Acne inversa complicated by Actinomyces neuii

The Clinical Relevance of the Microbiome in Hidradenitis Suppurativa: A Systematic Review

Hidradenitis suppurativa is a chronic disease of the pilosebaceous unit. The name of the condition is a testament to the presumed relationship between the disease and the microbiome. The pathophysiology of hidradenitis suppurativa is, however, complex and believed to be the product of a multifactorial interplay between the interfollicular epithelium, pilosebaceous unit, microbiome, as well as genetic and environmental factors. In this review we assimilate the existing literature regarding the role played by the human microbiome in HS in various contexts of the disease, including the pathophysiologic, therapeutic, and potentially, diagnostic as well prognostic. In conclusion, the role played by the microbiome in HS is extensive and relevant and can have bench-to-bedside applications.

Antimicrobial treatment of Acinetobacter neuii invasive infections: A systematic review

Aims: The objectives of this study were to find out whether and to what extent Actinomyces neuii is pathogenic to humans in terms of causing invasive infections and to ascertain the most appropriate and effective antibiotic therapy against this bacterium. Material and method: This study was designed as a systematic review article. MEDLINE, Google Scholar, SCIndex, Cochrane database of published clinical trials - Central and Clinicaltrials.gov databases were systematically searched for primary case reports or case series describing invasive infection with Actinomyces neuii. Results: A literature search identified 23 studies that met the inclusion criteria, describing cases of patients with an invasive infection caused by Actinomyces neuii. It was found that A. neuii could cause endocarditis, endophthalmitis, osteomyelitis, pleural empyema, soft tissue abscesses, neonatal sepsis, ventriculoperitoneal shunt infections and periprosthetic tissue infections. The most prescribed antibiotics for the treatment of Actinomyces neuii infections were amoxicillin and vancomycin (n = 10; 12.3%), followed by penicillin (n =9; 11.1%), gentamicin (n = 6; 7.4%), ampicillin (n = 5; 6.2%) and ceftazidime (n = 4; 4.9%). Antibiotic treatment of infections caused by A. neuii was followed by clinical improvement or complete cure of all patients, with no recorded deaths. Conclusion: A. neuii has a relevant pathogenic potential to cause invasive infections of various organs and tissues, especially in immunocompromised individuals of any age. For the treatment of mild infections caused by this bacterium, the antibiotics of choice are penicillin or amoxicillin, while vancomycin should be used to treat severe infections caused by Actinomyces neuii.

North American clinical management guidelines for hidradenitis suppurativa: A publication from the United States and Canadian Hidradenitis Suppurativa Foundations: Part I: Diagnosis, evaluation, and the use of complementary and procedural management

Hidradenitis suppurativa is a chronic inflammatory disorder affecting hair follicles, with profoundly negative impact on patient quality of life. Evidence informing ideal evaluation and management of patients with hidradenitis suppurativa is still sparse in many areas, but it has grown substantially in the last decade. Part I of this evidence-based guideline is presented to support health care practitioners as they select optimal management strategies, including diagnostic testing, comorbidity screening, and both complementary and procedural treatment options. Recommendations and evidence grading based on the evidence available at the time of the review are provided.

Hidradenitis suppurativa, neutrophilic dermatoses and diverticular disease in a young African-American patient

Hidradenitis suppurativa (HS) is a chronic skin disorder of the terminal follicular epithelium of apocrine sweat glands, manifesting as painful and exudative papules, pustules, cysts or nodules. This inflammatory condition often presents with other systemic and cutaneous disorders. We present the case of an African-American man with HS who was also diagnosed with neutrophilic dermatoses and diverticular disease. Neutrophilic dermatosis was identified based on histopathology findings. Our patient underwent multiple surgeries for flaring of his skin condition. Colchicine and doxycycline were started, but the patient was not able to tolerate them. Humira was planned for treatment of HS and neutrophilic dermatosis but could not be pursued because of the pericolic abscess. Colonoscopy and radiological investigation revealed multiple colonic diverticuli, for which he initially underwent percutaneous drainage followed by surgical removal of sigmoid mass and colocutaneous fistula. Culture from the specimen revealed abnormal growth of Actinomyces.

The association of medication-related osteonecrosis of the jaw with Actinomyces spp. infection

Medication-related osteonecrosis of the jaw (MRONJ) represents a complication of bisphosphonate treatment that responds poorly to standard treatment. In a retrospective cohort study we investigated a possible role of Actinomyces spp. in the pathogenesis of MRONJ. Deep biopsies of necrotic bone were collected during surgical treatment of MRONJ and evaluated by histology and microbiology for the presence of Actinomyces spp. Microbiological, demographic and clinicpathological data were analyzed for risk of Actinomyces-associated MRONJ. Between 2005 and 2014, 111 patients suffering from histologically-confirmed MRONJ were identified. Actinomyces spp. were detected in 99 cases (89%) by histology and in six further patients by microbiological culture. A diverse microbial flora was found in all specimens without association with Actinomyces spp. Demographic and clinicopathological characteristics did not separate significantly Actinomyces-positive from Actinomyces-negative cases. Our observations confirm previous reports of a high prevalence of Actinomyces spp. in MRONJ in the single largest cohort available up to now. The high prevalence of Actinomyces spp. and the lack of clinicopathological risk factors underline the prominent role of Actinomyces spp. in MRONJ and may change the current understanding of MRONJ. Established prolonged antimicrobial treatment regimens against Actinomyces spp. infection could therefore be a mainstay of future MRONJ management.

Resistance patterns in clinical isolates of pathogenic Actinomyces species

OBJECTIVES

Actinomyces spp. are commensals that may occasionally invade deep tissue structures, causing difficult-to-treat and disfiguring lesions. Information on antimicrobial resistance patterns is limited to observations from two previous studies. Therefore, we examined antimicrobial resistance patterns in clinical isolates of Actinomyces spp.

METHODS

In this retrospective assessment of antimicrobial resistance patterns, we identified 392 Actinomyces spp. at a tertiary care centre from January 2008 to December 2014. MICs of various antimicrobial agents, including ampicillin/sulbactam, meropenem, clindamycin, metronidazole and vancomycin for anaerobic actinomycetes, were obtained by Etest. For aerobic actinomycetes, imipenem, cefotaxime, amikacin, linezolid, moxifloxacin, trimethoprim/sulfamethoxazole and clarithromycin were tested. MIC results were interpreted based on guidelines published by the CLSI (formerly NCCLS).

RESULTS

Actinomyces meyeri was predominantly isolated and accounted for 34% of all Actinomyces spp. identified, followed by Actinomyces turicensis with 23%. Actinomyces neuii is considered to be a rare Actinomyces sp., but accounted for 8% of isolates. Antimicrobial susceptibility testing of isolates showed that the Actinomyces spp. were almost uniformly susceptible to β-lactam antimicrobials (with and without β-lactamase inhibitors), carbapenems, tetracyclines and vancomycin. In contrast, Actinomyces spp. isolates were almost uniformly resistant to metronidazole.

CONCLUSIONS

β-Lactam antimicrobial agents remain the first choice, whereas metronidazole should be avoided, in the treatment of actinomycosis. Reasonable alternatives for treatment are tetracyclines and carbapenems.