Croup syndrome in children: five-year experience

To investigate the etiology and clinical features of croup syndrome, clinical records of hospitalized children with a diagnosis of croup syndrome were reviewed from April 1990 to January 1996. There was a total of 132 children, aged between three months and seven years with a mean age of 21.3 +/- 16.8 months. A diagnosis of laryngotracheobronchitis was made in 123 (93.2 percent) children. Twenty-three pathogens were identified in twenty-two of them, including seven parainfluenza viruses, five respiratory syncytial viruses, four influenza A viruses, four Mycoplasma pneumoniae, and three adenoviruses. Bacterial tracheitis was confirmed by bronchoscopic examination in seven cases (5.3 percent). Cultures of the respiratory secretions yielded viridans streptococci in six and Staphylococcus aureus in one child. Two children (1.5 percent) had spasmodic croup. No case with epiglottitis was noted in the present study. A fever lasting for more than three days was noted in five (71 percent) children with bacterial tracheitis and thirty-five (28 percent) children with laryngotracheobronchitis (p = 0.048). Among children with laryngotracheobronchitis, an associated diagnosis of pneumonia, acute otitis media, or paranasal sinusitis was more frequently observed in those with fever > 3 days (40 percent) than those with a shorter duration of fever (17 percent, p = 0.013). In conclusion, a child with a longer duration of fever and more severe manifestations of airway obstruction probably has a bacterial cause of croup syndrome or a bacterial complication. Bacterial tracheitis is more common than epiglottitis in Taiwan.

Long term immune response of universal hepatitis B vaccination in infancy: a community-based study in Taiwan

OBJECTIVES

To evaluate the long term immunity provided by a universal hepatitis B vaccination program in infancy and the booster effect on school age children who had no protective antibody titers to hepatitis B surface antigen.

METHODS

We conducted a community-based seroepidemiologic study of 1337 healthy 7-year-old children in Taiwan one decade after the implementation of a mass hepatitis B vaccination program. A booster vaccination was suggested for noncarrier children who did not have protective titers of surface antibody. Serologic responses and infection rates were compared with those of the nonboostered children. In a nonselected group of 39 volunteer noncarrier vaccinees, quantitative serologic response was determined before, 1 month after a booster vaccination and 1 year later.

RESULTS

A total of 572 children (42.8%) had low concentrations of surface antibody, and 9 were hepatitis B surface antigen carriers (0.7%). Eighty-two percent of "nonprotected" vaccinees showed immunologic memory to a booster dose and developed protective antibody titers 1 month later; 60.6% maintained protective titers 1 year later. The frequency of new hepatitis B virus infection was similar for those who received a booster and those who did not as investigated by the core antibody seroconversion during 1-year follow-up. However, the risk was low, with annual incidences of <1% in both groups, and none became chronic carriers.

CONCLUSION

According to these data a universal vaccination program in infancy provides adequate protection against hepatitis B virus infection for school age children and a booster vaccination is not recommended.

Long-term response to hepatitis B vaccination and response to booster in children born to mothers with hepatitis B e antigen

Hepatitis B (HB) vaccine provides an uncertain duration of protection and the optimal timing of booster vaccine remains unclear. This study examined the immune response at 10 years of 118 children who had developed protective anti-HB surface (anti-HBs) levels after a primary series of HB immunizations in infancy. All of the children were born to hepatitis B e Antigen (HBeAg)-positive hepatitis B surface antigen (HBsAg) carrier mothers. HB markers in all subjects and cellular immune response in some were determined. A booster was given to all subjects after the collection of samples and another blood sample was collected 4 weeks later. The results showed that a total of 39 (33%) of the children were seronegative for anti-HBs. T-cell proliferative response to HBsAg was noted in 47% of children. On HBsAg stimulation, leukocyte samples from a significantly higher proportion of subjects produced cytokines (81% of T cells produced interleukin-2 [IL-2] and 100% produced IL-5). The booster dose of HB vaccine induced the production of a protective level of anti-HBs (>/=10 mIU/mL) in all subjects. Cellular immunity was augmented with a positive rate of 58%, 90%, and 100% for HBsAg-induced T-cell proliferation, IL-2 production, and IL-5 production, respectively. Although 14 (11.9%) of the subjects were HB core antibody positive at 10 years of age, no new HBsAg carrier was detected. The results of this study show that protection afforded by HB vaccination persisted to the age of 10 years in all vaccinees. Immunologic memory was detected in all subjects including those who had lost their anti-HBs seropositivity. These results suggest that no booster vaccination is needed before 10 years of age. The most sensitive marker of immunologic memory is IL-5 production of T cells. (HEPATOLOGY 1999;29:954-959.)

