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2.
Pan Afr Med J ; 36: 234, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33708325

RESUMO

The fungal nasal septum abscess is a rare localized invasive form of fungal rhinosinusitis. Rare cases have been described in the literature. In this article, we intend to describe a new case of fungal nasal septum abscess caused by Aspergillus flavus in diabetic patient after sinonasal surgery. A 53-year-old woman with a history of uncontrolled type 2 diabetes and asthma developed a nasal septum abscess after a sinonasal endoscopic surgery which was performed for nasal polyposis. Needle aspiration of the abscess was performed and the pus cultures were positive for Aspergillus flavus. The patient was treated with antifungal drugs and surgical drainage of the abscess. A clinical and biological improvement was observed. Her case has been followed up for 18 months, and there hasn't been any recurrence of the infection. The fungal nasal septum abscess should be suspected in patients who do not respond adequately to standard treatment of nasal septum abscess, especially patients with risk factors of fungal rhinosinusitis.


Assuntos
Abscesso/diagnóstico , Aspergilose/diagnóstico , Aspergillus flavus/isolamento & purificação , Septo Nasal/microbiologia , Abscesso/microbiologia , Antifúngicos/administração & dosagem , Aspergilose/microbiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Pessoa de Meia-Idade , Pólipos Nasais/microbiologia , Pólipos Nasais/cirurgia , Rinite/diagnóstico , Rinite/microbiologia , Sinusite/diagnóstico , Sinusite/microbiologia
5.
BMJ Case Rep ; 12(7)2019 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-31352375

RESUMO

We report the clinical case of a female patient who presented to our emergency department due to a septal abscess caused by the displacement of a dental implant into the nasal septum. The patient underwent surgical treatment for endoscopic foreign body excision and septal abscess drainage. Despite the presence of septal cartilage destruction, the L-shaped structure was preserved and no reconstruction was required. Postoperative healing was uneventful.


Assuntos
Implantes Dentários , Obstrução Nasal/cirurgia , Septo Nasal/cirurgia , Doenças Nasais/cirurgia , Complicações Pós-Operatórias/cirurgia , Abscesso/etiologia , Adulto , Antibacterianos/uso terapêutico , Implantes Dentários/efeitos adversos , Drenagem , Feminino , Migração de Corpo Estranho , Humanos , Obstrução Nasal/diagnóstico por imagem , Obstrução Nasal/etiologia , Septo Nasal/diagnóstico por imagem , Septo Nasal/microbiologia , Doenças Nasais/diagnóstico por imagem , Doenças Nasais/microbiologia , Complicações Pós-Operatórias/diagnóstico por imagem , Resultado do Tratamento
6.
PLoS Negl Trop Dis ; 13(3): e0006704, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30835734

RESUMO

Leprosy is a chronic infection where the skin and peripheral nervous system is invaded by Mycobacterium leprae. The infection mechanism remains unknown in part because culture methods have not been established yet for M. leprae. Mce1A protein (442 aa) is coded by mce1A (1326 bp) of M. leprae. The Mce1A homolog in Mycobacterium tuberculosis is known to be associated with M. tuberculosis epithelial cell entry, and survival and multiplication within macrophages. Studies using recombinant proteins have indicated that Mce1A of M. leprae is also associated with epithelial cell entry. This study is aimed at identifying particular sequences within Mce1A associated with M. leprae epithelial cell entry. Recombinant proteins having N-terminus and C-terminus truncations of the Mce1A region of M. leprae were created in Escherichia coli. Entry activity of latex beads, coated with these truncated proteins (r-lep37 kDa and r-lep27 kDa), into HeLa cells was observed by electron microscopy. The entry activity was preserved even when 315 bp (105 aa) and 922 bp (308 aa) was truncated from the N-terminus and C-terminus, respectively. This 316-921 bp region was divided into three sub-regions: 316-531 bp (InvX), 532-753 bp (InvY), and 754-921 bp (InvZ). Each sub-region was cloned into an AIDA vector and expressed on the surface of E. coli. Entry of these E. coli into monolayer-cultured HeLa and RPMI2650 cells was observed by electron microscopy. Only E. coli harboring the InvX sub-region exhibited cell entry. InvX was further divided into 4 domains, InvXa-InvXd, containing sequences 1-24 aa, 25-46 aa, 47-57 aa, and 58-72 aa, respectively. Recombinant E. coli, expressing each of InvXa-InvXd on the surface, were treated with antibodies against these domains, then added to monolayer cultured RPMI cells. The effectiveness of these antibodies in preventing cell entry was studied by colony counting. Entry activity was suppressed by antibodies against InvXa, InvXb, and InvXd. This suggests that these three InvX domains of Mce1A are important for M. leprae invasion into nasal epithelial cells.


