Erythromycin as a Safe and Effective Treatment Option for 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 annulare erythemas

T. Colcott Fox (1849-1916) first introduced in 1889 the term "figurate erythemas." According to the clinical pattern, figurate erythemas are annular, circinate, concentric, polycyclic, or arciform. The most important figurate annulare erythemas are erythema annulare centrifugum, erythema marginatum, erythema gyratum repens, erythema migrans, erythema chronicum migrans, and the pediatric annular erythemas. Erythema annulare centrifugum might be due to fungal, bacterial, or viral infections or drugs. It tends to spread centrifugally while developing central clearing. The most common locations are the trunk and the proximal extremities. Individual lesions last from several days to weeks and may resolve spontaneously. Erythema marginatum is one of the criteria for the diagnosis of acute rheumatic fever, but it also might be seen as a symptom of other diseases such as hereditary angioedema with C1-inhibitor deficiency and psittacosis. The typical clinical picture is presented by serpiginous erythematous macules and plaques with central clearing and accentuated borders. Erythema gyratum repens is a figurate erythema associated with internal malignancy. It has been linked especially to lung, esophageal, and breast cancers. Erythema gyratum repens is characterized by multiple erythematous, rounded macules or papules, rapidly progressing and forming concentric bands with an unique wood-grained appearance with desquamation on the edges of the erythema. Erythema chronicum migrans is the most common sign of infection with Borrelia burgdorferi and other Borrelia species. It is characterized by a round or oval erythematous or livid macule with a central depressed or raised area on the spot of a previous tick bite. Erythema migrans grows centrifugally and slowly in a matter of days or weeks. Central clearing is observed in 60% of patients, thus forming a targetoid appearance of the lesion. Many other figurate erythemas can be observed in infancy (pediatric annular erythemas). To this group belong neonatal lupus, erythema gyratum atrophicans transiens neonatale, annular centrifugal erythema, familial annular erythema, annular erythema of infancy, eosinophilic annular erythema, and figurate neutrophilic erythema of infancy. The treatment of the various types of figurate erythemas should be etiologic, and when the underlying condition is addressed, the therapy usually is successful.

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

Erythema annulare centrifugum (EAC) is a form of figurate erythema consequent to a cutaneous hypersensitivity reaction to an underlying agent. In the present study, we aimed to assess the role of oral azithromycin in cases of idiopathic EAC. We performed an open trial of azithromycin in 10 patients with idiopathic EAC. Histopathological examination of biopsies was performed to exclude any alternative diagnosis and to assess the depth of the infiltrate. Patients were administered oral azithromycin 250 mg once daily until clinical resolution of the disease, and followed up regularly to monitor for possible relapse. Histopathological examination of the 10 biopsies revealed superficial pattern in 3, deep pattern in 2 and mixed pattern in the remaining 5. Of the 10 patients, 8 responded to azithromycin 250 mg, with no relapse during follow-up. Oral azithromycin might be a promising therapy in cases of idiopathic EAC. Cases with a superficial pattern respond earlier than cases with a deep pattern.

Cutaneous Markers of Systemic Disease in the Lower Extremity

The skin of the lower extremity can be a helpful diagnostic tool for systemic disease. Diabetes, renal disease, genetic disorders, and even cancer can have cutaneous manifestations in the legs and feet; moreover, proper diagnosis can facilitate earlier treatment of these diseases and not only clear up the skin symptoms but also bring about resolution of the systemic disease causing them. Although not comprehensive, this article discusses many of these disorders presenting with integumentary manifestations in the lower extremities. Where appropriate, it also enumerates the treatments involved, both systemic and localized.