Performance of QuantiFERON-TB Gold Plus assays in paediatric tuberculosis: a multicentre PTBNET study.

RATIONALE: In 2016, a new interferon-gamma release assay (IGRA) was introduced, QuantiFERON-TB Gold Plus (QFT-Plus), claimed to have improved sensitivity in active tuberculosis (TB). OBJECTIVES: This study aimed to determine the performance of QFT-Plus, compared with previous generation IGRAs and the tuberculin skin test (TST), in children with TB in Europe. METHODS: Multicentre, ambispective cohort study within the Paediatric Tuberculosis Network European Trials Group (ptbnet), a dedicated paediatric TB research network comprising >300 members, capturing TB cases <18 years-of-age diagnosed between January 2009 and December 2019. MEASUREMENTS AND MAIN RESULTS: 1001 TB cases from 16 countries were included (mean age (IQR) 5.6 (2.4-12.1) years). QFT-Plus was performed in 358, QFT Gold in-Tube (QFT-GIT) in 600, T-SPOT.TB in 58 and TST in 636 cases. The overall test sensitivities were: QFT-Plus 83.8% (95% CI 80.2% to 87.8%), QFT-GIT 85.5% (95% CI 82.7% to 88.3%), T-SPOT.TB 77.6% (95% CI 66.9% to 88.3%) and TST (cut-off ≥10 mm) 83.3% (95% CI 83.3% to 86.2%). There was a trend for tests to have lower sensitivity in patients with miliary and/or central nervous system (CNS) TB (73.1%, 70.9%, 63.6% and 43.5%, respectively), and in immunocompromised patients (75.0%, 59.6%, 45.5% and 59.1%, respectively). CONCLUSIONS: The results indicate that the latest generation IGRA assay, QFT-Plus, does not perform better than previous generation IGRAs or the TST in children with TB disease. Overall, tests performed worse in CNS and miliary TB, and in immunocompromised children. None of the tests evaluated had sufficiently high sensitivity to be used as a rule-out test in children with suspected TB.

Performance of QuantiFERON-TB Gold Plus assays in children and adolescents at risk of tuberculosis: a cross-sectional multicentre study.

INTRODUCTION: The QuantiFERON-TB Gold Plus (QFT-Plus) assay, which features two antigen-stimulated tubes (TB1 and TB2) instead of a single tube used in previous-generation interferon-gamma release assays (IGRAs), was launched in 2016. Despite this, data regarding the assay's performance in the paediatric setting remain scarce. This study aimed to determine the performance of QFT-Plus in a large cohort of children and adolescents at risk of tuberculosis (TB) in a low-burden setting. METHODS: Cross-sectional, multicentre study at healthcare institutions participating in the Spanish Paediatric TB Research Network, including patients <18 years who had a QFT-Plus performed between September 2016 and June 2020. RESULTS: Of 1726 patients (52.8% male, median age: 8.4 years), 260 (15.1%) underwent testing during contact tracing, 288 (16.7%) on clinical/radiological suspicion of tuberculosis disease (TBD), 649 (37.6%) during new-entrant migrant screening and 529 (30.6%) prior to initiation of immunosuppressive treatment. Overall, the sensitivity of QFT-Plus for TBD (n=189) and for latent tuberculosis infection (LTBI, n=195) was 83.6% and 68.2%, respectively. The agreement between QFT-Plus TB1 and TB2 antigen tubes was excellent (98.9%, κ=0.961). Only five (2.5%) patients with TBD had discordance between TB1 and TB2 results (TB1+/TB2-, n=2; TB1-/TB2+, n=3). Indeterminate assay results (n=54, 3.1%) were associated with young age, lymphopenia and elevated C reactive protein concentrations. CONCLUSIONS: Our non-comparative study indicates that QFT-Plus does not have greater sensitivity than previous-generation IGRAs in children in both TBD and LTBI. In TBD, the addition of the second antigen tube, TB2, does not enhance the assay's performance substantially.

