Carlos Garcés

CC8 MRSA Strains Harboring SCCmec Type IVc are Predominant in Colombian Hospitals

Background Recent reports highlight the incursion of community-associated MRSA within healthcare settings. However, knowledge of this phenomenon remains limited in Latin America. The aim of this study was to evaluate the molecular epidemiology of MRSA in three tertiary-care hospitals in Medellín, Colombia. Methods An observational cross-sectional study was conducted from 2008–2010. MRSA infections were classified as either community-associated (CA-MRSA) or healthcare-associated (HA-MRSA), with HA-MRSA further classified as hospital-onset (HAHO-MRSA) or community-onset (HACO-MRSA) according to standard epidemiological definitions established by the U.S. Centers for Disease Control and Prevention (CDC). Genotypic analysis included SCCmec typing, spa typing, PFGE and MLST. Results Out of 538 total MRSA isolates, 68 (12.6%) were defined as CA-MRSA, 243 (45.2%) as HACO-MRSA and 227 (42.2%) as HAHO-MRSA. The majority harbored SCCmec type IVc (306, 58.7%), followed by SCCmec type I (174, 33.4%). The prevalence of type IVc among CA-, HACO- and HAHO-MRSA isolates was 92.4%, 65.1% and 43.6%, respectively. From 2008 to 2010, the prevalence of type IVc-bearing strains increased significantly, from 50.0% to 68.2% (p = 0.004). Strains harboring SCCmec IVc were mainly associated with spa types t1610, t008 and t024 (MLST clonal complex 8), while PFGE confirmed that the t008 and t1610 strains were closely related to the USA300-0114 CA-MRSA clone. Notably, strains belonging to these three spa types exhibited high levels of tetracycline resistance (45.9%). Conclusion CC8 MRSA strains harboring SCCmec type IVc are becoming predominant in Medellín hospitals, displacing previously reported CC5 HA-MRSA clones. Based on shared characteristics including SCCmec IVc, absence of the ACME element and tetracycline resistance, the USA300-related isolates in this study are most likely related to USA300-LV, the recently-described ‘Latin American variant’ of USA300.

A comparison of methicillin-resistant and methicillin-susceptible Staphylococcus aureus reveals no clinical and epidemiological but molecular differences

Most studies on Staphylococcus aureus have focused on the molecular epidemiology of methicillin-resistant S. aureus (MRSA) infections. In contrast, little information is available regarding the molecular epidemiology of currently circulating methicillin-susceptible S. aureus (MSSA) isolates in hospital settings, an epoch when the epidemiology of S. aureus has undergone significant changes. We conducted a cross-sectional study to compare the clinical, epidemiological, and genetic characteristics of MSSA and MRSA isolates at 3 tertiary-care hospitals in Medellín, Colombia, from February 2008 to June 2010. The infections were classified according to the Centers for Disease Control and Prevention (CDC) definitions. Genotypic analysis included spa typing, multilocus sequence typing (MLST) and staphylococcal cassette chromosome (mec) (SCCmec) typing. A total of 810 patients was enrolled. One hundred infections (12.3%) were classified as community-associated (31 CA-MSSA, 69 CA-MRSA), 379 (46.8%) as healthcare-associated community-onset (136 HACO-MSSA, 243 HACO-MRSA), and 331 (40.9%) as healthcare-associated hospital-onset (104 HAHO-MSSA, 227 HAHO-MRSA). Genotype analyses showed a higher diversity and a more varied spa type repertoire in MSSA than in MRSA strains. Most of the clinical-epidemiological characteristics and risk factors evaluated did not allow for discriminating MRSA- from MSSA-infected patients. The lack of equivalence among the genetic backgrounds of the major MSSA and MRSA clones would suggest that the MRSA clones are imported instead of arising from successful MSSA clones. This study emphasizes the importance of local surveillance to create public awareness on the changing S. aureus epidemiology.

Clinical Characteristics of Carbapenem-resistant Klebsiella pneumoniae Infections in Ill and Colonized Children in Colombia.