Minilaparoscopy to reduce complications from cannula insertion in patients with previous pelvic or abdominal surgery

STUDY OBJECTIVE

To evaluate the safety and efficacy of minilaparoscopy for visualization and adhesiolysis of intraabdominal adhesions for safe insertion of a primary umbilical cannula in patients who had previous pelvic or abdominal surgery.

DESIGN

Prospective, observational study (Canadian Task Force classification II-1).

SETTING

University-affiliated hospital.

PATIENTS

Twenty women who had previous pelvic or abdominal surgery, excluding tubal ligation and simple appendectomy.

INTERVENTION

Minilaparoscopy was carried for visualization and adhesiolysis at the entry site before insertion of an umbilical cannula.

MEASUREMENTS AND RESULTS

Eleven patients had Pfannenstiel scars and nine had vertical midline scars from previous surgeries (4 total abdominal hysterectomies, 13 adnexal surgery, 7 cesarean sections, 3 ectopic pregnancies, 1 ruptured appendix, 1 unknown bowel surgery). Thirteen women (65%) had had one previous surgery, five (25%) had had two, and two (10%) had had three. Nine patients (45%) had significant adhesions of omentum or intestine that required adhesiolysis. Mean operating time for minilaparoscopy was 5 minutes for 11 women who had no or minimal adhesions that did not interfere with safe insertion of the umbilical cannula and effective use of a 10-mm telescope, and 25 minutes in 9 patients who required adhesiolysis before insertion of the umbilical cannula because of dense adhesions of omentum or intestine at the entry site. No complications with minilaparoscopy occurred.

CONCLUSION

Minilaparoscopy can be performed safely and effectively to reduce serious vascular or visceral injury from insertion of primary cannula in patients who had previous pelvic and/or abdominal surgery. However, conclusions cannot be derived from this study due to the small number of subjects. Further study is necessary in a larger patient population to evaluate efficacy, safety, and advantages of minilaparoscopy over other techniques. (J Am Assoc Gynecol Laparosc 6(1):91-95, 1999)

An evaluation of the safety and immunogenicity of a five-component acellular pertussis, diphtheria, and tetanus toxoid vaccine (DTaP) when combined with a Haemophilus influenzae type b-tetanus toxoid conjugate vaccine (PRP-T) in Taiwanese infants

OBJECTIVE

Immunologic interference particular to the Haemophilus influenzae type b (Hib) response has been observed with previous acellular pertussis-Hib combination vaccines. To test this hypothesis a clinical trial to assess the safety and immunogenicity of a five-component (pertussis toxoid [PT], filamentous hemagglutinin [FHA], pertactin [PRN], and fimbriae 2 and 3 [FIM]), pertussis vaccine combined with diphtheria and tetanus toxoids (DTaP) when given simultaneously with a lyophilized Hib-tetanus toxoid conjugate vaccine (PRP-T) in infants at 2, 4, 6, and 18 months of age was conducted. The study compared two methods of administration: both vaccines combined in a single syringe and administered as a single injection, or both vaccines administered concurrently but at separate sites of injection.

METHODS

Healthy 2-month-old infants were enrolled at the National Taiwan University Hospital. DTaP, PRP-T, and oral poliomyelitis vaccine (OPV) were given at 2, 4, 6, and 18 months. Reaction information was collected by telephone 2 days after each vaccination. Serum was collected at 2, 6, 7, 18, and 19 months of age.

