Nasal carriage rate and associated risk factors of Staphylococcus lugdunensis isolated from healthy people in the Duhok-Kurdistan region of Iraq

Aims@#The aim of the study was to investigate the prevalence, antibiogram and associated risk factors of Staphylococcus lugdunensis among healthy people. @*Methodology and results@#A total of 200 nasal samples were collected from participants. The swabs were cultured on mannitol salt agar and incubated at 37 °C for 24 h. Isolates were diagnosed based on phenotypic, biochemical reactions and molecular methods. All identified isolates were screened for susceptibility to ten different antibiotics. Based on Gram stain and biochemical tests, 65 out of 200 (32.5%) were identified as S. lugdunensis. Twenty-nine of 65 (34.5%) were from males and 36 of 65 (31%) were from females (p=0.603). The highest prevalence was observed in the age group of 31-40 years (40%; 16/41) and the least prevalence rate was among the age group of ≥51 (15.4%; 2/13) (p=0.533). No statistically significant difference in the prevalence of S. lugdunensis was observed among people according to their family member size (p=0.472). Additionally, a slight difference in the carriage rate of S. lugdunensis was observed among the people who had Coronavirus disease (Covid-19) infection (31%) and the people who had no previous infection with it (33.6%) (p=0.697). Also, no statistically significant difference (p=0.992) in the nasal carriage rate of S. lugdunensis was observed among smokers (32.5%; 12/37) and nonsmokers (32.5%; 53/163). All isolates were 100% susceptible to doxycycline, linezolid and chloramphenicol; 99% to oxacillin; 92% to ciprofloxacin; 91% to amikacin; 89% to nitrofurans and vancomycin; 83% to meropenem; and 75% to erythromycin. Also, 15.4% of the isolates were multidrug resistant. @*Conclusion, significance and impact of study@#Results revealed that the prevalence of nasal S. lugdunensis was high among people with no specific associated risk factor. Also, a high rate of antibiotic resistance was observed with a high rate of multidrug resistance. Hence, education programs and improving hygienic measures are necessary to prevent the spread of multidrug resistance to S. lugdunensis. This can help as an effective measure to control bacterial infections

Infección por Staphylococcus lugdunensis: descripción de 44 casos / Staphylococcus lugdunensis infection: report of 44 cases

INTRODUCCIÓN: Staphylococcus lugdunensis, es un estafilococo coagulasa negativa (SCN) con características de virulencia y de sensibilidad antimicrobiana que lo hacen más parecido a Staphylococcus aureus que a otros SCN. OBJETIVOS: Conocer las características clínicomicrobiológicas de los aislados de S. lugdunensis identificados en nuestra institución. MATERIAL Y MÉTODOS: Se realizó un estudio retrospectivo de los aislados de S. lugdunensis entre los años 2017 y 2019 en el Servicio de Microbiología del Hospital Universitario San Jorge de Huesca (España). Se revisaron las historias clínicas correspondientes a los pacientes con aislamiento de S. lugdunensis, considerándose las siguientes variables: edad, sexo, tipo de muestra, servicio de procedencia y enfermedad de base. La identificación bacteriana se realizó con MALDI-TOF VITEK MS (BioMérieux, Francia). Así mismo, se estudió su patrón de susceptibilidad antimicrobiana in vitro mediante microdilución en placa. RESULTADOS: Se obtuvieron 44 aislados de S. lugdunensis: 12 procedían de heridas, 10 fueron abscesos, 8 úlceras, 7 orinas, 4 frotis cutáneos, 2 exudados óticos, y 1 exudado vaginal. En relación con la enfermedad de base destacaron cinco pacientes con procesos tumorales y diez con diabetes mellitus. En 17 pacientes existían antecedentes de cirugía o traumatismo reciente. La mayoría de las cepas fueron sensibles a los antimicrobianos estudiados. En 19 de ellas se observó producción de β-lactamasa, dos fueron resistentes a macrólidos y tres a clindamicina. Todas las cepas fueron sensibles a oxacilina, gentamicina y cotrimoxazol. CONCLUSIONES: Aunque S. lugdunensis mantiene una buena sensibilidad a la mayoría de los antimicrobianos, su tendencia a producir abscesos y que exprese factores de virulencia más parecido a S. aureus que a otros SCN, hace necesaria una correcta identificación en el laboratorio con el fin de que su incidencia no quede subestimada.

