Viral infections and inborn errors of immunity.

PURPOSE OF REVIEW: The purpose of this focused review is to discuss unusual presentations of viral infections in the context of specific inborn errors of immunity. We will discuss hyper immunoglobulin E (IgE) syndromes, epidermodysplasia verruciformis, and X-linked agammaglobulinemia as examples of inborn errors of immunity associated with specific presentations of viral infection and disease. RECENT FINDINGS: Advances in both genetic and viral diagnostics have broadened our understanding of viral pathogenesis in the setting of immune dysfunction and the variable phenotype of inborn errors of immunity. Dedicator of cytokinesis 8 (DOCK8) deficiency is now recognized as an inborn error of immunity within the hyper IgE syndrome phenotype and is associated with unusually aggressive cutaneous disease caused by herpes simplex and other viruses. Studies of patients with epidermodysplasia verruciformis have proven that rarely detected human papillomavirus subtypes may cause malignancy in the absence of adequate host defenses. Finally, patients with X-linked agammaglobulinemia may remain at risk for severe and chronic viral infections, even as immune globulin supplementation reduces the risk of bacterial infection. SUMMARY: Susceptibility to viral infections in patients with inborn errors of immunity is conferred by specific, molecular defects. Recurrent, severe, or otherwise unusual presentations of viral disease should prompt investigation for an underlying genetic defect.

Epidermodysplasia Verruciformis After Hematopoietic Stem Cell Transplantation in a Patient With Severe Combined Immunodeficiency Syndrome.

ABSTRACT: Epidermodysplasia verruciformis (EV) is a rare dermatologic disorder that is characterized by skin-colored-to-light brown flat, discrete or confluent papules resembling verruca plana. EV is divided into 2 forms: a classical genetic form and an acquired form. Classical genetic EV is caused by mutations in EVER1 and EVER2 genes. Acquired EV develops in immunocompromised patients such as HIV-positive patients and transplant recipients. Patients with a prior history of hematopoietic stem cell transplantation (HSCT) have tendency to develop generalized verrucosis. We report an extraordinary case of disseminated epidermodysplasia verruciformis seen in a 7-year-old boy diagnosed with severe combined immunodeficiency syndrome who had undergone HSCT. He had plane, brown papules involving his face, forearms, neck, anterior chest, nape, back, and knees. Cutaneous biopsy showed typical characteristic findings of EV: large cells with gray-blue cytoplasm and keratohyaline granules of different sizes in the granular and spinous layers. Herein, we present an unusual case of disseminated EV in a HSCT patient with typical histopathologic findings and treatment options.

Acquired Epidermodysplasia Verruciformis in the Setting of Renal Transplant.

ABSTRACT: Epidermodysplasia verruciformis (EV) is a rare dermatologic condition that is clinically characterized by flat, cutaneous, verrucous papules, pityriasis versicolor-like lesions, and similar lichenoid papules. There are 2 forms of EV: a classic inherited genodermatosis and a secondary acquired form. EV predisposes individuals to infections with certain types of human papillomavirus virus and subsequently increases the risk of cutaneous squamous cell carcinoma. The acquired form occurs in immunosuppressed patients, particularly in patients infected with HIV; however, it has also been described in patients who have undergone stem cell and solid organ transplantation. We report an additional case of renal transplantation and immunosuppressive therapy-associated acquired EV (AEV) in a 78-year-old man with multiple flesh-colored to violaceous, flat-topped papules distributed on the face and trunk clinically mimicking lichen planus. Biopsy was typical for that of EV, demonstrating enlarged keratinocytes with a blue-gray cytoplasm, a thickened granular layer, acanthosis, and hyperkeratosis. Herein, we discuss an unusual presentation of an AEV-mimicking lichen planus with review of the literature.

Acquired Human Papilloma Virus Type 6-Associated Epidermodysplasia Verruciformis in a Patient With Systemic Lupus Erythematosus.

Although historically known as a genetic disorder, epidermodysplasia verruciformis (EV) might be acquired in patients with a noninherited defective cell-mediated immunity. This article reports a case of EV in a patient with systemic lupus erythematosus and a history of 3 years immunosuppressive methylprednisolone treatment. The microscopic features of the skin biopsy showed morphologic changes of the keratinocytes characteristic of human papilloma virus (HPV) infections and immunoreactivity to p16. HPV genotyping demonstrated the presence of HPV 6 which belongs to a low-risk mucosal HPV group and has not been reported in EV previously. The clinical recognition of EV in immunocompromised patients and subsequent HPV typing is important because some patients will develop squamous cell carcinoma.

