxvirus infections in dermatology - the neglected, the notable, and the notorious

The family Poxviridae currently comprises 22 genera that infect vertebrates. Of these, members of the Ortho-, Para-, Mollusci- and Yatapoxvirus genera have been associated with human diseases of high clinical relevance in dermatology. Historically, smallpox had been a notorious health threat until it was declared eradicated by the World Health Organization in 1979. Today, dermatologists are confronted with a variety of poxviral infections, such as farmyard pox, which occurs as a zoonotic infection after contact with animals. In the tropics, tanapox or vaccinia may be in the differential diagnosis as neglected tropical dermatoses. Molluscum contagiosum virus infection accounts for significant disease burden worldwide and is classified as a sexually transmitted infection in certain scenarios. Recently, mpox (monkeypox) has emerged as a public health emergency of international concern, requiring rapid recognition and appropriate management by dermatologists and infectious disease specialists. Advances and new insights into the epidemiology, diagnosis, clinical manifestations and complications, treatment, and prevention of poxviral infections require a high level of expertise and interdisciplinary skills from healthcare professionals linking virology, infectious diseases, and dermatology. This CME article provides a systematic overview and update to assist the practicing dermatologist in the identification, differential diagnosis, and management of poxviral infections.

Molluscum contagiosum presenting as periorbital abscess in immunocompetent children

Molluscum contagiosum presenting as a periorbital region abscess is unusual. The virus generally causes a self-limiting localized disease in children. Presentation as an abscess has been reported mainly in immunocompromised patients. We performed a retrospective study of ten children treated for Molluscum contagiosum infection presenting as periorbital abscess. Data investigated included age, immunocompetence, systemic antibiotic treatment, clinical findings, and histopathology. All children were immunocompetent. Bacterial cultures taken in six of the ten children were positive in two. Seven patients received oral antibiotics before presentation but required IV antibiotics on admission. One patient received IV antibiotics only. All antibiotic treatment had very limited effect. Two patients had no antibiotic treatment. CT imaging in one case where orbital cellulitis was suspected showed no significant intraorbital findings with anterior involvement only. Nine out of ten children had surgery and intra-operative cryotherapy at our center with immediate improvement and recovery. One child whose parents initially refused surgical excision had initial limited clinical improvement of periorbital swelling with antibiotics. However, the lesions were excised shortly following discharge from our hospital at another medical center with a complete cure. Molluscum is a cause of periorbital abscess in immunocompetent children which should be part of the differential diagnosis in periorbital/adnexal infection. Antibiotic treatment has a limited effect, and the abscess is most likely a virally triggered reaction. Surgical excision and intra-operative cryotherapy are curative of the disease in our experience.

Clinical Conundrums: Differentiating Monkeypox From Similarly Presenting Infections

Post the coronavirus disease 2019 (COVID-19) pandemic, there arises the concern of a new epidemic as cases of monkeypox are being confirmed, globally. With the initial clinical manifestation of monkeypox resembling that of the common cold or seasonal flu, recognizing alternative differential diagnoses is imperative as a medical health practitioner. The characteristic monkeypox maculopapular rash with the progression to vesicles and pustules before scabbing can be described in several other infections. Understanding the disease progression and distinct clinical presentation of monkeypox in its various stages may allow for a more expedient diagnosis among healthcare providers. Though eradicated, the clinical presentation of smallpox is the most similar to that of monkeypox; however, smallpox is no longer a concern for the general population. Other conditions such as molluscum contagiosum, syphilis, varicella zoster, measles, rickettsialpox, and scabies can present with rashes that may resemble singular or multiple states of the monkeypox rash progression. The ability to correctly diagnose an individual's condition promptly may allow healthcare providers to provide correct supportive therapies or treatments.

British Association for Sexual Health and HIV national guideline for the management of Genital Molluscum in adults (2021)

This guideline offers recommendations on diagnosis, treatment regimens and health promotion principles needed for the effective management of genital molluscum, including management of the initial presentation and recurrences. The Primary focus of the guideline is on infection which affects the genital area and has a sexual mode of transmission. This is an update to the guideline previously published in this journal in 2014.