Interferon-Gamma Release Assays Differentiate between Mycobacterium avium Complex and Tuberculous Lymphadenitis in Children.

OBJECTIVES: To assess the performance of interferon-gamma release assays (IGRAs) in the differential diagnosis between Mycobacterium avium complex (MAC) and tuberculosis (TB) in children affected with subacute/chronic submandibular/cervical lymphadenitis. STUDY DESIGN: Multicenter observational study comparing children with microbiologically confirmed MAC lymphadenitis from the European NontuberculouS MycoBacterial Lymphadenitis in childrEn study with children with TB lymphadenitis from the Spanish Network for the Study of Pediatric TB database. RESULTS: Overall, 78 patients with MAC and 34 with TB lymphadenitis were included. Among MAC cases, 44 out of 74 (59.5%) had positive tuberculin skin test (TST) results at the 5-mm cut-off, compared with 32 out of 33 (97%) TB cases (P < .001); at the 10-mm cut-off TST results were positive in 23 out of 74 (31.1%) vs 26 out of 31 (83.9%), respectively (P < .001). IGRA results were positive in only 1 out of 32 (3.1%) patients with MAC who had undergone IGRA testing, compared with 21 out of 23 (91.3%) TB cases (P < .001). Agreement between TST and IGRA results was poor in MAC (23.3%; κ = 0.017), but good in TB cases (95.6%; κ = 0.646). IGRAs had a specificity of 96.9% (95% CI 84.3%-99.8%), positive predictive value of 95.4% (95% CI 78.2%-99.8%), and negative predictive value of 93.9% (95% CI 80.4%-98.9%) for TB lymphadenitis. CONCLUSIONS: In contrast to TST, IGRAs have high specificity, negative predictive value, and positive predictive value for TB lymphadenitis in children with subacute/chronic lymphadenopathy, and consequently can help to discriminate between TB and MAC disease. Therefore, IGRAs are useful tools in the diagnostic work-up of children with lymphadenopathy, particularly when culture and polymerase chain reaction results are negative.

The Value of the Second QuantiFERON-TB Gold-Plus Antigen Tube at Diagnosis and at Treatment Completion in Spanish Children With Tuberculosis.

We studied 295 children (tuberculosis disease, n = 159; latent tuberculosis infection, n = 136) with positive QuantiFERON-TB Gold-Plus assay results. No significant differences between first and second antigen tube interferon-gamma responses were detected, irrespective of patient and disease characteristics at diagnosis. Of patients with a repeat assay after treatment completion (n = 65), only 16.9% converted to negative results.

Transient Viral Rebound in Children with Perinatally Acquired HIV-1 Induces a Unique Soluble Immunometabolic Signature Associated with Decreased CD4/CD8 Ratio.

BACKGROUND: To determine by multi-omic analysis changes in metabolites, lipids, and proteins as a consequence of transient viral rebound (tVR) in children with perinatally acquired HIV-1 (PHIV). METHODS: Plasma samples from children with PHIV and with tVR (first episode of transient RNA-HIV viral load >20 copies/ml followed by suppression) on the time-point immediately before (pre-tVR) and after (post-tVR) the tVR were assessed. Multi-omic analyses were performed using nLC-Orbitrap, GC-qTOF-MS, and LC-qTOF-MS. RESULTS: Comparing pre- and post-tVR time-points, HIV-1 children with tVR (n = 5) showed a trend to a decrease in ratio CD4/CD8 (p = 0.08) but no significant differences were observed in plasma metabolites, lipids, or proteins. Post-tVR condition was compared with a reference group of children with PHIV with persistent viral control (n = 9), paired by sex, age, and time under antiretroviral treatment. A total of 10 proteins, 8 metabolites, and 2 lipids showed significant differences (p < 0.05): serotransferrin, clusterin, kininogen-1, succinic acid, threonine, 2-hydroxyisovaleric acid, methionine, 2-hydroxyglutaric, triacylglyceride 50:0 (TG50:0), and diacylglyceride 34:1 (DG34:1) were upregulated while alpha-2-macroglobulin, apolipoprotein A-II, carboxylic ester hydrolase, apolipoprotein D, coagulation factor IX, peptidase inhibitor 16, SAA2-SAA4 readthrough, oleic acid, palmitoleic acid, and D-sucrose downregulated on post-tVR time-point compared to the reference group. Ratio CD4/CD8 correlated with apolipoprotein A-II, DG34:1, and methionine (p = 0.004; ρ = 0.71, p = 0.016; ρ = -0.63; and p = 0.032; ρ = -0.57, respectively). Nadir CD4+ correlated inversely with kininogen-1 (p = 0.022; ρ = -0.60) and positively with D-sucrose (p = 0.001; ρ = 0.77). CONCLUSIONS: tVR followed by suppression implies changes in soluble proteins, lipids, and metabolites that correlate with immunological parameters, mainly ratio CD4/CD8, that decreased after tVR. These distinct soluble biomarkers could be considered potential biomarkers of immune progression.

