Nodal marginal zone lymphoma in association with hydroa vacciniforme-like papulovesicular eruption, hypersensitivity to mosquito bites and insect bite-like reaction

Eosinophilic Dermatosis of Hematologic Malignancy: Emerging Evidence for the Role of Insect Bites-A Retrospective Clinico-Pathological Study of 35 Cases

Background/Objectives: Eosinophilic dermatosis of hematologic malignancy (EDHM) is a rare cutaneous disorder associated with various hematologic malignancies, most commonly chronic lymphocytic leukemia. Detailed clinicopathologic studies of EDHM are lacking and the pathogenesis remains enigmatic. Initially thought to be a hypersensitivity reaction to insect stings, subsequent reports have challenged this understanding. The prognostic implications of EDHM remain unclear. Methods: A retrospective clinicopathologic study was performed on patients diagnosed with EDHM. Hematologic and dermatologic data were reviewed. Histologic specimens were re-evaluated and lesions were classified into acute/subacute, fully developed, and chronic/regressing. Results: The study included 35 patients. In 80% of these patients, EDHM was diagnosed after the hematologic disorder. Approximately 45% of the cohort experienced hematologic disease progression or relapse, while 65% required therapeutic intervention during the course of their hematologic disease. In total, 15/19 CLL patients had non-mutated IgHV, a marker of a more aggressive hematologic disease course. Dermatologic lesion morphology was heterogeneous, with most lesions occurring on exposed areas, and a significant 94% of patients demonstrated lesion seasonality. Histopathologic findings were consistent with features typically associated with insect bites. In addition, examination of lesions at different chronological stages revealed substantial similarities with Wells syndrome. Conclusions: Our findings support the potential role of insect bites in triggering EDHM in the context of adaptive immune dysfunction. EDHM may be associated with a more aggressive disease course or may be a marker of disease progression. The observed co-occurrence of features typical of Wells syndrome in EDHM patients suggests that these conditions are part of a spectrum of disorders that vary in clinical expression.

Eosinophilic dermatosis of hematologic malignancy in patients with chronic lymphocytic leukemia/non-Hodgkin's B lymphoma: a single center prospective clinico-pathological study

Background

The pathogenesis of eosinophilic dermatosis of hematologic malignancy (EDHM) is poorly understood. Previously thought to be a hypersensitivity reaction to insect bites, immune dysregulation and cytokine imbalance are now thought to be responsible. Its prognostic significance is unclear.

Objective

To describe the clinical, pathological and immunological findings in a series of oncohematological patients with EDHM.

Methods

An observational prospective cohort study of oncohematological patients receiving a diagnosis of EDHM between April 2017 and December 2018.

Results

A total of 15 patients with EDHM (10 females and 5 males) were identified among 422 oncohematological patients. Disease presentation varied from firm erythematous papules to more polymorphic presentations. The lesions were most prevalent on the exposed sites, 8/15 patients recalled an insect bite. Lesion seasonality was reported in 13/15 patients. IgE levels were elevated in six patients, circulating IL-4 and IL-5 were within a normal range. Twelve out of 15 patients developed skin manifestations after chemotherapy. The infiltrate could be eosinophil-rich or lymphocytic-rich. Interestingly, the histopathologic findings were in accordance with arthropod bites.

Conclusion

A role for insect bites in EDHM is supported by our findings. EDHM may be related to aggressive hematologic disease.

Epstein - Barr virus positive T and NK-cell lymphoproliferations: Morphological features and differential diagnosis