2020 European guideline on the management of genital molluscum contagiosum

Molluscum contagiosum is a benign viral epidermal infection associated with high risk of transmission. The guideline is focused on the sexually transmitted molluscum contagiosum. The diagnosis is clinical with characteristic individual lesions, termed 'mollusca', seen as dome-shaped, smooth-surfaced, pearly, firm, skin-coloured, pink, yellow or white papules, 2 - 5 mm in diameter with central umbilication. Dermoscopy may facilitate diagnosis. Therapeutic options are numerous, including physical treatments (cautery, curettage and cryotherapy), topical chemical treatments (e.g. podophyllotoxin and imiquimod) or waiting for spontaneous resolution in immunocompetent patients. In pregnancy, it is safe to use physical procedures (e.g. cryotherapy). Immunosuppressed patients develop severe and recalcitrant molluscum lesions that may require treatment with cidofovir, imiquimod or interferon. Patients with molluscum contagiosum infection should be offered to be screened for other sexually transmitted infections.

[Relevance of biopsies for the diagnostics of infectious skin diseases]

Pathogen-related skin infections are a common problem in the dermatological practice. Apart from culturing and serological detection methods, a skin biopsy is a possible diagnostic procedure, especially when the clinical picture is unspecific and other non-infectious skin diseases are considered as possible differential diagnoses. Some organisms can already be detected by routine staining methods (hematoxylin & eosin, e. g., yeasts, Leishmania), for others numerous histochemical and immunohistochemical stains are available, e. g. periodic acid-Schiff reaction (PAS) and Grocott for hyphae and spores, Ziehl-Neelson and Fite-Faraco for Mycobacteria or specific antibodies for Treponema pallidum or herpesviruses. In other instances, an infectious disease may not be diagnosed with certainty in a histological section but the pattern of inflammatory infiltrates is highly suggestive of an infectious cause. Based on such reaction patterns, the dermatopathologist can advise the clinician to perform cultures or serological investigations or additional molecular biological techniques can be applied to the biopsy specimen in order to identify the pathogens. This article presents skin infections with their histopathological features and highlights diseases that can be diagnosed with certainty in a biopsy and those in which a biopsy is helpful to exclude differential diagnoses or to perform molecular diagnostics on the specimen.

[Human poxvirus infections]

Poxvirus (PXV) infections are a common cause of cutaneous signs. In France, certain forms of poxvirus are frequent and benign (molluscum contagiosum), while others are rare but potentially serious (cowpox virus [CPXV]). Whereas only smallpox and molluscum contagiosum viruses have a human reservoir and are transmitted between humans, most poxvirus infections are zoonoses having only animal reservoirs. Only a small number of poxviruses are responsible for infection in humans, but the increasing number of new pets, some of which are exotic, coupled with the rapid rise in international travel are creating a greater risk of transmission of zoonotic PXV to new vectors and of spread of these diseases to new regions throughout the world. In France, molluscum contagiosum, orf and milkers' nodule give rise to numerous consultations and are well known to dermatologists. However, dermatologists must also be able to identify other parapoxviruses of similar presentation to orf; thus, CPXV and monkeypox are considered potentially emergent viruses with a high risk of epidemic and spread due to increasing international transport and the loss of the maximum protection against smallpox. Finally, despite its declared eradication, smallpox is currently being monitored because of the potential risk of reintroduction, whether accidentally or deliberately through bioterrorism.

Molluscum contagiosum arising in a melanocytic congenital nevus

Molluscum contagiosum within a congenital melanocytic nevus has rarely been reported. We report a 6-year-old child with molluscum contagiosum infection arising within an intermediate melanocytic congenital nevus of the thigh, associated with itching and occasional bleeding. Dermoscopy lead to the correct diagnosis, but histologic confirmation with shave biopsy was performed to reassure the parents and allow mechanical removal of the lesions using curettage.

Primitive follicular induction in molluscum contagiosum

BACKGROUND

Molluscum contagiosum (MC) is the commonest human poxvirus infection. Follicular induction has rarely been observed in the epidermis surrounding lesions of MC. A virus-induced localized proliferation of germinative/stem cells of the folliculosebaceous-apocrine unit has been suggested as the underlying cause, however few reports of this peculiar phenomenon exist in the literature and the mechanisms involved in this proliferation require further study.

