Single-daily ceftriaxone plus amikacin versus thrice-daily ceftazidime plus amikacin as empirical treatment of febrile neutropenia in children with cancer

OBJECTIVE

Empirical antibiotic treatment for febrile neutropenic patients has been the mainstay of treatment for many years. Beta-lactam antibiotics and aminoglycosides have been the most frequently used drug combination. The purpose of this study was to evaluate the efficacy, safety, tolerance and costs of single-daily ceftriaxone plus amikacin versus thrice-daily dose of ceftazidime plus amikacin.

METHODOLOGY

One hundred and ninety-one episodes of fever and neutropenia in 128 patients from October 1997 to December 1998 were included in a prospective, open-label, single-centre study. Patients were randomly assigned to either treatment group and evaluated as successes or failures according to defined criteria. Daily assessments were made on all patients and all adverse events recorded. Univariate and multivariate analysis of outcomes and a cost analysis were carried out.

RESULTS

There were 176 evaluable patient-episodes with 51.1% in the single-daily ceftriaxone-amikacin group and 48.9% in the ceftazidime-amikacin group. There were 50 positive blood cultures: 12 Gram-positive bacteria, 33 Gram-negative bacteria and five fungi. Pseudomonas aeruginosa (P. aeruginosa) accounted for 14% of total isolates. The overall success rate was 55.5% in the ceftriaxone group compared to 51.2% in the ceftazidime group (P = 0.56). Mean time to defervescence was 4.2 days in the single-daily group and 4.3 days in the thrice-daily group. There were nine infection-related deaths; five in the single-daily ceftriaxone group. The daily cost of the once-daily regime was 42 Malaysian Ringgit less than the thrice-daily regime. There was a low incidence of adverse effects in both groups, although ototoxicity was not evaluable.

CONCLUSIONS

The once-daily regime of ceftriaxone plus amikacin was as effective as the 'standard' combination of thrice-daily ceftazidime and amikacin with no significant adverse effects in either group. The convenience and substantial cost benefit of the once-daily regime will be particularly useful in developing countries with limited health resources and in centres with a low prevalence of P. aeruginosa.

Blood pressure values in healthy Malaysian children aged 6-12 years

Blood pressure examination was done manually in 1756 healthy school children aged 6-12 years. Korotkoff 1 represented the systolic blood pressure (SBP) and Korotkoff 5 was taken as the diastolic blood pressure (DBP). Blood pressure percentile charts were then drawn up based on age group and sex regardless of ethnicity. There was a significant correlation between both SBP and DBP to increasing height, weight and body mass index.

Age, sex, haemoglobin level, and white cell count at diagnosis are important prognostic factors in children with acute lymphoblastic leukemia treated with BFM-type protocol

The presenting features and treatment outcome for 575 Malaysian children (< or = 12 years of age) with newly diagnosed acute lymphoblastic leukemia (ALL), admitted to the University Hospital, Kuala Lumpur, Malaysia between 1 January 1980 and 30 May 1995 were evaluated to determine their prognostic significance. Two-year overall survival was achieved in 67 per cent of all patients and 55 per cent of patients were relapse-free at 2 years. All except 10 patients, with identified French-American-British L3 morphology were treated with the modified Berlin-Frankfurt-Munster 78 treatment protocol. Univariate analyses of failure rate conferred age, sex, white cell count and hemoglobin level as potentially significant prognostic factors. All four presenting features retained their prognostic strength in a multivariate analysis. Race, platelet count, morphological subtype, liver/spleen size, lymphadenopathy, central nervous system and mediastinal mass involvement did not show any significant effect on treatment outcome. The 2-year survival rate was significantly different with regard to age, white cell count and hemoglobin level. However, sex was not significantly related to overall survival. These prognostic factors may have implications on future stratification of risk-adjusted initial treatment in the management of childhood ALL. Our analysis of Malaysian children is similar to what could be predicted based on previous studies in other populations.