Assuntos
Proteínas de Bactérias/metabolismo , Hanseníase/microbiologia , Mycobacterium leprae/patogenicidade , Septo Nasal/microbiologia , Proteínas de Bactérias/genética , Linhagem Celular , Contagem de Colônia Microbiana , DNA Bacteriano/genética , Escherichia coli/genética , Vetores Genéticos/genética , Células HeLa , Humanos , Microesferas , Mycobacterium leprae/genética , Mycobacterium leprae/crescimento & desenvolvimento , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
7.
Eur Arch Otorhinolaryngol ; 276(2): 417-420, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30506184

RESUMO

OBJECTIVE: Nasal septal abscess is an uncommon condition but it can cause potentially life-threatening intracranial complications and cosmetic nasal deformity. METHODS: We analyzed ten years of cases to determine the optimal diagnostic and therapeutic modalities. A retrospective review of case notes from Tri-Service General Hospital archives was performed. Records of six patients diagnosed with nasal septal abscess, who were treated from September 2007 to August 2017 were retrospectively reviewed. Patients' clinical symptoms, etiology, diagnostic methods, bacteriology, antibiotic and surgical treatment were recorded and analyzed. RESULTS: Out of six patients diagnosed with nasal septal abscess, three were male and three were female. Ages ranged from 19 to 75 years (mean 51 years). The most common symptoms at presentation were nasal pain and nasal obstruction. Typical etiologies were trauma or acute sinusitis, but uncontrolled diabetes mellitus was also an important etiology. In the series of six patients, four of them had positive findings of abscess and in drainage, had the following bacterial cultures: Staphylococcus aureus (two cases), methicillin-resistant S. aureus (one case), and Klebsiella pneumoniae (one case). In addition to antibiotic treatment, all patients underwent surgical drainage and had complete resolution of disease without intracranial complications during at least 1 year of follow-up. However, two out of the six patients developed saddle nose deformity. CONCLUSIONS: This study highlights that: 1. In view of the rapidly increasing number of diabetes mellitus cases, uncontrolled diabetes mellitus is an important etiology of nasal septal abscess. 2. Although S. aureus is the most common pathogen, we must pay attention to methicillin-resistant S. aureus (MRSA) to prevent severe complications and patients who are at increased risk for MRSA colonization should be administrated antibiotics against MRSA initially. 3. Nasal septal abscess should be managed with parenteral broad spectrum antibiotics, appropriate drainage and immediate reconstruction of the destructed septal cartilage with autologous cartilage graft, to prevent serious intracranial complications and cosmetic nasal deformity.


Assuntos
Abscesso/diagnóstico , Abscesso/terapia , Septo Nasal/lesões , Septo Nasal/microbiologia , Abscesso/etiologia , Adulto , Idoso , Antibacterianos/uso terapêutico , Complicações do Diabetes , Drenagem , Feminino , Humanos , Klebsiella pneumoniae/isolamento & purificação , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Pessoa de Meia-Idade , Obstrução Nasal/etiologia , Deformidades Adquiridas Nasais/etiologia , Dor/etiologia , Estudos Retrospectivos , Sinusite/complicações , Staphylococcus aureus/isolamento & purificação , Adulto Jovem
9.
Pan Afr Med J ; 31: 247, 2018.
Artigo em Francês | MEDLINE | ID: mdl-31448004

