METHODS: The Filipino β-deletion was identified using gap-polymerase chain reaction (PCR) in the parents of transfusion dependent β-thalassaemia patients who were homozygous for the Filipino β-deletion in the indigenous population of Sabah, Malaysia. Hb subtypes were quantified on the BioRad Variant II Hb analyser. Concurrent α-thalassaemia was identified by multiplex gap-PCR for deletions and amplification refractory mutation system (ARMS)-PCR for non-deletional mutations.
RESULTS: The mean HbA2 level for Filipino β-thalassaemia trait was 5.9 ± 0.47 and with coinheritance of α-thalassaemia was 6.3 ± 0.44 (-α heterozygous) and 6.7 ± 0.36 (-α homozygous). The HbA2 levels were all >4% in keeping with the findings of classical β-thalassaemia trait and significantly higher than levels seen in non-deletional forms of β-thalassaemia.
CONCLUSION: The HbA2 level measured on the BioRad Variant II Hb analyser was lower than the level in the first description of the Filipino β-thalassaemia. β-thalassaemia trait with coinheritance of α-thalassaemia (-α) is associated with significantly higher HbA2 level.
METHODS: Haemoglobin variants were identified by HbA1c analysis in 93 of 3522 samples sent to our laboratory in a period of 1 month. Haemoglobin analysis identified HbE trait in 81 of 93 samples. To determine the influence of HbE trait on HbA1c analysis by Variant II Tubo 2.0, boronate affinity high performance liquid chromatography (HPLC) method (Primus PDQ) was used as the comparison method. Two stage linear regression analysis, Bland Altman plot and Deming regression analysis were performed to analyse whether the presence of HbE trait produced a statistically significant difference in the results. The total allowable error for HbA1c by the Royal Australasian College of Pathologists (RCPA) external quality assurance is 5%. Hence clinically significant difference is more than 5% at the medical decision level of 6% and 9%.
RESULTS: Statistically and clinically significant higher results were observed in Variant II Turbo 2.0 due to the presence of HbE trait. A positive bias of ∼10% was observed at the medical decision levels.
CONCLUSION: Laboratories should be cautious when evaluating HbA1c results in the presence of haemoglobin variants.
METHODS: Fifty follicular lymphoma cases were retrieved from the files of the Department of Pathology, University of Malaya Medical Centre (UMMC). Nested PCR amplification of MBR/JH and mcr/JH was performed in these cases, and those cases that did not demonstrate the translocation were subjected to FISH analysis.
RESULTS: Thirty cases (60%) had t(14;18) translocation detected by PCR, 25 (50%) had breakpoint with MBR and five (10%) involved mcr. Twenty cases without detectable t(14;18) translocation by PCR were analysed by FISH. Eleven cases were successfully probed, and four of them showed positive translocation signal.
CONCLUSIONS: The combination of PCR and FISH analysis on paraffin tissue sections for the detection of t(14;18) translocation increases the sensitivity of detection from 60 to 68%. Problems encountered in our FISH analysis on tissue sections impose certain limitations in using this technique for retrospective screening of large number of samples. Therefore, we suggested the application of PCR as the first screening tool on retrospective archival materials, followed by FISH on those PCR-negative cases.
METHODS: Surgical samples from seven patients with a total of 17 sequential biopsies were retrieved for the study of p53 gene expression using immunohistochemical stain, and gene status by PCR-SSCP for exons 5-8. The tumours were graded according to the WHO classification criteria. P53 was distinctly over-expressed in five transformed higher grade biopsies, and all except one showed electrophoretic mobility shift in PCR-SSCP analysis. Sequencing analysis revealed single nucleotide substitutions in three of four of these high-grade transformed cases with band shift (75%), whereas some other studies reported a lower frequency of 25-30%, and mobility shift result was found to correlate with P53 expression. Lower grade tumours without P53 over-expression did not demonstrate band shift, and sequencing analysis did not reveal mutations.
CONCLUSIONS: We demonstrated the feasibility of adopting PCR-SSCP for screening of p53 mutations in archival tissue samples in this study, and there is a strong correlation of p53 gene over-expression and mutation events in high-grade transformed tumours.
METHOD: Blood samples were obtained from 20 healthy blood donors, 30 RA patients who presented with anaemia and 30 patients who had pure iron deficiency anaemia (IDA). The samples were analysed for full blood count, iron, ferritin, transferrin, soluble transferrin receptor and prohepcidin.
