Gaucher's disease;thirty-two years experience at Siriraj Hospital

Gaucher's disease, a lysosomal disorder, is not a common disease in Thailand. During the period 1966-1998 we saw 20 patients with Gaucher's disease at the Department of Pediatrics. Siriraj Hospital. The patients came from different regions of the country but mostly from the central part of Thailand. There were 8 males and 12 females from 13 families of Thai, Thai-Chinese, Thai-Laos and Chinese-Chinese in origin. A history of consanguinity was present in 2 families. The age of onset was 2 months-4 years and the age when they were diagnosed was 4 months-15 years. The most common clinical features included splenomegaly, hepatomegaly, growth retardation, pallor, bleeding disorders and neurological abnormalities. The diagnosis was made by the clinical manifestations, hematologic complications and demonstration of Gaucher cells in the bone marrow and/or other tissues. In one family, the diagnosis was confirmed by evaluation of glucocerebrosidase activities in skin fibroblasts. The management of these patients was symptomatic ie packed red cell and platelet transfusion, splenectomy and other supportive measures. Most patients died of bleeding or infection at an early age.

Linear growth in homozygous beta-thalassemia and beta-thalassemia/hemoglobin E patients under different treatment regimens

The effects on linear growth and development among thalassemic patients under different treatment regimens were compared. Twelve homozygous beta-thalassemia (homozygous beta-thal) and 36 beta-thalassemia/Hb E (beta-thal/Hb E) were studied longitudinally between 1977 and 1998. Eighteen cases (10 homozygous beta-thal and 8 beta-thal/Hb E) received hypertransfusion with iron chelation by desferrioxamine. Another 30 cases (2 homozygous beta-thal and 28 beta-thal/Hb E) were given a low transfusion (depending on their clinical requirement). Their heights were measured serially and are presented as a standard deviation score (SDS). There was no significant difference in initial basic hematological data and ferritin levels between either group. However, the hypertransfused group, seemed to be clinically more severely affected than the other group as evidenced by early age at initial transfusion, the early onset of anemia and diagnosis and also their large acquired iron load after a period of transfusion. The average height SDS of the hypertransfused patients was within the 50th percentile +/- 1 SD during the first decade of life in both sexes and both genotypes. Whereas, in patients who were transfused infrequently, the SDS was always below the -1 SD and decreased gradually. In severe beta-thal/Hb E cases, their growth SDS showed no difference from those with homozygous beta-thal. Normal linear growth in those with homozygous beta thal and severe beta-thal/Hb E was only seen in the group that underwent hypertransfusion and this regimen contributed to normal growth during the first ten years of life. However, adequate iron chelation and hormonal treatment in these patients were also required in order to achieve normal adult height.

Successful prophylaxis of intracranial hemorrhage in infants with severe congenital factor VII deficiency

During the period 1984-1992, 2 severe cases (1 male, 1 female) of congenital F VII deficiency with intracranial hemorrhage (ICH) were referred to the Department of Pediatrics, Siriraj Hospital Bangkok, Thailand at the ages of 1 and 3 months old. They both responded very well to fresh frozen plasma (FFP) transfusion therapy. Subsequently, both had repeated episodes of ICH (repeated ICH) 5 and 6 times, despite the 10-14 days of replacement therapy for each episode and eventually died at the ages of 11 and 13 months. Since September 1996, another 2 severe cases (2 females) of congenital F VII deficiency who had ICH within their first month of life were referred to us. In order to prevent repeated ICH, we started a prophylactic regime after the second episode of ICH, by giving FFP 10 ml/kg twice a week. The average duration of follow up was 21 months (at 8 and 34 months). All of them (aged 14, and 38 months old) are doing well at this time and free from repeated ICH. From this observation, if there is FFP available, this regime is an effective way to prevent repeated ICH in infants with severe congenital Factor VII deficiency.

Successful bone marrow transplantation in a child with red blood cell pyruvate kinase deficiency

We report the first successful use of BMT for the treatment of RBC pyruvate kinase (PK) deficiency in a boy who developed neonatal jaundice and severe transfusion-dependent hemolytic anemia a few months after birth. He received a BMT at the age of 5 from an HLA-identical sister who has normal PK activity after conditioning with busulfan and cyclophosphamide. The post-transplant course was uneventful. At present, 3 years after transplant, he is 8 years old and has a normal hemoglobin level and normal RBC PK activity without evidence of hemolysis. DNA analysis has confirmed full engraftment.

