Rajalakshmi Tirumalae

Histopathological and immunohistochemical features of nodular podoconiosis

Podoconiosis is a familial geochemical dermatosis which is common in Ethiopia but relatively unknown in Europe/United States. It is related to exposure of bare feet to volcanic soil and presents with extensive bilateral lymphedema of legs and feet. Histopathological and immunohistochemical features of it have not been described yet.

Benign vs. Malignant skin adnexal neoplasms: How useful are silhouettes?

Background: Skin adnexal tumors are daunting diagnostic problems. Cytologic atypia does not always imply malignancy and “typia” does not underscore a benign course. Bernard Ackerman first described criteria on silhouettes that enable distinction between the two. Aims: To evaluate the histologic features on silhouettes of benign and malignant skin adnexal tumors. To identify overlaps and confounding features. Materials and Methods: A blinded retrospective review of all skin adnexal neoplasms between 1995 and 2007 was done, with a total of 68 cases. We studied 16 histologic parameters on scanner view and categorized them as benign or malignant. They were compared with the final histologic diagnosis. Statistical analysis was performed using chi-square test. Results: 15 criteria attained statistical significance. Features that proved highly sensitive and specific were: Circumscription, ulceration, uniform size of cell aggregates, discrete arrangement, preserved adnexae and necrosis. Criteria that were sensitive but not very specific include: Symmetry, V-shape, vertical orientation, smooth margins, compressed fibrous tissue, type of clefting, shelling out and geometric shapes. Presence of epithelial cells in singles was not helpful. Conclusion: Malignant skin adnexal tumors are differentiated accurately from benign ones by their contrasting silhouettes. Pathologists should heed the impression formed on scanner view, before evaluating cytologic features.

Clinicopathologic profile of hypopigmented mycosis fungoides in India.

Background Hypopigmented mycosis fungoides (HMF) is an under recognized disease in India, which is often mistaken for Hansen disease or vitiligo, resulting in delayed diagnosis and treatment. Aim To describe the clinical, histopathologic and immunohistochemical features of HMF in Indian patients. Materials and methods All cases presenting as hypopigmented lesions that were signed out as MF between 2001 and 2009 (15 cases) were included. Clinical data and histopathology slides were reviewed. Immunostains for CD4, CD8, and CD1a were done, where tissue was available. Results The age ranged from 14 to 38 years with a male preponderance. The commonest presentation was multiple hypopigmented patches on limbs and trunk with the duration of the lesions varying from 4 months to 14 years. All cases showed a psoriasiform/lichenoid epidermal pattern, disproportionate epidermotropism, basilar tagging of lymphocytes, monomorphous lymphocytes, haloed lymphocytes, and wiry dermal collagen. Other important findings were infiltration of hair follicles, larger epidermal lymphocytes, atypia of dermal lymphocytes, and stuffed dermal papillae. Dermal edema was absent in all cases. Immunohistochemistry done on 10 cases showed a CD8 phenotype in 6 cases and CD4 phenotype in the remaining 4 cases. Conclusions Histopathology supplemented by immunohistochemistry is reliable in making a diagnosis of HMF. It is important to be aware of this uncommon, yet significant disease.

Paraneoplastic multicentric reticulohistiocytosis: A clinicopathologic challenge

Multicentric Reticulohistiocytosis (MRH) is a rare, systemic non-Langerhans cell histiocytosis (non-LCH) with prominent joint and skin manifestations. It is mostly self limiting. However, 15-30% of the cases are associated with malignancy and carry a poor prognosis. We report the case of a 42-year-old man who presented with multiple reddish-brown papules that on biopsy showed aggregates of oncocytic histiocytes with several multinucleate giant cells. Immunostains were positive for CD 68, CD 45 and were negative for S-100, CD1a. An impression of multicentric reticulohistiocytosis (MRH) was made, with the recommendation to screen for malignancy. Electron microscopy of the skin lesions showed features consistent with non-Langerhans cell histiocytosis. The patient was later diagnosed with acute myeloid leukemia at a follow-up visit several months later. Thus, it appears prudent to screen and follow-up adults with MRH, to identify an underlying malignant condition.

Lymphocytic thrombophilic arteritis: An enigma

A 55-year-old woman presented with a 5-year history of livedo racemosa on her limbs. Histology showed vasculitis of medium-sized arteries with a circumferential, hyalinised, intraluminal fibrin ring. Her laboratory investigations did not indicate any underlying systemic disease. The findings were consistent with lymphocytic thrombophilic arteritis (LTA), alias macular arteritis, which is a recently described entity. The importance of LTA lies in the fact that it is a close clinical and microscopic mimic of polyarteritis nodosa (PAN). LTA is believed to be a distinct entity by some and as a form of PAN by others. We have discussed this case in our report.

