Immunogenicity of the hepatitis A vaccine 20 years after infant immunization

To determine the duration of immunity provided by the Hepatitis A vaccination (HepA), we evaluated a cohort of participants in Alaska 20 years after being immunized as infants. At recruitment, participants received two doses of inactivated HepA vaccine on one of three schedules. We conducted hepatitis A antibody (anti-HAV) testing for participants at the 20-year time-point. Seventy-five of the original 183 participants (41%) were available for follow-up. The overall anti-HAV geometric mean concentration was 29.9 mIU/mL (95% CI 22.4 mIU/mL, 39.7 mIU/mL) and 50 participants (68%) remained seropositive (titer ≥ 20 mIU/mL). Using a fractional polynomial model, the predicted percent seropositive at 25 years was 55.3%, 49.8% at 30 years and 45.7% at 35 years, suggesting that the percent sero-positive could drop below 50% earlier than previously expected. Further research is necessary to understand if protection continues after seropositivity diminishes or if a HepA booster dose may become necessary.

Computed tomography versus bronchography in the diagnosis and management of tracheobronchomalacia in ventilator dependent infants

AIM

To assess the relative accuracy of dynamic spiral computed tomography (CT) compared with tracheobronchography, in a population of ventilator dependent infants with suspected tracheobroncho-malacia (TBM).

SETTING

Paediatric intensive care unit in a tertiary teaching hospital.

PATIENTS AND METHODS

Infants referred for investigation and management of ventilator dependence and suspected of having TBM were recruited into the study. Tracheobronchography and CT were performed during the same admission by different investigators who were blinded to the results of the other investigation. The study was approved by the hospital research ethics committee, and signed parental consent was obtained.

RESULTS

Sixteen infants were recruited into the study. Fifteen had been born prematurely, and five had cardiovascular malformations. In 10 patients there was good or partial correlation between the two investigations, but in six patients there was poor or no correlation. Bronchography consistently showed more dynamic abnormalities, although CT picked up an unsuspected double aortic arch. Radiation doses were 0.27-2.47 mSv with bronchography and 0.86-10.67 mSv with CT.

CONCLUSIONS

Bronchography was a better investigation for diagnosing TBM and in determining opening pressures. Spiral CT is unreliable in the assessment of TBM in ventilator dependent infants. In addition, radiation doses were considerably higher with CT.

MRI of retroperitoneal collections: a comparison with CT

Retroperitoneal collections in the absence of pancreatitis are rare. Imaging plays an important role in determining the aetiology of these collections and in allowing percutaneous drainage to be performed safely. A review of the imaging characteristics on both CT and MRI is presented, highlighting the advantages and disadvantages of these two modalities and their complimentary roles.

Hepatitis A vaccine administration: comparison between jet-injector and needle injection

INTRODUCTION

Type A hepatitis virus (HAV) is a serious health problem throughout the world and can be spread via fecal-oral contact. Both immune globulin and an HAV vaccine provide protection, but the vaccine gives complete protection. Efficacy of methods of vaccination in relation to the formation of anti-HAV antibodies is unclear; thus, this study seeks to determine if significant differences exist between the syringe as compared to the jet injection technique. The purpose of this study was to compare in a randomized trial Biojet jet-injection system to a needle-syringe method. To determine if a significant difference between these two methods in seroconversion rates or geometric mean titers of anti HAV antibody occurs at day 15, 30, and 210 days after vaccination.

METHOD

Anti-HAV IgG(-) adult hospital employees were randomized to receive 1440 EL.U of hepatitis a vaccine (HAVRIX(R)) in 2 doses by either needle or jet-injector (Biojector(R)) system at month 0 and 6. HAV seroconversion titer results were measured by the Boehringer-Mannheim method.

RESULTS/DISCUSSION

A higher proportion of persons who received HAV vaccine via the Biojector(R) seroconverted with anti-HAV level >/=20 mIU at day 15, 30, and month 7 when compared with a needle injection.Side-effect profiles reported by participants in both methods were below those identified in current published and insert information, but the Biojector(R) had greater local reactivity in all categories when compared to the needle method.