Background: Multidrug-resistant Gram-negative infections represent a growing problem and a serious global threat. Data in children are scarce. Klebsiella pneumoniae carbapenemases (KPC) are the most common mechanism of resistance this organism has developed. We report the clinical characteristics and outcomes from a cohort of children infected or colonized with carbapenem-resistant K. pneumoniae (CRKp) at a tertiary care center in Medellín, Colombia. Methods: We performed a retrospective chart review of all pediatric cases from whom CRKp isolates were obtained from 2008 to 2013. Clinical characteristics and outcomes were recorded. Results: A total of 34 infected children (median age, 22.8 months) with 43 episodes and 55 colonized patients (median age, 33 months) were identified. All patients had at least 1 risk factor previously related with multidrug-resistant Gram-negative infections (premorbid conditions, previous exposure to antibiotics, prolonged length of stay and use of indwelling devices). Urinary tract infections, abdominal infections and bacteremia were the most common clinical presentations. Overall mortality was 38%, and it was lower when a meropenem-containing regimen was used. Colistin was the most used antibiotic either alone or in combination and was associated with 8.8% of nephrotoxicity. Conclusion: CRKp infections have high mortality in children and usually occur in children with comorbidities, prolonged hospital stay and prior antibiotic exposure. Combined therapy with meropenem-containing regimens seems to be the best option in severely ill children.

Experiencia con el uso compasivo de tigeciclina en pacientes pediátricos infectados por Klebsiella pneumoniae productora de carbapenemasas

INTRODUCTION Infections produced by multidrug-resistant pathogens represent a therapeutic challenge because of the few therapeutic options available. Tigecycline is a relatively new antibiotic, with a wide spectrum of activity including some of these resistant bacteria. In adults is prescribed for the treatment of some infections caused by carbapenem resistant K. pneumoniae, however it has not been approved in children because of potential adverse effects in the dental enamel. MATERIALS AND METHODS Case series study. Medical records were reviewed in all children from 0 to 14 years of age that received tigecycline between January of 2008 and March of 2010. RESULTS 9 patients received Tigecycline mainly for treatment of peritonitis, bacteremia, pneumonia and sepsis caused by carbapenem resistant K. pneumoniae. A dose of 1 mg/kg q 12 hours was administered to all patients. No adverse events were reported and a total of 6 patients had complete resolution of the infection. CONCLUSIONS Tigecycline could be considered a therapeutic option for treating infections produced by multidrug-resistant pathogens in children. The use in children is still compassionate and in this series of cases Tigecycline was well tolerated and safe.Introduction: Infections produced by multidrug-resistant pathogens represent a therapeutic challenge because of the few therapeutic options available. Tigecycline is a relatively new antibiotic, with a wide spectrum of activity including some of these resistant bacteria. In adults is prescribed for the treatment of some infections caused by carbapenem resistant K. pneumoniae, however it has not been approved in children because of potential adverse effects in the dental enamel. Materials and Methods: Case series study. Medical records were reviewed in all children from 0 to 14 years of age that received tigecycline between January of 2008 and March of 2010. Results: 9 patients received Tigecycline mainly for treatment of peritonitis, bacteremia, pneumonia and sepsis caused by carbapenem resistant K. pneumoniae. A dose of 1 mg/kg q 12 hours was administered to all patients. No adverse events were reported and a total of 6 patients had complete resolution of the infection. Conclusions: Tigecycline could be considered a therapeutic option for treating infections produced by multidrug-resistant pathogens in children. The use in children is still compassionate and in this serie of cases Tigecycline was well tolerated and safe.

Fungemia due to Kodamaea ohmeri in a young infant and review of the literature.

Fungal infections have become an important cause of morbidity and mortality in hospitalized children due to many complicating and underlying conditions. We present the case of a newborn infant with fungemia due to Kodamaea ohmeri who had a good outcome of the infection after using the combination of antifungal treatment and central venous catheter removal.

Evolución clínica y de laboratorio de episodios de neutropenia febril en niños con cáncer, en un hospital de Colombia, período 2007-2009

INTRODUCTION Neutropenia is one of the most common complications in children with cancer, and its the most important parameter to determine infection risk. In neutropenic patients the signs and symptoms could be scarce and in occasions fever could be the only symptom. For these reasons all patients with febrile neutropenia (FN) should be considered as if they had a possibly severe disease. AIM To describe the clinical characteristics and laboratory parameters observed in cancer patients with FN attended at our hospital to perform a more rational management of this complication in the future. PATIENTS AND METHODS The clinical files accumulated during 36 months, belonging to patients aged 0 to 15 years that were hospitalized because of cancer and FN were reviewed. RESULTS In this series the source of fever was found in 48.6% of 105 NF episodes, and bacteria were isolated from blood or urine culture in 38%. The most frequent bacterial species recovered were methicillin susceptible S. aureus (20.8%) and ESBL negative E. coli (20.8%). Piperacillin/tazobactam was the most used first line antibiotic prescribed (87.6%) and meropenem was the second choice (18%). Granulocyte colony stimulating factor was used in 61.9% of the cases and episodes mortality rate was 6.7%. CONCLUSION Clinical characteristics and bacteriological findings in our institution do not differ significantly from what has been described for pediatric cancer patients in other series.