BACKGROUND: Staphylococcus lugdunensis is a coagulase-negative staphylococcus (CNS) with virulence and antibiotic sensitivity characteristics which makes it more similar to Staphylococcus aureus than other CNS. AIM: To know the microbiological and clinical characteristics of S. lugdunensis isolates identified from our health sector. METHODS: A retrospective study of S. lugdunensis isolates was carried out between 2017 and 2019 in the Microbiology Service of the San Jorge University Hospital in Huesca (Spain). The clinical records of patients with S. lugdunensis isolation were reviewed, considering the following factors: age, sex, sample type, service and underlying disease. Bacterial identification was performed using MALDI-TOF VITEK MS (BioMérieux, France). The pattern of antibiotic susceptibility was studied by means of plate microdilution. RESULTS: 44 isolates of S. lugdunensis were obtained: 12 corresponded to wounds, 10 were abscesses, 8 ulcers, 7 urine samples, 4 skin smears, 2 otic exudates, and 1 vaginal exudate. Regarding the underlying disease, five patients had a tumor processes and ten had diabetes mellitus. In 17 patients there was a history of recent surgery or trauma. Most of the strains were susceptible to the antibiotics studied. Production of beta-lactamase was observed in 19 of them, two were resistant to macrolides and three to clindamycin. None of the isolates were resistant to oxacillin, gentamicin or cotrimoxazole. CONCLUSIONS: Although S. lugdunensis maintains a good sensitivity to most antibiotics, its tendency to produce abscesses and that it expresses virulence factors more similar to S. aureus than to other CNS requires a correct identification in the laboratory so that its incidence is not underestimated.

Significación clínica y aspectos microbiológicos para el diagnóstico de pacientes con Staphylococcus lugdunensis / Clinical significance and microbiological aspects for the diagnosis of patients with Staphylococcus lugdunensis

El Staphylococcus lugdunensis se manifiesta más como Staphylococcus aureus que como un típico estafilococo coagulasa negativa, especialmente por su gran virulencia y capacidad para producir infecciones supuradas. Debido al protagonismo creciente de esta especie, es propósito de esta investigación destacar la significación clínica y los aspectos microbiológicos para el diagnóstico de pacientes con dicha infección.

The Staphylococcus lugdunensis is manifested more as Staphylococcus aureus that as a typical negative coagulase staphylococcus, especially for its great virulence and capacity to produce suppurated infections. Due to the growing protagonism of this species, this investigation aims at highlighting the clinical significance and microbiological aspects for the diagnosis of patients with this infection.

Staphylococcus lugdunensis endophthalmitis following dexamethasone intravitreal implant

We present a unique case of endophthalmitis with Staphylococcus lugdunensis following dexamethasone intravitreal implant for branch retinal vein occlusion associated with cystoid macular edema. Patient did not show favorable clinical response after vitrectomy and intravitreal antibiotics; so, we decided to repeat vitrectomy, remove the steroid implant and fill the eye with silicon oil, and repeat intravitreal vancomycin. Vision has improved from hand movements at presentation to counting fingers at 1.5 m after second vitrectomy and final visual acuity 3 months later after silicon oil removal was 6/36.

A Case of Infectious Arthritis due to Staphylococcus lugdunensis in Seronegative Rheumatoid Arthritis, Diabetes Mellitus Patient, after Intraarticular Hyaluronic Acid Injection

Intra-articular hyaluronic acid injections for symptomatic treatment of osteoarthritis are widely used but can result in complications, such as infectious arthritis. Staphylococcus lugdunensis is a common normal skin flora but can cause severe infectious disease, such as infective endocarditis. We present the first report of infectious arthritis caused by methicillin-sensitive S. lugdunensis after intra-articular hyaluronic acid injection in an immunocompromised patient in Korea.