RESULTS

One hundred thirty-five healthy infants were enrolled in Taiwan, of which 127 (94%) completed the 18-month booster: 68 received the combined vaccine and 67 the separate vaccines. All vaccines were well tolerated. No differences in rates of local and systemic reactions were seen between the two methods of administration. No serious adverse events were reported. Serologic responses were comparable between the groups. Pertussis responses (enzyme-liked immunoabsorbant assay units [EU]/mL) at 7 months were, for combined versus separate, PT (131 vs 105), FHA (116 vs 116), PRN (100 vs 77), and FIM (922 vs 702). At 19 months, pertussis results were, for combined versus separate, PT (216 vs 182), FHA (203 vs 200), PRN (263 vs 197), and FIM (892 vs 732). Only the 7-month PT response in the combined group was significantly higher (combined 131 EU/mL vs separate 105 EU/mL). After the third dose (age 6 months), all subjects achieved serologic serum antibody levels indicative of protection against Hib, diphtheria, tetanus, and poliovirus types 1, 2, and 3. In fact, 96% of children had anti-PRP levels indicative of protection (>/=0.15 microgram/mL) against Hib after only two doses. At 7 months, anti-PRP geometric mean titer values were 11.8 micrograms/mL in the combined group compared with 13.0 micrograms/mL in the separate group. The anti-PRP geometric mean titers after the 18-month booster were 58.5 micrograms/mL in the combined group versus 55.3 micrograms/mL in the separate group.

CONCLUSION

The five-component DTaP vaccine may be combined with PRP-T vaccine without clinically significant immunologic interaction when given in a 2-, 4-, 6-, and 18-month schedule.

Long-term follow-up of duodenal ulcer in children before and after eradication of Helicobacter pylori

BACKGROUND

Helicobacter pylori is a well-known cause of chronic antral gastritis and plays an important role in the pathogenesis of peptic ulcer disease in adults. However, because of the relatively low incidence of duodenal ulcer in childhood, few studies have been directed specifically at the relation between the treatment of H. pylori infection and duodenal ulcer in children. An evaluation in a larger patient population is necessary to draw a conclusion.

METHODS

Twenty-six children with duodenal ulcer and H. pylori antral gastritis received triple therapy (amoxicillin, bismuth, and metronidazole) to investigate whether eradication of the organisms can promote healing and prevent relapse of the ulcers in children. Endoscopic examinations were performed before, 2 months, and 12 months after the beginning of treatment.

RESULTS

H. pylori infection was eradicated in 25 (96%) of the 26 patients who underwent upper endoscopic follow-up. Clinical improvement and ulcer healing were achieved in 24 (92%) of 26 children. During a mean follow-up of nearly 2 years, the annual ulcer relapse rate was estimated to be 9%.

CONCLUSIONS

Triple therapy is the treatment of choice for endoscopically proven duodenal ulcer and histologically proven H. pylori antral gastritis in children. It strongly supports a causal relation between H. pylori and duodenal ulcer disease in children.

Comparison of once daily cefpodoxime proxetil suspension and thrice daily cefaclor suspension in the treatment of acute otitis media in children

An open-labeled and randomized trial was conducted to compare the efficacy and safety of once daily cefpodoxime proxetil suspension (10mg/kg/day) and thrice daily cefaclor (45mg/kg/day) in the treatment of acute otitis media in children. A total of 57 children aged from 6 months to 9 years were enrolled; 23 were treated with cefpodoxime and 34 with cefaclor. Satisfactory clinical outcome, either cure or improvement, was achieved at the end of treatment in 90% of patients in the cefaclor group and 95% of patients in the cefpodoxime group (p > 0.05). Clinical recurrence was identified at the follow-up visits in one case of the cefaclor group (3%), and none in the cefpodoxime group (p > 0.05). These drugs were well tolerated by 14/21 (67%) in the cefpodoxime-treated group and 27/32 (84%) in the cefaclor-treated group. The incidence of adverse events was slightly higher in the cefpodoxime group than in the cefaclor group, however the difference did not reach statistical significance (p > 0.05). The daily cost of once-daily cefpodoxime was lower than that of thrice-daily cefaclor. We conclude that cefpodoxime administered once daily is as effective and safe as cefaclor administered thrice daily in the treatment of acute otitis media in children. The less dosing frequency and lower daily price of cefpodoxime provide additional benefits.