RESUMO

We report the case of a 80-year old hypertensive female patient, presenting with bilateral nasal obstruction not improved by symptomatic treatment. The examination of the nasal cavity showed pseudotumoral hypervascularized granulomatous bleeding lesion on both sides of the anterior portion of the nasal septum (A). The remainder of the septal mucosa showed granulomatous appearance. CT scan of the facial bones showed tissue lesion of the nasal cavities on both sides of the septum which was moderately enhancing after injection of iodinated contrast medium (ICM), without bone lysis (B). Biopsy showed rhinoscleroma. The patient received combination therapy including cyclin associated with cotrimoxazole without disappearance of the nasal lesion. Endonasal excision of the septal mass was performed. Histological examination confirmed the diagnosis of rhinoscleroma. The patient underwent ciprofloxacin therapy for 1 month. Patient evolution was good with nasal clearance at 1-year follow up. Rhinoscleroma is a granulomatous infection of the nasal cavities due to enteric bacterium belonging to the Klebsiella family (Klebsiella rhinoscleromatis). Treatment is essentially medical. Surgery is used to remove obstructive pseudotumoral lesions resistant to medical treatment.


Assuntos
Ciprofloxacina/administração & dosagem , Cavidade Nasal/microbiologia , Obstrução Nasal/diagnóstico , Rinoscleroma/diagnóstico , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Biópsia , Feminino , Humanos , Klebsiella pneumoniae/isolamento & purificação , Cavidade Nasal/patologia , Obstrução Nasal/tratamento farmacológico , Obstrução Nasal/microbiologia , Septo Nasal/microbiologia , Septo Nasal/patologia , Rinoscleroma/tratamento farmacológico , Tomografia Computadorizada por Raios X
10.
BMC Infect Dis ; 17(1): 649, 2017 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-28950832

RESUMO

BACKGROUND: Orbital apex syndrome is a localized type of orbital cellulitis, where mass lesions occur at the apex of the cranial nerves. Although nasal septal abscess is uncommon, the organism most likely to cause nasal septal abscess is Staphylococcus aureus, and fungal septal abscesses are rare. Here we present an extremely rare and serious case of orbital apex syndrome secondary to fungal nasal septal abscess caused by Scedosporium apiospermum in a patient with uncontrolled diabetes. CASE PRESENTATION: A 59-year-old man with a 1-month history of headache underwent consultation in an otolaryngological clinic of a general hospital. He was diagnosed with nasal septal abscess and was treated with incisional drainage and 1 month of an antibiotic drip; however, his symptoms persisted. The patient later complained of diplopia due to bilateral abducens nerve palsy, and was then referred to the department of Otolaryngology - Head and Neck Surgery, Kobe City Medical Center General Hospital. The septal lesion was biopsied under general anesthesia, and S. apiospermum was detected using polymerase chain reaction. The patient was treated with an antifungal drug and surgical resection of the lesion was performed. Although the patient survived, he lost his eyesight. CONCLUSIONS: This patient represents the second reported case of nasal septal abscess and orbital apex syndrome caused by S. apiospermum. If not treated properly, septal abscess can be life-threatening and cause severe complications, such as ablepsia.


Assuntos
Micoses/etiologia , Doenças Nasais/etiologia , Doenças Orbitárias/etiologia , Scedosporium/patogenicidade , Abscesso/tratamento farmacológico , Abscesso/terapia , Antifúngicos/uso terapêutico , Diabetes Mellitus/microbiologia , Drenagem , Humanos , Masculino , Pessoa de Meia-Idade , Micoses/terapia , Septo Nasal/microbiologia , Doenças Nasais/terapia , Doenças Orbitárias/terapia
11.
Eur Arch Otorhinolaryngol ; 274(5): 2189-2195, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28220309