Characterization of a strain-specific monoclonal antibody to hepatitis delta virus antigen

Sequences of the hepatitis delta virus (HDV) vary to different degrees among isolates. A monoclonal antibody, designated as HP6A1, against the antigen of HDV (HDAg) has been characterized for its specificity. HP6A1 bound to HDAg of isolate 25 (genotype I) that was used for immunization, but not to others of both genotypes I and II. The epitope recognized by HP6A1 was then determined by a phage library displaying various heptapeptides. A consensus peptide deduced has the best match with that of residues 4-10 of HDAg (isolate 25). To confirm the phage mapping result, Escherichia coli recombinant proteins containing different lengths and various segments of HDAg (isolate 25) were constructed. The shortest HDAg segment contained in the fusion protein that reacted with HP6A1 was residues 1-10. When this peptide was added to the N-terminus of a heterologous protein engineered for eucaryotic expression, the fusion protein was detected by HP6A1. It is concluded that HP6A1 recognizes an epitope located at the N-terminus of HDAg (isolate 25). Since viruses of quasi-species exist in natural infections, a question of how different viral strains interact in vivo remains to be explored. The highly specific MAb opens a possibility to examine the fate of one strain in the presence of other related species in a cell transfection system.

Clinical features and treatment outcome of children with myeloid antigen coexpression in B-lineage acute lymphoblastic leukemia: a study of 151 Malaysian children

The purpose of the study was to evaluate the incidence of myeloid antigen coexpression and its prognostic significance in childhood acute lymphoblastic leukemia (ALL) in Malaysia. A retrospective study was conducted of all ALL cases (< or = 12 years old) diagnosed and treated in University Hospital, Kuala Lumpur, Malaysia between 1 January 1992 and 30 May 1995, with available immunophenotype data. Presenting features and treatment outcome of 39 B-lineage ALL patients with myeloid antigen coexpression (My+B) were compared with 112 B-lineage ALL patients without myeloid antigen coexpression (My-B) for similarity in demographic, clinical and laboratory features and their treatment outcome. My+B and My-B patients were treated with a uniform treatment protocol. Myeloid antigen coexpression was defined as more than 30% isolated leukemic cells positive for CD13 and/or CD33. The ages at diagnoses ranged from 2 months to 12 years. Median age was 4 years. The incidence of myeloid antigen coexpression was 23 per cent. Univariate analyses showed that presenting features were similar between My+B and My-B with regard to age, sex, race, FAB morphology, white cell count, hemoglobin level, platelet count, liver/spleen size, central nervous system or mediastinal involvement, presence of lymphadenopathy, and proportion of blast cells detected in the marrow. Treatment outcome were not significant between the two groups. The 2-year event free survival was achieved in 44 per cent of My+B and 57 per cent of My-B (p = 0.11). The 2-year overall survival rates were 62 per cent for My+B vs. 77 per cent for My-B (p = 0.08). This study demonstrates that myeloid antigen coexpression is fairly common and constitutes 23 per cent of childhood ALL within the Malaysian population and that it is not an adverse risk factor in childhood ALL.

Successful treatment of Candida albicans endocarditis in a child with leukemia--a case report and review of the literature

Candida species is now being increasingly recognised as an important cause of endocarditis especially in immunocompromised patients. A case of Candida albicans endocarditis in a child with acute lymphoblastic leukemia (ALL) is reported. The child did not have a central venous catheter at any time. Treatment consisted of intravenous amphotericin B and fluconazole for 3 weeks followed by oral fluconazole for 2 weeks. No surgical resection was necessary. We highlight here the importance of echocardiography in the management of prolonged febrile neutropenia and discuss the dilemma of continuing chemotherapy in such patients.

Cure of beta-thalassaemia major by umbilical cord blood transplantation--a case report of Malaysia's first cord blood transplantation

A 25-month-old boy with beta-thalassaemia major was presented with an opportunity for umbilical cord blood transplantation when his unborn sibling was diagnosed in utero to be a beta-thalassaemia carrier and also human leucocyte antigen compatible. A barely adequate amount of cord blood was collected at the birth of his sibling and infused into the patient after appropriate chemo-conditioning. Engraftment occurred without major complications. The subject is now alive and well 9 months post-transplant, thus marking our first success in umbilical cord blood transplantation.

