Infections in Children with Neoplastic Disease

PURPOSE: Infection is a major complication in patients with malignant disease. This study was performed to identify the causes and the etiologic agents of febrile infections and to characterize the clinical courses including the response to antimicrobial agents inpediatric cancer patients. METHODS: This study reviewed 274 febrile episodes occurring in 163 children with neoplastic disease which were indentified prospectively at Seoul National University Children's Hospital from January, 1991 to June, 1993. Neutropenia was defined as [granulocyte+band from] < or = 500mm(3). Each febrile episode was classified as a microbiologically documented infection(MDI), a clinically documented infection(CDI), and a probale infection(PI). The responses to initial antimicrobial atents were categorized into improvement, temporary improvement, failure, and not evaluable according to period to defervescence. RESULTS: Seventy seven percent of the febrile epidodes developed in neutropenic state. MDI were 98(36%), CDI 92(34%), and PI 84(30%) episodes. Bacteria were isolated in 75%, viruses in 13% and fungi in 11% of MDI. Fifty two episodes(19% of all) were associated with a bacteremia, and focal infections were indentified in 63% of bacteremia. The most frequent organisms causing MDI were E. coli(22%), K. pneumoniae(15%), S.epidermidis(7%). The great majority of infections other than bacteremia ocurred in the lung(32%), oral cavity(17%), skin and soft tissue(13%), and urinary tract(11%). The frequency of antimicrobial resistance of causative organisms was high. The responses to initial antimicrobial agents were improvement in 49%, temporary improvement in 13%, and failure in 38%. Patients with bacteremia responded less well than those with other categories. Mortality was 7% of total episodes. All of the fatal cases occurred in neutropenia and all but one had hematologic malignancies. CONCLUSIONS: This study documents the etiology and the type of infections and the responses to antimicrobial therapy in children with neoplastic diseases. The changes of causative agents and antimicrobial resistance should be considered in therapeutic strategies of cancer infection.

Pharmacokinetics of Gentamicin and Amikacin in Korean Children with Normal Renal Function

We analysed retrospectively pharmacokinetic parameters of gentamicin and amikacin in 44 and 58 Korean pediatric patients, respectively, with normal renal function. Pharmacokinetic parameters were calculated from two concentrations in serum by method of Sawchuck. There was wide individual variation in peak serum concentrations of gentamicin and amikacin, Administration of the usually recommended doses yielded subtherapeutic concentrations in 47% and 82%, respectevely, of patients in the peak concentrations of gentamicin and amikacin. The volumes of distribution of gentamicin and amikacin in children of over 1 year of age were 0.37+/-0.13L/kg and 0.41+/-0.13L/kg which are greater than those reported from the western countries. We conclude that the wide individual variation and high frequency of subtherapeutic levels in the peak concentrations of gentamicin and amikacin obtained by usually recommended dosage as well as the narrow safety margin of these drugs necessitate monitoring of serum concentration and adjustment of individual dosage regimen early in the course of treatment with aminoglycosides.

The Significance of Bacteriologic Examination in the Childhood Tuberculosis

We reviewed retrospectively the medical records of 229 cases of tuberculosis, who had been diagnosed clinically and admitted to the departmet of pediatrics, Seoul National Univeristy Children's Hospital, during the period of 6 years from October, 1985, to October, 1991. Patients with tuberculosis occupied 1.2% of the hospitalized patients. Forty-three percent of the patients were under 3 years of age. Principal involvement sites were; the lungs-26.7%, the pleura-18.8%, the central nervous system-30.6%, the abdomen-7.4%, the genito-urinary tract-1.3%, the bones and joints-3.0%, the lymph nodes-3.0%. In 147 patients with extrapulmonary tuberculosis, pulmonary lesions suggestive of tuberculosis were found in 33.3%, 9.2% of the patients had miliary dissemination. In pulmonary tuberculosis and extrapulmonary tuberculosis with lung involvement, the gastric aspirates were positive for acid-fast bacilli (AFB) by Ziehl-Neelson stain in 6.1%, and grew M. tuberculosis in 43.5%. The sputa were positive for AFB in 12.9%, culture in 18,5%. In extrapulmonary tuberculosis, the specimens from involved sites were positive for staining in 5.7%, culture in 19.3%. Twenty-one isolates of M. tuberculosis were submitted to susceptibility to 11 antituberculous drugs. Resistance to one or more drugs were found in 38.1% of the isolates. INH resistance was found in 33.3%, RFP resistance in 28.6%. We conclude that bacteriologic documentation of tuberculosis is possible in significant proportion of the pediatric patients, drug resistance of M. tuberculosis isolated from the children is high in Korea, and continued monitoring of drug resistance is required.