METHODS

We prospectively collected MC cases showing multifocal areas of primitive follicular induction involving the adjacent undersurface epidermis. Immunohistochemical expression of BerEP4, PHLDA1 and cytokeratin 20 (CK20) was evaluated in the basaloid germs surrounding the lesions. For PHLDA1, we used epidermal melanocytes as a positive internal control. For BerEP4, we employed a basal cell carcinoma (BCC) and for CK20, colon as positive external controls. An incubation without the primary antibody functioned as an external negative control.

RESULTS

All the cases studied showed an intense positive staining of the basaloid buds with BerEP4 and weaker stain for PHLDA1. CK20 showed the presence of scattered Merkel cells within the induced epidermal basaloid proliferations favoring their reactive origin.

DISCUSSION

The pathogenetic mechanisms behind the development of these microscopic features and the link between follicular induction and poxvirus infection are explored. Awareness of this unusual phenomenon by dermatopathologists will be helpful in avoiding a misdiagnosis of a superficial BCC in such cases.

CONCLUSIONS

BerEP4 and PHLDA1 were consistently expressed in the areas of primitive follicular induction surrounding lesions of MC. CK 20 stained the Merkel cells present in the basaloid buds. All these findings support the reactive origin of this phenomenon, which we believe is most probably viral-induced.

Immune evasion strategies of molluscum contagiosum virus

Molluscum contagiosum virus (MCV) is the causative agent of molluscum contagiosum (MC), the third most common viral skin infection in children, and one of the five most prevalent skin diseases worldwide. No FDA-approved treatments, vaccines, or commercially available rapid diagnostics for MCV are available. This review discusses several aspects of this medically important virus including: physical properties of MCV, MCV pathogenesis, MCV replication, and immune responses to MCV infection. Sequencing of the MCV genome revealed novel immune evasion molecules which are highlighted here. Special attention is given to the MCV MC159 and MC160 proteins. These proteins are FLIPs with homologs in gamma herpesviruses and in the cell. They are of great interest because each protein regulates apoptosis, NF-κB, and IRF3. However, the mechanism that each protein uses to impart its effects is different. It is important to elucidate how MCV inhibits immune responses; this knowledge contributes to our understanding of viral pathogenesis and also provides new insights into how the immune system neutralizes virus infections.

Molluscum contagiosum virus: persistence pays off

The molluscum contagiosum (MC) virus (MCV) is a dermatotropic poxvirus, and the causative agent of MC. Unlike smallpox and human monkeypox diseases, MC is nonlethal, common and worldwide. Additionally, little inflammation is associated with MC papules, and MC can persist for months to years. Such a prolonged infection implies that MCV successfully manipulates the host environment. This review highlights recent findings that reveal how MCV infections manipulate localized host immune responses and which immune response are key for the eventual resolution of MC. Also highlighted here are the MCV proteins that inhibit apoptosis, inflammation and immune cell recruitment or that induce cellular proliferation, with discussion as to how these proteins dampen localized antiviral immune responses. Lastly, this review discusses how the immune evasion tactics of MCV have led to insights about specific functions of the human innate and adaptive immune responses.

Follicular induction in a case of molluscum contagiosum: possible link with secondary anetoderma-like changes?

Molluscum contagiosum (MC) can rarely show follicular neogenesis as a result of proliferation of virus-infected basal cells. We report a case of molluscum contagiosum showing multifocal areas of primitive follicular induction involving the adjacent surface epidermis. The underlying dermis showed histological features suggestive of secondary anetoderma. The pathogenetic mechanisms behind development of these microscopic features and the putative link between follicular induction and secondary anetoderma are explored. Awareness of this unusual phenomenon will be helpful in avoiding a misdiagnosis of a superficial basal cell (trichoblastic) carcinoma in such cases.