Prevalence and Clinical Characteristics of Children With Nonsevere Tuberculosis in Spain.

BACKGROUND: To assess the prevalence and characteristics of nonsevere TB among children in Spain. It has been recently demonstrated that these children can be treated with a 4-month regimen instead of the classical 6-month treatment regimen, with the same effectivity and outcomes, decreasing toxicity and improving adherence. METHODS: We conducted a retrospective cohort study in a cohort of children ≤16 years of age with TB. Nonsevere TB cases included smear-negative children with respiratory TB confined to 1 lobe, with no significant airway obstruction, no complex pleural effusion, no cavities and no signs of miliary disease, or with peripheral lymph-node disease. The remaining children were considered to have severe TB. We estimated the prevalence of nonsevere TB and compared the clinical characteristics and outcomes between children with nonsevere and severe TB. RESULTS: A total of 780 patients were included [46.9% males, median age 5.5 years (IQR: 2.6-11.1)], 477 (61.1%) of whom had nonsevere TB. Nonsevere TB was less frequent in children <1 year (33% vs 67%; P < 0.001), and >14 years of age (35% vs 65%; P = 0.002), mostly diagnosed in contact tracing studies (60.4% vs 29.2%; P < 0.001) and more frequently asymptomatic (38.3% vs 17.7%; P < 0.001). TB confirmation in nonsevere disease was less frequent by culture (27.0% vs 57.1%; P < 0.001) and by molecular tests (18.2% vs 48.8%; P < 0.001). Sequelae were less frequent in children with nonsevere disease (1.7 vs 5.4%; P < 0.001). No child with nonsevere disease died. CONCLUSIONS: Two-thirds of children had nonsevere TB, mostly with benign clinical presentation and negative microbiologic results. In low-burden countries, most children with TB might benefit from short-course regimens.

QuantiFERON-TB Gold Plus Assay Specificity in Children and Adolescents With Suspected Tuberculosis-A Multicenter Cross-sectional Study in Spain.

In this cross-sectional study of 284 children and adolescents with clinically or radiologically suspected tuberculosis in a low-endemic country, the QuantiFERON-TB Gold Plus assay specificity, sensitivity, positive predictive value and negative predictive value were 91.5%, 87.3%, 86.4%, and 91.2%, respectively. The specificity was higher than that observed in tuberculin skin tests performed simultaneously, but similar to previous-generation interferon-gamma release assays.

[Acute mastoiditis with intracranial complication in a pediatric patient]. / Mastoiditis aguda con complicación intracraneal. Reporte de un caso pediátrico.

Acute mastoiditis is an infection that affects the mastoid air-cell system, usually due to the progression of an acute otitis media. The bacteria most frequently isolated in acute mastoiditis are Streptococcus pneumoniae, Streptococcus pyogenes and Staphylococcus aureus. The mastoid infection can extend affecting contiguous structures and producing intra or extracranial complications. The most frequent ones are intracranial complications, including meningitis, temporal lobe or cerebellar abscess, epidural or subdural abscess and venous sinus thrombosis. We present the case of a 4-year-old girl who developed two intracranial complications (intracranial epidural abscess and transverse and sigmoid sinus thrombosis) initiated in an acute mastoiditis produced by Streptococcus pyogenes.

