Detection of molecular variants of BCR-ABL gene in bone marrow and blood of patients with chronic myeloid leukemia by reverse-transcriptase polymerase chain reaction (RT-PCR).

Very limited data exists in Thailand regarding the frequency of BCR-ABL leukemic gene and its prognostic implication in Thai CML patients. The objective of this study was to develop a rapid molecular assay for the detection of the two most commonly reported variants of BCR-ABL fusion gene, B2A2 and B3A2 in CML patients. Bone marrow or peripheral blood were used for RNA extraction and reverse-transcribed to cDNA for PCR amplification. 92 per cent of CML patients (91/99) were positive for BCR-ABL gene (61% B3A2 and 31% B2A2). 8/99 CML patients were BCR-ABL-negative. B3A2 and B2A2-positive patients did not have any different clinical and hematological features at presentation although B3A2 patients tended to be slightly older and had higher platelet counts. 71/71 non-CML including other MPD and leukemia cases were all negative for BCR-ABL gene. In conclusion, a rapid RT-PCR assay has now been developed for the detection of this hallmark gene in CML patients. It should be of great value in the differential diagnosis of CML from other diseases. Long-term follow-ups of CML patients with different variants are needed to determine the prognostic importance of each gene variant.

Serum transcobalamin II level in glucose-6-phosphate dehydrogenase deficient subjects with typhoid fever.

Transcobalamin II (TCII) is the vitamin B12 binding protein which is responsible for delivery of this vitamin to the tissues. High values for serum TCII have been reported in many clinical conditions. This paper describes the elevated serum TCII levels in three G-6-PD deficient patients with typhoid fever. They had severe hemolysis with hemoglobinuria associated with slight liver dysfunctions but without obvious increased serum creatinine and BUN concentrations. A remarkable increase in serum TCII level was observed during active hemolysis and decreased to the normal level within 2-3 days after hemolysis ceased. The mechanism of increased serum TCII during hemolysis is probably due to hemoglobinuria secondary to excessive hemolysis. As Hb is known to be efficiently reabsorbed by the proximal tubule cells and can competitively inhibit the tubular uptake of TCII-B12. It is possible that excess Hb interferes with TCII uptake and degradation at renal tubular cells. Therefore, the circulating TCII survival is prolonged resulting in the elevated TCII level. Furthermore, lysosomal degradation of newly synthesized TCII is a normal process that regulates the TCII secretion. Therefore, a reduced lysosome-mediated uptake of TCII-B12 by renal tubular cell may stimulate the TCII secretion as has been shown experimentally in vitro.

Therapy of chronic idiopathic thrombocytopenic purpura in adults: experiences from Thailand.

Results of different types of treatment in 416 adults with chronic idiopathic thrombocytopenic purpura (ITP) were analyzed. Of 368 patients treated with corticosteroids, 278 (77%) achieved complete response (CR ie, normalization of platelet count). However, only 18% of patients had continued complete response (CCR). Results of splenectomy was analyzed in 126 patients, 49% of them achieved CCR and 76% of them had beneficial effects from the operation. Emergency splenectomy was a life saving procedure in 8 of 11 patients with life-threatening hemorrhage. Vinca alkaloids gave a 50% transient CR. Immunosuppressive agents (cyclophosphamide, azathioprine) resulted in only 11% CCR.