Fungal infections in pediatric neurosurgery.

INTRODUCTION: Invasive mycosis of the central nervous system represent a diverse group of diseases that have gradually emerged as not only opportunistic infections in patients with immune susceptibility due to congenital and acquired deficiency, immunomodulation, solid organ and stem cell transplantation, hematological malignancies, and chronic steroid use but also in selected risk populations such as low weight preterm infants, patients with shunted hydrocephalus and external ventricular drainages, skull base surgery, and head injury. OBJECTIVES: The purpose of this review is to familiarize the pediatric neurosurgeon with the most common mycosis and their clinical scenarios which can be encountered in the clinical practice, with special emphasis on clinical, radiological, and laboratory diagnosis beyond classical microorganism cultures as well as options in medical and surgical treatment given the high incidence of morbidity and mortality associated with these challenging entities. METHODS: We conducted an online database review (Ovid, PubMed) gathering relevant English language literature published in the last 20 years with special emphasis on recent breakthroughs in the diagnosis and treatment of invasive mycosis of the CNS as well as reported cases within the pediatric neurosurgical literature and their surgical management. RESULTS: Fungal agents capable of invading the CNS can behave as aggressive entities with rapid progression manifesting as overwhelming meningoencephalitis with vascular compromise or can lead to space-occupying lesions with abscess formation which require prompt diagnosis by either laboratory identification of the components of these biological agents and their host response or by obtaining tissue specimens for microbiological identification which may not be straightforward due to prolonged culture time. CONCLUSION: Following a high degree of suspicion with prompt initiation of antifungal agents and reversal of potential immunosuppressant therapies along with neurosurgical evacuation of intracranial collections or removal of infected hardware (CSF shunts) can lead to more optimistic outcomes of these complex clinical scenarios.

Microbiology of otitis media in Costa Rican children, 1999 through 2001.

BACKGROUND: Because of the increasing number of resistant middle ear pathogens and the impact of the new conjugate Streptococcus pneumoniae vaccine, an active surveillance of the microbiology and susceptibility pattern of middle ear pathogens is required. OBJECTIVE: To study the microbiology and susceptibility pattern of middle ear pathogens obtained from Costa Rican children with acute otitis media (AOM), recurrent otitis media (ROM) and therapeutic failure otitis media (FOM). METHODS: Between 1999 and 2001 middle ear fluid (MEF) was collected from 276 Costa Rican patients. S. pneumoniae serotyping and pulsed field gel electrophoresis analysis was done on available strains. RESULTS: Among the total study population, 102 were AOM patients, 98 were ROM patients and 76 were FOM patients. Overall S. pneumoniae (88 strains) was the most common pathogen isolated followed by Haemophilus influenzae (41 strains) and Streptococcus pyogenes (10 strains). H. influenzae was the most common agent in FOM patients (P = 0.015). Beta-lactamase production was observed in 3 of 41 (7%) H. influenzae strains and 3 of 3 (100%) Moraxella catarrhalis strains. Penicillin-nonsusceptible S. pneumoniae strains were more common in FOM (64%) and ROM (63%) patients than in AOM (42%) patients (P = 0.05). S. pneumoniae serotype 19F was the most prevalent serotype, mainly within one distinct clone. CONCLUSIONS: Overall S. pneumoniae serotype 19F was the most common isolate from the middle ear fluid of Costa Rican children. Beta-lactamase-negative H. influenzae was the most prevalent in the subpopulation of patients with FOM. S. pyogenes was the third most common isolate and M. catarrhalis was uncommon.

A pilot study of single-dose azithromycin versus three-day azithromycin or single-dose ceftriaxone for uncomplicated acute otitis media in children.