The spectrum of Epstein-Barr virus (EBV)-positive T and NK-cell lymphoproliferations is broad and ranges from reactive self-limited disorders to neoplastic processes with a fulminant clinical course. EBV plays an important role promoting lymphomagenesis, although the precise mechanisms remain elusive. EBV-positive lymphoproliferative disorders (LPD) are more common in East Asia (China, Japan, Korea and Taiwan), and Latin America suggesting a strong genetic predisposition. The revised 2016 World Health Organization (WHO) lymphoma classification recognizes the following malignant NK- and T-cell lymphomas; extranodal NK/T-cell lymphoma, nasal type (ENKTCL), aggressive NK-cell leukemia (ANKL), and the provisional entity within the group of peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) "primary EBV-positive nodal T or NK cell lymphoma". Disorders presenting mainly in children and young adults include chronic active EBV infection (CAEBV) - systemic and cutaneous forms - which are not considered malignant disorders but were included in the WHO classification for the first time because of the differential diagnosis with other T- or NK-cell lymphomas. CAEBV, cutaneous form, includes hydroa vacciniforme-like LPD (HV-LPD) and severe mosquito bite allergy (SMBA). Finally, systemic EBV-positive T-cell lymphoma of childhood was recognized as lymphoma because of its fulminant clinical course. Given the shared pathogenesis of these disorders, overlapping features are common demanding a close clinical, morphological and molecular correlation for an accurate diagnosis. This review summarizes the clinical, histopathological and molecular features of EBV-associated T and NK-cell LPD, highlighting the main features that might aid in the differential diagnosis.

Hydroa Vacciniforme-Like Lymphoma with Systemic Symptoms: Two Case Reports

Two Chinese children presented with relapsing papules, vesicles, ulcers on the face and limbs with systemic symptoms being caused by mosquito bite. Lesion biopsy revealed atypical lymphocyte in the dermis and subcutis. Immunohistochemistry identified cells as positive for CD3, CD45RO, TIA-1 and EBER. Taken together, both the patients were diagnosed with hydroa vacciniforme-like lymphoma. Two patients showed significant improvement in clinical symptoms after being treated with acyclovir, low dose predisone and IFN-α.

Eosinophilic dermatosis of hematologic malignancy mimicking varicella zoster infection: report in a woman with chronic lymphocytic leukemia and review of the literature

Eosinophilic dermatosis of hematologic malignancy is a rare papulovesicular eruption that presents in patients with hematoproliferative disorders, particularly chronic lymphocytic leukemia. A 59-year-old woman with chronic lymphocytic leukemia who developed eosinophilic dermatosis of hematologic malignancy mimicking varicella zoster infection is described. PubMed database was searched with the key words: chronic, dermatosis, eosinophilic, hematologic, infection, leukemia, lymphocytic, malignancy, varicella, zoster. The papers generated by the search and their references were reviewed. The patient presented, on more than 20 occasions, with a dermatomal vesicular eruption. Her oncologist, based on the clinical presentation, treated each episode as recurrent varicella zoster virus infection. A complete workup of the patient not only demonstrated negative viral studies but also revealed pathologic changes consistent with eosinophilic dermatosis of hematologic malignancy on lesional skin biopsy. The recurrence of the patient's dermatosis was less frequent when her malignancy was under better control. Eosinophilic dermatosis of hematologic malignancy may mimic other reactive dermatoses. The morphology of our patient's recurrent dermatosis resembled varicella zoster virus infection. Disseminated zoster virus infection with dermatomal and non-dermatomal distribution should be added to the clinical differential diagnosis of eosinophilic dermatosis of hematologic malignancy.

Primary Indeterminate Dendritic Cell Tumor of Skin Correlated to Mosquito Bite

Primary indeterminate dendritic cell tumor (IDCT) is an extremely neoplastic dendritic cell disorder. Little is known about its pathogenesis, etiology, and prognostic factors because of its rarity. Herein, we present a case report of a skin IDCT that arose in mosquito bite and discuss the correlation between hypersensitivity to mosquito bites and leukemia/lymphoma.A 28-year old man presented with multiple widespread cutaneous plaques and nodules 8 months after being bitten by a mosquito on his back. Dermatological examination revealed multiple skin-colored, well-demarcated plaques and nodules measuring approximately 0.5 to 1.8 cm in diameter all over the body. A biopsy of the skin lesion was taken. Morphologically, the dermis was effaced by round or polygonal cells with oval nuclei and abundant eosinophilic cytoplasm, arranged in nests and in some areas in a sheet-like pattern. The tumor cells were positive for CD68, CD1a, and S-100, whereas negative for Langerin and lack Birbeck granules ultrastructurally. A diagnosis of IDCT was made. No treatment was given. The patient was alive with spontaneous disease regression after 17 months of follow-up.IDCT is an extremely rare disease and may be associated with mosquito bite.