Treating high risk childhood solid tumours with autologous peripheral blood stem cell transplantation--early experience in University Hospital, Kuala Lumpur

Although survival rates for childhood cancers have improved steadily over the past two decades, the outcome for advanced stage solid tumours remains poor. Many of these tumours are chemosensitive but most chemotherapeutic regimens are limited by their haematological toxicities. Much attention is now focused on mega-dose chemotherapy followed by stem cell rescue in the treatment of disseminated neuroblastoma, rhabdomyosarcoma, germ cell tumour and brain tumours. There is a preferential shift towards peripheral blood stem cell transplantation instead of bone marrow transplantation because of its advantages of faster engraftment, decreased transfusion and antibiotic usage and shortened hospitalisation. This mode of therapy is dependent on technologies including peripheral blood stem cell harvesting, cell cryopreservation and thawing. These technologies were recently made available in Malaysia and we report our early experience.

Presenting features and treatment outcome of 78 Malaysian children with neuroblastoma

To study the distribution of presenting features and their prognostic significance in neuroblastoma treated in a single institution in Malaysia. A retrospective study was made of 78 neuroblastoma cases diagnosed and treated in the University Hospital, Kuala Lumpur, Malaysia between June 1982 and February 1997. Diagnosis was established by standard histological criteria. The presenting features were evaluated for their distribution and prognostic influence. Disease-free survival from diagnosis was the outcome variable of interest. The ages ranged from 0.1 to 11 years old (median: 3 years old). The tumor originated from the adrenal glands in 83% and the majority of cases presented in advanced stage (stage III 22%, stage IV 66%). Bone marrow was the commonest site of distant metastasis occurring in 45% of patients. The main presenting signs and symptoms in decreasing order were pallor, fever, abdominal mass, weight loss, and bone/joint pain. Univariate analysis conferred age, initial stage and Hb level as significant prognostic factors. No influence in disease-free survival was found for sex, race, primary site, urinary vanillylmandelic acid level, white cell count and platelet count. Overall 2-year disease-free survival was achieved in 27 (39%) patients. Four patients underwent bone marrow transplant, three of whom achieved 2-year disease-free survival. The results suggest that age, initial stage and hemoglobin level are significant prognostic factors based on univariate analysis. In addition, more Malaysian children presented with adrenal primary site and advanced disease compared to previous reported studies.

Localization of isoprenylated antigen of hepatitis delta virus by anti-farnesyl antibodies

Hepatitis delta virus (HDV) is a subviral pathogen that requires pre-existing or concurrent infection with hepatitis B virus (HBV). HDV expresses two forms of a single protein, the delta antigen (HDAg), which are identical except for an additional 19 residues at the C terminus of the large form. Within this C-terminal extension a cysteine residue is isoprenylated; this isoprenylation is critical for interaction with HBV envelope proteins to enable virus assembly and release into the medium. Therefore, large HDAg must be recruited to an extracellular compartment. However, immuno-staining with HDAg-specific antibodies has localized the large antigen mainly to the nucleus and supports the notion that large HDAg suppresses virus replication in the nucleus. Since isoprenylation would increase the hydrophobicity of the protein and may favour transport towards specific membranes, the question remains whether the large HDAg detected in the nucleus carries an isoprenyl group. To address this issue, antibodies against the farnesyl modification were generated to allow direct visualization of the antigen by immunofluorescence microscopy. The anti-farnesyl antibodies specifically stained large HDAg expressed in Huh-7 cells, and the signal was largely restricted to the nucleus; the staining pattern could be superimposed on those of cells stained for large HDAg. The large HDAg translocated into the nucleus was therefore isoprenylated. In addition, antibodies specific for the farnesyl modification should be applicable to the study of other similarly isoprenylated proteins.