BACKGROUND: The pharmacokinetic profile of azithromycin supports its use as single-dose therapy for uncomplicated acute otitis media (AOM) in children. OBJECTIVE: This study was designed to (1) compare the safety of single-dose oral azithromycin, 3 daily doses of oral azithromycin, and a single dose of intramuscular ceftriaxone for the treatment of uncomplicated AOM in children, and (2) provide preliminary efficacy data to support initiation of a larger, comparative trial of single-dose azithromycin for the treatment of uncomplicated acute otitis media in children. METHODS: In this single-center pilot study, children with uncomplicated AOM were randomly assigned to receive single-dose oral azithromycin (30 mg/kg), 3-day oral azithromycin (10 mg/kg once daily), or single-dose intramuscular ceftriaxone (50 mg/kg). Tympanocentesis was performed before administration of the first dose, and clinical response was assessed on days 14-15 and 28-30. RESULTS: Between September 1995 and May 1997, 198 children (mean age, 2.5 years) were enrolled. All of the patients were evaluable for the safety and clinical intent-to-treat (ITT) analyses, and 98 were evaluable for the microbiologic ITT analysis. On day 14-15, rates of clinical success (cure or improvement) for the 3 treatment groups were: 62/64 (97%) for single-dose azithromycin, 60/63 (95%) for 3-day azithromycin, and 61/62 (98%) for single-dose ceftriaxone. On day 28-30, the corresponding clinical success rates were 61/65 (94%), 61/66 (92%), and 62/64 (97%). For the 98 microbiologically evaluable patients, clinical success rates at day 14-15 were 28/30 (93%) for single-dose azithromycin, 31/35 (89%) for 3-day azithromycin, and 33/33 (100%) for single-dose ceftriaxone. On day 28-30, the corresponding clinical success rates were 27/30 (90%), 30/35 (86%), and 32/33 (97%). Treatment-related adverse event rates for single-dose azithromycin, 3-day azithromycin, and single-dose ceftriaxone were 10.6%, 9.1%, and 9.1%, respectively. CONCLUSION: In this pilot study comparing single-dose azithromycin, 3-day azithromycin, and single-dose ceftriaxone for the treatment of uncomplicated AOM in children, no differences were detected among the 3 regimens.

Molecular epidemiology of methicillin-resistant Staphylococcus aureus in Costa Rican children.

We collected all Staphylococcus aureus isolates from the National Children's Hospital in Costa Rica to evaluate the prevalence and molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA). Of 299 S. aureus isolates, 61% were MRSA. Most MRSA isolates (94.5%) carried SCCmec IV, and 45.6% carried Panton-Valentine leukocidin-encoding genes. The high prevalence of MRSA in this population highlights the need for improvement of antibiotic prescription and infection control measures.

Predominance of vanA genotype among vancomycin-resistant Enterococcus isolates from poultry and swine in Costa Rica.

The use of avoparcin as a growth promoter is considered to have selected for vancomycin-resistant enterococci (VRE). In Costa Rica, the use of avoparcin for poultry and swine was intensive until the product was withdrawn from the market in 2000. We evaluated the presence of VRE in poultry, swine, and cattle fecal samples obtained during 1998 and 1999. A total of 185 VRE isolates were recovered from 116 out of 893 samples. Enterococcus faecium was the most frequently isolated species (50.8%), being predominant among poultry (71.6%) and swine (37.7%) isolates, but it was not recovered from the bovine samples. The second-most-frequently-isolated species from poultry and swine, respectively, were E. durans (23.2%) and E. faecalis (21.7%). E. casseliflavus was the only species obtained from bovine samples, but it was not found among the avian isolates. An evident predominance of the vanA determinant among vancomycin-resistant enterococcal species from poultry and swine, but not from cattle, was observed and was similar to the situation in European countries before avoparcin was forbidden. The diversity of the vanA determinant in the isolates was assessed by detection of the IS1251 insertion in the vanSH intergenic region and of the IS1476 insertion in the vanXY intergenic region. However, in none of the 154 vanA+ isolates recovered in this study were those insertions detected.

Concentración mínima inhibitoria de Anfotericina B contra Candida albicans / Inhibitory minim concentration of amphotericin B for Candida albicans

El incremento en el aislamiento de Candida albicans como oportunista en inmunosupresos, y los efectos secundarios con el uso del antimicótico más efectivo que es la Anfotericina B, nos motivó a estudiar la verdadera sensibilidad de C. albicans a ese medicamento. Se introdujo una técnica recientemente desarrollada para estudios micológicos y concentración mínima inhibitoria, sólo en organismos levaduriformes, ya que subsisten problemas con la preparación de inóculos con micelios. Se estudiaron 100 cepas de C. albicans y se encontró que no había resistencia a Anfotericina B, pero sí un 25,5 por ciento con sensibilidad intermedia. Se llama la atención sobre ese inicio de desarrollo de resistencia y la necesidad de un uso más racional de la Anfotericina B.