Compound heterozygosity for one novel and one recurrent mutation in a Thai patient with severe protein S deficiency

Homozygous or compound heterozygous protein S (PS) deficiency is a very rare disorder in the anticoagulant system, that can lead to life-threatening thrombotic complications shortly after birth. This report describes the results of the genetic analysis of the PROS 1 genes in a Thai girl patient. She was reported in 1990 as the first case with homozygous PS deficiency and neonatal purpura fulminans. In the present report, we identified the mutations in this patient by direct sequencing of PCR products representing all 15 exons of the PROS 1 gene and their flanking intronic regions. The patient turned out to be compound heterozygous for two null mutations. One allele contained a novel sequence variation, an A-insertion in an A5-tract covering codon 146 and 147, that results in a frameshift and a stop codon (TAA) at position 155. The other allele contained a nonsense mutation in exon 12 by a transition at codon 410 CGA (Arg) to TGA (stop). Cosegregation of PS deficiency with these two genetic defects was observed in her family.

Bone marrow, peripheral blood and cord blood stem cell transplantation in children: ten years' experience at Siriraj Hospital

Stem cell transplantations were performed in 69 children at Siriraj Hospital over a ten year period. The source of stem cells was bone marrow (60), peripheral blood (3), or cord blood (6). The diseases treated included 35 thalassemias, 11 Burkitt's lymphoma, five non-Hodgkin's lymphoma, five aplastic anemia, eight acute leukemia, and one each of neuroblastoma, severe combined immunodeficiency, Wiskott-Aldrich syndrome, myelodysplastic syndrome, and pyruvate kinase deficiency. The success rate of stem cell transplantation in Thai children varied according to the underlying diseases of the patients, ranging from 50% in acute leukemia to 100% in aplastic anemia. The outcome of stem cell transplantation in 35 thalassemic children revealed 23 (79.4%) were cured, whereas three (10.3%) remain alive with disease and the other three (10.3%) died. The incidence of graft-versus-host disease was low hen compared with that of Western countries. It is concluded that bone marrow, peripheral blood and cord blood stem cell transplantation will be the treatment of choice and will be widely used in the future to cure many hematologic and malignant disorders in children.

Malignant lymphoma in Thailand: changes in the frequency of malignant lymphoma determined from a histopathologic and immunophenotypic analysis of 425 cases at Siriraj Hospital

BACKGROUND

Analysis of malignant lymphoma in a single institution at different periods of time can determine the changing status of the disease in the region.

METHODS

To compare with the large series of 1095 lymphoma cases reported between 1957-1971 at Siriraj Hospital, the largest hospital in Thailand, a similar study was performed through histopathologic evaluation of 425 lymphoma cases diagnosed consecutively at the same institution between August 1993 and October 1995. Phenotypic analysis was performed by paraffin section-immunoperoxidase studies.

RESULTS

A striking increase in lymphoma cases was noted from 73 cases/year in the first series to 189 cases/year in the second series (an increase of 158.9%). Lymphoma occurred in all age groups, with a peak incidence at the seventh decade of life. The male to female ratio decreased from 2:1 in 1957-1971 to 1.3:1 in the more recent series. The incidence of Hodgkin's disease (HD) was found to have decreased from 28.9% to 8.5%. There were 36 cases (8.5%) of HD and 389 cases (91.5%) of non-Hodgkin's lymphoma (NHL) reported in the second series. The subtypes of HD included 16 cases of mixed cellularity, 13 cases of nodular sclerosis, 6 cases of lymphocyte depletion, and 1 case of lymphocyte predominance. According to the Working Formulation, the 389 NHL cases included low grade (14.1%), intermediate grade (57.3%), high grade (11.3%), and miscellaneous groups (17.2%). They were classified as small lymphocytic (9.5%), follicular (11.1%), diffuse (50.9%), immunoblastic (4.1%), small noncleaved (4.4%), lymphoblastic (2.8%), anaplastic large cell (9.0%), mycosis fungoides (1.8%), hairy cell leukemia (0.3%), true histiocytic (0.5%), and extramedullary plasmacytoma (1.0%). The immunophenotypes of the 359 NHL cases available for paraffin section-immunoperoxidase studies were B-cell (71.0%), T-cell (24.5%), histiocyte (0.6%), and undetermined phenotypes (3.9%).

CONCLUSIONS

The incidence of malignant lymphoma is increasing in Thailand, with a high frequency of intermediate to high grade NHL of B-cell phenotype reported.