Immunogenicity and safety of Haemophilus influenzae type b conjugate vaccine (HibTITER) and a combination vaccine of diphtheria, tetanus, pertussis and HibTITER (TETRAMUNE) in two-month-old infants

A study was undertaken to evaluate the safety and immunogenicity of a combination vaccine (TETRAMUNE) of conjugate Haemophilus influenzae type b (Hib) vaccine (HibTITER) and DTP (Diphtheria, Tetanus and Pertussis) vaccine. A total of 93 healthy children were randomized to receive either TETRAMUNE (combined group), or DTP and HibTITER administered concurrently (separate group) in separate syringes at approximately 2, 4 and 6 months of age in Taiwan. Serologic responses were largely comparable between the two vaccine groups; almost all subjects were seropositive to Hib PRP (polyribosylribitol phosphate) and were protected against diphtheria and tetanus after 2 doses of vaccine and mounted prominent responses to the components of Bordetella pertussis. Subjects in the combined group did not experience more adverse reactions compared with those in the separate group. We concluded that HibTITER was highly immunogenic and safe when administered concurrently with DTP vaccine to Taiwanese children. TETRAMUNE was also safe and immunogenic and might reduce the number of injections to achieve the same protection.

Perinatal candidiasis and transient maternal candidemia: report of one case

A premature infant who contracted candida pneumonia and candidemia early in the postnatal period was reported. Fungal hyphae was found in the pus-like gastric aspirate soon after birth, giving the first clue to the diagnosis and prompting an early institution of antifungal therapy. Maternal candidemia was documented in the immediate postpartum period, which resolved spontaneously without specific antifungal treatment.

Bacteremia and fungemia in hematological and oncological children with neutropenic fever: two-year study in a medical center

A retrospective study of bacteremia in children with neutropenic fever admitted to a medical center in Taiwan from Jan. 1994 to Dec. 1995 was performed. There were in total 273 episodes of neutropenic fever during this period, but only 79 pathogens were isolated from blood specimens in 70 episodes. Klebsiella pneumoniae (27.8%), E. coli (10.1%), Staphylococcus aureus (10.1%) and Pseudomonas aeruginosa (7.6%) were the most common pathogens. All the isolates of S. aureus were methicillin sensitive. About half of K. pneumoniae (10/22) was multiple-drug resistant. There were seven infection-related mortality cases, three due to multiple-drug resistant K. pneumoniae, one due to S. aureus, one alpha-hemolytic streptococcus and two fungemia (Cryptococcus neoformans and Fusarium sp.). Vancomycin is not necessary in initial empiric therapy of neutropenic fever, while cefazolin or oxacillin may be included in cases with central venous access device. Antibiotics to cover intestinal flora, especially K. pneumoniae, are paramount in our hospital.

Precore stop codon mutant in chronic hepatitis B virus infection in children: its relation to hepatitis B e seroconversion and maternal hepatitis B surface antigen

BACKGROUND/AIMS

The aims of this study were to investigate the significance of the precore stop codon mutant in the natural course of hepatitis B virus infection in children, and the influence of maternal transmission.

METHODS

Sequential sera from 80 hepatitis B virus carrier children both before and after e seroconversion during long-term follow-up were studied using the polymerase chain reaction-amplification created restriction site method. Direct sequencing of the precore region was performed in 89 sera from 32 of the 80 children.

RESULTS

The precore stop codon mutant coexisting with wild strain was found in 10% of children initially, and later in 25% of children before e seroconversion. After e seroconversion, wild type was still present in 75% and mutant in 39% of children at the end of follow-up. The mutant alone was present in 15% of anti-HBe positive children without concomitant aminotransferase elevation. Children with earlier emergence of this mutant tended to have higher peak aminotransferase levels. This mutant emerged less frequently in children of hepatitis B virus carrier mothers (37.5%) than in those of non-carrier mothers (65%) (p<0.05).