Epstein-Barr virus-associated T/natural killer-cell lymphoproliferative disorders

Primary infection with Epstein-Barr virus (EBV) is usually asymptomatic and, in a normal host, EBV remains latent in B cells after primary infection for the remainder of life. Uncommonly, EBV can infect T or natural killer (NK) cells in a person with a defect in innate immunity, and EBV infection can cause unique systemic lymphoproliferative diseases (LPD) of childhood. Primary infection in young children can be complicated by hemophagocytic lymphohistiocytosis or fulminant systemic T-cell LPD of childhood. Uncommonly, patients can develop chronic active EBV (CAEBV) disease-type T/NK LPD, which includes CAEBV infection of the systemic form, hydroa vacciniforme-like T-cell LPD, and mosquito-bite hypersensitivity. The clinical course of CAEBV disease-type T/NK LPD can be smoldering, persistent or progressive, depending on the balance between viral factors and host immunity. Aggressive NK-cell leukemia, hydroa vacciniforme-like T-cell lymphoma, or uncommonly extranodal NK/T-cell lymphoma can develop in children and young adults with CAEBV disease-type T/NK-cell LPD. Extranodal T/NK-cell lymphoma is a disease of adults, and its incidence begins to increase in the third decade and comprises the major subtype of T/NK LPD throughout life. Aggressive NK-cell leukemia and nodal T/NK-cell lymphoma of the elderly are fulminant diseases, and immune senescence may be an important pathogenetic factor. This review describes the current progress in identifying different types of EBV-associated T/NK-cell LPD and includes a brief presentation of data from Korea.

Lymphoproliferative Disease of the Orbit

Lymphoproliferative diseases of the orbit account for majority of orbital tumors. The pathologies range from reactive lymphoid hyperplasia to specific IgG4-related inflammation to malignant lymphomas. This review summarizes current concepts regarding pathology, clinical presentation, diagnosis, staging, and treatment strategies of major orbital lymphoproliferative diseases based on updated and relevant bibliography.

Anaplastic lymphoma kinase-positive anaplastic large cell lymphoma arising in a patient with hypersensitivity to mosquito bites

Hypersensitivity to mosquito bites is defined as the appearance of intense skin reactive lesions and systemic symptoms subsequent to mosquito bites. Most cases of hypersensitivity to mosquito bites reported thus far have been associated with chronic Epstein-Barr virus infection or natural killer cell leukemia/lymphoma. In this study, we describe the case of an 18-year-old Korean boy who had hypersensitivity to mosquito bites associated with primary systemic anaplastic lymphoma kinase-positive anaplastic large cell lymphoma. After a mosquito bite, the patient developed a progressive cutaneous nodule on his left lower leg and regional lymphadenopathy in the left inguinal area. The histopathological and immunohistochemical findings suggested anaplastic lymphoma kinase-positive anaplastic large cell lymphoma. Positron emission tomography-computed tomography revealed increased fluorodeoxyglucose uptake in the left T4 vertebrae, left external iliac lymph nodes, left inguinal lymph nodes, and lateral subcutaneous region of the left lower leg. According to the clinical, histopathological, and immunohistochemical findings, as well as the imaging data, the patient was diagnosed with primary systemic anaplastic lymphoma kinase-positive anaplastic large cell lymphoma. Consequently, the patient received a total of 6 cycles of cyclophosphamide + doxorubicin + vincristine + prednisolone chemotherapy at 3-week intervals, after which the lesions regressed.