Pyruvate kinase deficiency in an alpha-thalassemia family: first case report in Thailand

In Thailand, the most common cause of chronic hemolytic anemia is thalassemia hemoglobinopathy. We report here a 10-year-old girl with pyruvate kinase (PK) deficiency who was initially diagnosed to have Hb H disease, like her sister. The patient had a history of neonatal jaundice which required blood exchange transfusion twice and phototherapy. She became anemic and regular blood transfusion was required since the age of 2 1/2 months. She was very anemic compared to her sister and was transfusion dependent. Besides, she never had red cell inclusion bodies, thus re-evaluation was performed. The diagnosis of red cell pyruvate kinase deficiency and the exclusion of Hb H disease was achieved after cessation of blood transfusion for 3 months. The family study also confirmed the diagnosis. The patient is now on high transfusion and iron chelation. She is doing well with mild splenomegaly.

Collection of cord blood stem cells for transplantation in thalassemic patients

Thalassemia is widely distributed throughout the world and is one of the major public health problems. The use of bone marrow transplantation, the only curative therapy for thalassemia, is limited because less than 30% of the patients have unaffected and HLA-identical siblings as donors. Cord blood stem cells, an alternative source of stem cells for transplantation, have been successfully transplanted into patients with several diseases after myeloablative therapy. Twenty cord blood samples from unaffected neonates whose siblings had severe thalassemia were collected. The median volume was 80 ml. The median number of cells and colony forming units-granulocyte-macrophage in cord blood was 9.2 x 10(8) and 3.4 x 10(5), respectively. Four of 20 cord blood samples had HLA-matched to the affected siblings. One patient underwent cord blood transplantation with success; one patient is waiting for transplantation.

Immunogenicity and efficacy of a recombinant DNA hepatitis B vaccine, GenHevac B Pasteur in high risk neonates, school children and healthy adults

The immunogenicity and the protective efficacy of a recombinant DNA hepatitis B vaccine, GenHevac B Pasteur with or without passive immunization with hepatitis B immunoglobulin (HBIG) in high risk neonates born from HBsAg and HBeAg positive mothers was evaluated. Twenty-six neonates (group A) received HBIG 100 IU intramuscularly at birth plus GenHevac B Pasteur 20 micrograms at birth, 1, 2 and 12 months of age while another 23 neonates (group B) received only GenHevac B Pasteur vaccine. Forty high risk newborns who received no immunization served as control group. It was found that at months 4, 12, 13 and 24 the seroconversion rate in both group A and B were very high in the range of 95-100% with the GMT ranging from 10-160,000 mlU/ml. In the control group of infants, 85% had HBsAg positive at one year of age but it was only 3.8% and 8.7% in vaccinated groups A and B, respectively. The protective efficacy in neonates group A and B were 95.5% and 89.8% at one year, respectively, with no statistically significant difference. In 46 normal school children (group C) and 48 healthy adults (group D) who received the same dose of GenHevac B Pasteur the seroconversion rates at month 4 after receiving 3 doses of vaccination were 97.8% and 83.3% in group C and group D, respectively. At month 12, the seroconversion rate in group C rose to 100% and was significantly higher than the 89.6% of group D.(ABSTRACT TRUNCATED AT 250 WORDS)

Long term efficacy of hepatitis B immunoprophylaxis in neonates at risk: using different vaccine and schedule

Passive and active immunization for the prevention of hepatitis B virus (HBV) transmission in neonates born to HBeAg positive carrier mothers was studied using different kinds and dosages of combined hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine. The long term efficacy of these various immunoprophylaxis programmes was evaluated up to 3 years of age. Eight groups of neonates, 20 in each group, received HBIG either the usual dose of 100 IU intramuscularly or intravenously or increased dose to 200 IU, combined with different kinds of hepatitis B vaccine either in full dose or half dose given in different schedules of 0, 1, 2 or 0, 1, 6 months, in some groups also received a booster dose at 12 months. After follow-up for 3 years, there were no statistical significant differences of the results between these 8 different immunoprophylaxis programmes, either in the rate of seroconversion or the protective efficacy as well as the antibody response (anti-HBs titer). The seroconversion rates after 3 years of age in all 8 groups were in the range of 63.6 to 92.9 per cent. The protective efficacy rates at 3 years of age were in the range of 69.7 to 100 per cent.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunogenicity and protective efficacy of low dose recombinant DNA hepatitis B vaccine in normal and high-risk neonates

