Burkitt lymphoma in a child with Bloom syndrome.

BACKGROUND: Bloom syndrome is a rare disease characterized by chromosomal instability and increased risk of developing lymphoma. OBSERVATION: We report on a case of Bloom syndrome in a 5-year-old boy with Burkitt lymphoma. The diagnosis was suspected by growth retardation, repeated respiratory infections, facial telangiectasia, and a low immunoglobulin level, then confirmed cytogenetically by sister chromatid exchanges. Chemotherapy was poorly tolerated, which required reducing the doses. Unfortunately, it was not sufficient to control the neoplasm and the patient died 14 months after diagnosis. CONCLUSIONS: Cancers in Bloom syndrome are a challenge since the potentially life-threatening side effects of the chemotherapy may require modifications in standard treatment such as dose reduction, which can compromise the tumor prognosis.

Therapeutic drug monitoring in de novo kidney transplant receiving the modified-release once-daily tacrolimus.

INTRODUCTION: Advagraf (AVF) a new formulation of tacrolimus (TRL), allows once-daily administration while showing similar efficacy and safety to the conventional Prograf (PGF), which is prescribed twice daily. Our study sought to compare short-term therapeutic drug monitoring (TDM) of AVF and PGF in de novo kidney transplants. PATIENTS AND METHODS: We retrospectively collected results of TDM performed on blood trough samples (C0) using an LC- MS/MS assay to quantify TRL exposure in the two groups. Twelve subjects received initial immunosuppression with AVF associated with mycophenolic acid, steroids, and immunoglobulins. We compared median doses and C0 levels with those obtained in 18 cases receiving an equivalent dose of PGF during the same period. RESULTS AND DISCUSSION: Although both groups showed similar mean C0, the median dose in the AVF group tended to be higher than the PGF group-respectively, 9.8 and 7.9 mg/d-which may be attributed to the once-daily regimen, which inevitably results in lower C0 levels compared to the twice-a-day regimen, while overall exposure appeared similar in terms of area under the curve (AUC). This observation occurred especially during the first weeks despite the extended release formulation. In fact, one patient who showed a low C0 (5.9 ng/mL) while receiving high doses of AVF (0.28 mg/kg), the AUC of 356 and 211 ng.h/mL performed on days 12 and 18 respectively showed exposure consistent with efficacy. CONCLUSION: In conclusion, it seemed to be necessary to use higher doses (25%) of Advagraf to reach the targeted C0 levels during the first weeks posttransplant. For patients who do not reach the targeted C0 despite high doses, TRL exposure should be assessed by AUC or peak levels (C4h).