Kaposi sarcoma in association with molluscum contagiosum: an uncommon diagnosis in a single biopsy and potential diagnostic pitfall

Molluscum contagiosum is a cutaneous poxviral infection that is rarely associated with other skin diseases, such as cutaneous neoplasms. Such associations are likely to be coincidental, except in immunocompromised patients. Kaposi sarcoma, an angioproliferative neoplasm derived from lymphatic endothelium, is mediated by human herpes virus-8 infection and occurs with increased frequency in immunocompromised individuals. We report an unusual case of molluscum contagiosum with underlying cutaneous Kaposi sarcoma diagnosed in a single skin biopsy of a human immunodeficiency virus-positive patient. Our case highlights the importance of adequate sampling to avoid missing secondary diagnoses in histopathologic sections and alerts pathologists and dermatologists to the possibility of coinfection in high-risk patients by 2 virally-mediated skin conditions.

Recognition of Dual or Multiple Pathology in Skin Biopsies from Patients with HIV/AIDS

A large percentage of patients with HIV/AIDS will develop dermatological complications. Consequently, all practising clinicians and pathologists in regions with a high prevalence of HIV/AIDS must be familiar with the diverse cutaneous manifestations of the disease. This paper highlights the fact that biopsy material in this clinical context may occasionally reveal more than one pathological process. The potential spectrum includes two or more infections in a single skin biopsy (e.g., herpes simplex and cytomegalovirus infection), neoplastic lesions containing infective organisms (Kaposi sarcoma (KS) and cryptococcosis), dermatoses in association with neoplastic lesions (e.g., KS and interface dermatitis), or more than one dermatosis in a given specimen (e.g., papulopruritic eruption and nodular prurigo). Rare biopsies may even demonstrate triple pathology. The importance of careful examination of skin biopsies in this clinical context is emphasised. Failure to recognise an undiagnosed concomitant opportunistic infective pathogen could have potentially disastrous consequences for the patient.

The cytology of molluscum contagiosum mimicking skin adnexal tumor

Molluscum contagiosum is a cutaneous viral infection presenting as multiple, umbilicated papules and vesicles. The cytology of molluscum contagiosum in an 11-year-old boy, which presented atypically as a solitary nodule over the right cheek, mimicking a skin adnexal tumor is reported here. Fine needle aspiration cytology plays a vital role in establishing the correct diagnosis of clinically unsuspected cases, and hence, the proper management of such lesions. The cytology of molluscum contagiosum is characterized by the presence of numerous large intracytoplasmic basophilic bodies that push the host nucleus to the periphery, giving a signet ring appearance to the superficial epidermal cells.

Spontaneous regression of highly immunogenic Molluscum contagiosum virus (MCV)-induced skin lesions is associated with plasmacytoid dendritic cells and IFN-DC infiltration

Molluscum contagiosum virus (MCV) infection induces self-limiting cutaneous lesions in an immunocompetent host that can undergo spontaneous regression preceded by local inflammation. On histology, a large majority of MCV-induced lesions are characterized by islands of hyperplastic epithelium containing infected keratinocytes and surrounded by scarce inflammatory infiltrate. However, spontaneous regression has been associated with the occurrence of a dense inflammatory reaction. By histology and immunohistochemistry, we identified MCV-induced lesions showing a dense inflammatory infiltrate associated with cell death in keratinocytes (inflammatory Molluscum contagiosum (I-MC)). In I-MC, hyperplastic keratinocytes were highly immunogenic as demonstrated by the expression of major histocompatibility complex class I and II molecules. Immune cell infiltration consisted of numerous cytotoxic T cells admixed with natural killer cells and plasmacytoid dendritic cells (PDCs). Accordingly, a type I IFN signature associated with PDC infiltration was demonstrated in both keratinocytes and inflammatory cells. Among the latter, a cell population resembling IFN-DC (CD123(+)CD11c(+)CD16(+)CD14(+)MxA(+)) was identified in proximity to islands of apoptotic keratinocytes. In vitro-generated IFN-DCs expressed a strong cytotoxic signature, as demonstrated by high levels of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and Fas ligand (FasL). This study establishes a previously unreported model to underpin the role of innate immune cells in viral immune surveillance.