A low dose of recombinant DNA hepatitis B vaccine (HB-VAX II, MSD) was tested for efficacy in the prevention of perinatal hepatitis B virus (HBV) transmission in normal and high-risk neonates born from HBsAg carrier mothers. A dose of 2.5 micrograms recombinant vaccine was injected intramuscularly at 0, 1, 2 and 12 months of age to 30 newborns from HBsAg negative mother (group I), 30 from HBeAg negative/HBsAg carrier mother (group II) and 30 from HBeAg positive/HBsAg carrier mother (group III). The incidence of persistent HBsAg carrier infants at 13 months of age was 0, 0, and 30.4 percent in groups I, II and III, respectively. The protective efficacy in high risk infants in group III was 65.7 percent. The seroconversion at month 4, after the third dose of vaccination was 96.3, 95.7 and 100 percent in group I, group II and group III, respectively. After a booster dose of vaccination at 12 months of age, the seroconversion rose to 100 percent at month 13 in all three groups. The geometric mean titer (GMT) of anti-HBs antibody at 13 months of age were 2,092, 1,657 and 1,938 mIU/ml in group I, group II and group III, respectively. It is concluded that the low dose (2.5 micrograms) recombinant hepatitis B vaccine using alone is effective in prevention of perinatal HBV transmission in low risk infants (groups I and II), but it is less effective in high risk infants (group III).(ABSTRACT TRUNCATED AT 250 WORDS)

Sinus histiocytosis with massive lymphadenopathy: the first three cases reported in Thailand

Three cases of sinus histiocytosis with massive lymphadenopathy are reported in Thai children and is probably a first report in Thailand. They were clinically characterized by bilateral massive cervical lymphadenopathy. Other lymph node groups were also involved but no extranodal manifestations could be detected. Leukocytosis with neutrophilia, hypergammaglobulinemia and polyclonal gammopathy were common features. The characteristic histopathologic findings in the involved lymph nodes included pericapsular fibrosis, markedly dilatation of subcapsular and medullary sinuses which were filled with numerous histiocytes showing active phagocytosis of lymphocytes and lymphoplasmacytoid proliferation in paracortical strands and medullary cord. The disease characteristically has a benign protracted clinical course, and does not respond to either irradiation or chemotherapy. The etiology and pathogenesis of this disorder are unknown. The possible pathologic mechanisms include an abnormal response to a specific infectious process and an immune deficiency status.

Massive chemotherapy and autologous bone marrow transplantation in Burkitt's lymphoma: the first two patients successfully treated in Thailand

Massive chemotherapy and autologous bone marrow transplantation (ABMT) have been successfully used for the treatment of Burkitt's lymphoma. We report our first success with such treatment in two children with Burkitt's lymphoma in Thailand. Both patients had massive abdominal tumors with ascites and minimal bone marrow metastasis at the first presentation. They received induction chemotherapy and intensive treatment including central nervous system prophylaxis with cranial irradiation and intrathecal methotrexate until being in complete remission before starting massive chemotherapy, comprising the combination of BCNU, cytosine arabinoside, cyclophosphamide and 6-thioguanine followed by ABMT. Both patients recovered completely following intensive supportive treatments post ABMT and are still good health without evidence of the disease for 18 and 8 months after transplantation respectively. The role of massive chemotherapy and ABMT for the treatment of non-Hodgkin's lymphoma especially Burkitt's lymphoma was discussed.

Hormonal and growth status in long term survivors of acute lymphoblastic leukemia (ALL) in children

Nineteen children and adolescents in long-term complete remission from acute lymphoblastic leukemia (ALL) were studied for hormonal and growth status after cessation of therapy. Cranial irradiation of 600-2,400 cGy was given for C.N.S. prophylaxis in 18 out of 19 patients, and additional irradiation of 2,000 cGy was given to both testes of a prepubertal boy because of testicular infiltration. The time ranges after cranial irradiation and cessation of therapy at the time of study were 61-137 months and 5-127 months respectively. Thyroid hormone, cortisol and peak cortisol response after ACTH stimulation were normal in every tested children. Basal serum gonadotropin and sex steroid values were appropriate in the majority of patients. A child who received testicular irradiation, had elevated levels of gonadotropins. Glucagon stimulation test (GST) and/or L-Dopa propranolol test (DP test) were used to study growth hormone (GH) response. None had peak GH value less than 7 ng/ml. Ten patients had peak GH values of over 15 ng/ml. Nine female patients had normal puberty and regular menstruation. Eight out of ten male children also had normal puberty. All except two male patients had normal linear growth within 2 standard deviations of the mean. The mean attained final height of 11 children was not significantly different when compared to the mean predicted heights obtained from Bayley-Pinneau and Tanner methods. Excessive weight gain during and after cessation of chemotherapy was observed in the majority of children. Continuing long-term review of these children is essential.(ABSTRACT TRUNCATED AT 250 WORDS)

Subcutaneous mucormycosis caused by Saksenaea vasiformis in a thalassaemic child: first case report in Thailand

A first case of subcutaneous infection caused by Saksenaea vasiformis in an 11-year-old Thai thalassaemic boy was described. The specific diagnosis of infection was attained from microscopic demonstration of the causal agent as well as the isolation of the fungus. The patient was successfully treated by debridement of the lesion and parenteral amphotericin B. The predisposing factors, source of infection and regimen for treatment are discussed.