RESUMO

Although effects of Merocel® nasal packs and silicone splints on nasal flora alterations and bacteremia formation after septoplasty were assessed before, the effect of transseptal suturing technique has not been studied yet. The objective of this study is to compare nasal flora alterations and bacteremia occurrence rates between Merocel packs, silicone splints, and transseptal suturing technique in septoplasty. Ninety patients were divided into three groups randomly: Merocel packing (Group M), silicone splint (Group S), and transseptal suturing without packing (Group T). Group M and S received prophylactic antibiotics and antibiotic pomade application to packs, whereas neither antibiotic prophylaxis nor topical pomade was applied to Group T. Preoperative, after pack removal and 1 month after pack removal nasal swab cultures and preoperative, immediately after surgery and 24 h after surgery blood cultures were taken from all patients. Group M increased Methicillin-sensitive Staphylococcus aureus (MSSA) colonization (p = 0.003) and decreased normal flora colonization (p = 0.038), whereas Group S and T did not affect MSSA or normal flora colonization (p > 0.05). Antibiotic prophylaxis did not affect MSSA colonization (p = 0.14), whereas decreased normal flora colonization (p = 0.029). Transseptal suturing did not prevent bacteremia formation. Postoperative increasing of MSSA colonization in nasal cavity for septoplasty patients can be prevented by using transseptal suturing technique or silicone splints instead of Merocel packing, rather than applying prophylactic antibiotic treatment. Using transseptal suturing does not prevent bacteremia formation during septal surgery. These findings should be kept in mind to prevent postoperative life-threatening infective complications of septoplasty especially in immunosuppressive patients and patients with cardiovascular diseases.


Assuntos
Antibioticoprofilaxia , Bacteriemia/prevenção & controle , Infecção Hospitalar/prevenção & controle , Cavidade Nasal/microbiologia , Septo Nasal/cirurgia , Técnicas de Sutura , Adulto , Antibacterianos/uso terapêutico , Bactérias/isolamento & purificação , Sangue/microbiologia , Feminino , Formaldeído , Humanos , Masculino , Pessoa de Meia-Idade , Septo Nasal/microbiologia , Álcool de Polivinil , Complicações Pós-Operatórias/prevenção & controle , Rinoplastia/métodos , Staphylococcus aureus/isolamento & purificação
12.
Infect Immun ; 84(10): 2922-32, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27481242

RESUMO

Streptococcus pneumoniae is an opportunistic pathogen that colonizes the nasopharynx. Herein we show that carbon availability is distinct between the nasopharynx and bloodstream of adult humans: glucose is absent from the nasopharynx, whereas galactose is abundant. We demonstrate that pneumococcal neuraminidase A (NanA), which cleaves terminal sialic acid residues from host glycoproteins, exposed galactose on the surface of septal epithelial cells, thereby increasing its availability during colonization. We observed that S. pneumoniae mutants deficient in NanA and ß-galactosidase A (BgaA) failed to form biofilms in vivo despite normal biofilm-forming abilities in vitro Subsequently, we observed that glucose, sucrose, and fructose were inhibitory for biofilm formation, whereas galactose, lactose, and low concentrations of sialic acid were permissive. Together these findings suggested that the genes involved in biofilm formation were under some form of carbon catabolite repression (CCR), a regulatory network in which genes involved in the uptake and metabolism of less-preferred sugars are silenced during growth with preferred sugars. Supporting this notion, we observed that a mutant deficient in pyruvate oxidase, which converts pyruvate to acetyl-phosphate under non-CCR-inducing growth conditions, was unable to form biofilms. Subsequent comparative transcriptome sequencing (RNA-seq) analyses of planktonic and biofilm-grown pneumococci showed that metabolic pathways involving the conversion of pyruvate to acetyl-phosphate and subsequently leading to fatty acid biosynthesis were consistently upregulated during diverse biofilm growth conditions. We conclude that carbon availability in the nasopharynx impacts pneumococcal biofilm formation in vivo Additionally, biofilm formation involves metabolic pathways not previously appreciated to play an important role.


Assuntos
Biofilmes/crescimento & desenvolvimento , Metabolismo dos Carboidratos/fisiologia , Carboidratos/farmacologia , Galactose/farmacocinética , Neuraminidase/fisiologia , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/fisiologia , Análise de Variância , Animais , Biofilmes/efeitos dos fármacos , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Feminino , Galactose/metabolismo , Galactose/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Ácido N-Acetilneuramínico/metabolismo , Líquido da Lavagem Nasal/química , Septo Nasal/metabolismo , Septo Nasal/microbiologia , Nasofaringe/metabolismo , Nasofaringe/microbiologia , Neuraminidase/metabolismo , Infecções Pneumocócicas/metabolismo , Streptococcus pneumoniae/efeitos dos fármacos , beta-Galactosidase/deficiência , beta-Galactosidase/metabolismo
13.
J Coll Physicians Surg Pak ; 26(7): 626-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27504559