Paralytic toxins in Taiwanese starfish Astropecten scoparius

Paralytic toxicity was seasonally detected in every 10 specimens of the starfish Astropecten scoparius from Pingtung in Taiwan from December 1995 to November 1996. The highest toxicity and the average toxicity of total specimens, expressed as tetrodotoxin (TTX), were 5,938 and 1,679 mouse unit (MU), respectively. The highest value of monthly average toxicity in viscera and other parts were 354 and 247 MU/g, respectively. The toxin was partially purified by YM-2 membrane ultrafiltration and Bio-Gel P-2 column chromatography. HPLC and GC-MS analyses showed that the starfish toxin was mainly composed of tetrodotoxin (88%), along with minor gonyautoxin 2-3 and saxitoxin (12%).

Distal renal tubular acidosis and hereditary elliptocytosis in a single family

Distal renal tubular acidosis (RTA) and hereditary elliptocytosis (HE) are apparently distinct, genetic conditions. We report a family with 3 children having both hereditary elliptocytosis and distal renal tubular acidosis. The simultaneous occurrence of these two conditions in three siblings could be due to covariations in the same family, although a possible contiguous gene syndrome for distal RTA and HE cannot be excluded. This report emphasises the importance of excluding a renal tubular defect in any child who presents with elliptocytosis and failure to thrive.

Non-familial haemophagocytic lymphohistiocytosis in children

Haemophagocytic Lymphohistiocytosis (HLH) is a rare clinical illness with a high mortality. There are reported effective treatment and a favourable outcome if diagnosed early. Five cases of childhood non-familial HLH seen over a 3 year period in our hospital are presented. The diagnosis was not suspected in the referring hospitals even after a bone marrow biopsy examination in two cases. Delay in referral was between 2 weeks to 2 months. A viral trigger was detected in only two cases. There were two deaths. Cause of death in both cases were cytomegalovirus pneumonitis and disseminated intravascular coagulopathy. Respond to treatment was better if started earlier. One case spontaneously resolved. Earlier diagnosis will lead to prompt treatment and a better outcome.

Second malignant neoplasms: an increasingly recognized complication of childhood cancer

Second malignant neoplasms (SMN) are an increasingly recognized late complication seen in childhood cancer survivors. A total of 3 cases of SMN have been found in the Department of Paediatrics, University Hospital Kuala Lumpur after a 15-year experience of treating childhood malignancies. Two cases are described here. The first developed abdominal non-Hodgkin's lymphoma 3 years after undergoing an allogeneic bone marrow transplant for second relapse of acute lymphoblastic leukaemia, while the second child developed myeloid leukaemia two years after completing treatment for acute lymphoblastic leukaemia. Progress in the management of childhood cancer in Malaysia and the availability of bone marrow transplantation facilities have increased the number of childhood cancer survivors; leading to increased incidence of SMN.

Intraabdominal desmoplastic small round cell tumour in an 11-year-old boy

A case of desmoplastic small round cell tumour (DSRCT) is presented. This aggressive and rare neoplasm predominantly affects males and is almost exclusively intraabdominal in location. It is unique in that neural, mesenchymal and epithelial markers are co-expressed. Despite multi-modal therapy, the prognosis is extremely poor. The present report details the clinical features and typical pathological findings of DSRCT in an 11-year-old boy, who succumbed to the disease 16 months after diagnosis despite multiple chemotherapeutic regimes.

Successful allogeneic bone marrow transplantation in severe chronic mucocutaneous candidiasis syndrome

We report the successful HLA-identical sibling bone marrow transplantation (BMT) of a 12-year-old boy with chronic mucocutaneous candidiasis (CMC) syndrome who also had Coomb's positive haemolytic anaemia and recurrent bronchopneumonia with resulting bronchiectasis. Conditioning was with busulfan and cyclophosphamide. Engraftment was slow but complete. Selective red cell haemopoietic failure was encountered soon after transplantation but resolved spontaneously. The patient remains alive 3 years after transplantation and now has normal immune, haemopoeitic and pulmonary functions. No manifestation of CMC has been evident since transplantation.

