Detection of BCR-ABL kinase domain mutations in CD34+ cells from newly diagnosed chronic phase CML patients and their association with imatinib resistance

BCR-ABL kinase domain (KD) mutations, the most common cause of imatinib resistance, are infrequently detected in newly diagnosed chronic-phase chronic myeloid leukemia (CP-CML) patients. Recent studies indicate pre-existing mutations (PEMs) can be detected in a higher percentage of CML patients using CD34+ stem/progenitor cells, and these mutations may correlate with imatinib resistance. We investigated KD mutations in CD34+ stem cells from 100 CP-CML patients by multiplex ASO-PCR and sequencing ASO-PCR products at the time of diagnosis. PEMs were detected in 32/100 patients and included F311L, M351T, and T315I. After a median follow-up of 30 months (range 8-48), all patients with PEMs exhibited imatinib resistance. Of 68 patients without PEMs, 24 developed imatinib resistance. Mutations were detected in 21 of these patients by ASO-PCR and KD sequencing. All 32 patients with PEMs had the same mutations. In imatinib-resistant patients without PEMs, we detected F311L, M351T, Y253F, and T315I mutations. All imatinib-resistant patients without T315I and Y253F mutations responded to imatinib dose escalation. In conclusion, BCR-ABL PEMs can be detected in a substantial number of CP-CML patients when investigated using CD34+ stem/progenitor cells. These mutations are associated with imatinib resistance, and mutation testing using CD34+ cells may facilitate improved, patient-tailored treatment

Association Of BCR-ABL Alternative Splice Variants with Disease Progression, Treatment Response and Survival in Chronic Myeloid Leukemia Patients Treated with Firstline imatinib Monotherapy

Background: Alternative RNA splicing has diverse biological effects in heath as well as disease. It also contributes to cancer onset and progression. Chronic Myeloid Leukemia (CML) results due to BCR-ABL fusion oncogene that is created due to chromosomal translocation t [9; 22] [q34; q11]). BCR-ABL is target of tyrosine kinase inhibitors (TKIs). BCR-ABL through alternative splicing can generate b2a2, b3a2 and some other rare splicing variants. BCR-ABL variants may vary in their response to TKI treatment and disease progression potential, which is a major factor contributing to dismal treatment outcome in CML. Objective: The objective of this study is to investigate correlation of BCR-ABL splice variants with TKI treatment outcome and survival in three phases of CML that has rarely been studied previously.Methods: BCR-ABL splice variants were studied using reverse transcriptase PCR (RT-PCR). in 70 CML patients from three phases of CML who were receiving imatinib (TKI) treatment.Results: Frequencies of different BCR/ABL splice variants like b3a2, b2a2 and b3a2+b2a2 were 49 (70%), 15 (21.4%) and 6 (8.6%), respectively. Splice variant b2a2 were more common (53.3%) in chronic phase CML (CP-CML) while b3a2 had higher frequency in advanced phases of CML (44.9%). CML patients with b2a2 transcript had better complete cytogenetic response and major molecular response to TKI treatment overall (100% vs. 24.5%) as well as in CP-CML (100% vs. 85.7%) and superior survival when compared to patients with b3a2 splice variant. All patients who died had male gender, less than 33 years age, b3a2 transcript, advanced phases of CML and imatinib resistance.Conclusions: Splice variant b3a2 was associated with CML progression, poorer survival and inferior treatment outcome as compared to b2a2. Further investigations on BCR-ABL splice variants and their roles in CML pathogenesis can provide deeper insights into CML biology and new targets for BCR-ABL positive leukemia treatment.          Keywords: CML; BCR-ABL splice variants; Progression; Survival; Treatment outcome 

Renal Abnormalities in Patients with Sickle Cell Disease: A Single Center Report from Saudi Arabia

Patients with sickle cell disease (SCD) are at increased risk of serious morbidity and mortality. Renal abnormalities in SCD are well known but renal involvement in Saudi patients with SCD has not been studied. We sought to identify renal abnormalities in adolescent and adult Saudi patients with SCD. We prospectively studied 73 patients with SCD followed up at King Khalid University Hospital, Riyadh, Saudi Arabia from July 2005 to November 2006,. All patients underwent evaluation of kidney function and urine examination to detect proteinuria and other urinary abnormalities. In addition, 53 patients from the cohort had 24-hour urine collection to measure creatinine clearance and to quantitate proteinuria. The patient population consisted of 34 males (46.5%) and 39 females (53.5%) with a median age of 23 years (range 14-40). Proteinuria was present in 30 patients (41%). Creatinine clearance was low in 12 patients (22.5%) and seven of these patients had low or low-normal serum creatinine despite reduced creatinine clearance. Low serum creatinine was common and present in 28 patients (38%). Two patients had chronic renal failure and one of them is on regular dialysis. Other abnormalities detected include hematuria in seven patients (8.5%) and hemoglobinuria in 12 patients (14.5%). In conclusion, renal abnormalities are present in a significant number of Saudi patients with SCD and proteinuria is the most common abnormality. Serum creatinine may remain low or within low-normal range in SCD patients despite reduced creatinine clearance. As proteinuria is a risk factor for developing renal failure in future, routine screening of SCD patients is recommended for timely intervention in order to prevent or delay renal damage

Proteinuria in adult Saudi patients with sickle cell disease is not associated with identifiable risk factors