P53 autoantibodies in 1006 patients followed up for breast cancer

Serial plasma samples from 1006 patients with breast cancer revealed: (i) no correlation of p53 autoantibody status with disease status at the time of sample collection, or with menopausal status at time of primary diagnosis of breast cancer; (ii) 155 out of 1006 (15%) of patients were positive for p53 autoantibodies, and these patients tended to have a persistent autoantibody status throughout follow up, irrespective of disease behaviour; and (iii) where a negative autoantibody status was found at primary diagnosis of breast cancer, this negative status persisted throughout follow up, irrespective of later disease behaviour. We conclude that screening for p53 autoantibody status is not informative on residual tumour activity nor on therapeutic responsiveness.

Evidence to support a change in follow-up policy for patients with breast cancer: time to first relapse and hazard rate analysis

The ideal follow-up for patients with cancer should be sensitive to the likelihood of relapse, for prompt investigation and treatment if indicated, together with the support of patient confidence. The current British Association of Surgical Oncologists guidelines for patients with breast cancer suggest intensive follow-up, including 3-monthly clinic visits during the first 2 years. These recommendations place increasing demands on clinical resources. The combined outcome of screening, early detection, dedicated clinical services that emphasize rapid diagnosis and concomitant improved survival, have resulted in increasing absolute numbers of diagnosed breast cancer patients in follow-up clinics. This article examines the follow-up of breast cancer patients to determine if the convention should be adjusted to obtain more from current resources while maintaining equivalent patient care. The data on all patients with breast cancer attending one general oncology clinic were examined in order to determine the pattern of relapse. Analyses identified: (1) the time to relapse at any site and at specific sites; and (2) the prognostic significance of three factors for subsequent relapse, namely nodal status, menopausal status and T stage at diagnosis. In 416 consecutive patients, the annual rate of relapse of breast cancer was found to increase progressively over the first 4 years. Nodal disease was the most important single variable as a predictor of relapse. The annual hazard rate for relapse for node positive patients in the first year was 5%; this increased to 10% and 14% in years three and four respectively. In contrast, in those patients who were node negative at diagnosis (302/416; 73%), the hazard rate for relapse was 1% in year one, increasing to 5% in years three and four. Intensive early follow-up of breast cancer patients provides no clear clinical gain for the great majority of patients, since early relapse is rare in the first year. The use of clinical funds and staff resources might be optimized to focus clinical follow-up on those patients at risk of recurrence. We suggest that all patients should continue to be monitored and receive psychological care through access to their general practitioner, skilled breast care nurses and specialized counsellors. Any patient at risk, or developing symptoms of relapse, would have immediate clinical access to the oncologist for diagnostic investigations. This strategy would optimize psychological patient care and use the full backup of clinical resources during the prolonged period over which relapse becomes more probable.

Precipitation of morphine withdrawal syndrome in rats by administration of mu-, delta- and kappa-selective opioid antagonists

The acute effects of opioid drugs are generally hypothesized to be mediated by multiple receptors, for which three types of binding sites have been established. In order to evaluate the selective participation of each type of opioid receptor in opiate withdrawal, the opiate withdrawal syndrome, precipitated by the intraventricular acute administration of mu-, delta- and kappa-selective opioid antagonists was investigated. After implantation of the cannula into the lateral ventricle, rats were made physically dependent by subcutaneous insertion of two 75-mg pellets of morphine (base). D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2 (CTAP) (5-5000 ng), a mu-selective opioid antagonist, naltrindole (62-2000 ng), a delta-selective antagonist or nor-binaltorphimine (nor-BNI) (600-20,000 ng), a kappa-selective antagonist, were administered 72 hr after implantation of the pellets. All three drugs elicited some signs of morphine withdrawal but they differed in both their potency and their efficacy. The most efficacious and the most potent was CTAP, eliciting 8 of the 14 withdrawal signs at doses of 5-5000 ng. Nor-BNI was less efficacious and less potent, eliciting a significant increase in 5 of the 14 withdrawal signs in a dose range of 600-20,000 ng. Naltrindole was the least potent and least efficacious of the three drugs, eliciting a significant increase of only 2 withdrawal signs after intraventricular administration of 2000 ng. In a second experiment, the withdrawal syndrome was precipitated by the combined administration of CTAP+naltrindole or CTAP+nor-BNI. The severity of withdrawal, obtained with these two combinations, was similar to that observed with CTAP alone. These results support the importance of the mu receptor in the expression of central opiate dependence and suggest a minor role for delta and kappa receptors.