Successful treatment of generalized granuloma annulare with adalimumab

Granuloma annulare skin profile shows activation of T-helper cell type 1, T-helper cell type 2, and Janus kinase pathways

BACKGROUND

Granuloma annulare (GA) is an inflammatory skin disorder. Localized GA is often self-resolving, but generalized GA is often recalcitrant to treatments. There are no targeted treatments for GA, largely due to lack of mechanistic understanding. Recently, tumor necrosis factor antagonism showed promise in GA, suggesting an underlying immune pathogenesis.

OBJECTIVE

To elucidate the immune pathogenesis and identify potential therapeutic targets for GA.

METHODS

Lesional and nonlesional skin biopsy samples were obtained from patients with GA and evaluated for a large array of inflammatory markers compared with inflammatory markers from normal skin of healthy individuals.

RESULTS

We found differential expression of many inflammatory genes compared with normal skin. These genes were associated with T-helper (Th) cell type 1/innate immunity (tumor necrosis factor-α, interleukin [IL]-1β, IL-12/23p40, signal transducer and activator of transcription 1, chemokine [C-X-C motif] ligand 9/10), Janus kinase signaling, and Th2 (IL-4, IL-31, chemokine (C-C motif) ligands 17 and 18; P < .05). Unexpectedly, IL-4 showed significant upregulation in GA lesional skin vs control skin (15,600-fold change).

LIMITATIONS

Limited sample size.

CONCLUSIONS

Our findings shed light on the inflammatory pathways of GA, supporting the notion that immune mechanisms could be driving disease, as suggested by the promising data of tumor necrosis factor-α inhibitors in GA. The significant Janus kinase and particularly Th2 signaling in GA advocates for the investigation of specific Janus kinase- and Th2- targeted drug therapy.

ARE ANTIBIOTICS OF ANY USE IN THE MANAGEMENT OF GRANULOMA ANNULARE IN CHILDREN?

Background:

Granuloma annulare (GA) is a benign inflammatory dermatosis of unknown cause, of which generalised granuloma annulare (GGA) is a subtype that tends to be resistant to treatment. Various antibiotics have been used to treat GGA, the most recent being combination therapy with rifampicin, ofloxacin and minocycline (ROM). This study aims to explore the efficacy of antibiotics in treating GGA, and whether antibiotics may be useful in children with GGA.

Materials and Methods:

A systematic review of literature published from 1947 to 2017 was undertaken in order to evaluate the use of antibiotics in treating GGA. Data on characteristics of children with GGA were extracted and eligible studies were then qualitatively analysed.

Results:

Seven hundred and ninety (790) potential studies were identified, of which 16 were eligible for inclusion in the final analysis. Of these 16 studies, majority were case studies (n=9, 56.3%), with 2 case series (12.5%), 2 retrospective studies (12.5%) and 3 open-label prospective studies (18.8%). Main antibiotic treatments reported were either monthly combination therapy of rifampicin, ofloxacin and minocycline (ROM), or monotherapy with dapsone or doxycycline. Out of a total of 158 patients with GA, 72 patients (45.6%) were treated with antibiotics. Of the 72, 48.6% (n=35) of these patients had GGA while 4 were children; two with GA (2 with GGA), all of whom were treated with dapsone.

Conclusion:

There is paucity of evidence to support the use of antibiotics in the treatment of GGA in children. Although ROM has shown promising results in adults, more studies are needed to validate these findings in children.

[Granuloma annulare]

Granuloma annulare is a benign, chronic inflammatory skin disease. Its pathogenesis is still unclear, but reports on infections as a trigger can be found. In addition, some authors reported an association with other systemic disease, e.g., cancer, trauma, and diabetes mellitus; however, these have not been verified. The clinical picture of granuloma annulare ranges from the localized form predominantly at the extremities to disseminated, subcutaneous, or perforating forms. Diagnosis is based on the typical clinical presentation which may be confirmed by a biopsy. Histologically, necrobiotic areas within granulomatous inflammation are typical. The prognosis of the disease is good with spontaneous resolution being frequently observed, especially in localized forms. Disseminated manifestations tend to persist longer, and recurrences are reported. When choosing between different therapeutic options, the benign disease character versus the individual degree of suffering and the potential therapy side effects must be considered. For local treatment, topical application of corticosteroids is most common. Disseminated forms can be treated systemically with corticosteroids for several weeks; alternatively, dapsone, hydroxychloroquine, retinoids, fumaric acid, cyclosporine, and anti-TNFα appear to be effective.