Assessment of anaerobic blood cultures in pediatric oncology patients.

INTRODUCTION: The routine use of a single aerobic bottle for blood culture in pediatric patients has become commonplace, as anaerobic bacteria are not frequently involved in clinically significant infections. The aim of this study was to assess the usefulness of routinely performing anaerobic blood cultures in pediatric oncology patients. METHODS: Prospective study was conducted on pediatric (<18 years) patients affected with febrile syndrome after receiving chemotherapy for hematological or solid malignancies. Samples were inoculated into pediatric aerobic and standard anaerobic bottles (BacT/Alert automatic system). Strains were considered clinically significant, or deemed as contaminants, depending on isolation circumstances and clinical criteria. RESULTS: A total of 876 blood cultures from 228 patients were processed during the 21-month study period (January 2014 to September 2015). Baseline diagnosis included 143 solid tumors and 67/18 cases of leukemia/lymphoma. Bacterial growth was detected in 90 (10.2%) blood cultures for 95 different isolates, of which 62 (7.1%)/63 isolates were considered clinically significant. Among the latter, 38 (60.3%) microorganisms grew in both aerobic and anaerobic bottles, 18 (28.6%) only in aerobic bottles, and 7 (11.1%) only in anaerobic bottles. Gram-negative bacilli (33; 52.4%), mainly from the Enterobacteriaceae family, were the most frequently isolated microorganisms. Overall, only 3 out of 90 isolates (3.3%) were strict anaerobes (Propionibacterium acnes), and all of them were deemed contaminants. CONCLUSION: Strict anaerobes did not cause significant infections in febrile pediatric oncology patients, and anaerobic blood culture bottles offered no additional advantages over aerobic media. Our results suggest that routine blood cultures should be solely processed in aerobic media in this group of patients.

[Etiology and clinical course of urinary tract infections in infants less than 3 months-old]. / Etiología y curso clínico de la infección del tracto urinario en los lactantes menores de 3 meses.

BACKGROUND: Infants less than 3 months of age with urinary tract infection are usually hospitalized. Recent studies show that a less aggressive management for those patients aged ≥ 29 days may be feasible. OBJECTIVES: To determine the complication rate in infants<3 months of age with urinary tract infection, and to identify the causative agents and their antibiotic susceptibility. METHODS: A retrospective study was conducted on infants<3 months of age with positive urinalysis results, together with a positive urine culture from a catheterized specimen and seen in the Emergency Department from 2007 to 2012. Demographics, clinical and microbiology (microorganism isolated and antibiotic susceptibility) data were collected. The complications rate (bacteremia, bacterial meningitis, renal abscess, surgical intervention, Intensive Care Unit admission, or death) were calculated for the overall sample and for different age groups (<29, 29-60, and 61-90 days). RESULTS: A total of 460 patients are included; 137 (29.8%)<29, 166 (36.1%) 29-60, and 157 (34.1%) 61-90 days of age. Twenty four (5.4%; 95% CI: 3.6-7.8) had bacteremia; 15 (10.9%; 95% CI: 6.7-17.3) were<29 days; 8 (4.9%; 95% CI: 2.5-9.4) were 29-60 days, and one (0.7%; 95% CI: 0.1-3.7) was 61-90 days of age (P<.001). One neonate (0.8%; 95% CI: 0.1-4.1) had bacterial meningitis, and 2, renal abscess. Escherichia coli was the common pathogen identified (87.2%) in the urine culture, with a susceptibility to amoxicillin-clavulanate, gentamicin, and cefixime of 89.2, 97.0, and 96.0%, respectively. CONCLUSION: Complications are low in infants<3 months of age with UTI, especially in those ≥ 29 days of age. The identification of patients at very low risk for complications would allow a less aggressive management. Escherichia coli antibiotic susceptibility remains stable, but continuing careful surveillance is essential to optimize empirical antibiotic treatment.

Aeromonas hydrophila folliculitis associated with an inflatable swimming pool: mimicking Pseudomonas aeruginosa infection.

Aeromonas species are ubiquitous, facultative, anaerobic, gram-negative flagellated rods, mainly found in aquatic ecosystems worldwide. Skin and soft-tissue infections, including cellulitis and wound infections, are the second most frequent location of isolations of Aeromonas spp. in clinical samples, after the gastrointestinal tract. All three major Aeromonas species (A. hydrophila, A. caviae, and A. veroni biotype sobria) have been associated with wound infections, but A. hydrophila predominates. Typically, infection occurs after trauma and subsequent exposure to contaminated fresh water or soil. However, Aeromonas folliculitis has been rarely reported. We report the first two pediatric cases of Aeromonas hydrophila folliculitis associated with the use of recreational water facilities that clinically and epidemiologically mimic Pseudomonas folliculitis. Clinical and microbiological studies may be necessary to clarify the role of Aeromonas spp. in this newly-reported infection.

Osteoarticular infections: Blood as a determinant factor in the isolation of Kingella kingae.