Cat scratch disease in Medellín, Colombia

Cat scratch disease (CSD) is the most common zoonosis transmitted by household animals. There is limited data on the epidemiology and clinical presentation of this disease in Colombia. The typical presentation includes subacute or chronic lymph node infection following inoculation of Bartonella henselae bacilli through a cat scratch. Cats have a B. henselae seroprevalence as high as 90%. Here, we report the case of a preschool boy from a rural area of Antioquia, Colombia, who presented with chronic lymphadenopathy in the right axilla. Other important infectious etiologies were ruled out, and confirmation was made with the Warthin Starry stain of a lymph node biopsy. We also discuss the most important aspects of the diagnosis, treatment and prevention of the disease.

Tuberculosis cerebral sin meningitis en un niño inmunocompetente

Cerebral tuberculosis TB (tuberculomas) without meningitis is an uncommon disease with a high morbidity and mortality. We report on a case that illustrates the complexity of this clinical presentation. An 11 month old, previously healthy male infant was brought to the clinic due to fever present during the last 1.5 months, associated with loss of neurodevelopmental goals and signs of endocranial hypertension. CT scan of the skull revealed dilatation of the ventricular system with transependimary edema; MRI showed multiple intra- and extra-axial micronodular images and hydrocephalus. Studies of CSF (cyto-chemical analysis, staining, culture for aerobes, fungi, mycobacteria, and molecular tests for TB were negative). Empirical management for subacute meningoencephalitis was prescribed complemented with tetraconjugated treatment for TB and steroids. As there was no microbiological isolation, biopsy of a cerebellar lesion was performed, which revealed chronic necrotizing granulomatous inflammation and acid-alcohol resistant bacilli. The diagnosis of cerebral TB without meningeal involvement was confirmed. The objective of the present report is to emphasize the importance of considering this presentation of TB in children, to remark the need of exhaustive search for the etiologic agent by obtaining samples of the different fluids and tissues even if it implies recurring to invasive methods.

Early-Onset Invasive Infection Due to Corynespora cassiicola Associated with Compound Heterozygous CARD9 Mutations in a Colombian Patient

PurposeCARD9 deficiency is an inborn error of immunity that predisposes otherwise healthy humans to mucocutaneous and invasive fungal infections, mostly caused by Candida, but also by dermatophytes, Aspergillus, and other fungi. Phaeohyphomycosis are an emerging group of fungal infections caused by dematiaceous fungi (phaeohyphomycetes) and are being increasingly identified in patients with CARD9 deficiency. The Corynespora genus belongs to phaeohyphomycetes and only one adult patient with CARD9 deficiency has been reported to suffer from invasive disease caused by C. cassiicola. We identified a Colombian child with an early-onset, deep, and destructive mucocutaneous infection due to C. cassiicola and we searched for mutations in CARD9.MethodsWe reviewed the medical records and immunological findings in the patient. Microbiologic tests and biopsies were performed. Whole-exome sequencing (WES) was made and Sanger sequencing was used to confirm the CARD9 mutations in the patient and her family. Finally, CARD9 protein expression was evaluated in peripheral blood mononuclear cells (PBMC) by western blotting.ResultsThe patient was affected by a large, indurated, foul-smelling, and verrucous ulcerated lesion on the left side of the face with extensive necrosis and crusting, due to a C. cassiicola infectious disease. WES led to the identification of compound heterozygous mutations in the patient consisting of the previously reported p.Q289* nonsense (c.865C > T, exon 6) mutation, and a novel deletion (c.23_29del; p.Asp8Alafs10*) leading to a frameshift and a premature stop codon in exon 2. CARD9 protein expression was absent in peripheral blood mononuclear cells from the patient.ConclusionWe describe here compound heterozygous loss-of-expression mutations in CARD9 leading to severe deep and destructive mucocutaneous phaeohyphomycosis due to C. cassiicola in a Colombian child.

Uso actual de los antifúngicos triazoles en niños

Resumen Las infecciones fungicas invasoras en ninos inmunocomprometidos han aumentado en las ultimas decadas debido al incremento de la poblacion en riesgo, asi como a los avances de la medicina. La AMB y los azoles, especialmente los de primera generacion, han sido los antifungicos mas utilizados en esta poblacion. En los ultimos anos, se han descubierto nuevos azoles. Sin embargo, gran parte de la informacion acerca de la dosificacion y seguridad de estos medicamentos en pediatria ha sido extrapolada de los adultos, ya que los estudios de farmacocinetica y farmacodinamica en