An observational study of the efficacy of azithromycin in erythema annulare centrifugum

Evaluation of Clinicopathological Features and Associated Conditions in Erythema Annulare Centrifugum: A Retrospective Observational Analysis of 63 Patients

INTRODUCTION

Erythema annulare centrifugum (EAC) is a rare reactive disease that typically presents as annular or polycyclic erythematous lesions. There are few studies about EAC in the literature; therefore, data on the pathogenesis of the disease are limited.

OBJECTIVES

We aimed to examine the demographic, clinical, pathological characteristics and associated conditions of the patients with EAC.

METHODS

We analyzed records of the patients with EAC who admitted to our clinic in the last four years retrospectively.

RESULTS

A total of 63 patients, 39 women and 24 men, were included in our study. The mean age of the patients was 47.8±11.2 years. The mean disease duration was 15.54±12 months. The trunk and thigh were the most commonly involved sites (49%, 33%). Associated conditions were identified in 52.3% of the patients. Infections (N = 16), malignancies (N = 6), rheumatic diseases (n=4) and drugs (n=4) were the most common precipitating factors respectively. The most common infections were superficial fungal infections and Helicobacter pylori infection. Histopathologically, 10 patients had deep type and 53 patients had superficial type EAC. We determined that the disease duration from the onset of the disease was longer (12.3 versus 16.2 months) and the number of attacks (1.2 versus 2.8 attacks) was higher in the superficial type when compared to the deep type (P = 0.042, P = 0.038).

CONCLUSIONS

In our study, infections, malignancies and rheumatic diseases were among the most common etiologic factors. We would also like to draw attention to Helicobacter pylori infection as a precipitating factor which may be a novel finding.

Figurate erythemas - update and diagnostic approach

Figurate erythemas (FE) represent an etiopathophysiologically heterogeneous group of diseases defined by their characteristic annular erythematous skin lesions. Diagnosis is made primarily by clinical examination together with histological findings; often it is a diagnosis made by exclusion. While some authors discuss FE as clinical reaction pattern rather than distinct clinical entities, others identify four classic FE: erythema annulare centrifugum, erythema gyratum repens, erythema migrans and erythema marginatum. The differential diagnoses of FE are numerous and often challenging. We therefore present a potential diagnostic algorithm for FE that discriminates the differentials according to their temporal evolution and the clinical/histological phenotype of the various subtypes. Since some FE may present with an underlying malignancy, diligent clinicians are needed when dealing with those entities.

Recurrent Erythema Annulare Centrifugum due to Influenza Type A

Erythema annulare centrifugum (EAC) is a rare erythema characterized by erythematous and urticarial papules or annular plaques that enlarges centrifugally. The lesions usually involve the thighs and the legs. Several disorders are occasionally associated with EAC, infections, including mycoses, bacteria, or viruses and drugs have also been regarded as possible causes of this eruption. We present a 42-year-old dark-skinned woman affected by recurrent EAC that appeared secondary to influenza type A (H1N1). Histopathology showed a superficial form of EAC. In our case, a previous cytomegalovirus and Epstein-Barr virus (EBV) infection were identified and no underlying other diseases were found. Clarithromycin with calcipotriol betamethasone treatment was temporarily efficacious. In the last 3 years, the lesions started to appear every 2 weeks and tended to regress with local treatment after a variable period. We believe that the latent cytomegalovirus and the reactivity induced by EBV combined with influenza can determine, in our case, a cell mediate cutaneous immune response, which leads to the peculiar inflammatory disease known as EAC.