RESULTS: The mean prohepcidin level in the control subjects was 256 microg/L. The prohepcidin level was significantly lower in IDA patients (100 microg/L; p < 0.0001) but not significantly different from that of control in RA patients (250 microg/L; p > 0.05). Higher serum soluble transferrin receptor (sTfR) levels were observed in IDA (p < 0.0001) but not in RA compared with that of control (p > 0.05). RA patients were divided into iron depleted and iron repleted subgroups based on the ferritin level. Prohepcidin in the iron depleted group was significantly lower than the iron repleted group and the control (p < 0.0001) and higher levels were observed in the iron repleted group (p < 0.01). sTfR levels in the iron depleted group were significantly higher than the control and the iron repleted patients (p < 0.001). In the iron repleted group, sTfR level was not statistically different from that of control (p > 0.05).
CONCLUSION: Serum prohepcidin is clearly reduced in uncomplicated iron deficiency anaemia. The reduced prohepcidin levels in the iron depleted RA patients suggests that there may be conflicting signals regulating hepcidin production in RA patients. In RA patients who have reduced hepcidin in the iron depleted group (ferritin <60 microg/L) where sTfR levels are increased suggests that these patients are iron deficient. Further studies with a larger cohort of patients are required to substantiate this point.
METHODS: Paraffin-embedded tissue from 38 lymphomas (17 Hodgkin's, 14 Burkitt's, four T cell and 3 B cell non-Hodgkin's lymphomas) and 14 nasopharyngeal carcinomas (NPC) were studied, with 12 reactive lymph nodes and tonsils as normal control. EBER in situ hybridisation was performed to confirm EBV association in the tumour cells. A nested polymerase chain reaction (PCR) protocol was employed using two pairs of consensus primers which flanked a 105-bp deletion in the type A virus. U2 region encoding for EBNA-2 was chosen as the target of amplification, with cell lines B95.8 and AG876 serving as positive controls for types A and B virus, respectively.
RESULTS: All cases showed presence of type A virus, consistently detected with nested PCR protocol but not with single step PCR. There was no type B virus or mix infections detected.
CONCLUSIONS: Nested PCR technique has successfully increased the sensitivity of EBV subtype detection, and type A virus is the prevalent strain associated with human diseases in Malaysia.
METHODS: A total of 66 cHL cases were retrieved from the archives. Expressions of CD30, CD40, CD95 and proliferation by Ki-67 expression were detected with an immunohistochemical staining method. Apoptosis index was assessed by in situ TUNEL staining technique on 30 randomly selected cases and the presence of EBV was determined by EBER in situ hybridisation.
RESULTS: Expression of CD30, CD40 and CD95 in the H/RS cells was observed in a high proportion of the cases (100, 93.9, 90.5%, respectively). There was no significant association or correlation of the expression of these molecules with the presence of EBV. Expression of CD40 was associated with expression of the proliferation marker Ki-67 (P=0.044), whereas strong (intermediate and high) expression of CD30 showed a significant correlation with proliferation in the EBV-negative cases only (P=0.025). No correlation was observed for the expression of CD30 and CD40 with apoptosis of the H/RS cells. The childhood cases showed weaker CD95 expression in the H/RS cells than the adult cases, and the expression of CD95 was weaker than that of CD40 in the childhood group.
CONCLUSIONS: Our results showed that CD30, CD40 and CD95 are highly expressed in the H/RS cells of the majority of cases of cHL. The expression patterns seem to be independent of EBV and do not correlate with apoptosis of the H/RS cells.
METHODS: Using a panel of antibodies to CD10, Bcl-6, MUM1 and CD138, consecutive cases of primary UAT DLBCL were stratified into subgroups of germinal centre B-cell-like (GCB) and non-GCB, phenotype profile patterns A, B and C, as proposed by Hans et al. and Chang et al., respectively. EBER in situ hybridisation technique was applied for the detection of EBV in the tumours.
RESULTS: In this series of 32 cases of UAT DLBCL, 34% (11/32) were GCB, and 66% (21/32) were non-GCB types; 59% (19/32) had combined patterns A and B, and 41% (13/32) had pattern C. Statistical analysis revealed no significant difference in the occurrence of these prognostic subgroups in the UAT when compared with series of de novo DLBCL from all sites. There was also no site difference in phenotype protein expressions, with the exception of MUM1. EBER in situ hybridisation stain demonstrated only one EBV infected case.
CONCLUSIONS: Prognostic subgroup distribution of UAT DLBCL is similar to de novo DLBCL from all sites, and EBV association is very infrequent.