La mastoiditis aguda es una infección de las celdillas mastoideas, generalmente, secundaria a la progresión de una otitis media aguda. Las bacterias aisladas con más frecuencia en las mastoiditis son Streptococcus pneumoniae, Streptococcus pyogenes y Staphylococcus aureus. La infección mastoidea puede extenderse por contigüidad, afectar a estructuras vecinas y dar lugar a complicaciones intra- o extracraneales. Las más frecuentes son las intracraneales, entre las que se incluyen la meningitis, el absceso cerebeloso o del lóbulo temporal, el absceso epi- o subdural y la trombosis de senos venosos. Se presenta el caso de una niña de 4 años que desarrolló dos complicaciones intracraneales (absceso epidural y trombosis de senos venosos transverso y sigmoideo) a partir de una mastoiditis aguda producida por Streptococus pyogenes.

Epidemiological and clinical features of Kawasaki disease in Spain over 5 years and risk factors for aneurysm development. (2011-2016): KAWA-RACE study group.

BACKGROUND: Kawasaki disease (KD) is an acute self-limited systemic vasculitis of unknown etiology affecting mainly children less than 5 years of age. Risk factors for cardiac involvement and resistance to treatment are insufficiently studied in non-Japanese children. OBJECTIVE: This study aimed to investigate the epidemiology, clinical features and risk factors for resistance to treatment and coronary artery lesions (CAL) in KD in Spain. METHODS: Retrospective study (May 2011-June 2016) of all patients less than 16 years of age diagnosed with KD included in KAWA-RACE network (84 Spanish hospitals). RESULTS: A total of 625 cases were analyzed, 63% were males, 79% under 5 year-olds and 16.8% younger than 12 months. On echocardiographic examination CAL were the most frequent findings (23%) being ectasia the most common (12%). Coronary aneurysms were diagnosed in 9.6%, reaching 20% in infants under 12 months (p<0.001). A total of 97% of the patients received intravenous immunoglobulin (IVIG) with a median number of days from fever onset to IVIG administration of 7.2. A second dose was given to 15.7% and steroids to 14.5% patients. Only 1.4% patients received infliximab. No deaths were reported. A multivariate analysis identified anemia, hypoalbuminemia, hyponatremia, higher creatinine and procalcitonin as independent risk factors for treatment failure and length under 103 cm, hemoglobin < 10.2 mg/dL, platelets > 900,000 cells/mm3, maximum temperature < 39.5°C, total duration of fever > 10 days and fever before treatment ≥ 8 days as independent risk factors for developing coronary aneurysms. CONCLUSIONS: In our population, children under 12 months develop coronary aneurysms more frequently and children with KD with anemia and leukocytosis have high risk of cardiac involvement. Adding steroids early should be considered in those patients, especially if the treatment is not started before 8 days of fever. A score applicable to non-Japanese children able to predict the risk of aneurysm development and IVIG resistance is necessary.

[Encephalopathy due to human herpesvirus 6 infection as exanthema subitum complication]. / Encefalopatía por virus herpes 6 como complicación de exantema súbito.

The main clinical manifestation of human herpesvirus 6 is exanthema subitum (also known as roseola infantum) and febrile syndrome. Central nervous system manifestations are not unusual in herpesvirus 6 infection, and even though the pathophysiology is not clear, they need to be early diagnosed and treated in order to avoid potentially serious damage. We present the case of an immunocompetent 2-year-old girl with encephalitis as a complication of herpesvirus 6 infection. We want to emphasize the significance of an early diagnosis and treatment in order to prevent further complications due to the central nervous system extension.