Inherited Interleukin 2-Inducible T-Cell (ITK) Kinase Deficiency in Siblings With Epidermodysplasia Verruciformis and Hodgkin Lymphoma.

Biallelic mutations in the ITK gene cause a T-cell primary immunodeficiency with Epstein-Barr virus (EBV)-lymphoproliferative disorders. We describe a novel association of a homozygous ITK mutation with ß-human papillomavirus (HPV)-positive epidermodysplasia verruciformis. Thus, loss of function in ITK can result in broad dysregulation of T-cell responses to oncogenic viruses, including ß-HPV and EBV.

The human CIB1-EVER1-EVER2 complex governs keratinocyte-intrinsic immunity to ß-papillomaviruses.

Patients with epidermodysplasia verruciformis (EV) and biallelic null mutations of TMC6 (encoding EVER1) or TMC8 (EVER2) are selectively prone to disseminated skin lesions due to keratinocyte-tropic human ß-papillomaviruses (ß-HPVs), which lack E5 and E8. We describe EV patients homozygous for null mutations of the CIB1 gene encoding calcium- and integrin-binding protein-1 (CIB1). CIB1 is strongly expressed in the skin and cultured keratinocytes of controls but not in those of patients. CIB1 forms a complex with EVER1 and EVER2, and CIB1 proteins are not expressed in EVER1- or EVER2-deficient cells. The known functions of EVER1 and EVER2 in human keratinocytes are not dependent on CIB1, and CIB1 deficiency does not impair keratinocyte adhesion or migration. In keratinocytes, the CIB1 protein interacts with the HPV E5 and E8 proteins encoded by α-HPV16 and γ-HPV4, respectively, suggesting that this protein acts as a restriction factor against HPVs. Collectively, these findings suggest that the disruption of CIB1-EVER1-EVER2-dependent keratinocyte-intrinsic immunity underlies the selective susceptibility to ß-HPVs of EV patients.

Immunopathogenesis of HPV-Associated Cancers and Prospects for Immunotherapy.

Human papillomavirus (HPV) infection is a causative factor for various cancers of the anogenital region and oropharynx, and is supposed to play an important cofactor role for skin carcinogenesis. Evasion from immunosurveillance favors viral persistence. However, there is evidence that the mere presence of oncogenic HPV is not sufficient for malignant progression and that additional tumor-promoting steps are required. Recent studies have demonstrated that HPV-transformed cells actively promote chronic stromal inflammation and conspire with cells in the local microenvironment to promote carcinogenesis. This review highlights the complex interplay between HPV-infected cells and the local immune microenvironment during oncogenic HPV infection, persistence, and malignant progression, and discusses new prospects for diagnosis and immunotherapy of HPV-associated cancers.

Comparative study of p16 protein expression in squamous cell carcinomas from patients with epidermodysplasia verruciformis and patients without the disease.

Epidermodysplasia verruciformis (EV) is a rare genodermatosis associated with susceptibility to beta-human papilloma virus (HPV) infection. EV patients develop disseminated warts and non-melanoma skin cancer, mainly squamous cell carcinomas (SCC) that are locally aggressive. EV pathogenesis is not yet fully understood, but alterations in the p16 gene play a role in the pathogenesis of neoplasms caused by high-risk genital HPV. To explore its role in EV lesions, we compared p16 expression in SCC from patients with and without EV. Tissue microarray slides composed of 27 SCC from EV patients, and 35 from non-EV patients were stained with an anti-p16 antibody. Twenty (74%) EV tumors exhibited diffuse (nuclear and cytoplasmic) p16 expression, one (4%) displayed focal expression, and six (22%) displayed no p16 staining. Eleven (31%) SCC from non-EV patients presented diffuse p16 staining, 14 (40%) displayed focal expression and 10 (29%) did not express p16. The frequency of diffuse p16 expression was higher in EV tumors than in SCC from patients without EV. The frequency of diffuse p16 expression in moderately and poorly differentiated EV-SCC was similarly higher than non-EV tumors with the same degree of differentiation. The diffuse expression of p16 in EV-SCC suggests that changes in the p16 gene, probably resulting in a functionally defective protein, may be one factor determining the locally aggressive clinical behavior of SCC in young EV patients.