A Case of Staphylococcus lugdunensis Endophthalmitis after Cataract Surgery

PURPOSE: To report a case of Staphylococcus lugdunensis endophthalmitis following cataract extraction and intraocular lens implantation. CASE SUMMARY: A 59-year-old woman presented with unilateral vision impairment and eyeball pain in her left eye, thirteen days after phacoemulsification and posterior chamber intraocular lens implantation. Best-corrected visual acuity of her left eye was 20/200. Slit lamp examination of her left eye revealed a severe conjunctival injection, severe chamber reactions with exudative membranes, hypopyon (about 1 mm) in the anterior chamber, and the fundus was not visible. Before the patient was admitted to the hospital, we cultured samples of aqueous fluid and performed an intravitreal antibiotics injection (vancomycin 1.0 mg/0.1 mL, ceftazidime 2.0 mg/0.1 mL). However, on the next day, because the inflammatory reactions of the anterior chamber and vitreous cavity were not improved and Gram positive cocci was confirmed, we performed a pars plana vitrectomy and an additional intravitreal antibiotics injection (vancomycin 1.0 mg/0.1 mL, dexamethasone 0.5 mg/0.1 mL). Seven days after the surgery, Staphylococcus lugdunensis was identified in the aqueous fluids culture. 11 days after the surgery, her inflammation and symptoms were improved and therefore, she could be discharged. Three months after the surgery, best-corrected visual acuity of her left eye was 20/20 and there was no evidence of recurrence of endophthalmitis and no abnormal findings in her fundus.

Septic Knee Arthritis Caused by Staphylococcus lugdunensis After Intraarticular Injection Therapy

Staphylococcus lugdunensis is a coagulase-negative staphylococcus. However, it causes various clinically important human infections and behaves similar to Staphylococcus aureus. S. lugdunensis reportedly causes infective endocarditis, skin and soft tissue infection, bone and joint infection, septicemia, endarteritis, urinary tract infection, ocular infection, and peritonitis. There are no reports of septic arthritis by this organism in Korea. We presented a case of septic arthritis due to S. lugdunensis in an elderly patient with diabetes mellitus after an intra-articular injection.

A Case of Psoas Abscess Caused by Staphylococcus lugdunensis / 대한내과학회지

Staphylococcus lugdunensis is a member of coagulase-negative staphylococci (CoNS), an uncommon microbial culture isolate with virulent potency. Although CoNS are common skin commensals, and often regarded as contaminants or colonizers when isolated from clinical specimen cultures, the clinical course and microbiological characteristics of Staphylococcus lugdunensis may resemble those of Staphylococcus aureus rather than other CoNS. Invasive infectious diseases such as infective endocarditis, peritonitis, skin and soft tissue infection, vascular prosthetic infection, septicemia, and osteomyelitis have been found to be associated with Staphylococcus lugdunensis. Here we report the first case of psoas abscess caused by methicillin-sensitive Staphylococcus lugdunensis in Korea.

A Case of Botryomycosis Caused by Staphylococcus lugdunensis in a Chronic Alcoholic / 대한피부과학회지

Botryomycosis is a chronic bacterial granulomatous and suppurative disease, which may be similar to the fungal disease, clinically and histologically. It is commonly caused by Staphylococcus aureus, but Pseudomonas aeruginosa, Escherichia coli, and Proteus spp. have been rarely involved. The known predisposing factors are trauma, postoperative complication, diabetes mellitus, chronic alcoholic, and so on. We present the botryomycosis caused by Staphylococcus lugdunensis, which is a rare virulent pathogen of botryomycosis, in a chronic alcoholic.

Staphylococcus lugdunensis: um olhar diferenciado no laboratório clínico / Staphylococcus lugdunensis: a different view in the clinical laboratory