Molecular basis of beta-thalassemia in Thailand: analysis of beta-thalassemia mutations using the polymerase chain reaction

beta-Thalassemia mutations in 71 chromosomes of Thai patients from the northeast, the middle and the south of the country were investigated using dot blot hybridization of PCR (polymerase chain reaction)-amplified DNA with allele-specific oligonucleotide probes. Eight different known molecular defects were detected, at different frequencies. There was an amber mutation in codon 17, a C-T transversion at position 654 of IVS-2, a frameshift mutation between codons 71 and 72, an A-G transition at nucleotide -28 within the TATA box (known as Chinese mutations), a G-T transversion at position 1 of IVS-1 (an Indian mutation), a 4 bp deletion in codons 41/42 and a G-C transversion at position 5 of IVS-1 (described as both Chinese and Indian mutations) and a Thai original mutation, an ochre mutation in codon 35. Analysis of the three unknown alleles by DNA sequencing of the cloned DNA fragment amplified by PCR revealed an A-G substitution at the second position of the codon for amino acid 19 (AAC-AGC). The analytic approach used in the present study and the characteristic distribution of mutations in each region of Thailand will prove useful for setting up a prenatal diagnosis program.

Hepatitis B immunization in high risk neonates born from HBsAg positive mothers: comparison between plasma derived and recombinant DNA vaccine

A half dose recombinant hepatitis B vaccine (HBVax II, MSD, 5 micrograms) was investigated for efficacy in the prevention of perinatal hepatitis B virus (HBV) transmission in high risk neonates born from e-antigen positive HBsAg carrier mothers as compared to the half-standard dose regimen of plasma derived hepatitis B vaccine (HBVax, MSD, 10 micrograms). Forty infants born to carrier mothers were given hepatitis B immune globulin (HBIG) 100 IU intramuscularly immediately after birth, combined with either the recombinant or plasma derived hepatitis B vaccine. The infants were randomly divided into two groups of 20 infants each. The plasma derived vaccine (10 micrograms) was given to group I, while infants in group II received the recombinant vaccine (5 micrograms) at birth, 1 and 6 months of age. There were no statistically significant differences in the efficacy and the seroconversion rate of these two combined prophylaxis regimens. The protective efficacy rate of both kinds of HBV vaccine was found to be 94.6 and 89.2 percent in group I and group II respectively. At twelve months of age, the anti-HBs seroconversion rates were 95.0 percent in group I and 84.2 percent in group II. However, the geometric mean titres in group I (179.55 mIU/ml) was significantly higher than those in group II (42.2 mIU/ml) but the anti-HBs titre was still above protective level (10 mIU/ml) in most of the infants.(ABSTRACT TRUNCATED AT 250 WORDS)

Kinetics of lymphocyte subpopulations in dengue hemorrhagic fever/dengue shock syndrome

A kinetic study of lymphocyte subpopulations was performed in 61 dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS) patients aged 8 months to 12 years and in 59 age-matched normal controls. There were 36 patients in grade 2 and 25 patients in grade 3 of the disease severity. The studies were performed on febrile stage, the day of subsidence of fever or shock stage, 3 subsequent days after subsidence of fever or shock, and once on the recovery stage (approximately 14-18 days after subsidence of fever or shock). The study revealed that the absolute total lymphocytes, CD3+, CD4+, CD8+ and HNK-1+ cells were decreased on febrile stage and their lowest values were noted on the first day of subsidence of fever or shock, while B1+ cells were in the normal range. Thereafter, all lymphocyte subpopulations were increased. The total lymphocytes, B1+ and CD8+ cells were rapidly increased and were above normal value on day 2 after subsidence of fever or shock (early convalescence), then gradually declined to the normal range. In contrast, CD3+, CD4+ and HNK-1+ cells were increased gradually and reached their normal values on day 2 after subsidence of fever or shock. The T4:T8 ratio began to reverse on the day of subsidence of fever or shock, reached its peak on day 2 after shock and returned to normal ratio rapidly thereafter. Thus, the absolute lymphopenia on the day of shock was due to the decrement or T cells (both CD4+ and CD8+ cells) and HNK-1+ cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Natural killer cells in dengue hemorrhagic fever/dengue shock syndrome

