Variable Very-High-Energy Gamma-Ray Emission from the Microquasar LS I +61 303

Microquasars are binary star systems with relativistic radio-emitting jets. They are potential sources of cosmic rays and can be used to elucidate the physics of relativistic jets. We report the detection of variable gamma-ray emission above 100 gigaelectron volts from the microquasar LS I 61 + 303. Six orbital cycles were recorded. Several detections occur at a similar orbital phase, which suggests that the emission is periodic. The strongest gamma-ray emission is not observed when the two stars are closest to one another, implying a strong orbital modulation of the emission or absorption processes.

[Criteria of low risk of mortality in children with neutropenia and fever during cancer chemotherapy]

To validate the use of a lower-risk mortality profile in pediatric febrile neutropenia during anticancer therapy and to evaluate the efficacy of a sequential parenteral-oral antibiotic treatment for these children, a prospective study was conducted between May 1997 and December 1999. During this period 247 episodes in 215 patients were included in the present study. Children with neutropenia (ANC < 500/mm3) and fever (> 38 degrees C) due to anticancer therapy were eligible for the study if they presented the following lower-risk conditions: absence of severe co-morbidity factors, good clinical condition, no risk clinical foci, no bacteremia, and responsible parents. They were initially treated with inpatient parenteral short course of ceftriaxone and amikacin followed by ambulatory oral cefixime or ciprofloxacin to complete 7 days. Mean age was 64 (range: 8-200) months. The most common underlying malignant disease was acute lymphoblastic leukemia in 48% (118) of cases and 57% (141) of patients had an indwelling central venous catheter. Clinical evidence of infection was found in 47% (122) of children and the most common site was the upper respiratory tract (81%). Mean period of fever was 1.1 days (r: 1-8) and the duration of neutropenia was 3.9 days (r: 1-9). Sixty-one% (150) of children was discharged with neutropenia. Mean time of hospitalization was 1.5 days. Four clinical failures were detected (1.6%). They all were satisfactorily treated with a secondary treatment and none underwent any major complications or died. The lower-risk profile used was safe and the sequential antibiotic therapy was adequate to manage febrile neutropenia in this subset of children.

Oral ciprofloxacin in the management of children with cancer with lower risk febrile neutropenia

BACKGROUND

Recent reports and a previous randomized trial conducted at the authors' institution suggested that a lower risk subset of children with febrile neutropenia under chemotherapy might benefit of an oral antibiotic outpatient approach.

METHODS

The objective of this study was to test the efficacy of oral ciprofloxacin in the treatment of lower risk febrile neutropenia (LRFN) in children treated for malignant diseases. From November 1998 to December 1999, 93 episodes of LRFN in 87 children (median age, 5.5 years; range, 0.9-15.8 years) were included in a prospective randomized controlled single institution trial. Inclusion criteria included fever (> 38 degrees C), severe neutropenia (absolute neutrophil count, < 500/mm(3)), and lower risk features (e.g., absence of severe comorbidity factors, good clinical condition, negative blood cultures, control of local infection, prediction of a period of neutropenia less than 10 days after admission, and compliant parents). After 24 hours of a single intravenous ceftriaxone (100 mg/kg) plus amikacin (15 mg/kg) and completed risk assessment workup, patients were discharged and randomly allocated to two groups. Group A (48 episodes) received ciprofloxacin 20 mg/kg/day orally (p.o.) every 12 hours for 6 days. Group B (45 episodes) received intravenous ceftriaxone plus amikacin for 2 days more followed by cefixime (8 mg/kg/day p.o.) every 24 hours for 4 additional days. Failure was defined as the need of a second hospitalization during the same episode.

RESULTS

Most of the patients (59% in Group A and 52% in Group B) were treated for malignant solid tumors. Fifteen (31%) children in Group A and 15 (33%) in Group B presented with fever of unknown origin (P value was not significant). No significant differences were found in sites of initial infection between both groups. Overall results in this study were excellent. Only one patient with respiratory failure was detected in Group B, who did well with secondary treatment.

CONCLUSIONS

In febrile neutropenic children after anticancer therapy and lower risk features, oral ciprofloxacin for 6 days after 24 hours of intravenous ceftraxione plus amikacin appears to be as efficacious as intravenous ceftriaxone plus amikacin for 2 days more followed by cefixime for 4 additional days. These results contribute to strengthen the concept of LRFN.

[Impact of the primary health care reform on the use of the hospital emergency services]

BACKGROUND

The overutilization of the hospital emergency areas (HEA) in recent years has been related to an inadequate functioning of the primary health care and can be corrected by the implementation of the primary health care reform.

MATERIAL AND METHODS

Home interview of a sample of residents of the city of Mataró (Barcelona, Spain), where the primary health care reform affects to four of the seven basic health areas. Collection of information on health care utilization and attitudes to its use.

RESULTS

Of the 1,974 studied subjects 27% (CI 95%, 25-29) reported to have used the HEA in the former year, and the frequency of visits was 0.48 (CI 95%, 0.44-0.54) per person. For the 1880 beneficiaries of the national health system, these results were somewhat lower between the users of reformed centres (27%, 0.46) than those of non-reformed centres (30%, 0.50) (p = NS); differences were attributed mainly to adult women. Users of reformed centres expressed more preference for the ambulatory in case of a non-severe emergency (37% and 17%; p < 0.0001) and consulted more often before going to the HEA (17 and 10%; p = 0.03). Among the reasons to go to the HEA, users of the reformed model perceived less necessity of an immediate action (43 and 52%; p = 0.05) and greater time barriers with the basic health areas (23 and 15%; p = 0.04).

CONCLUSIONS

In spite of the lack of overall differences in the use of HEA between users of reformed centres and non-reformed centres we observed a lower utilization in some age and sex groups from reformed centres. Some elements of the demand of the HEA are more appropriate and attributed to the primary health care reform. However, the reasons prompting to use the HEA show that an unjustified utilization is still done, independently of the primary health care model.