Psoriasiform dermatoses: Microscopic approach

Psoriasiform dermatoses often pose challenges to both dermatologists and pathologists alike. With proper clinicopathologic correlation and a systematic approach, it is possible to arrive at a specific diagnosis in most cases. This article attempts to outline a practical, step-wise method of looking at these cases and highlights some important clues in individual conditions.

Origin Use of CD4, CD8, and CD1a Immunostains in Distinguishing Mycosis Fungoides from its Inflammatory Mimics: A Pilot Study.

Patch-stage/early mycosis fungoides (MF) is difficult to differentiate from benign dermatoses, despite several robust histologic criteria. Most studies include advanced lesions and data about early disease is limited. Objectives: (1) To compare the CD4:CD8 ratio in patch-stage MF versus inflammatory mimics. (2) To study patterns of CD1a expression in the epidermis and dermis in the two groups. Materials and Methods: Twenty cases each of early MF and inflammatory dermatoses were selected. The diagnoses were established after clinicopathologic correlation, repeat biopsies, and follow-up. The inflammatory group included pityriasis lichenoides chronica, actinic reticuloid, lichenoid purpura, and various psoriasiform dermatoses. Immunohistochemistry was done for CD4, CD8, and CD1a. Epidermal CD4, CD8 cells were quantified and CD1a was graded semi-quantitatively in the epidermis and dermis. Results: The average CD4:CD8 ratio was 4.2 in MF (range: 1-16.8), and 0.9 in inflammatory diseases (range: 0.43-5), which was statistically significant (P < 0.0001). None of the MF cases had a ratio <1. Four cases of pityriasis lichenoides chronica had a ratio >1. CD1a cells had a continuous or confluent epidermal pattern in almost all cases of MF, while they occurred as small or large groups in the dermis. In inflammatory dermatoses, there were either isolated or scattered CD1a+ cells in both epidermis and dermis. Conclusions: Elevated CD4:CD8 ratio favors MF. But there is an overlap in the lower range with pityriasis lichenoides chronica. These cases require good clinicopathologic correlation and follow-up. Patterns of CD1a expression are more reliable. Immunostains buttress morphology and are a valuable addition.

Disseminated cutaneous Ochroconis gallopava infection in an immunocompetent host: an unusual concurrence – a case report and review of cases reported

Introduction The incidence of deep fungal infections has increased significantly, especially in the background of human immunodeficiency virus (HIV) and immunosuppression. During this period, there has been a parallel emergence in infections due to newer pathogenic fungi that were earlier considered to be non‐pathogenic or saprophytic. Ochroconis gallopava (O. gallopava) is a neurotropic, dematiaceous fungus seldom isolated as a cause of phaeohyphomycosis in humans. Ever since its initial identification as a human pathogen, only 33 reports are available so far, affecting post transplant or immunocompromised patients. It causes severe systemic infections but rarely presents with cutaneous lesions. To the best of our knowledge, there are no reports of O. gallopava presenting primarily as cutaneous lesions in immunocompetent individuals. Herein we report one such case of primary cutaneous phaeohyphomycosis due to O. gallopava in an apparently normal male and briefly review the cases published.

Primary pleural non-Hodgkin lymphoma in a child--an exceedingly rare disease.

Primary pleural lymphomas are very rare. Two types are described in the literature: primary effusion lymphoma, in the setting of human immunodeficiency virus infection, and pyothorax-associated lymphomas, with a strong Epstein-Barr virus association. We report a rare case of a primary pleural lymphoma in a 12-year-old immunocompetent girl who presented with a hemorrhagic pleural effusion and had plaque-like thickening of the pleura. The histologic and immunophenotypic findings conformed to that of a diffuse large B-cell lymphoma (CD20 positive).

Anaplastic lymphoma kinase-positive primary cutaneous anaplastic large cell lymphoma- Is it a new variant?

Anaplastic large cell cutaneous lymphomas are clinically and pathologically heterogeneous, CD30 + (Ki-1) lymphoproliferative disorders. The importance of anaplastic lymphoma kinase (ALK) positivity is well known in the prognosis of primary systemic anaplastic large cell cutaneous lymphomas; however, the same in primary cutaneous anaplastic large cell cutaneous lymphomas is not much clear. Herein we report a 65-year-old male with an 18-month history of minimally pruritic localized nodulo-plaque lesion over lower back. Histology revealed cutaneous large cell lymphoma and immunohistochemical staining showed positivity for CD30, CD3 and ALK. The role of ALK positivity in pcALCL is discussed in this article.