CONCLUSIONS

These observations suggest that this mutant is selected by host immune pressure, but is not an initiator in the loss of immune tolerance during childhood chronic hepatitis B virus infection.

Mononucleosis syndrome and coincidental human herpesvirus-7 and Epstein-Barr virus infection

Two girls (a 5 year old and a 21 month old) experiencing mononucleosis syndrome with coincidental human herpesvirus (HHV)-7 and Epstein-Barr virus (EBV) infections are described. One patient had primary HHV-7 infection and reactivated EBV infection. The other had primary HHV-7 and EBV infections. These cases indicated that HHV-7 is capable of inducing infectious mononucleosis-like illness. Multiple herpesvirus infection in one of the patients also suggests that interaction among herpesviruses can occur in vivo. The consequence of this interaction may have clinical implications.

Diphtheria, tetanus and whole cell pertussis vaccine combined with hepatitis B vaccines: a comparison of two doses (10 microg and 5 microg)

BACKGROUND

A combined diphtheria-tetanus-whole cell pertussis-hepatitis B (DTPwHB) vaccine might facilitate the achievement of universal vaccination of infants against hepatitis B.

METHODS

A double blind, randomized, two-armed, single center study was undertaken to evaluate the immunogenicity and reactogenicity of combined tetravalent DTPwHB vaccine, with two dosages of hepatitis B component (10 microg and 5 microg). The combined vaccine was tested in the context of a simplified vaccination schedule at 1.5, 3.5 and 6 months of age, to 120 healthy infants born to hepatitis B surface antigen-negative mothers after priming with one dose of hepatitis B vaccine (10 microg) at birth. Antibodies to each antigenic component were measured from blood samples collected immediately after birth, pre- and postvaccination blood samples.

RESULTS

The reactogenicity profiles were similar in the two groups. No serious adverse events were reported. One month after completion of the four-dose vaccination schedule, all subjects except one in Group 1 (10 microg) had protective titers of anti-HBs (10 mIU/ml). At this time the geometric mean titer in Group 1 (10 microg) was higher than that observed in Group 2 (5 microg), 696 vs. 488 mIU/ml (P = 0.19). One month after three doses all subjects in both groups had protective antidiphtheria titers and antitetanus titers. The vaccine response rate to the Bordetella pertussis component of the vaccine was 88.0% in Group 1 and 96.2% in Group 2 (P = 0.86).

CONCLUSION

Both combined tetravalent vaccines are safe and immunogenic when administered to infants born to a hepatitis B surface antigen-negative mother, with a 10-microg dose of priming hepatitis B vaccine at birth. This combined tetravalent DTPwHB vaccine may play an important role to promote integration of HB vaccine into the Expanded Program of Immunization in hepatitis B-endemic areas.

Absolute ethanol embolotherapy for hemangioma with Kasabach-Merritt syndrome

This report describes a female baby having a hemangioma over the right thigh that had appeared as an irregular bruise since two days old. Severe thrombocytopenia, consumptive coagulopathy, anemia, and heart failure developed at three months old. With a diagnosis of Kasabach-Merritt syndrome, systemic corticosteroid, vincristine, subcutaneous alpha-interferon, and massive plate transfusion were given. However, the platelet count remained low and the skin lesion enlarged gradually. Trans-feeding-arterial embolotherapy with a 5 ml pure ethanol (1 ml/kg) injection was performed at four months of age. Thirty days later, her platelet count recovered and the hemangioma shrunk in size. This case illustrates that absolute ethanol embolotherapy is an effective treatment for hemangioma with Kasabach-Merritt syndrome and may be life-saving for those with lesions refractory to medical therapy.