Os estafilococos coagulase negativos (ECNs) são cocos Gram-positivos usualmente considerados contaminantes em laboratórios de microbiologia clínica. Apesar de pertencer a este grupo, Staphylococcus lugdunensis pode causar infecções complicadas, como endocardites, infecções de pele e tecidos moles, osteomielites, entre outras. Além da formação de biofilmes, apresenta patogenicidade similar ao Staphylococcus aureus. É um dos principais agentes causadores de endocardites, com taxa de mortalidade de até 70 por cento. Pode ser confundido com S. aureus quando se utilizam testes rápidos para sua identificação, como a pesquisa de clumping factor, no caso de teste de coagulase em lâmina, ou em testes de aglutinação direta em látex. Pode ser facilmente identificado por meio de provas bioquímicas acessíveis, como a presença de atividade da ornitina descarboxilase e pirrolidonil arilamidase (PYR). Apresenta sensibilidade à maioria dos agentes antimicrobianos, devendo ser pesquisada rotineiramente a presença de betalactamases e do gene mecA por meio de testes com cefalosporina cromogênica e suscetibilidade à cefoxitina, respectivamente. Convém salientar que os critérios interpretativos utilizados para avaliar a sensibilidade à cefoxitina são os mesmos preconizados para S. aureus e diferentes dos utilizados para os outros ECNs. Apesar de incomum, o S. lugdunensis é um patógeno com acentuada virulência que deve ser corretamente identificado, pois raramente poderá ser considerado contaminante quando isolado de sítios estéreis.

Coagulase-negatives staphylococci (CNS) are Gram-positives cocci commonly regarded as contaminants in clinical microbiology laboratories. Despite belonging to this group, Staphylococcus lugdunensis may cause complicated infections such as endocarditis, skin infections and soft tissue, osteomyelitis, among others. Apart from the formation of biofilms, it has pathogenic features similar to Staphylococcus aureus. It may be mistakenly identified as S. aureus when using rapid identification tests, such as clumping factor in slide coagulase or in agglutination latex tests. It is easily identified through available biochemical tests, such as the presence of ornithine decarboxylase and pyrrolidonyl arylamidase (PYR). It presents sensitivity to most antimicrobial agents. Furthermore, the presence of beta-lactamase and mecA gene should be routinely investigated by testing with chromogenic cephalosporin and cefoxitin susceptibility, respectively. It is convenient to highlight that the interpretative criteria used to evaluate cefoxitin sensitivity are the same recommended for S. aureus and different from those used for other CNS. Despite the fact it is atypical, S. lugdunensis is a virulent pathogen, which must be accurately identified insofar as it will rarely be deemed as a contaminant when isolated from sterile sites.

A Case of Native Valve Infective Endocarditis Caused by Staphylococcus lugdunensis / 대한내과학회지

A 37-year-old woman presented to our hospital with a 1-month history of fever. She also complained of lower leg pain. Transthoracic echocardiography showed large vegetations on the mitral valve leaflets. Staphylococcus lugdunensis was isolated from blood cultures. She was diagnosed with infectious endocarditis due to S. lugdunensis and was treated with antibiotics and surgery. Infective endocarditis caused by S. lugdunensis can be invasive and often resembles endocarditis due to Staphylococcus aureus. Thus, whenever this organism is found in patients with endocarditis, early surgical treatment of the infected valve should be considered.

A Case of Pulmonary Artery Endarteritis due to Staphylococcus lugdunensis in Patient with Clinically Silent Patent Ductus Arteriosus / 이화의대지

Staphylococcus lugdunensis (S. lugdunensis) is an unusually virulent coagulase-negative staphylococci (CNS) and uncommon cause of infective endocarditis (IE) involving mainly native left sided valves. S. lugdunensis IE, which was described previously as "surreptitious" and "wolf in sheep's clothing", runs an aggressive course with a high rate of severe in-hospital complications. Therefore, early surgical treatment has been considered for the treatment of S. lugdunensis IE. However, we experienced a case of S. lugdunensis pulmonary endarteritis which was cured with antibiotic therapy alone.

Native Valve Infective Endocarditis due to Staphylococcus lugdunensis Confirmed by 16S Ribosomal RNA Sequencing / 감염과화학요법

Staphylococcus lugdunensis is a Gram-positive, coagulase-negative Staphylococcus (CNS) species that is found as a skin commensal and has been implicated in fulminant invasive diseases such as infective endocarditis. S. lugudunensis infections resemble Staphylococcus aureus infections in terms of virulence, tissue destruction and clinical course. Although correct identification and determination of the susceptibility profile are important, some commercial systems may misidentify S. lugdunensis. We report a case of native valve infective endocarditis caused by S. lugdunensis, which was misidentified by the Vitek 2 system but identified correctly by 16S ribosomal RNA (rRNA) gene sequencing in a 72-year-old male patient. The patient had multiple vegetations on his mitral valve, and the largest one was found on the posterior mitral valve leaflet. It was 2.5 cm in size and hypermobile. Diffuse valvular abscess was also observed. He had persistent bacteremia for appoximately 8 days, which was resolved after immediate surgery and antibiotic therapy. When a patient with severe sepsis syndrome grows S. aureus or CNS other than S. lugdunensis on a commercial automatic culture system, the possibility of S. lugdunensis should be considered and further confirmatory testing such as 16S rRNA sequencing may be very useful.