Re-evaluation of epidermodysplasia verruciformis: Reconciling more than 90 years of debate.

Epidermodysplasia verruciformis (EV) is a rare genodermatosis characterized by abnormal susceptibility to cutaneous human beta-papillomavirus infections causing persistent flat warts or pityriasis versicolor-like lesions. This generalized verrucous skin disorder resembles generalized verrucosis, but these 2 conditions are distinguished by differences in clinical manifestation and the human papillomavirus types involved. A breakthrough in our understanding of EV was the discovery that homozygous inactivating mutations in TMC6 (EVER1) and TMC8 (EVER2) determine susceptibility to this disorder; however, they have not solved all EV cases fully. These deficiencies account for 75% of affected individuals, leaving a substantial number of patients without an underlying genetic cause. Recently, it has been revealed that mutations in additional genes (RHOH, MST-1, CORO1A, and IL-7) result in extensive human beta-papillomavirus replication and therefore manifest with an EV-like phenotype. The term "acquired EV" is used to describe an EV-like phenotype that develops in immunocompromised hosts, and the introduction of this entity further aggravates the confusion. Reevaluation of these entities is warranted. Here, we review the available data on this issue, provide up to date information on the major characteristics that differentiate between these seemingly clinically similar disorders, and highlight the different mechanisms involved in each disorder.

The biology of beta human papillomaviruses.

The beta genus comprises more than 50 beta human papillomavirus (HPV) types that are suspected to be involved, together with ultraviolet (UV) irradiation, in the development of non-melanoma skin cancer (NMSC), the most common form of human cancer. Two members of the genus beta, HPV5 and HPV8, were first identified in patients with a genetic disorder, epidermodysplasia verruciformis (EV), that confers high susceptibility to beta HPV infection and NMSC development. The fact that organ transplant recipients (OTRs) with an impaired immune system have an elevated risk of NMSC raised the hypothesis that beta HPV types may also be involved in skin carcinogenesis in non-EV patients. Epidemiological studies have shown that serological and viral DNA markers are weakly, but significantly, associated with history of NMSC in OTRs and the general population. Functional studies on mucosal high-risk (HR) HPV types have clearly demonstrated that the products of two early genes, E6 and E7, are the main viral oncoproteins, which are able to deregulate events closely linked to transformation, such as cell cycle progression and apoptosis. Studies on a small number of beta HPV types have shown that their E6 and E7 oncoproteins also have the ability to interfere with the regulation of key pathways/events associated with cellular transformation. However, the initial functional data indicate that the molecular mechanisms leading to cellular transformation are different from those of mucosal HR HPV types. Beta HPV types may act only at early stages of carcinogenesis, by potentiating the deleterious effects of other carcinogens, such as UV radiation.

Severe infectious diseases of childhood as monogenic inborn errors of immunity.

This paper reviews the developments that have occurred in the field of human genetics of infectious diseases from the second half of the 20th century onward. In particular, it stresses and explains the importance of the recently described monogenic inborn errors of immunity underlying resistance or susceptibility to specific infections. The monogenic component of the genetic theory provides a plausible explanation for the occurrence of severe infectious diseases during primary infection. Over the last 20 y, increasing numbers of life-threatening infectious diseases striking otherwise healthy children, adolescents, and even young adults have been attributed to single-gene inborn errors of immunity. These studies were inspired by seminal but neglected findings in plant and animal infections. Infectious diseases typically manifest as sporadic traits because human genotypes often display incomplete penetrance (most genetically predisposed individuals remain healthy) and variable expressivity (different infections can be allelic at the same locus). Infectious diseases of childhood, once thought to be archetypal environmental diseases, actually may be among the most genetically determined conditions of mankind. This nascent and testable notion has interesting medical and biological implications.

Cornoid Lamella-Like Structures in HIV-Associated Epidermodysplasia Verruciformis: A Unique Histopathologic Finding.