RESUMO

Pneumocephalus is collection of gas or air within the cranial cavity, commonly associated with trauma, cranial surgery, air embolism, open meningomyelocele; and rarely as a result of central nervous system infections. Asymptomatic pneumocephalus usually recovers spontaneously within few days. Untreated pneumocephalus can progress to tension pneumocephalus, manifesting as severe headache, dizziness, cranial nerve palsy, mental changes, seizure and disorientation. Herein, we report a rare case of pneumocephalus in a 9-month infant with subdural effusion following infection of nasal septum and otomastoiditis. There was no sign of meningitis but CThead showed communication of intracranial dura mater across widened foramen caecum with pre-nasal space, and bilateral otomastoiditis with erosion of anterior and lateral wall of right mastoid bone. The patient was treated successfully and discharged without sequelae.


Assuntos
Antibacterianos/administração & dosagem , Mastoidite/tratamento farmacológico , Septo Nasal/microbiologia , Otite Média/tratamento farmacológico , Pneumocefalia/microbiologia , Infecções por Pseudomonas/tratamento farmacológico , Amicacina/administração & dosagem , Humanos , Lactente , Masculino , Mastoidite/microbiologia , Septo Nasal/diagnóstico por imagem , Otite Média/microbiologia , Ácido Penicilânico/administração & dosagem , Ácido Penicilânico/análogos & derivados , Piperacilina/administração & dosagem , Pneumocefalia/diagnóstico por imagem , Infecções por Pseudomonas/diagnóstico , Derrame Subdural , Tazobactam , Tomografia Computadorizada por Raios X , Resultado do Tratamento
14.
Infect Control Hosp Epidemiol ; 37(10): 1147-55, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27426423

RESUMO

BACKGROUND Since the first isolation of Middle East respiratory syndrome coronavirus (MERS-CoV) in Saudi Arabia in 2012, sporadic cases, clusters, and sometimes large outbreaks have been reported. OBJECTIVE To describe the recent (2015) MERS-CoV outbreak at a large tertiary care hospital in Riyadh, Saudi Arabia. METHODS We conducted an epidemiologic outbreak investigation, including case finding and contact tracing and screening. MERS-CoV cases were categorized as suspected, probable, and confirmed. A confirmed case was defined as positive reverse transcription polymerase chain reaction test for MERS-CoV. RESULTS Of the 130 suspected cases, 81 (62%) were confirmed and 49 (38%) were probable. These included 87 patients (67%) and 43 healthcare workers (33%). Older age (mean [SD], 64.4 [18.3] vs 40.1 [11.3] years, P<.001), symptoms (97% vs 58%, P<.001), and comorbidity (99% vs 42%, P<.001) were more common in patients than healthcare workers. Almost all patients (97%) were hospitalized whereas most healthcare workers (72%) were home isolated. Among 96 hospitalized cases, 63 (66%) required intensive care unit management and 60 (63%) required mechanical ventilation. Among all 130 cases, 51 (39%) died; all were patients (51 [59%]) with no deaths among healthcare workers. More than half (54%) of infections were believed to be caught at the emergency department. Strict infection control measures, including isolation and closure of the emergency department, were implemented to interrupt the chain of transmission and end the outbreak. CONCLUSION MERS-CoV remains a major healthcare threat. Early recognition of cases and rapid implementation of infection control measures are necessary. Infect Control Hosp Epidemiol 2016;1-9.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/mortalidade , Infecção Hospitalar/mortalidade , Surtos de Doenças , Feminino , Pessoal de Saúde , Humanos , Controle de Infecções/métodos , Transmissão de Doença Infecciosa do Paciente para o Profissional , Masculino , Pessoa de Meia-Idade , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Septo Nasal/microbiologia , Estudos Prospectivos , Respiração Artificial , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Arábia Saudita/epidemiologia , Centros de Atenção Terciária
15.
Head Neck Pathol ; 10(4): 552-555, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27325235