Acute Lymphadenitis with Cellulitis Caused by Staphylococcus lugdunensis / 대한진단검사의학회지

Although coagulase-negative staphylococci (CNS) have been considered part of the resident flora on the human skin, Staphylococcus lugdunensis is an unusually virulent CNS and can cause many types of infection. We report a rare case of acute lymphadenitis with cellulitis in the right infraauricular region caused by S. lugdunensis. A 62-yr-old woman visited the Department of Otolaryngology of Busan Paik university hospital. She had a palpable mass and swelling in the right infraauricular region and complained of aggressive pain and a febrile sensation in the region for 5 days. On the suspicion of abscess with infection, percutaneous aspiration was performed and smooth, flat, white, opaque colonies grew on a blood agar plate as a pure culture. The biochemical test results showed the organism to be catalase positive, tube coagulase negative, ornithine decarboxylase positive, slide coagulase positive, and latex agglutination tests for coagulase positive. The API Staph Kit was used to identify the isolate to the species level as S. lugdunensis with a 64.6% probability (profile 6716152). We confirmed the species identification of this strain by 16S rDNA sequence analysis. The patient's clinical condition improved with appropriate antimicrobial therapy and pus drainage.

A Case of Septicemia by Staphylococcus lugdunensis / 대한임상미생물학회지

Staphylococcus lugdunensis is one of coagulase-negative staphylococci, but rarely causes aggressive and progressive infections similar to Staphylococcus aureus infection. Moreover, agglutination test for clumping factor can be positive, and the colony morphology often resembles that of S. aureus, but S. lugdunensis is usually sensitive to all antimicrobials used against staphylococci. We report a case of septicemia caused by S. lugdunensis in a 71-year-old man with diarrhea, diabetes mellitus, and peripheral neuropathy.

A Case of Infective Endocarditis due to Staphylococcus lugdunensis / 감염과화학요법

Staphylococcus lugdunensis is a coagulase-negative staphylococcus (CNS) that is commonly found on the human perineal skin. Contrary to other CNS, S. lugdunensis is a rare contaminant in cultures and has the potential to cause clinically significant infections, including infective endocarditis. Infective endocarditis due to S. lugdunensis have been known to resemble endocarditis due to S. aureus because of its aggressive clinical course and high mortality. We report a case of infective endocarditis caused by S. lugdunensis in a 21-year-old woman. She was cured of the infection with surgical and antibiotic therapy.

A Case of Infective Endocarditis due to Staphylococcus lugdunensis / 감염과화학요법

Staphylococcus lugdunensis is a coagulase-negative staphylococcus (CNS) that is commonly found on the human perineal skin. Contrary to other CNS, S. lugdunensis is a rare contaminant in cultures and has the potential to cause clinically significant infections, including infective endocarditis. Infective endocarditis due to S. lugdunensis have been known to resemble endocarditis due to S. aureus because of its aggressive clinical course and high mortality. We report a case of infective endocarditis caused by S. lugdunensis in a 21-year-old woman. She was cured of the infection with surgical and antibiotic therapy.

Two cases of S. lugdunensis Isolated from Blood and Venous Catheter / 대한임상미생물학회지

Staphylococcus lugdunensis is a member of the coagulase negative staphylococci (CoNS) which has been associated with serious infections in humans. Species identification of S. lugdunensis isolates should be done but they may be misidentified as other CoNS species or Staphylococcus aureus due to positivity for clumping factor. We report the first two cases of catalase-positive and Gram positive cocci isolated from blood and venous catheter, which were positive for latex agglutination coagulase test but susceptible to penicillin, negative for tube coagulase test and negative acid production from mannitol and finally identified as S. lugdunensis.