Dermatopathological challenges in the human immunodeficiency virus and acquired immunodeficiency syndrome era

The histopathological assessment of cutaneous lesions is critical to the definitive diagnosis of many human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome-associated dermatoses, infections and tumours. Dermatopathological challenges stem mainly from the altered histopathological profile of established cutaneous entities compared with that in the HIV-unaffected population, the emergence of new diseases and the impact of therapeutic modalities on cutaneous lesions. This review focuses on some of these diagnostic dilemmas, with emphasis on the following challenges: (i) infective diagnostic pitfalls; (ii) itchy papular skin lesions; (iii) co-lesional comorbid diseases; (iv) drug-induced disease alterations; and (v) neoplastic and pseudoneoplastic proliferations. The drug-induced alterations include highly active antiretroviral therapy-associated disease modifications.

Granulomas in acquired immunodeficiency syndrome-associated cutaneous Kaposi sarcoma: evidence for a role for Mycobacterium tuberculosis

BACKGROUND

Co-lesional acquired immunodeficiency syndrome-associated cutaneous Kaposi sarcoma (AIDS-KS) and Mycobacterium tuberculosis-associated granulomatous inflammation are undocumented.

METHOD

Retrospective appraisal of skin biopsies with co-lesional AIDS-KS and microscopic tuberculosis (TB).

RESULTS

Sixteen biopsies from nine males and seven females form the study cohort. Histological assessment confirmed nodular and plaque KS in 12 and 4 cases each, respectively. Necrotizing, non-necrotizing and a combination of necrotizing and non-necrotizing granulomatous inflammation were present in nine, two and five biopsies each, respectively. The identification of acid fast bacilli on Ziehl-Neelsen staining and M. tuberculosis on polymerase chain reaction confirmed co-lesional TB in 15/16 biopsies. Co-lesional AIDS-KS and lichen scrofulosorum, hitherto undocumented, were confirmed in one biopsy. The histopathological findings served as a marker of human immunodeficiency virus (HIV) infection, visceral TB, therapeutic noncompliance and multidrug resistant pulmonary TB in nine, eight, five and one patient, respectively. M. tuberculosis was cultured from sputum or nodal tissue of all patients.

CONCLUSION

Granulomatous inflammation in KS requires optimal histopathological and molecular investigation to confirm an M. tuberculosis origin. The cutaneous co-lesional occurrence of AIDS-KS and microscopic TB may serve as the sentinel clue to HIV infection, systemic TB, therapeutic noncompliance or multidrug resistant TB.

Molluscum contagiosum arising in melanocytic nevus and in superficial spreading melanoma

Molluscum contagiosum (MC) is common skin infection caused by molluscum virus. Growth of MC inside melanocytic lesion is extremely rare. We present the case of MC in common melanocytic nevus and the first case of MC in superficial spreading malignant melanoma. Complete destruction of melanocytes and melanoma cells occurred on the site of MC infection. MC virus might be considered as a future candidate for viral oncolysis in cutaneous melanoma patients with advanced disease.

The epidemiology of Molluscum contagiosum in HIV-seropositive patients: a unique entity or insignificant finding?

Molluscum contagiosum (MC) is common in human immunodeficiency virus (HIV) seropositive and immunocompromised patients. This study evaluates the current literature concerning the clinical features of MC in this population, the utility of MC as a predictor of immunocompromised state and the natural history of MC and HIV in patients with these co-morbidities. PubMed database search for English-written original studies found 10 of them, all enrolled for HIV patients. There was no unique feature of MC in adult HIV patients; nevertheless, the appearance of MC lesions in adult men should require evaluation for immunocompromised state. In HIV-positive patients, MC tends to occur during the advanced phase of the disease. MC in children is rarely associated with immunodeficiency and usually no further evaluation is needed. In patients with known HIV infection, the presence of MC may signify advancing immunosuppression.

Purple penile papules

Molluscum contagiosum may present in a variety of clinical and pathologic guises. We present the clinicopathologic features of an unusual case that initially was misinterpreted as bowenoid papulosis. The relevant histologic attributes of this case include the presence of a violaceous hyperplastic squamous epithelium adjacent to the infected keratinocytes. The presence of this violaceous cytoplasmic staining should prompt a search for molluscum in the appropriate clinical context.

Ocular manifestations of molluscum contagiosum

PURPOSE

Two cases of molluscum contagiosum (MC) are presented to illustrate the range of potential anterior segment complications of this condition.