RESUMO

Mycobacterium avium complex (MAC) is primarily a pulmonary pathogen that affects individuals who are immune deficient or immunocompromised. In this report, we describe a very rare case of MAC infection clinically presenting as a nasal polyp in a patient with type 2 diabetes mellitus. This case illustrates an atypical anatomic location for MAC, the anterior nasal septum in nasal cavity, as well as often overlooked cause of immune compromise, diabetes mellitus. We present the laboratory findings that lead to the diagnosis as well as a brief review of MAC infections.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Hospedeiro Imunocomprometido , Infecção por Mycobacterium avium-intracellulare/imunologia , Infecção por Mycobacterium avium-intracellulare/patologia , Septo Nasal/microbiologia , Idoso , Humanos , Masculino , Pólipos Nasais/microbiologia , Pólipos Nasais/patologia , Septo Nasal/patologia
16.
J Laryngol Otol ; 130(4): 352-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26857847

RESUMO

OBJECTIVE: To investigate the effects of different suture materials in the nasal cavity on encrustation and micro-organism colonisation. METHODS: Four different suture materials were used to suture the nasal septum. The effects of suture materials on intranasal encrustation were evaluated with anterior rhinoscopy. The sutures were removed and evaluated in terms of micro-organism colonisation on the 7th and 21st post-operative days. RESULTS: Monofilament sutures were found to cause less encrustation and micro-organism colonisation. There was increased late-stage encrustation if an absorbable monofilament suture remained in place for a long time. The removal of a non-absorbable monofilament suture in the early or late post-operative period made no difference in terms of micro-organism growth on the suture. CONCLUSION: The material and physical characteristics of sutures placed inside the nose may indirectly affect the healing process. It may be more appropriate to use different materials depending on the length of time the suture is to remain in place.


Assuntos
Cavidade Nasal/cirurgia , Septo Nasal/cirurgia , Procedimentos Cirúrgicos Nasais/métodos , Técnicas de Sutura , Suturas/efeitos adversos , Adolescente , Adulto , Humanos , Cavidade Nasal/microbiologia , Septo Nasal/microbiologia , Infecção da Ferida Cirúrgica/microbiologia , Suturas/microbiologia , Fatores de Tempo , Cicatrização , Adulto Jovem
17.
PLoS One ; 10(5): e0127098, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25970287

RESUMO

Human respiratory syncytial virus (HRSV) and Streptococcus pneumoniae are important causative agents of respiratory tract infections. Both pathogens are associated with seasonal disease outbreaks in the pediatric population, and can often be detected simultaneously in infants hospitalized with bronchiolitis or pneumonia. It has been described that respiratory virus infections may predispose for bacterial superinfections, resulting in severe disease. However, studies on the influence of bacterial colonization of the upper respiratory tract on the pathogenesis of subsequent respiratory virus infections are scarce. Here, we have investigated whether pneumococcal colonization enhances subsequent HRSV infection. We used a newly generated recombinant subgroup B HRSV strain that expresses enhanced green fluorescent protein and pneumococcal isolates obtained from healthy children in disease-relevant in vitro and in vivo model systems. Three pneumococcal strains specifically enhanced in vitro HRSV infection of primary well-differentiated normal human bronchial epithelial cells grown at air-liquid interface, whereas two other strains did not. Since previous studies reported that bacterial neuraminidase enhanced HRSV infection in vitro, we measured pneumococcal neuraminidase activity in these cultures but found no correlation with the observed infection enhancement in our model. Subsequently, a selection of pneumococcal strains was used to induce nasal colonization of cotton rats, the best available small animal model for HRSV. Intranasal HRSV infection three days later resulted in strain-specific enhancement of HRSV replication in vivo. One S. pneumoniae strain enhanced HRSV both in vitro and in vivo, and was also associated with enhanced syncytium formation in vivo. However, neither pneumococci nor HRSV were found to spread from the upper to the lower respiratory tract, and neither pathogen was transmitted to naive cage mates by direct contact. These results demonstrate that pneumococcal colonization can enhance subsequent HRSV infection, and provide tools for additional mechanistic and intervention studies.


Assuntos
Coinfecção/microbiologia , Infecções Pneumocócicas/virologia , Infecções por Vírus Respiratório Sincicial/microbiologia , Vírus Sinciciais Respiratórios/fisiologia , Streptococcus pneumoniae/fisiologia , Animais , Proteínas de Bactérias/fisiologia , Linhagem Celular , Feminino , Humanos , Interações Microbianas , Septo Nasal/microbiologia , Neuraminidase/fisiologia , Sigmodontinae
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