La principal manifestación clínica del herpesvirus 6 es el exantema súbito (también conocido como roséola o sexta enfermedad) y el síndrome febril. Las manifestaciones en el sistema nervioso central no son infrecuentes en la infección por herpesvirus 6, y su fisiopatología no está esclarecida, pero precisan diagnóstico y tratamiento temprano para evitar secuelas potencialmente graves. Se presenta el caso de una niña inmunocompetente de 2 años con cuadro de encefalitis como complicación de infección por herpesvirus 6. Se destaca la importancia del diagnóstico oportuno a fin de instaurar un adecuado tratamiento y seguimiento para evitar complicaciones secundarias a la afectación del sistema nervioso central.

Disseminated Tuberculosis Resulting From Reinfection in a Pediatric Patient Sequentially Treated With Etanercept and Adalimumab.

Treatment with tumor necrosis factor α inhibitors is a risk factor for tuberculosis (TB). Despite previous treatment with isoniazid for latent TB, a 9-year-old girl with juvenile idiopathic arthritis developed disseminated TB after changing therapy with etanercept to adalimumab and after new contact with a smear-positive relative. Genotyping strain matches and susceptibility to isoniazid make reinfection more likely than reactivation in our patient.

[Lymphadenitis due to non-tuberculous mycobacteria: Experience over 15 years]. / Linfadenitis por micobacterias no tuberculosas: experiencia de 15 años.

OBJECTIVE: To study the epidemiology, clinical features, diagnosis, therapeutic management, and outcome of non-tuberculous mycobacterial lymphadenitis in a paediatric population of Aragón (Spain). MATERIAL AND METHODS: A retrospective study was conducted on patients under 15 years-old diagnosed with non-tuberculous mycobacterial lymphadenitis between the years 2000 and 2015. INCLUSION CRITERIA: patients with lymphadenitis and positive culture. Quantitative values are shown as mean, rank, and standard deviation, and qualitative data as frequencies. RESULTS: Twenty-seven cases were registered, with a mean age of presentation of 39.9 months (range 10 months-8 years). The mean time between the symptoms onset and first consultation was 1.7±1.1 months. The most frequent location was sub-maxilar in 17/27 cases (63%), on the right side in 59.3%, and size 2.96±1.26cm. Fistulae were observed in 16/27 cases. Tuberculin test was greater than 10mm in 7/24 (29.1%). Microbiological cultures were positive for Mycobacterium avium in 14/27 (51.9%), Mycobacterium intracellulare 3/27 (11.1%), and Mycobacterium lentiflavum 3/27 (11.1%). Combined treatment of antibiotics and surgery was given in 16/27 cases (59.8%), medical treatment only in7/27 (25.9%), and surgical exeresis alone in 4/27 (14.8%). Two patients required a new surgery, and one showed severe neutropenia secondary to rifabutin. Only one case (3.7%) suffered from temporary facial palsy as sequel. CONCLUSIONS: The most frequent treatment was the combination of antibiotics and surgery. Delay in diagnosis seemed to be responsible for the limited number of exeresis as first option, only one for every seven patients.

[Sepsis due to Pseudomona as a debut of a primary immunodeficiency in a child]. / Sepsis por Pseudomona como forma de debut de inmunodeficiencia primaria en un niño.

X-linked agammaglobulinemia is a primary humoral immunodeficiency. It is a recessive X-linked disorder characterized by low or absent circulating mature B cells, hypo/agammaglobulinemia and no humoral response to immunizations due to mutations along chromosome X. It is characterized by severe, recurrent and difficult treatment infections. It is diagnosed in the first 6 months of life in children; the only sign of alarm is the absent or decreased size of tonsils and lymph nodes, but it is not always present. The main cornerstones of treatment are immunoglobulin replacement therapy to maintain serum levels above 500-700 mg/dl and infection control; this allows these patients to do their day-to-day activities. We report a 2 year old boy with X-linked agammaglobulinemia, with no history of interest, who presented with P. aeruginosa sepsis. He had an excellent clinical improvement without further important infections after intravenous immunoglobulin replacement therapy.