METHODS

Clinical records for two patients diagnosed with MC are retrospectively reviewed. Diagnosis and management of both cases are presented.

RESULTS

The first patient demonstrates a classic presentation of ocular MC. The patient was young and had several dermal lid lesions at the time of presentation. The second case represents a less common presentation. The patient was an adult and had a single lid lesion that was not apparent at the initial examination. Both patients had follicular conjunctivitis that resolved with excision of the concomitant eyelid lesions.

CONCLUSION

MC is a treatable cause of chronic conjunctivitis or keratoconjunctivitis. Eye-care providers should be mindful that MC could present as a follicular keratoconjunctivitis with or without obvious dermal lid lesions. The possibility of immuno-compromise must be considered in patients with multiple large lesions, cutaneous lesions that do not respond to standard therapy, or recurrent lesions.

Clinicopathological and Ultrastructural Study of Multiple Lobular Capillary Hemangioma after Scalding

We herein report 2 cases of multiple lobular capillary hemangiomas after scalding. The patients exhibited papules and nodules on the scalded areas after healing. Histopathological examination of the lesions showed capillary proliferation in the upper dermis with edematous stroma containing inflammatory infiltrates predominantly composed of neutrophils. Biopsy tissue and secretion specimens from lesions of case 1 were cultured for bacteria, and both grew Enterobacter cloacae. Ultrastructural examination revealed features typical of a lobular capillary hemangioma and viral inclusion bodies in the epidermis of case 1. Multiple lobular capillary hemangiomas after scalding are rarely reported. Trauma may play an important role in the development of this rare condition. Accumulation of similar cases and its precise observation is needed to confirm the associations and to establish an etiological link between the disease and the pathogens.

[Nevocytic nevi associated elastic fibers hyperplasia: a type of "twin nevus"]

BACKGROUND

In common intradermal or compound nevi, nevocytes may be associated with other kinds of cells, tissues or lesions. In rare cases, they are associated with notable hyperplasia of the elastic fibers. CASE-REPORTS AND RESULTS: In 11 nevi (10 intradermal or compound nevi and 1 blue nevus), we observed striking hyperplasia of the elastic fibers strictly limited to the nevi, with normal aspect of the elastic fibers in the surrounding reticular dermis. These fibers were thicker than normal elastic fibers and showed tight connexions with nevus cells. This hyperplasia was not clinically relevant. It was correlated neither with the age and sex of patients nor with the site of the excised nevi. It was seen in 0.1% of excised nevi.

DISCUSSION

Hyperplasia of elastic fibers in some common nevi is a curiosity which may be classified together with other vascular, nervous, epithelial or connective twin lesions occasionally associated with the nevocytic nevi. It has to be added to the list of so-called "twin nevi".

Cutaneous malignancy and human immunodeficiency virus disease

Certain skin cancers occur with increased frequency or altered course in patients infected with HIV. Malignant melanoma and squamous cell carcinoma are examples of cutaneous malignancies that have a more aggressive course in patients with HIV. Others, such as basal cell carcinoma, appear more frequently in this population but do not appear to be more aggressive. The incidence of HIV-associated Kapsosi's sarcoma has markedly decreased since the advent of HIV antiretroviral therapy. Our understanding of the pathogenesis of this malignancy and its unique management issues are fully reviewed. Cutaneous T-cell lymphoma (CTCL) is rare in this population. Other types of cutaneous lymphoma and HIV-associated pseudo-CTCL are discussed. This article addresses prevention, treatment, and follow-up strategies for this at-risk population.

LEARNING OBJECTIVE

At the completion of this learning activity, participants should be familiar with the unique epidemiology, clinical course, and management of cutaneous malignancy in patients infected with HIV.

