Chronic lymphocytic leukemia is infrequent in Mexican mestizos.

Chronic lymphocytic leukemia (CLL) is the most frequent leukemia in adults living in Western countries, and accounts for approximately 30% of adult leukemias. In a 15-year period in a single institution, we identified 19 patients with CLL in a group of 211 adults with leukemia (9% of adult leukemias). Of these 19 CLL patients, 8 had a Caucasian phenotype, 4 were born outside the country, and only 11 were Mexican mestizos. On the other hand, in a multicenter experience involving 1968 Mexican adults with leukemia, CLL represented 6.6% of the cases, a figure significantly lower than that reported in Caucasians (P < 0.01). CLL is the least frequent type of leukemia in Mexican mestizos, and this low prevalence may stem from the genetic origin of this racial group. The data also suggest a genetic predisposition of Caucasians to suffer from this disease.

Splenectomy complications in hematological diseases.

The postoperative complications observed in a group of 27 patients with hematological diseases that underwent splenectomy are reported: 21 patients had a non-malignant hematological condition, whereas the rest had a hematological malignancy. Seven complications presented in 6 patients (two wound infections, two severe post-operative hemorrhages, one incisional hernia, one sepsis by capsulated bacteria and one fatal hemophagocytic syndrome). The overall complication rate was 27%, whereas the fatal complication rate was 3%. The complication rate in patients with malignant diseases was 83%, whereas that in benign conditions was 9%. The size of the spleen was related with the complication rate (median weight of patients with complications was 990 g versus 132 g in those without complications; p < 0.01). The two patients that underwent splenectomy before age six months had complications, in one case related to parental negligence. In splenectomies performed for hematological disease the benefits must be balanced carefully against the risks.