Renal involvement in patients with sickle cell disease (SCD) is associated with signi-ficant morbidity and mortality. Proteinuria is common in patients with SCD and is a risk factor for future development of renal failure. We sought to identify risk factors, if any, associated with pro-teinuria in adult Saudi patients with SCD. We studied 67 patients with SCD followed-up at the King Khalid University Hospital, Riyadh, Saudi Arabia. All patients underwent 24-hour urine collection to measure creatinine clearance and to quantify proteinuria. In addition, blood was examined for evaluation of hematological and biochemical parameters. Clinical information was gathered from review of the patients′ charts. A urine protein level of more than 0.150 grams/24 hours was consi-dered abnormal. Urine protein was correlated with various clinical and laboratory parameters. Thirty-one males and 36 females were evaluated. The mean age of the cohort was 23.8 (± 7.2) years. Twenty-seven patients (40.3%) had proteinuria of more than 0.150 grams/24 hours. The study group had a mean hemoglobin level of 8.5 (± 2.8) g/dL and mean fetal hemoglobin (HbF) level of 14.4% (± 7.3%). Majority of the patients (61) had hemoglobin SS genotype and six patients had S-β⁰ thala-ssemia. None of the parameters evaluated correlated with proteinuria although there was a border-line association with older age and higher systolic blood pressure (P = 0.073 and 0.061 respec-tively). Hydroxyurea use for more than a year was not beneficial. In conclusion, our study suggests that proteinuria in adult Saudi patients is not associated with any clear identifiable risk factors

Response to rituximab in a refractory case of thrombotic thrombocytopenic purpura associated with systemic lupus erythematosus

Thrombotic thrombocytopenic purpura (TTP) is a serious disorder with a significant morbidity and mortality. Majority of cases of TTP are idiopathic, but some cases may be secon-dary to connective tissue diseases. TTP has been rarely associated with systemic lupus erythe-matosus (SLE) and may be refractory to treatment with plasma exchange, requiring immuno-suppressive therapy. We describe a patient with TTP and SLE who was refractory to plasma exchange and corticosteroids but responded to anti-CD20 antibody rituximab with continued re-mission after eight months of follow-up. Rituximab appears to be an effective treatment in re-fractory cases of TTP associated with SLE

Frank hematuria as the presentation feature of acute leukemia

Muco-cutaneous bleeding is a common presenting feature of acute leukemias. Mucosal bleeding usually manifests as gum bleeding and/or epistaxis but may occur in any mucosal surface of the body. Hematuria as an isolated or main presenting feature of acute leukemia is rare. We describe two cases of acute leukemia, a 19 year old male with acute lymphoblastic leukemia and a 52 year old male with acute myeloid leukemia, both presenting with gross hematuria. There was no demonstrable leukemic infiltration of the urinary tract on imaging studies. Hematuria in these patients was likely to be due to occult leukemic infiltration of the urinary system, aggravated by thrombocytopenia, as it subsided after starting chemotherapy. Our cases highlight that hematuria should be remembered as a rare presenting feature of acute leukemia

Optimal response to imatinib therapy in a case of chronic myeloid leukemia with a concurrent loss of distal 22q

The hallmark of diagnosing classical chronic myelogenous leukemia (CML) is the identification of Philadelphia (Ph) chromosome (Chr). However, some CML cases show additional structural/numerical chromosomal abnormalities involving either Ph Chr or more frequently other Chrs. Genetic alterations sparing Ph Chr are commonly called “additional chromosomal abnormalities (ACAs)” which have been extensively analyzed in recent large studies. In contrast, the presence of additional genetic abnormalities in Ph Chr has been anecdotally reported with an ambiguity of their impact on treatment response. In our case, we report a newly diagnosed CML patient with the rarest additional chromosomal aberration affecting Ph Chr which has revealed an optimal response over a period of 2 years of follow-up. This report underlines the importance of re-examining CML cases for any ACAs, especially those occurring in Ph Chr, which might be overlooked easily. Moreover, their possible role in disease prognostication should be sought, as well

Massive ascites as a presenting manifestation of chronic lymphocytic leukemia

Ascites is not an uncommon manifestation of certain solid tumors like gastrointestinal malignancies, ovarian cancer and breast cancer. However, it is unusual to encounter ascites in patients with hematological malignancies especially chronic leukemia. The patient described here presented with massive ascites and blood lymphocytosis. Further studies confirmed the diagnosis of chronic lymphocytic leukemia with ascites. The ascitic fluid was exudative, consisting of mature-looking B-lymphocytes, which were morphologically and immunophenotypically similar to peripheral blood and bone marrow cells. The patient was treated with chemotherapy and achieved a good response and diminution of ascitic fluid accumulation

Vanishing bile duct syndrome in a hodgkin′s lymphoma patient with fatal outcome despite lymphoma remission

Vanishing bile duct syndrome (VBDS) is a condition resulting from severe bile duct injury, progressive destruction, and disappearance of intrahepatic bile ducts (ductopenia) leading to cholestasis, biliary cirrhosis, and liver failure. VBDS can be associated with a variety of disorders, including Hodgkin′s lymphoma (HL). We describe a 33-year-old male patient who presented with lymphadenopathy and jaundice, and was diagnosed to have HL. Serum bilirubin worsened progressively despite chemotherapy, with a cholestatic pattern of liver enzymes. Diagnosis of VBDS was established on liver biopsy. Although remission from HL was achieved, the patient died of liver failure. Presence of jaundice in HL patients should raise the possibility of VBDS. This report discusses the difficulties of delivering chemotherapy in patients with liver dysfunction. HL-associated VBDS carries a high mortality but lymphoma remission can be achieved in some patients. Therefore, liver transplantation should be considered early in these patients