La agammaglobulinemia ligada al X es una inmunodeficiencia humoral primaria, recesiva y ligada al cromosoma X, en la que existe una disminución marcada de linfocitos B maduros, hipo-/agammaglobulinemia y escasa respuesta humoral a las inmunizaciones, debido a mutaciones en el brazo largo del cromosoma X. Se caracteriza por infecciones graves, recurrentes y difíciles de tratar, que ocurren, generalmente, a partir de los 6 meses. El único signo de alarma, no siempre presente, es la ausencia o disminución del tamaño de las amígdalas y los ganglios linfáticos. El tratamiento de elección es el sustitutivo con inmunoglobulina G intravenosa para mantener niveles séricos por encima de 500-700 mg/dl y el control de las infecciones, lo que permite que estos pacientes hagan sus tareas habituales. Se presenta un niño de 2 años sin antecedentes personales ni familiares relevantes diagnosticado con agammaglobulinemia ligada al X tras una sepsis por P. aeruginosa. Tuvo una evolución clínica adecuada sin nuevos episodios infecciosos importantes tras el inicio del tratamiento sustitutivo con inmunoglobulina G intravenosa mensual.

[Mycobacterium lentiflavum lymphadenitis: two case reports]. / Linfadenitis por Mycobacterium lentiflavum: reporte de dos casos.

Lymphadenitis is the most common clinical feature in nontuberculous mycobacterium infection in immunocompetent children. We present two case reports of M. lentiflavum lymphadenitis diagnosed in a tertiary hospital in the last 10 years. Routine tests were performed after persistent adenopathy, and a sample for culture was obtained, being positive for this microorganism. Both patients received oral antibiotics during several weeks. Case 1 needed complete excision after five months of treatment, whilst Case 2 was cured by medical therapy. M. lentiflavum is considered, among the newly described nontuberculous mycobacterial species, an emergent pathogen in our environment. It has its own microbiological and clinical characteristics, different from the rest of nontuberculous mycobacteria. Case reports are limited in the literature since the infection was described for the first time in 1997.

La linfadenitis es la manifestación clínica más frecuente de la infección por micobacterias no tuberculosas en niños inmunocompetentes. Se presentan dos casos de linfadenitis por M. lentiflavum diagnosticados en un hospital de tercer nivel en los últimos 10 años. Se realizaron pruebas complementarias de rutina ante adenopatía persistente y se obtuvo una muestra mediante drenaje para el cultivo, que resultó positivo para este germen. Ambos pacientes recibieron tratamiento antibiótico oral durante varias semanas. El caso 1 precisó exéresis completa al quinto mes de evolución, mientras que el caso 2 presentó resolución completa de la lesión a los 4 meses. M. lentiflavum es considerado, de entre las nuevas especies de micobacterias no tuberculosas recientemente descritas, un germen emergente en nuestro medio. Posee unas características microbiológicas y clínicas especiales, diferentes del resto de las micobacterias no tuberculosas. Son pocos los casos publicados hasta la fecha desde que se describió por primera vez la infección en 1997.

Mastoiditis aguda con complicación intracraneal. Reporte de un caso pediátrico / Acute mastoiditis with intracranial complication in a pediatric patient

La mastoiditis aguda es una infección de las celdillas mastoideas, generalmente, secundaria a la progresión de una otitis media aguda. Las bacterias aisladas con más frecuencia en las mastoiditis son Streptococcus pneumoniae, Streptococcus pyogenes y Staphylococcus aureus. La infección mastoidea puede extenderse por contigüidad, afectar a estructuras vecinas y dar lugar a complicaciones intra- o extracraneales. Las más frecuentes son las intracraneales, entre las que se incluyen la meningitis, el absceso cerebeloso o del lóbulo temporal, el absceso epi- o subdural y la trombosis de senos venosos.Se presenta el caso de una niña de 4 años que desarrolló dos complicaciones intracraneales (absceso epidural y trombosis de senos venosos transverso y sigmoideo) a partir de una mastoiditis aguda producida por Streptococus pyogenes

