Granulomes annulaires disséminés et immunodépression iatrogène

Granuloma annulare - is it a paraneoplastic condition for malignant lymphoma?

In recent years, an association between granuloma annulare and the occurrence of malignant cutaneous lymphomas in the sense of a facultative paraneoplasia has been observed several times. The aim of the present work is to provide an overview of the currently available literature on granuloma annulare as well as an analysis of its association with cutaneous lymphomas. Using the example of two patients with granuloma annulare and associated cutaneous lymphomas, we would like to sensitize clinically active dermatologists and dermatopathologists to the possible association between these two diseases. Characteristic features and clinicopathological signs are discussed, which should raise suspicion of an associated malignant lymphoma. It is recommended to rule out an underlying cutaneous and/or extracutaneous lymphoma in unusual clinical constellations (for instance distribution pattern, subjective complaints, age at first manifestation, lack of response to conventional therapy), especially in the absence of other known clinical triggers of granuloma annulare such as insect bites, trauma or varicella-zoster infections, among others. However, in individual cases the criteria mentioned here justify lymphoma screening.

[Generalized granuloma annulare: A clinicopathological study]

BACKGROUND

Granuloma annulare (GA) is a benign granulomatous skin disorder that is generalized (GGA) in 15 % of cases. Although many case reports describe a relationship between GGA and systemic diseases, few large series have been published, and their association is debated. We present herein a series of GGA in order to describe their clinical and histological features.

PATIENTS AND METHODS

We included all biopsy-proven cases of GA presenting at the dermatopathology laboratory of Strasbourg where generalized (i.e. over 10 lesions). Clinical features were obtained from patients' medical files.

RESULTS

We included 35 GGA, with a sex ratio of 0.5. The mean age was 54 years. Lesions were annular or non-annular in equal measure and were symptomatic in 25 % of cases. Most patients (77 %) had an associated disease, already known in 60 % of cases, including dyslipidemia (27 %), diabetes mellitus (20 %), immunosuppressive drugs (17 %), atopy (17 %), auto-immune disease (17 %), hematological disease (14 %), and cancer (9 %). Histological analysis revealed the predominant pattern to be interstitial (54 %) rather than palisading (20 %), having no correlation with clinical type. Eosinophils were frequent (46 %) in GA but were not correlated with systemic disease or drug taking. Among the 40 % of patients treated, 50 % had a successful outcome on topical corticosteroids, doxycycline, antimalarial drugs or phototherapy.

DISCUSSION

GGA differs from localized GA, which is mostly associated with an already known systemic disease, whether metabolic, infectious or neoplastic, uncorrelated with clinical or histological features, and screening is necessary.

Granulomatous dysimmune reactions (sarcoidosis, granuloma annulare, and others) on differently injured skin areas

Granulomatous disorders are chronic cell-mediated immune responses histologically characterized by collections of macrophages, epithelioid cells, and multinucleated giant cells. This disease spectrum often has an infectious origin, but sometimes neither an infective agent nor an inciting antigenic stimulus can be identified. The skin may be a preferential target for these disorders, especially in the areas that have been damaged by various forms of skin injury (eg, herpetic infections, trauma, thermal or solar burns, vaccinations, tattoos). These damaged skin sites frame the new concept of an immunocompromised cutaneous district (ICD), which defines a skin area with acquired immune dysregulation that can pave the way for the local onset of opportunistic disorders, such as infections, tumors, and granulomatous disorders. Sarcoidosis, granuloma annulare (GA), and forms of granulomatous vasculitis, such as Churg-Strauss syndrome (CSS) and Wegener's granulomatosis (WG), are the most common granulomatous disorders that occur in an ICD and may share common pathogenic mechanisms. Recent studies have found clinical and pathologic overlapping features across noninfectious granulomas. Although no unifying etiology exists, the development of granulomatous processes in the ICD has often been reported and the literature contains various hypotheses to explain it: (1) overactive immune response in a previously injured region with or without loss of immune tolerance; (2) overall reduced immune response; (3) retention of an exogeneous antigen or foreign body; (4) altered neural signaling; and (5) a combination of all the aforementioned processes. T helper cells, T regulatory cells, and macrophages, as well as a number of antigenic proteins, have been identified as potential contributing factors. In addition, a genetic predisposition and an intact systemic immune system are both instrumental for the persistence of local granuloma formation in the ICD.

Perforating neutrophilic and granulomatous dermatitis of the newborn--a clue to immunodeficiency

We report two newborns with a widespread cutaneous eruption consisting of discrete papules which evolved into vesicles, pustules, crusts, and ulcers. These healed over a 2-week period with scarring. Histopathology showed three main features--histiocytic granulomas, neutrophilic infiltration, and transepidermal elimination of degenerated collagen and debris through hair follicles. Both patients had congenital immunodeficiency. This skin condition of the newborn, with distinct clinical and histopathologic features, is a manifestation of immunodeficiency that has not been previously described.