Natural killer (NK) cell activity against K-562 target cells and HNK-1+ cell levels were serially determined in peripheral blood of 62 Thai children with dengue hemorrhagic fever/dengue shock syndrome aged 4-12 years and 59 age-matched normal controls. The studies were performed on febrile stage, 1st and 2nd day of subsidence of fever (shock stage), 3rd and 4th day of subsidence of fever (early convalescent stage) and once again on the late convalescent stage (approximately 14-18 days after subsidence of fever). The study revealed that during the course of disease the NK cell activity was not changed significantly from the normal controls. In contrast, the levels of HNK-1+ cells, which exhibited almost all NK and killer cell functional activities, were significantly decreased in the febrile and the shock stages and were normal in the early and late convalescent stages. The NK cell activity, on the per-cell basis, was significantly increased in the early disease stage when compared to that of the later period of the disease and of the normal controls. The study also revealed that patients with grade III of disease severity exhibited significantly more NK cell functional activities per cell than grade II on febrile stage and the first day of shock. These results suggest that natural killer cells were active in defense against dengue viral infection and might play some role in the pathogenesis of dengue hemorrhagic fever/dengue shock syndrome. Their functions might also determine the severity of the disease.

Studies on the pathogenesis of aplastic anemia in Thailand: evidence of immune-mediated mechanism

The pathogenesis of aplastic anemia in Thailand was studied by using in vitro progenitor cells culture. In 37 patients who had active disease, the numbers of colonies derived from erythroid and granulocyte-macrophage progenitor cells (BFU-E and CFU-GM) were markedly decreased both in the blood and bone marrow as compared to normal controls. Co-culture of patients' cells with normal blood cells was performed in order to verify an immunologically mediated mechanism. In 8 of 26 patients, there were very low numbers of colonies both BFU-E and CFU-GM in the blood and bone marrow with significant suppression of colony formation in co-culture. Suppressor cells may have caused the aplasia in these patients. The rest had low colony formation and no suppression in co-culture. These patients may have absent or defective stem cells. None had normal colony formation. Therefore, aplastic anemia in Thailand may result mostly from defects involving the stem cells. Only some patients had cell mediated suppression of hematopoiesis as detected by co-culture.

Efficacy of hepatitis B virus (HBV) vaccine in long term prevention of HBV infection

Efficacy of HBV vaccine in long term prevention of HBV infection was evaluated at 3 years after vaccination in 38 children and 61 adults. All vaccinees were negative for all HBV markers (HBsAg, anti-HBs and anti-HBc) before vaccination. Vaccines (Hevac B) were given for 3 doses, one month apart, to 38 children aged 1 month - 14 years and 61 adults aged 15-45 years. After 3 years of vaccination, blood specimens were collected for the determination of HBsAg, anti-HBs and anti-HBc. The results revealed that no HBsAg antigenemia was found in all 99 vaccinees. Anti-HBs could not be detected in 4 children and 11 adults and this occurred only in the group of subjects who had initial anti-HBs less than 100 mlU/ml at 2 months after the last dose of vaccination. At three years after the first course of vaccination, 89.4 percent of children and 83.4 percent of adults still have anti-HBs above protective level (more than 10 mlU/ml) with geometric mean titers of 101 and 35 mlU/ml in children and in adult groups, respectively. The anti-HBc was detected in 2 out of 38 children and 10 out of 61 adults, but none of them became chronic hepatitis B carriers or developed clinical disease. It is recommended that everyone with anti-HBs values below 100 mlU/ml two months after the last dose of vaccine should be revaccinated with a booster dose within 6 months. Those with anti-HBs levels higher than 100 mlU/ml, should be checked up at 3 years; if the anti-HBs is less than 10 mlU/ml, they should be revaccinated.

Active pre-exposure immunisation against hepatitis B virus: immunogenicity of hepatitis B vaccine in healthy Thai adults and children

The immunogenicity of plasma derived hepatitis B vaccine (Hevac B) was studied for active pre-exposure immunisation in 176 healthy volunteer adults and 162 randomised children who had no hepatitis B virus markers. All subjects received three injections of 5 micrograms of hepatitis B vaccine intramuscularly at one month intervals. Seroconversion at 2 months after the third dose of vaccine was 96.30 percent in the children and 92.00 percent in the adults with mean anti-HBs titres of 800 mlU/ml and 353 mlU/ml respectively. The difference of anti-HBs levels between these two groups was statistically significant (p less than 0.05). Female adults had exhibited higher immune response to HB vaccine than male adults but there was no seroconversion difference between boys and girls. There were no serious local or systemic side effects of hepatitis B vaccination. It was concluded that active immunisation with plasma derived hepatitis B vaccine in non-immune children and adults is highly effective without any serious side effects or complications. The prevention of horizontal transmission of hepatitis B virus should be done by vaccination in children since they have a much better immune response to hepatitis B vaccine than adults.

