Early mortality in children with advanced mature B-cell malignancies in a middle-income country.

Scant information about the early toxicity of high-dose chemotherapy regimens for the treatment of mature B-cell malignancies (B-non-Hodgkin lymphoma) in developing countries is available, so we performed a retrospective evaluation of children with B-non-Hodgkin lymphoma treated with Berlin-Frankfurt-Muenster-based protocols in Argentina (1993 to 2007). In the second protocol, induction chemotherapy was modified introducing high-dose cytarabine and etoposide (block CC) instead of high-dose methotrexate (block AA). Forty-one patients with stage III and elevated lactate dehydrogenase or stage IV or B-acute lymphoblastic leukemia were included. Five patients (12.1%) had an early death at a median of 23 days after treatment initiation, caused by sepsis in 4 and by a Stevens Johnson syndrome in 1. Children that had an early death were significantly more likely to present with renal failure (P=0.04) and have significantly higher levels of phosphate and creatinine on admission (P=0.02 and 0.008). Eighty percent of children dying early had prior extensive abdominal surgery and positive blood cultures after the first cycle. Induction with AA block was associated with a higher frequency of severe orointestinal toxicity (P=0.04). We conclude that renal failure was associated to increased risk of mortality leading to a higher risk of sepsis, especially in patients that underwent abdominal surgery.

Novel syntaxin 11 gene (STX11) mutation in three Argentinean patients with hemophagocytic lymphohistiocytosis.

INTRODUCTION: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disease with major diagnostic and therapeutic difficulties, basically comprising two different conditions: primary and secondary forms. Recent advances regarding molecular diagnosis may be useful to distinguish from one another, especially in sporadic cases starting in early infancy. MATERIALS AND METHODS: In this report, we evaluated three Argentinean patients with clinical suspicion of HLH, but without family history. We excluded mutations in the perforin gene but identified in the three patients a novel homozygous deletion (c. 581_584delTGCC; p.Leu194ProfsX2) in the gene-encoding syntaxin 11 (STX11), causing a premature termination codon. RESULTS AND CONCLUSION: Each parent from the three unrelated families resulted heterozygous for this deletion confirming the diagnosis of familial hemophagocytic lymphohistiocytosis type 4. Patients shared the same single-nucleotide polymorphism profile in STX11 gene, and genotyping at ten microsatellites surrounding this gene support the presence of a single-haplotype block carrying the novel mutation.