Epidermodysplasia verruciformis (EV) is an uncommon inherited skin condition with increased vulnerability to widespread infection by certain human papillomavirus types, resulting in extensive verruca plana-like papules coalescing to large confluent plaques. Since the AIDS epidemic starting in the 1980s, an acquired type of EV has been described in patients infected with human immunodeficiency virus. The histopathologic features of EV consist of papillated epidermal hyperplasia with hypergranulosis and a distinct bluish-gray color in the large human papillomavirus-infected keratinocytes in the stratum granulosum. The authors present a case of HIV-associated EV with a unique histopathologic finding of multiple cornoid lamella-like structures. To the authors' knowledge, this finding has not been previously described in the literature.

Epidermodysplasia verruciformis: successful treatment with squaric acid dibutylester.

Epidermodysplasia verruciformis (EV) is a rare disorder characterized by disseminated cutaneous warts in predisposed patients who are highly susceptible to genus ß-papillomavirus infections. We present the case of a 40-year-old lymphocytopenic woman with a balanced chromosomal translocation and a 25-year history of refractory EV that was successfully treated with squaric acid dibutylester (SADBE) contact immunotherapy.

Acquired epidermodysplasia verruciformis in a renal transplant recipient--case report.

A 24-year-old male patient, who underwent kidney transplant six years ago due to Lupus nephritis, for the last two years presented asymptomatic erythematous scaly plaques on the abdomen and areas exposed to light. Post-transplantation immunosuppressive medications included prednisone, mycophenolate sodium and sirolimus. The histopathologic features were typical for epidermodysplasia verruciformis. Epidermodysplasia verruciformis is a rare autosomal recessive genodermatosis with increased susceptibility to specific strains of cutaneous human papilloma virus. The term ''acquired epidermodysplasia verruciformis'' was recently introduced to the literature and describes epidermodysplasia verruciformis occurring in patients with impaired cell-mediated immunity. We report an additional case associated to immunosuppression after kidney transplantation.

Epidermodysplasia verruciformis.

Epidermodysplasia verruciformis (EV) is a rare genodermatosis that predisposes certain individuals to developing cutaneous malignancies caused by infectious agents. Mutations in the transmembrane channel gene TMC6 or TMC8 create patient susceptibility to infections by human papillomavirus (HPV) and the development of EV-typical plane warts. Mainly in the UV-exposed regions, affected individuals have a lifelong increased risk for the development of cutaneous malignancy, especially squamous cell carcinoma (SCC). EV is the first disease to correlate cancer and viral infection, therefore EV now serves as the cornerstone to our understanding of viral oncogenesis. The EV model of cutaneous SCC may be applied to the general population; it is suggested that the TMC mutations impair the immunity of the patients, supporting the amplification of specific HPV types. Despite several advances in our comprehension of EV, the pathogenesis of the disease is not well understood.

Acquired epidermodysplasia verruciformis in a renal transplant recipient - Case report

A 24-year-old male patient, who underwent kidney transplant six years ago due to Lupus nephritis, for the last two years presented asymptomatic erythematous scaly plaques on the abdomen and areas exposed to light. Post-transplantation immunosuppressive medications included prednisone, mycophenolate sodium and sirolimus. The histopathologic features were typical for epidermodysplasia verruciformis. Epidermodysplasia verruciformis is a rare autosomal recessive genodermatosis with increased susceptibility to specific strains of cutaneous human papilloma virus. The term ''acquired epidermodysplasia verruciformis'' was recently introduced to the literature and describes epidermodysplasia verruciformis occurring in patients with impaired cell-mediated immunity. We report an additional case associated to immunosuppression after kidney transplantation.

Acquired epidermodysplasia verruciformis in a child with atopic dermatitis.

A 4-year-old girl with an established diagnosis of atopic dermatitis, previously severe and treated with cyclosporine, developed widespread papules that demonstrated changes consistent with epidermodysplasia verruciformis on biopsy. Human papilloma virus (HPV) typing was performed and was consistent with epidermodysplasia verruciformis-type HPV (type 5). These lesions rapidly resolved with a 2-week course of imiquimod. Rapid resolution and no family history of epidermodysplasia verruciformis make this most consistent with acquired epidermodysplasia verruciformis. This case is the first reported case of acquired epidermodysplasia verruciformis in a child without the human immunodeficiency virus and may be linked to cyclosporine use, which also has never been previously reported.