Follow-up immunogenicity of an inactivated hepatitis A virus vaccine in healthy children: results after 5 years

Long-term persistence of hepatitis A virus (HAV) serum antibody in vaccinated children has not been demonstrated in previous studies. To study the long-term immunogenicity to HAV vaccine, three doses of strain HM 175 HAV vaccine with 360 enzyme-linked immunosorbent assay units were administered to 107 children, aged from 1.0 to 6.8 years, at 0, 1, and 6 months. The administration of one vaccine dose induced seropositivity (anti-HAV titer > or = 20 mIU ml-1) in 95% of all vaccinees at month 1. All subjects remained seropositive until month 6. The titers of HAV antibody remained above 20 mIU ml-1 in all subjects followed up to 60 months. The geometric mean titer (GMT) reached its peak (3802 mIU ml-1) at month 7, i.e. 1 month after the booster dose, and then declined until the end of follow-up at month 60 (661 mIU ml-1). A trend of higher GMT in female subjects persisted up to month 60. The changes of the GMT over time were best described by the regression equation: log (GMT) = 3.26-0.08 x (age in years) (r = -0.95, P = 0.014). According to this equation, the geometric mean concentration would reach 20 mIU ml-1 at around 24.5 years after the beginning of vaccination. In conclusion, those who completed the recommended three-dose inactivated HAV vaccination series remained seroprotective for at least 5 years. Theoretically, such a vaccination program can provide a protective period of over 20 years in children. This paper may be the first to describe at least 5-year immunogenicity of inactivated HAV vaccination in healthy children.

Evaluation of a live attenuated varicella vaccine in 15- to 18-month-old healthy children

A clinical trial was conducted in Taiwan in 15- to 18- month-old healthy children to study the reactogenicity and immunogenicity of live varicella vaccine combined with standard measles-mumps-rubella vaccine. A total of 118 varicella antibody-negative children were enrolled. They received one dose of varicella vaccine and one dose of measles-mumps-rubella vaccine at the same time. The vaccines were well tolerated; adverse reactions were mild and infrequent, with 2% of vaccines developed skin rash. No vesicular rash was seen. Concomitant varicella vaccination did not significantly increase the incidences of reactions associated with MMR vaccine. The seroconversion rates to varicella, measles, mumps and rubella all approached 100%. This study confirmed that simultaneous administration of live attenuated varicella vaccine and MMR vaccine was safe and immunogenic in healthy young children in Taiwan.

Systolic function, readmission rates, and survival among consecutively hospitalized patients with congestive heart failure

We sought to describe the relation between left ventricular systolic function and rates of hospital readmission and survival among consecutively hospitalized patients with congestive heart failure. Medical records were reviewed for these patients at an academic medical center between Jan. 1, 1992, and Dec. 31, 1993. Left ventricular systolic function assessments performed within 6 months before discharge were used to classify left ventricular systolic function. Hospital readmission rates and survival through Dec. 31, 1994, were compared between patients with systolic dysfunction and those with preserved systolic function. Among 412 patients hospitalized with a primary diagnosis of congestive heart failure, 224 had undergone a left ventricular function assessment during the 6 months before hospital discharge. In-hospital mortality and readmission rates were higher among patients without a recent assessment of left ventricular systolic function. Of patients with systolic dysfunction, 55% versus 41% of patients with preserved systolic function were either readmitted or had an emergency room visit within 6 months after discharge (p = 0.06). At 27 months' follow-up, cumulative survival probabilities were 65% for patients with preserved systolic function, 65% for patients with systolic dysfunction, and 60% for patients without a left ventricular systolic function assessment (p = 0.24). Patients without a recent left ventricular systolic function assessment have significantly higher hospital readmission rates than patients with a recent systolic function assessment. Among hospitalized patients, mortality rates are comparable between patients with systolic dysfunction and those with preserved systolic function. However, patients with heart failure with systolic dysfunction may have higher readmission rates.

Human intestinal permeability of piroxicam, propranolol, phenylalanine, and PEG 400 determined by jejunal perfusion

PURPOSE

To determine the human jejunal permeabilities of compounds utilizing different transport mechanisms using a regional perfusion approach and to establish a standard procedure for determining drug permeability class to be used for the establishment of drug product bioequivalence standards.