The epidemiology of molluscum contagiosum in children

Molluscum contagiosum (MC) is a viral disorder of the skin and mucous membranes characterized by discrete single or multiple, flesh-colored papules. Although MC as a clinical entity is well defined and commonly observed, few data regarding its epidemiology in the pediatric population exist. Our purpose was to collect epidemiologic data on children with MC with regard to age, gender, ethnicity, degree of involvement, relation to pre-existing atopic dermatitis (AD), and immune status. A retrospective chart review was conducted. All subjects were seen at 3 tertiary pediatric dermatology referral centers with two of the sites based at a Children's Hospital. A total of 302 patient charts with the Current Procedural Terminology code diagnosis of MC seen over a 6- to 8-month period were reviewed. Approximately 80% of the patients were younger than 8 years old. The majority of patients (63%) had more than 15 lesions. All but one patient were otherwise healthy, as determined by history and clinical examination. Approximately 24% of the patients presented with a history of previous or active coexistent AD. However, children with AD were at risk for an increased number of lesions. These data provide valuable updated information on the demographics and clinical presentation of MC in pediatric patients in the United States. Limitations include that this was a retrospective study with a population limited to tertiary pediatric dermatology referral centers.

Multiple giant molluscum contagiosum in a renal transplant recipient

Atypical presentations of molluscum contagiosum (MC) infection can be expected in renal transplant recipients, as a result of long-term immunosuppression. However, giant MC has rarely been reported in this population. We present a 28-year-old female renal transplant recipient receiving immunosuppressive therapy who developed multiple giant MC lesions on her axillary folds. The lesions were treated successfully with curettage and electrocauterization.

Pediatric molluscum contagiosum: optimal treatment strategies

Pediatric molluscum contagiosum virus (MCV) is a common pox viridae infection that represents a common public health issue. The spread of the virus among children is rapid and easy. The virus produces a number of substances that block immune response formation in the infected host. Despite the benign and self-limited nature of the condition, one-third of children have symptoms from, or secondary reactions to the infection, including pruritus, erythema and, occasionally, inflammation and pain. Patients with pruritus autoinoculate the virus through scratching, thereby exacerbating their conditions. While adults cope well with unanesthetized curettage of lesions, children require less painful therapeutic options. The options for therapy are manifold. Therapy should begin with gentle skin care and antipruritics to prevent symptoms, and to prevent the spread of the disease. Therapies with good efficacy and low risk of pain for the patient include in-office usage of cantharidin and the use of local anesthetics, such as topical lidocaine (lignocaine) preparations in combination with the curettage of visible lesions. Alternatively, cryosurgery can be performed to eradicate lesions in-office. At-home therapeutics are often preferred by parents and children, and include imiquimod, retinoids, and alpha-hydroxy acids. Although a variety of such at-home therapies are available, none are as effective or as rapid acting as in-office therapy. Further research in large clinical trials is required to increase knowledge on prevention, optimal treatment, and long-term outcome with this disease.

Cutaneous pseudolymphoma in association with molluscum contagiosum in an elderly patient

BACKGROUND

Molluscum contagiosum (MC) is a common cutaneous infection, which has been reported in association with cutaneous pseudolymphoma in few cases.

METHODS

A 72-year-old woman with a nodule arising on the external canthus was reviewed. The lesion was surgically removed, and the histopathological study demonstrated an epidermal invagination filled by molluscum bodies and a diffuse infiltrate comprising atypical lymphocytes.

RESULTS

Immunohistochemical stains disclosed predominance of T cells with positive CD30 labeling. Polymerase chain reaction failed to demonstrate clonal rearrangement of the T-cell receptor.

CONCLUSION

After ruling out systemic involvement, the patient was followed up for 2 years with no evidence of recurrence. We report this case to the best of our knowledge and discuss the literature about atypical clinical and histological presentations of MC.

Trichofolliculoma of the vulva associated with vulvar intraepithelial neoplasia: report of three cases and review of the literature

Trichofolliculoma is an uncommon, benign cutaneous adnexal neoplasm most commonly occurring on the head and neck. Trichofolliculoma of the vulva has not been previously reported. The juxtaposition of a trichofolliculoma in an excisional biopsy specimen performed for vulvar intraepithelial neoplasia (VIN III) created a diagnostic dilemma and prompted a review of our files from 1989 to 2000 for additional cases. A search for benign hair follicle tumors of the vulva identified two additional trichofolliculomas. All three vulvar trichofolliculomas were associated with VIN III. During this same period, 628 cases of vulvar intraepithelial neoplasia II and III were identified. The appearance of trichofolliculoma at this previously unreported site may present diagnostic difficulty.