Invasive fungal diseases in children with hematologic disorders.

OBJECTIVE: Fungal infection is a significant problem, causing of infective deaths of leukemic patients. The situation in developing countries is not well documented. The purpose of this study was characterizing IFD by analyzing data retrospectively to determine the incidence, predisposing factors, diagnostic methods, efficacy of treatment, and the outcome in pediatric patients with hematological disorders. METHODS: There were 160 children with leukemia (22 AML, 129 ALL) and 9 with aplastic anemia (AA). The diagnostic criteria for IFD were defined according to the EORTC/MSG, 2008. IFD was classified as proven or probable. Empiric antifungal treatment with L-AmB was commenced by day 5-7 of persistent fever. Patients with invasive aspergillosis (IA) who were refractory to primary treatment were commenced on voriconazole (VCZ). Salvage therapy as combination of VCZ and caspofungin was given to those with progressive infection. RESULTS: The incidence of IFD was found 23 (14.3%). 19 with leukemia (14 ALL, 5 AML) and 4 with aplastic anemia were diagnosed as IFD. IA was the dominant cause of infection (n=17) and the rest (n: 6) had candidiasis. Ten children had "proven" infection and 13 children were defined as "probable". The most frequent site of infection was lungs. In our series, the most frequently used diagnostic methods were clinical findings (100%) and radiologic methods (84%). The success rate of treatment for candidiasis and IA were found 60%, 71% respectively. IFD related death rate was found 30%. CONCLUSION: IFD is still a major morbidity and mortality reason in children with hematologic disorders. However, the availability of new antifungal treatments and diagnostic tests will improve the survival rates in these children.

Efficacy of primary hepatitis B immunization in children with acute lymphoblastic leukemia.

BACKGROUND: Children with acute lymphoblastic leukemia (ALL) carry a high risk of hepatitis B virus (HIV) infection. The present study was conducted to see if prior routine hepatitis B vaccine received as a part of national immunization program could prevent HBV infection in these children. METHODOLOGY: Ninety-six children with ALL were screened for HBV. Children were divided into three groups according to their initial HBV serology; previously vaccinated children (Group I) (n=34) previously unvaccinated and seronegative children (Group II) (n=56),and unvaccinated but HBsAg negative and anti-HBs positive children (group III) (n=6). Sixty-seven of 96 (69.7%) children received vaccination. The schedule was initiated during the third month of maintenance therapy and each course consisted of three doses given at one month interval. RESULTS: Anti-HBs seroconversion following the first course of three doses of hepatitis B vaccination in group I, II and III was 57%, 33% and 100%, respectively. It increased to 97% in Group I, 62.5% in Group II, 100% in Group III. HBsAg positivity was found in 11 children (11.5%) and all of them developed chronic hepatitis B. Ten of them were in Group II whereas only one child was in Group I (P<0.04). CONCLUSION: This data reveals that routine HBV vaccination within the national immunization program plays an important role in decreasing subsequent hepatitis B infection in children with ALL.

The influence of risk factors in promoting thrombosis during childhood: the role of acquired factors.

Thrombo-embolism in childhood is a multifactorial disorder. The present study is a case-control study that investigated the role of genetic and acquired risk factors in 60 children with thrombosis and compared the results with the controls. Acquired and inherited risk factors precipitating thrombosis were present in 75 and 40% of the thrombotic children, respectively. The most frequent acquired risk factor was infection (58%). Of the genetic factors, factor V G20210A was the most common (38%). The comparison of the genetic and acquired risk factors in thrombotic versus nonthrombotic settings identified that acquired factors played a more significant role in causing thrombosis (OR:14.44; 95% CI: 7.05-29.94, p < .001). This study has clearly suggested that the prevention of acquired risk factors, particularly infection, could decrease the risk of thrombosis in pediatric cases.

Increased risk of chronic hepatitis in children with cancer.

BACKGROUND: There is a risk of viral hepatitis for children with cancer. Both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in countries with high prevalence cause major problems in the management of cancer patients. In this study, we evaluated the incidence and chronicity of HBV and HCV infections in children with malignant diseases receiving chemotherapy. PROCEDURE: One hundred ninety-eight children with cancer (mean age = 7.5 +/- 2.5 years) and 100 healthy children as a control group were screened for HBV and HCV. Liver function tests, the number of transfusions, HBV and HCV serology were regularly monitored. In seropositive children, HBV-DNA and HCV-RNA were measured. Chronic hepatitis was defined as having an alanine aminotransferase (ALT) level three times of upper normal limit, positive HBV and HCV antigenemia for longer than 6 months. Liver biopsies were performed in all children with chronic hepatitis. The relationship between the chronic hepatitis and study parameters was statistically analyzed. RESULTS: HBsAg positivity, anti-HCV, and mixed (HBV and HCV) infection were found in 11.6, 5.5, 2% of children, respectively. Most HBV infected children developed chronic hepatitis (48%) while 26 and 21.7% became carriers and immune, respectively. One died of acute fulminant HBV hepatitis. Of HCV infected children, 63.6% also had positive HCV-RNA. Four children with mixed infection (100%) all progressed to chronic hepatitis. In this setting, chronic hepatitis was observed in 22 of 38 infected children (57.8%). The majority had leukemia and lymphoma. Children with HBsAg antigenemia developed chronic hepatitis in shorter time than HCV positive children (median 13 months vs. 51 months, P < 0.001). CONCLUSION: We observed an increased incidence of chronic hepatitis and even mortality due to HBV infection. This suggests that HBV and HCV infections are serious causes of morbidity and mortality in children with cancer.