Different mechanisms may contribute to early T cell reconstitution in HIV-1-infected children and adolescents during ART: decreased activation-induced apoptosis leading to increased survival of circulating primed/memory T cells; decreased activation-induced naive-to-memory shift increasing the frequency of circulating resting/naive T cells; increased input of haematopoietic progenitor cells from the bone marrow into the thymus and decreased intrathymic T cell death leading to an increased thymic output of naive T cells.

Engerix-B administered on a 0-, 12-, and 24-month schedule is highly immunogenic. Providers should consider this alternate immunization schedule for children who are at low risk of immediate exposure to hepatitis B infections.

Background/Aims: Single cases of lithium carbonate dosing in hemodialysis patients have been published. We investigate the dose-serum level relationship after single and multiple lithium acetate dosing in a hemodialysis patient and review the literature. Methods: Lithium acetate was administered orally over a period of 11 months in a patient with major depressive episodes after being placed on hemodialysis three times a week. The serum trough levels of lithium before and after hemodialysis were analyzed. The data were compared with those reported in the literature, and potential drug interactions and the importance of the residual renal function are discussed. Results: No adverse events due to the lithium therapy were documented. Steady state levels of between 0.6 and 0.8 mmol/l of lithium acetate were achieved 17 days after initiating the therapy, using 24 mmol/l of lithium three times a week, in a patient with a residual diuresis of about 400 ml/day. In contrast, data reported in the literature implicate that only 9.6–14.4 mmol/l of lithium (450–600 mg of lithium carbonate) is sufficient to achieve adequate serum levels. Conclusions: The residual renal function can be important for lithium clearance. The creatinine clearance does not reflect this point.

We evaluated the use of a whole-blood assay that measures spontaneous and activation-induced CD69 expression on peripheral blood T-cells in vitro for assessment of T-cell function in HIV-1-infected paediatric patients. Heparinized venous blood from 28 HIV-1 positive children and adolescents and 23 healthy controls was incubated for 4 h with or without 5 microg/ml phytohaemagglutinin (PHA). Thereafter, analysis of CD69 expression on CD4+ and CD8+ T-cells was done by flow cytometry; simultaneously we determined CD4+ T-cell counts and plasma HIV-1 viral load. Neither spontaneous nor PHA-induced CD69 expression differed significantly between HIV-1 positive patients and healthy controls. However, T-cells from HIV-1 positive patients with plasma HIV-1 viral load levels above 70x10(3) copies/ml showed a higher spontaneous CD69 expression than T-cells from patients with lower plasma viral load levels in different stages of the disease. Antiretroviral treatment in four patients reduced spontaneous CD69 expression in CD4+ T-cells and PHA-induced CD69 expression in CD4+ and CD8+ T-cells significantly after 8 weeks of therapy. Conclusion Spontaneous and activation-induced expression of the early (activation) antigen CD69 on peripheral blood T-cells does not distinguish HIV-1 positive patients from HIV-1 negative healthy controls and is not correlated with peripheral blood CD4+ T-cell counts. This test may not be a reliable marker for functional T-cell deficiency during early stages of HIV disease. Increased spontaneous as well as PHA-induced CD69 expression on T-cells from HIV-1-infected children and adolescents in vitro may rather reflect HIV-induced pre-activation of T-cells in vivo.