We assessed the capacity of Kingella kingae to grow in blood culture bottles (BCB), taking into account the concentrations of the microorganism and blood in the culture medium. An initial suspension (McFarland 0.5) of 32 strains of K. kingae was serially diluted. One mL of the initial suspension and 1 mL of the subsequent dilutions were inoculated in two BCB, together with 1 mL of human blood in the 2nd BCB. Also, 1mL serial dilutions of human blood were added to BCBs previously inoculated with 1 mL of K. kingae dilution 1/104. In non-blood-supplemented BCB, 23 strains grew with the initial suspension and only one with the first processed dilution, as compared to all strains with the initial suspension and the 3 first dilutions, 22 with the 4th dilution, and one with the 5th dilution in blood-supplemented BCB. In BCB inoculated with K. kingae dilution 1/104 and decreasing concentrations of human blood, all strains grew with blood dilutions 1/2 and 1/4, 26 with dilution 1/8, 19 with dilution 1/16, 10 with dilution 1/32, and none with dilution 1/64. Increasing time to positivity was observed with both decreasing bacterial (p = .001) and blood concentrations (r = -0.632, p < .0001). The addition of human blood was essential to boost the growth of K. kingae in BCB. If replicated in vivo, these findings would increase the isolation of fastidious K. kingae organisms from pediatric osteoarticular exudates.

Invasive disease by Streptococcus pyogenes: patients hospitalized for 6 years. / Enfermedad invasiva por Streptococcus pyogenes: ingresos durante 6 años.

INTRODUCTION AND OBJECTIVE: The last years an increase of severe cases of invasive disease (ID) due to Streptococcus pyogenes or streptococcus b-hemolytic group A (SGA) had been detected. The aim of this study was to analyze the epidemiology and the clinical features of ID due to SGA in a tertiary Pediatric Hospital. MATERIAL AND METHODS: Retrospective study in a Pediatric hospital, of all in-patients with final diagnosis of ID due to SGA during 6 years (2009-2014). To consider ID, SGA had to be isolated in sterile samples; in patients with fascitis necroticans in skin samples or in any sample in patients with the diagnostic of Streptococcal Toxic Shock Syndrome (STSS). The SSTS was defined as hypotension and at least 2 of these criteria: renal failure, hepatic failure, acute respiratory distress, tissue necrosis or desquamative erythematous rash. Demographic data, type of infection, risk factors, clinical presentation, analytical data at admission, treatment, need for admission to a pediatric intensive care unit, microbiological data, hospital stay and evolution were collected. RESULTS: Fifty-two (52) cases were included (12/10,000 of all inpatients); 3 years-old was the medium age (p25-75: 1.4-6.9 years); 28 (53.8%) were boys. Fourteen patients (26.9%) had risk factors. Fever was the major symptom (51 patients, 98.1%). The skin lesions were the most frequent clinical manifestations found (21; 40.4%). In 50 (96%) cases, SGA was isolated in at least one sterile sample. Skin and soft tissue infections were diagnosed in 14 patients (26.9%), 14 (26.9%) pneumonias, 12 (23.1%) bones and joints infections, 10 (19.2%) SSTS, 6 (11.5%) occult bacteremia, 4 (7.7%) meningitis and 2 (3.8%) sepsis. Surgery was required in 18 cases (34.6%) and 17 patients (32.7%) needed intensive care. The medium hospital stay was 9.5 days (p25-75: 8-15 days). Three patients presented sequels and one patient died. CONCLUSION: The ID due to SGA was a rare but serious reason for hospital admission. Skin and soft tissue infections, and pleuroneumonia were the most common forms of ID. The mortality of our sample was low despite the serious clinical manifestations.

[Bacteraemia risk criteria in the paediatric febrile neutropenic cancer patient]. / Criterios de riesgo de bacteriemia en el paciente oncológico neutropénico febril pediátrico.

INTRODUCTION: Cancer patients with febrile neutropenia are not a homogeneous group with respect to risk of bacterial infections. Some authors have proposed that febrile cancer patients with low risk factors of bacteraemia could be managed at home with domiciliary antibiotic treatment. The objectives are: to determine the incidence of bacteraemia in our cancer patients who have febrile neutropenia; and to identify the low-risk factors so that the patients can be managed at home using domiciliary antibiotic treatment. MATERIAL AND METHODS: Clinical review of paediatric haemato-oncology disease admitted to our hospital in 2002 suffering from febrile neutropenia. RESULTS: We describe a total of 62 episodes of febrile neutropenia in 30 patients; 24 episodes in haematology patients and 38 episodes in oncology patients. High-risk criteria are age <1 year, poor bone-marrow recovery, chemotherapy within 10 days of the episode, rapid fast neutropenia, leukaemia in relapse, uncontrolled solid cancer, and cardiac or nephrology disease. Based on the number of risk-factors, patients with two or less risk-factors have an incidence of bacteraemia of 6.7% (1/16) and patients with three or more risk factors have an incidence of bacteraemia of 32.6% (15/46); p<0.05. CONCLUSIONS: Incidence of bacteraemia is similar to the reviewed literature; probability of bacteraemia increases with the number of individual risk factors, and patients with low risk of bacteraemia could be managed on an outpatient basis using domiciliary antibiotic treatment.

Isolated congenital nail candidiasis: report of 6 cases.

Congenital candidal infection usually presents as skin rash but it can also affect skin appendages. Nail involvement in congenital candidiasis is rare and has been usually associated with cutaneous lesions. We report 6 cases of congenital candidiasis limited to nail plates that had favorable outcome.