Mycosis on mycosis fungoides: zoophilic dermatophytosis selectively superimposed on pre-existing cutaneous T-cell lymphoma (mycosis fungoides) plaques

Is it mycosis fungoides? A comprehensive guide to reaching the diagnosis and avoiding common pitfalls

Mycosis Fungoides (MF) is known as 'the great mimicker' due to its capacity to emulate several dermatoses, both in the clinic and on histology. This often leads to the diagnosis being missed or delayed, which consequently leads to poorer prognosis. For a timely diagnosis, it is crucial that the physician is aware of the various clinical and histological presentations of MF, as well as the proper diagnostic protocols. In the current review, we concisely encapsulate all the variants of MF as well has the conditions it mimics clinically and histologically. Through this, we aim to provide clinicians with a holistic picture of MF and help them determine when to suspect this disease and steps to take in order to nail the diagnosis.

Mycosis Fungoides with Tinea Pseudoimbricata Owing to Trichophyton Rubrum Infection

Background:

Dermatophytes can mimic or possibly trigger mycosis fungoides (MF).

Objectives:

To present the case of a 55-year-old male referred for MF refractory to therapy who instead had extensive tinea pseudoimbricata (concentric, annular lesions secondary to Trichophyton rubrum).

Methods:

Case report with biopsy and cultures.

Results:

Oral antifungal therapy dramatically improved his lesions, and only a few MF lesions persisted after treatment.

Conclusions:

Concurrent tinea may confound the treatment and diagnosis of MF.

Cancers mimicking fungal infections

Primary and metastatic malignancies may occasionally mimic or coexist with cutaneous fungal infections. The authors report 3 cases of cancers that were initially presumed to be cutaneous fungal infections. Dermatologists should maintain a low threshold for skin biopsy in patients with persistent or refractory fungal infections.

Trichophyton Schoenleinii-induced widespread tinea corporis mimicking parapsoriasis

We report a case of extensive tinea corporis in an 80-year-old woman on her forearms, thighs, legs, buttocks and trunk, mimicking parapsoriasis due to Trichophyton schoenleinii, without scalp involvement. Diagnosis of Trichophyton schoenleinii was confirmed by microscopy and mycological culture specimens.

Histologic mimickers of mycosis fungoides: a review

Mycosis fungoides (MF) is a rare type of non-Hodgkin's lymphoma affecting the skin. Because MF develops slowly over several years and may have a variety of clinical presentations, including itchy patches, plaques or tumors that may be confused with common benign conditions such as eczema and psoriasis, the disease presents a diagnostic challenge. The average time to diagnosis varies but is frequently as long as 3 to 6 years. Skin biopsies frequently reveal non-specific features of several dermatoses; thus, histologic evaluation of the disease is also challenging. Importantly, various significant and/or benign conditions may mimic MF histologically and result in a misdiagnosis of MF. Here we review the reported histologic mimickers of MF and discuss both similar and differentiating features of each, in order to aid in more accurate interpretation of diagnostically challenging skin biopsies. Clinicopathologic correlation is ultimately essential to make accurate diagnosis of MF and its histologic mimickers.

Mycosis fungoides: a dermatological masquerader

Mycosis fungoides (MF), a low-grade lymphoproliferative disorder, is the most common type of cutaneous T-cell lymphoma. Typically, neoplastic T cells localize to the skin and produce patches, plaques, tumours or erythroderma. Diagnosis of MF can be difficult due to highly variable presentations and the sometimes nonspecific nature of histological findings. Molecular biology has improved the diagnostic accuracy. Nevertheless, clinical experience is of substantial importance as MF can resemble a wide variety of skin diseases. We performed a literature review and found that MF can mimic >50 different clinical entities. We present a structured framework of clinical variations of classical, unusual and distinct forms of MF. Distinct subforms such as ichthyotic MF, adnexotropic (including syringotropic and folliculotropic) MF, MF with follicular mucinosis, granulomatous MF with granulomatous slack skin and papuloerythroderma of Ofuji are delineated in more detail.

[Extensive cutaneous candidiasis revealing cutaneous T-cell lymphoma: 2 cases]

BACKGROUND

During the course of immunodeficiency diseases, severe candidiasis can occur with extensive cutaneous and mucous membrane lesions. However, blood dyscrasias are very rarely revealed by diffuse candidiasis. We report two case of cutaneous T-cell lymphoma revealed by extensive and atypical cutaneous candidiasis.

PATIENTS AND METHODS

Case No. 1:A 72-year-old woman presented a pruritic rash of circinate, serpiginous patches on glabrous skin and skinfolds with multiple intertrigo and rapidly worsening palmoplantar keratoderma. All mycological skin specimens tested positive for Candida albicans. Histological examination of a biopsy sample from a serpiginous patch revealed the presence of fungal elements while palmoplantar keratoderma biopsy showed an epidermotropic lymphocytic infiltrate in the superficial dermis evocative of mycosis fungoides. Blood tests showed a white cell count of 28 600/mm3 with 14% circulating Sezary cells and a T-cell clone. The T-cell lymphoma was treated with methotrexate, but the disease worsened a few months later, progressing to CD30- large T-cell pleomorphic lymphoma. The patient died of severe sepsis. Case No 2:A 60-year-old man presented a macular rash over the face, trunk and skinfolds as well as erythematous scaly annular plaques of the glabrous skin with lymphadenopathy. Cultures of skin scrapings were all positive for Candida albicans. Blood tests showed a white cell count of 15 000/mm3 with 30% circulating Sezary cells. A trunk patch biopsy revealed the histological appearance of mycosis fungoides. There was a T-cell clone in the peripheral blood and skin.

DISCUSSION

In both cases, the patients presented with widespread annular and erythematous scaly lesions of the glabrous skin and skinfolds with evidence of Candida albicans on fungal tests of all skin scrapings. The discovery of circulating Sezary cells on a systematic smear for hyperleukocytosis led us to suspect underlying cutaneous T-cell lymphoma, which was confirmed by biopsy of the skin lesions accompanying the mycoses. Widespread cutaneous candidiasis can occur in patients with cell-mediated immunodepression. Cutaneous T-cell lymphoma can enhance such candidiasis through interference with skin integrity and impairment of cell-mediated immunity, with large amounts of IL10 and TGF-B, increased secretion of soluble interleukin-2 receptors (CD25) and impaired CD8 suppressor cell function.