Aislamiento de Escherichia coli 0157: H7 a partir de heces de niños con síndrome urémico hemolítico / Isolation of Escherichia coli 0157: H7 to part of feces of childrens with hemolytic-uremic syndrome

Se presenta el primer reporte en Costa Rica de aislamiento de 2 cepas de Escherichia coli 0157:H7 como causa de diarrea asociada a síndrome urémico hemolítico (SUH). Se trata de 4 casos estudidos en el Hospital Nacional de Niños de Costa Rica, procedentes de diferentes zonas del país y sin relación epidemiológica entre ellos. Se recomienda más atención en la búsqueda de esta bacteria en los casos de diarrea y sugestivos de SUH.

Primeros aislamientos de Enterobacter cloacae y Klebsiella pneumoniae productores de B-lactamasa de efecto expandido (ESBL) en Costa Rica / First insulating of endobacter cloacae and Klebsiella pneumoniae produced of B lactaminasa of to expand (ESBL) effect in Costa Rica

Se reportan los primeros casos en que se aisló Enterobacter cloacae y Klebsiella pneumoniae productores de beta lactamasa de efecto expandido(ESBL) en nuestro país. Se comenta la importancia de la multirresistencia a antimicrobianos de estas cepas cada vez más frecuentes en nuestros hospitales, y la metodología de laboratorio que debe usarse en su estudio.

Primer aislamiento clínico de Prototheca wickerhamii en Costa Rica / First clinic insulating of Prototheca wickerhamii in Costa Rica

Se presenta una revisión sobre Prototheca wickerhamii con motivo del primer caso de infección en humanos que se reporta en Costa Rica. Se trata de un caso de meningitis en recién nacidos cuyo origen parece ser la madre en quien también se aisló el microorganismo

Aislamientos de Enterococcus spp., resistentes a la Vancomicina, en muestras de heces de niños costarricenses / Insulating of Enterococcus spp., resistant a the Vancomicina, in feces of Costarrican children

Se hace referencia a la creación del género Enterococcus y sus especies importantes en patología humana así como su comportamiento ante la vancomicina y otros antimicrobianos. Se presentan los datos de las especies de Enterococcus encontradas en los estudios realizados en materia fecal de niños internados en la Unidad de Cuidados Intensivos del Hospital Nacional de Niños de Costa Rica.

Infecciones por Streptococcus pyogenes en el Hospital Nacional de Niños, 1994-1998 / infections for Steptococcus pyogenes in the Hospital Nacional de Niños, 1994-1998

Se presenta el estudio de 1193 pacientes en quienes se obtuvo cultivo positivo por Streptococcus pyogenes en diferentes tipos de secreciones. Se comenta su relación con la presencia de anticuerpos y títulos ASO, su sensibilidad a antimicrobianos y se llama la atención sobre el aislamiento creciente de esta bacteria en nuestro medio y el repunte de la fiebre reumática a nivel mundial.

Primer aislamiento de Burkholderia pseudomallei en Costa Rica / First insulating of Burkholderia pseudomallei in Costa Rica

Se menciona la creación del nuevo género Burkholderia en la familia Pseudomonaceae y se citan las especies mas importantes como agentes implicados en diversos cuadros clínicos. Se informa el primer aislamiento que se reporta en Costa Rica de Burkholderia pseudomallei, agente etiológico de la mieloidosis; se revisa su identificación en el laboratorio y su reacción a los antimicrobianos.

