Cutaneous actinomycosis associated with anti-TNF-alpha therapy: report of two cases

Disseminated cutaneous Actinomyces bovis infection in an immunocompromised host: case report and review of the literature

Background

Actinomycosis is an uncommon endogenous bacterial infection caused by Actinomyces species, characterized by the development of abscesses, tissue fibrosis, and fistulisation. It remains a diagnostic challenge, due to its similarities with diverse aetiologies’ presentation, such as neoplasms, tuberculosis, or fungal infections. Actinomyces bovis is a microorganism rarely reported as a cause of human disease. Cutaneous involvement is sporadic. In this case, Actinomyces bovis was responsible for disseminated cutaneous disease in an immunosuppressed patient.

Case presentation

We report the case of a 69-year-old female with multiple skin masses, under immunosuppressive therapy due to ulcerative colitis. Imaging exams were compatible with multiple cutaneous abscesses in the cervicofacial region and limbs. Actinomyces bovis was isolated in culture after abscess drainage. Antimicrobial therapy with parenteral penicillin G and oral amoxicillin was administered for 6 months, with complete resolution of cutaneous lesions and no relapse of the infection.

Conclusions

Considering actinomycosis as a possible diagnosis in the presence of subacute/chronic recurrent mass-like cutaneous lesions, especially in the setting of immunosuppression, may reduce the burden associated with delayed diagnosis and incorrect treatment and provide better outcomes and improvement of patient’s quality of life.

A 27-Year-Old Man With Multiple Cavitary Lung Lesions

CASE PRESENTATION

A 27-year-old Lebanese man was admitted to our department for multiple pulmonary lesions. The patient had reported persistent fever, cough, shortness of breath, and weight loss since his return from Lebanon 6 weeks earlier. He had been diagnosed with a severe form of Behçet disease 4 years ago, for which the ongoing treatment was a corticosteroid therapy associated with methotrexate and infliximab.

Actinomycosis: a frequently forgotten disease

Actinomycosis is a rare subacute or chronic, endogenous infection mainly by Actinomyces species, showing low virulence through fimbriae and biofilms. Cervicofacial, thoracic, abdominal, pelvic and sometimes cerebral, laryngeal, urinary and other regions can be affected. Actinomycosis mimics other diseases, often malignancy. Disease risk in immunocompromised subjects needs clarification. Diagnosis is often delayed and 'sulfur granules' are helpful but nonspecific. Culture requires immediate specimen transport and prolonged anaerobic incubation. Imaging, histology, cytology, matrix-assisted laser desorption ionization time-of-flight mass spectrometry and molecular methods improve the diagnosis. Actinomycetes are β-lactam susceptible, occasionally resistant. Treatment includes surgery and/or long-term parenteral then oral antibiotics, but some 1-4-week regimens or oral therapy alone were curative. For prophylaxis, oral hygiene and regular intrauterine device replacement are important.

Acne inversa complicated by Actinomyces neuii

INTRODUCTION

Acne inversa (AI) is a chronic and recurrent inflammatory skin disease. It occurs in intertriginous areas of the skin and causes pain, drainage, malodor and scar formation. While supposedly caused by an autoimmune reaction, bacterial superinfection is a secondary event in the disease process.

METHODS

A unique case of a 43-year-old male patient suffering from a recurring AI lesion in the left axilla was retrospectively analysed.

RESULTS

A swab revealed Actinomyces neuii as the only agent growing in the lesion. The patient was then treated with Amoxicillin/Clavulanic Acid 3 × 1 g until he was cleared for surgical excision. The intraoperative swab was negative for A. neuii. Antibiotics were prescribed for another 4 weeks and the patient has remained relapse free for more than 12 months now.

CONCLUSION

Primary cutaneous Actinomycosis is a rare entity and the combination of AI and Actinomycosis has never been reported before. Failure to detect superinfections of AI lesions with slow-growing pathogens like Actinomyces spp. might contribute to high recurrence rates after immunosuppressive therapy of AI. The present case underlines the potentially multifactorial pathogenesis of the disease and the importance of considering and treating potential infections before initiating immunosuppressive regimens for AI patients.

Actinomyces and related organisms in human infections

Actinomyces israelii has long been recognized as a causative agent of actinomycosis. During the past 3 decades, a large number of novel Actinomyces species have been described. Their detection and identification in clinical microbiology laboratories and recognition as pathogens in clinical settings can be challenging. With the introduction of advanced molecular methods, knowledge about their clinical relevance is gradually increasing, and the spectrum of diseases associated with Actinomyces and Actinomyces-like organisms is widening accordingly; for example, Actinomyces meyeri, Actinomyces neuii, and Actinomyces turicensis as well as Actinotignum (formerly Actinobaculum) schaalii are emerging as important causes of specific infections at various body sites. In the present review, we have gathered this information to provide a comprehensive and microbiologically consistent overview of the significance of Actinomyces and some closely related taxa in human infections.