Recognizing nodal marginal zone lymphoma: recent advances and pitfalls. A systematic review

The diagnosis of nodal marginal zone lymphoma is one of the remaining problem areas in hematopathology. Because no established positive markers exist for this lymphoma, it is frequently a diagnosis of exclusion, making distinction from other low-grade B-cell lymphomas difficult or even impossible. This systematic review summarizes and discusses the current knowledge on nodal marginal zone lymphoma, including clinical features, epidemiology and etiology, histology, and cytogenetic and molecular features. In particular, recent advances in diagnostics and pathogenesis are discussed. New immunohistochemical markers have become available that could be used as positive markers for nodal marginal zone lymphoma. These markers could be used to ensure more homogeneous study groups in future research. Also, recent gene expression studies and studies describing specific gene mutations have provided clues to the pathogenesis of nodal marginal zone lymphoma, suggesting deregulation of the nuclear factor kappa B pathway. Nevertheless, nodal marginal zone lymphoma remains an enigmatic entity, requiring further study to define its pathogenesis to allow an accurate diagnosis and tailored treatment. However, recent data indicate that it is not related to splenic or extranodal lymphoma, and that it is also not related to lymphoplasmacytic lymphoma. Thus, even though the diagnosis is not always easy, it is clearly a separate entity.

Insect-bite-like reaction in patients with chronic lymphocytic leukemia: a study from the Israeli Chronic Lymphocytic Leukemia Study Group

An insect-bite-like reaction is known to occur in patients with chronic lymphocytic leukemia (CLL). Most of the literature, however, consists of isolated case reports or small case series. The aim of this retrospective study was to review the national experience with insect-bite-like reaction in a large group of patients with CLL. The study cohort of patients with these skin reactions consisted of 48 patients (25 males, 23 females) of mean age 64.8 yr (range 33-89) at skin eruption. Data on clinical, histologic, immunophenotypic, and cytogenetic characteristics, treatment, and outcome were collected from the medical files. Mean time between diagnosis of CLL and appearance of the skin lesions was 3.1 yr (range -4 to 14 yr). The eruption was not related to disease activity or the course of the hematological disease. The eruption preceded the diagnosis of CLL in 10 patients (by 0-4 yr); and followed the diagnosis in 36; in 11 patients, it occurred during therapy for CLL and in nine after therapy. Mean duration of the skin findings was 21.5 months (range 0.3-132). The eruption usually presented in summer, although it occurred also at other times of the year, and predominantly affected the upper and lower limbs, although it also appeared on unexposed areas. Treatment included local ointments, antihistaminics, oral steroids, antibiotics, phototherapy, and dapsone with varying responses. Insect-bite-like reactions is a relatively common and disturbing skin reaction in CLL patients, it may be related to the immune dysregulation accompanying CLL and further exacerbated by external factors, including actual insect bites, chemoimmunotherapy, and pyogenic infection.

Advances in mosquito allergy

PURPOSE OF REVIEW

Allergic reactions, including severe local and systemic reactions to mosquito bites, are immunological in nature, and involve immunoglobulin E, immunoglobulin G, and T-lymphocyte-mediated hypersensitivities in response to allergens in mosquito saliva. Naturally acquired desensitization to mosquito saliva may occur during childhood or during long-term exposure to mosquitoes. Due to the lack of availability of mosquito salivary preparations for use in skin tests and in-vitro tests, allergic reactions to mosquito bites are under diagnosed and under treated.

RECENT FINDINGS

Recombinant saliva allergens with biological activity are being developed. Recombinant Aedes aegypti salivary allergen rAed a 2 has been expressed, purified, characterized and used in in-vitro diagnosis of mosquito allergy. Mosquito saliva-induced non-immunoglobulin E-mediated skin mast cell degranulation was found to induce macrophage-inflammatory protein 2 in the skin and interleukin-10 in draining lymph nodes.

SUMMARY

In this review, we discuss the allergic reactions to mosquito salivary allergens, the immune mechanisms involved, natural desensitization and immunotherapy with mosquito extracts, characteristics of salivary allergens and their recombinant forms, and prevention and treatment of allergic reactions to mosquito bites. Eventually, recombinant salivary allergens will significantly improve the diagnosis of mosquito allergy, and will also improve specific immunotherapy for patients with systemic reactions to mosquito bites.