METHODS

Six healthy male volunteers participated in this study. A multi-lumen perfusion tube was inserted orally and positioned in the proximal region of the jejunum. A solution containing piroxicam, phenylalanine, propranolol, PEG 400 and PEG 4000 was perfused through the intestinal segment at a rate of 3.0 ml/min. Perfusate samples were quantitatively collected every 10 minutes for two 100 minute periods with an intermediate wash out period to determine intra and intersubject variation.

RESULTS

The mean P(eff) (+/-SD) of piroxicam, phenylalanine, propranolol, and PEG 400 were 10.40 +/- 5.93, 6.67 +/- 3.42, 3.59 +/- 1.60, 0.80 0.46 x 10(-4) cm/sec, respectively. The coefficient of variation for the intersubject variability, first and second perfusion periods were: piroxicam, 60.5% and 57.1%; phenylalanine, 52.8% and 57.8%; propranolol, 62.1% and 44.6%; and PEG 400, 81.7% and 42.3%, indicating a slightly lower CV for the second perfusion period in the same subject. The intrasubject CV's between the two perfusion periods were: 19.4%, 21.3%, 23.6% and 41.0% respectively, indicating a smaller intraindividual variation for all compounds studied.

CONCLUSIONS

Piroxicam, a nonpolar drug exhibited the highest permeability of the compounds studied. The intrasubject CV was lower than the intersubject CV, indicating consistent permeability estimation within subjects. The methodology is useful for permeability estimation regardless of absorption mechanism and can be used to establish a consistent data base of human permeabilities for estimation of human drug absorption and for establishing the biopharmaceutic permeability class of drugs.

Hepatitis B vaccination in preterm infants

AIM

To investigate the immunogenicity and safety of existing recommendations for hepatitis B vaccination in preterm infants.

METHODS

Recombinant hepatitis B vaccine (H-B-VAX II, 5 micrograms per dose) was given to 85 preterm infants divided into two groups, using two different schedules. Forty four group A infants with birthweights of < 2000 g received three doses at 1, 2, and 7 months of age. Forty one group B infants with birthweights of > or = 2000 g received three doses at 0, 1, and 6 months of age.

RESULTS

After vaccination, 42 infants from group A (95%) and 37 infants from group B (90%) developed protective levels of antibody. The final seropositive rate and the geometric mean concentration of hepatitis B surface antibody between the two groups were not significantly different. The immune response of preterm infants to hepatitis B vaccines was similar to that of term infants in a previous study.

CONCLUSIONS

Preterm infants can be given hepatitis B vaccines using one of the above two different schedules, at a cutoff birthweight of 2000 g.

Detection of hepatitis B surface gene mutation in carrier children with or without immunoprophylaxis at birth

To investigate the clinical significance of mutation in hepatitis B virus (HBV) surface gene, DNA sequence analysis of the "a" determinant was performed on sera from 27 carrier children with immunoprophylaxis, their mothers, and 21 carriers without vaccination. A precore mutant (G to A) at nucleotide 1896 was detected in sera from 11 carriers without vaccination. Mutations in the "a" determinant were detected in 6 (22%) of the vaccinated children. Four HBV strains showed a Gly-to-Arg mutation at the 145th codon of the surface gene. Amino acid substitutions at amino acid 133 and 144 were noted in the other 2 children. Only 1 mother had the same predominant strain of mutant virus as her child. These observations indicate that immune pressure exerted by immunoprophylaxis at birth may select for a mutant virus.

Correlation of quantitative renal cortical echogenicity with renal function in pediatric renal diseases