[Persistent HBsAg antigenemia in newborn infants following intrauterine HBV infection. Cause for the failure of the prevention of perinatal HBV transmission]

In areas with high carrier rates for hepatitis B the combination of hepatitis B immune globulin and hepatitis B vaccine prevent perinatal infection in 90-95% of the newborn infants. Since 1979 the failure of perinatal prevention of hepatitis B infection was observed in only two cases. Evidence of intrauterine infection is presented in these two cases.

Efficacy of hepatitis-B immunoglobulin and hepatitis-B vaccine in prevention of the HBsAg carrier state in newborn infants of mothers who are chronic carriers of HBsAg and HBeAg

Combined prophylaxis of perinatal transmission of hepatitis B virus (HBV) with hepatitis-B immunoglobulin (HBIG) and hepatitis-B vaccine was investigated in 40 infants born to HBeAg positive carrier mothers. The efficacy of two combined prophylaxis schedules was compared to 78 similar infants in the control group receiving no treatment, by following the HBV markers at regular intervals up to one year of age. In both schedules, the HBIG and HBV vaccine were given at birth, followed by HBV vaccine given at 30 days and 60 days (group I) or 180 days (group II) of age. The incidence of persistent HBsAg carrier in infants born to HBeAg positive carrier mothers was significantly reduced from 92.6 percent at one year of age in the control group to zero percent (group I) and 11.5 percent (group II) in the treated groups. There was no statistical significant difference in the efficacy of these two combined prophylaxis schedules. HBIG given at birth did not interfere with infant immune response to the hepatitis B vaccine. At twelve months of age, anti-HBs could be detected in 77.8 percent of infants in group I and 89.5 percent in group II with mean titre of 621.4 and 1148.0 in group I and group II respectively. It was concluded that combined prophylaxis with HBIG and hepatitis-B vaccine immediately after birth is the best method for prevention of HBV perinatal transmission from HBeAg positive carrier mothers to their infants.

Perinatal transmission of hepatitis B virus in Thailand

Perinatal transmission of hepatitis B virus (HBV) from asymptomatic HBsAg carrier mothers to their infants was studied in 78 mother-infant pairs by determination of HBsAg, HBeAg and anti-HBe both in the mothers and in their infants at regular intervals for those children up to the time when they reached at least one year of age. Twenty-five out of the 78 (32.1%) infants born to these mothers were HBsAg-positive 2-6 months after birth and they remained so throughout the observation period of at least one year or more. Perinatal HBV transmission occurred only in infants born to HBsAg carrier mothers who were HBeAg-positive (92.6%) but not in those born to HBsAg carrier mothers who had no detectable HBeAg. This study suggests that preventive measures against HBV transmission during the perinatal period should be taken only for infants born to HBsAg carrier mothers who are HBeAg-positive. In addition, the active immune response to HBV was studied in 75 non-HBsAg carrier infants born to HBsAg carrier mothers by determination of anti-HBs at one year of age or older. Forty-three of these infants were treated with HBIG at birth and 32 infants received no treatment. It was found that infants born to HBsAg carrier mothers who were HBeAg-positive had a better active immune response (84.2% positive for anti-HBs) than infants born to HBsAg carrier mothers who had no detectable HBeAg or anti-HBe (14.3% and 20.4% positive for anti-HBs respectively).

Susceptibility to varicella-zoster virus in Thai children and young adults

During 1982-1983, susceptibility to varicella-zoster virus (VZV) in 224 Thai subjects at high risk for varicella infection was studied. The immune adherence hemagglutination (IAHA) and VZ skin test were carried out to determine VZV immunity in immunocompromised children and young adults. The history of varicella and herpes zoster from each subject was recorded. The mean +/- SD age in children and young adults were 7.3 +/- 2.8 and 19.6 +/- 1.2. Negative IAHA test was found in 74.2% of 62 children and 35.2% of 162 young adults. The increase in immune individuals was demonstrated with advancing age. Response to VZ skin test showed positive results in 79 of 162 (48.8%) young adults. The seronegativity was related to the negative VZ skin test (p less than 0.001, X2 test). Regardless of antibody detection or VZ skin test, 47 of 162 (29%) young adults were susceptible. According to the positive history of varicella and of herpes zoster obtained from 95 young adults, 80% had developed varicella during 1 to 10 years of age and 8.8% had positive history of herpes zoster. The findings suggest that the IAHA and VZ skin test should be used together for assessing VZ immunity. Varicella vaccination is highly recommended for susceptible persons who may develop severe illness.