Experiencia con la tinción rápida para el diagnóstico de la diarrea por Campylobacter sp. y Crystosporidium sp / Rapid staining for diagnosis of diarrhea produced by Campylobacter sp and Cryptosporidium sp

Se describe el uso de la tinción con Giemsa para frotis de heces, la cual es rápida, barata y fácil de realizar y puede ser usada en el diagnóstico presuntivo de la diarrea por Campylobacter fetus ssp. jejuni y es, además, uno de los métodos usados para la detección de los ooquistes de Cyptosporidium sp. Dicha tinción, es también de utilidad en la observación de leucocitos, eosinófilos y otros protozoarios

Estudio abierto no comparativo con mupirocina en el tratamiento de pacientes pediátricos con infecciones de la piel y tejidos blandos / Open study of Mupirocin in the treatment of skin and soft tissue infections in pediatric patients

Objetive:To analyze the clínical and bacteriologicalefficacy of mupirocina in the treatment of pediatric patients with skin and solf tissue infectons. Design : Prospective, open, non-comparative clinical trial. Materials and methods: Patiens between 6 months and 12 years old with the clinical and bacteriological diagnosis of a skin of soft tissue infection were included in this trial. Material from the affected site was obtained for culture and susceptibility testing using the kirby - Bauer techique. All the patients were treated with topical mupirocin for 7 days. Follow up visits for clinical evaluations and adverse events were perform during (day 3) and at the end of therapy (day 7-8). Results: From 32 patients enrolled, 23 were considered evaluable. The initial diagnosis were impetigo (29 cases) and pyodermitis (3 cases). The ethiologic agents obtained from the 23 evaluable patients were S. aureus (14), S pyogenes (2), S. aureus and S. Pyogenes (1), Candida albicans (1) and Klebsiella (2). 87.7 porcent (13/5), Of the S. aureus strains and 100 porcent (2/2) of the S. pyoenes strains were mupirocin susceptible. The 2 klepsiella sp. strains were mupirocin resistant. Twenty of the 23 evaluable patients (87 porcent) were considered cured or improved at the end of therapy. Conclusion: The results of this clinical trial, together with other larger trials, suggest that topical mupirocin is a valid and safe alternative for this treatment of pediatric patients with skin and soft tissue infectious

Campylobacter fetus ssp. jejuni, Aeromonas hydrophila, bacterias helicoidales y coronavirus en intestino murino / Campylobacter fetus ssp. jejuni, Aeromonas hydrophila, helicoidal bacteria and coronavirus in the murine intestine

Se analizó la microflora intestinal de 28 ratones, criados en un bioterio y de 6 ratas silvestres. De cada aninal se extrajo el contenido intestinal y se observó al microscopio de contraste de fases y al microscopio electrónico de transmisión. También, se hicieron cultivos en agar de Butzler y agar aeromonas, que fueron incubados en microaerobiosis a 37graus centígrados, durante cinco días. A partir del contenido intestinal de tres de los ratones y de dos de las ratas se observó bacterias helicoidales, con 8 a 11 fibras periplásmicas y ramilletes terminales de 8 a 11 estructuras similares a flagelos. También, en una de esas ratas se observó partículas similares a coronavirus. En los cultivos de dos de los ratones se aisló Campylobacter fetus ssp. jejuni y de dos de las ratas se aisló Campylobacter fetus ssp. jejuni y de dos de las ratas se aisló A eromonas hydrophila

Estudio de sensibilidad de los bacilos Gram negativos a la ceftriaxona / Gram-negative bacilli sensibitily to cephtriaxone

La ceftaxona es una nueva cefalosporina con un amplio espectro de actividad antimicrobiana, que posee una excelente actividad contra los miembros de la familia Enterobacteriaceae, pero mínima contra Pseudomonas aeruginosa. Este estudio es el primer informe de sensibilidad bacteriológica a la ceftriaxona en términos de Concentración Mínima Inhibitoria hecho por el método de dilución en agar, en Costa Rica. El 100 por ciento de las cepas de la familia Enterobacteriaceae fueron sensibles a < 8 ug/ml. Pseudomonas aeruginosa fue resistente en un 90 por cienbto a concentraciones mayores de 16 ug/ml. La mayoría de los miembros de la familia Enterobacteriaceae son inhibidos por 0,03 ug/ml o menos de ceftriaxona

Primer caso de enterocolitis aguda necrotizante producida por Clostridium difficile en Costa Rica / First case of necrotizing acute enterocolitis by Clostridium difficile in Costa Rica

Se describe el caso de un niño con enterocolitis aguda necrotizante (EAN), que falleció cuatro horas después de su ingreso al Hospital Nacional de Niños. Se aisló Clostridium difficile a partir de un hemocultivo y un coprocultivo. Este es el primer caso en Costa Rica en que se describe a C. difficile como productor de EAN