Using quantitative echogenicity, the correlation between renal cortical echogenicity and renal function (serum creatinine) was evaluated in pediatric renal diseases. The kidney/liver echogenicity ratio (K/ L ratio) was measured by computerized amplitude histogram in 20 healthy children as well as in 45 children with renal diseases, including 12 glomerulonephritis with chronic renal failure (CRF), 9 anatomic-related CRF, 9 glomerulonephritis with acute renal failure (ARF), 5 nephrotoxic ARF, and 10 glomerulonephritis without renal failure. All children were above six years of age. Simultaneous serum creatinine was available during the procedure in all patients. The overall K/L ratio was 1.38 +/- 0.26 for CRF and 1.14 +/- 0.18 for ARF (p = 0.007), while the overall serum creatinine was 312 +/- 160 mumol/L (3.5 +/- 1.8 mg/dl) and 191 +/- 73 mumol/L (2.2 +/- 0.8 mg/dl), respectively (p = 0.013). K/L ratio was higher in CRF at a higher, or even at a comparable serum creatinine level, than in ARF. For patients with glomerulonephritis, K/L ratio was highest in those with CRF, next in those with ARF. Even in glomerulonephritis without renal failure, the K/L ratio was higher than in normal controls. There was a positive correlation between K/L ratio and serum creatinine concentration in glomerulonephritis with or without renal failure (r = 0.69, p < 0.001). These results suggest that the degree of increased renal echogenicity may reflect the severity of the renal disease. The K/L ratio measured by quantitative echogenicity may provide an additional simple noninvasive method to monitor the progression of glomerulonephritis.

Outbreak of scarlet fever at a hospital day care centre: analysis of strain relatedness with phenotypic and genotypic characteristics

An outbreak of scarlet fever involving 12 children occurred at a hospital day care centre from February to March 1996. Twenty-five throat isolates of Streptococcus pyogenes (GAS, group A streptococcus) available from 24 children, including 10 children with scarlet fever and 14 asymptomatic carriers, and one asymptomatic staff member were studied for the presence of genes encoding streptococcal pyrogenic exotoxin types A (speA), B (speB), and C (speC) and for protease activity. Antimicrobial susceptibilities using the E-test, cluster analysis by cellular fatty acid composition and random amplified polymorphic DNA (RAPD) patterns by means of arbitrarily-primed polymerase chain reaction (APPCR) of the isolates were performed to investigate the outbreak. Only one isolate from an asymptomatic child possessed the speA gene. All isolates possessed the speB gene and 24 (96%) isolates were positive for the speC gene. There was no difference in protease activity between isolates from children with scarlet fever and from asymptomatic carriers. Thirteen isolates (10 recovered from children with scarlet fever, two from asymptomatic children, and one from the staff member) were considered to be the same strain according to the identical antimicrobial susceptibility profile and RAPD patterns and were also considered to be similar by cluster analysis of fatty acid composition. These findings suggest that the outbreak was caused by a unique clone of GAS. We conclude that RAPD typing and cluster analysis by cellular fatty acids composition both provide a powerful tool for epidemiological investigation of GAS infections.

A simplified schedule to integrate the hepatitis B vaccine into an expanded program of immunization in endemic countries

OBJECTIVE

To investigate the safety, immunogenicity, and efficacy of a simplified hepatitis B vaccination schedule.

METHODS

The second dose of hepatitis B vaccine and the first dose of diphtheria-tetanus-pertussis (DTP) vaccine were given simultaneously at age 6 weeks. The second dose of DTP vaccine was given at age 3.5 months. The third dose of DTP vaccine and the third dose of hepatitis B vaccine were given at age 5.5 months. One hundred three infants (group A) born to mothers without hepatitis B surface antigen (HBsAg) received DTP with whole-cell pertussis vaccine. Fifty-five infants (group B) born to mothers with HBsAg and hepatitis B e antigen received DTP with acellular pertussis vaccine.

RESULTS

By age 9 months, none of group A and 4 (7%) group B infants were sero-positive for HBsAg. The protective efficacy against the hepatitis B carrier state in these infants at high risk was 92%. Antibody to hepatitis B surface antigen was 10 mlU/ml or greater in 99 (96%) of group A infants and in 50 (91%) of group B infants. Both the acellular and whole-cell DTP vaccines were immunogenic, and the incidences of adverse reactions were within an expected and acceptable range.

CONCLUSIONS

The simplified vaccination schedule to integrate the hepatitis B vaccine into the Expanded Programme of Immunization was safe, Immunogenic, and effective. This schedule may improve vaccine compliance and be applied to DTP and hepatitis B combination vaccines now under investigation.