Detection of varicella-zoster antibody by immune adherence hemagglutination test

The immune adherence hemagglutination (IAHA) is a more sensitive and specific test for evaluation of humoral immunity to varicella-zoster virus (VZV) than a conventional complement fixation (CF) test. The equipment, reagents, procedure used in the IAHA are basically the same as those employed in the CF test. After VZ vaccination, seroconversions detected by IAHA test were significantly greater than those by CF test (P less than 0.01, chi 2 test). Moreover, the IAHA titers were higher about 4 times (G.M. 30.9 vs 8.2) and persisted longer than CF titers. Although the IAHA antigen is not a commercial product, the IAHA is sensitive and suitable assay for VZ antibody determination in routine serological laboratory.

Vaccination against hepatitis B virus infection in neonates

The efficacy of hepatitis B virus vaccine to prevent the vertical transmission of hepatitis B virus (HBV) in infants born to HBsAg carrier mothers was assessed in 20 mother-infant pairs. A dose of 10 micrograms of HBV vaccine was injected intramuscularly at 0, 30 and 180 days after birth to newborn infants. Neither local nor systemic reaction was observed after the administration of HBV vaccine. The incidence of persistent HBsAg carrier infants born from e-antigen positive HBsAg carrier mothers in HBV vaccine treated group was only 37.5% at one year of age as compared to 85.7% in the untreated control group. Anti-HBs developed in 88.2% of infants after the third dose of HBV vaccination with a mean anti-HBs titer of 1733.1 IU/l. It is concluded that HBV vaccine was effective and safe in reducing the rate of vertical transmission of HBV from the HBsAg carrier mothers to their infants. The vaccine was also immunogenic since almost 90% of the immunized infants were able to produce anti-HBs antibody in high titer after the third dose of vaccination.

Burkitt's lymphoma in Thai children: an analysis of 25 cases

Twenty five cases of Burkitt's lymphoma in Thai children were diagnosed at the Department of Pediatrics, Siriraj Hospital during the period of 13 years (January 1969 to April 1982). Males were more affected than females with the ratio of 1.7:1. The age ranged from 2 to 11 years with the median age of 4-5 years. The most common clinical manifestations were abdominal mass associated with nausea vomiting, abdominal pain, anorexia, weight loss and generalized lymphadenopathy which occurred in 50-60% of cases. Additional symptoms and signs included anemia, hepatosplenomegaly, edema and pleural effusion. Jaw tumor was found in only 37.5% of the patients. Definite diagnosis depended on the characteristic starry sky appearance of the lymph node biopsy or section of abdominal mass. In advance cases, the tumor cells could be discovered in bone marrow aspiration, ascitic fluid pleural fluid and cerebrospinal fluid. The typical blast cells were detected in the peripheral blood in 4 cases. Antibody to Epstein-Barr virus could be detected in almost all cases with high titers in some cases. Most patients responded very well to local irradiation and chemotherapy with prednisolone plus cyclophosphamide and vincristine or methotrexate. However, relapse occurred rapidly and 80% of the patients died within 3 months after diagnosis with the median survival of only 1 month. Five cases expired early before any specific treatment. The main causes of death were disease, sepsis, excessive bleeding and hyperkalemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Transient, acquired glucose-6-phosphate dehydrogenase deficiency in Thai children with typhoid fever

Seventy nine children with typhoid fever were studied, 45 were males and 34 were females. There were 9 out of 45 males patients (20%) who had definite G-6-PD deficiency of whom 3 had acute intravascular hemolysis. The rest of the patients had transient low enzyme activity during the first few weeks of their illness, with reticulocytopenia. Their G-6-PD activities rose up to normal level later in the course of the disease while the reticulocytes were also increased. This study demonstrated that even in normal G-6-PD subjects, typhoid fever can cause transient, acquired low G-6-PD level due to bone marrow suppression. It was suggested from this study that quantitative G-6-PD assay was more useful and sensitive than the screening method and that long term follow up is needed in the case that had unexplained low G-6-PD activity.