Acute mastoiditis is an infection that affects the mastoid air-cell system, usually due to the progression of an acute otitis media. The bacteria most frequently isolated in acute mastoiditis are Streptococcus pneumoniae, Streptococcus pyogenes and Staphylococcus aureus. The mastoid infection can extend affecting contiguous structures and producing intra or extracranial complications. The most frequent ones are intracranial complications, including meningitis, temporal lobe or cerebellar abscess, epidural or subdural abscess and venous sinus thrombosis.We present the case of a 4-year-old girl who developed two intracranial complications (intracranial epidural abscess and transverse and sigmoid sinus thrombosis) initiated in an acute mastoiditis produced by Streptococcus pyogenes.

Encefalopatía por virus herpes 6 como complicación de exantema súbito / Encephalopathy due to human herpesvirus 6 infection as exanthema subitum complication

La principal manifestación clínica del herpesvirus 6 es el exantema súbito (también conocido como roséola o sexta enfermedad) y el síndrome febril. Las manifestaciones en el sistema nervioso central no son infrecuentes en la infección por herpesvirus 6, y su fisiopatología no está esclarecida, pero precisan diagnóstico y tratamiento temprano para evitar secuelas potencialmente graves. Se presenta el caso de una niña inmunocompetente de 2 años con cuadro de encefalitis como complicación de infección por herpesvirus 6. Se destaca la importancia del diagnóstico oportuno a fin de instaurar un adecuado tratamiento y seguimiento para evitar complicaciones secundarias a la afectación del sistema nervioso central.

The main clinical manifestation of human herpesvirus 6 is exanthema subitum (also known as roseola infantum) and febrile syndrome. Central nervous system manifestations are not unusual in herpesvirus 6 infection, and even though the pathophysiology is not clear, they need to be early diagnosed and treated in order to avoid potentially serious damage. We present the case of an immunocompetent 2-year-old girl with encephalitis as a complication of herpesvirus 6 infection. We want to emphasize the significance of an early diagnosis and treatment in order to prevent further complications due to the central nervous system extension.

Linfadenitis por Mycobacterium lentiflavum: Reporte de dos casos / Mycobacterium lentiflavum lymphadenitis: Two case reports

La linfadenitis es la manifestación clínica más frecuente de la infección por micobacterias no tuberculosas en niños inmunocompetentes. Se presentan dos casos de linfadenitis por M. lentiflavum diagnosticados en un hospital de tercer nivel en los últimos 10 años. Se realizaron pruebas complementarias de rutina ante adenopatía persistente y se obtuvo una muestra mediante drenaje para el cultivo, que resultó positivo para este germen. Ambos pacientes recibieron tratamiento antibiótico oral durante varias semanas. El caso 1 precisó exéresis completa al quinto mes de evolución, mientras que el caso 2 presentó resolución completa de la lesión a los 4 meses. M. lentiflavum es considerado, de entre las nuevas especies de micobacterias no tuberculosas recientemente descritas, un germen emergente en nuestro medio. Posee unas características microbiológicas y clínicas especiales, diferentes del resto de las micobacterias no tuberculosas. Son pocos los casos publicados hasta la fecha desde que se describió por primera vez la infección en 1997.

Lymphadenitis is the most common clinical feature in nontuberculous mycobacterium infection in immunocompetent children. We present two case reports of M. lentiflavum lymphadenitis diagnosed in a tertiary hospital in the last 10 years. Routine tests were performed after persistent adenopathy, and a sample for culture was obtained, being positive for this microorganism. Both patients received oral antibiotics during several weeks. Case 1 needed complete excision after five months of treatment, whilst Case 2 was cured by medical therapy. M. lentiflavum is considered, among the newly described nontuberculous mycobacterial species, an emergent pathogen in our environment. It has its own microbiological and clinical characteristics, different from the rest of nontuberculous mycobacteria. Case reports are limited in the literature since the infection was described for the first time in 1997.