"Tubules-Within-a-Tubule" Hierarchical Order of Mesoporous Molecular Sieves in MCM-41

The recently discovered mesoporous aluminosilicate MCM-41 consists of hexagonal arrays of nanometer-sized cylindrical pores. It is shown that this material can be synthesized by cooperative condensation of silicate and cylindrical cationic micelles. Careful control of the surfactant-water content and the rate of condensation of silica at high alkalinity resulted in hollow tubules 0.3 to 3 micrometers in diameter. The wall of the tubules consisted of coaxial cylindrical pores, nanometers in size, that are characteristic of those of MCM-41. The formation of this higher order structure may take place through a liquid crystal phase transformation mechanism involving an anisotropic membrane-to-tubule phase change. The hierarchical organization of this "tubules-within-a-tubule" particle texture is similar to that of the frustules of marine diatoms.

Two brothers in a Malaysian family with X-linked lymphoproliferative disease--a case report

We report the occurrence of X-linked lymphoproliferative disease (XLP) in two brothers in a Malaysian family. In this disorder, a primary Epstein-Barr virus (EBV) infection is followed by an abnormal proliferation of transformed B-cells that cannot be controlled by suppressor T-cells, leading to the development of deranged immune function. This results in fatal infectious mononucleosis, acquired hypogammaglobulinaemia, virus-infected haemophagocytic syndrome and non-Hodgkin's lymphoma. The diagnosis should be considered when there is a family history of any male having a fulminant course of infectious mononucleosis, an otherwise benign disease. Early diagnosis is important as bone marrow transplantation is the only curative option in this disorder.

Concordant childhood acute lymphoblastic leukemia in monozygotic twins

Two 4-year-old monozygotic Chinese, female twins developed concordant childhood acute lymphoblastic leukemia (ALL) within an interval of about 2 weeks. Based on morphology and cytochemistry findings of the bone marrow blast cells, a diagnosis of ALL, L1 was made. Immunophenotyping showed the blast cells of both twins expressed similar antigens, i.e. HLA-DR, CD10, CD13, CD19, CD22 and CD34. Identical blood group, same HLA (human leucocyte antigen) genotype, sex and similar appearance suggest that the twins are monozygotic. Since the bone marrow leukemic cells of both twins were identical in morphology and expressed the same antigens with almost similar percentages of positivity, it is likely that the blast cells were derived from the same single clone. Based on the single clone hypothesis, the leukemogenic event must have arisen in utero in one twin and the cells from the abnormal clone then spread to the other twin via shared placental anastomoses.

Bone marrow transplantation in Malaysia

The sole BMT centre in Malaysia caters only for children. Since 1987, 89 transplants have been performed using reverse barrier nursing techniques. The overall survival rate is 73% with the majority of survivors leading normal lives. The early and late infection rates of 46% and 13%, respectively, are comparable to those of other centres. Although the early septicaemia rate is 36% the immediate mortality rate is < 10%. GVHD is less frequent and severe and the interstitial pneumonitis rate lower than that in the West. The average cost of US $8000 per transplant is much lower than the cost of a transplant performed overseas. Thus we believe that our paediatric BMT programme is simple and cost-effective.

Changing prognosis of childhood cancer--an overview

Significant advances in diagnosis and management have cured the majority of children with cancer. In the leukaemias, the commonest childhood malignancy, intensive induction-consolidation is important to ensure a lasting cure in about 65-80% and to eliminate the traditionally bad prognostic risk factors associated with less intensive treatment. Bone marrow transplantation (BMT) has a curative role in the minority who relapse particularly while on treatment. With few exceptions, most paediatric solid tumours are curable. Although the multimodal approach is responsible for the progress made, chemotherapy has emerged to play a dominant role. It has, in several tumours, obviated or reduced the need for radiotherapy and/or surgery. In Wilms' tumour and Hodgkin's disease, refinement of treatment is now in progress to reduce therapy-related morbidity while not sacrificing efficacy.