Diagnostic Accuracy of Immature Platelet Fraction (IPF) to Differentiate Between Thrombocytopenia due to Peripheral Destruction versus Bone Marrow Failure.

OBJECTIVE: To analyse the predictive value of immature platelet fraction (IPF) as an independent diagnostic marker to differentiate between hyperdestructive and hypoproductive thrombocytopenia. STUDY DESIGN: Cross-sectional observational study. Place and Duration of the Study: Armed Forces Institute of Pathology Rawalpindi, from February to July 2022. METHODOLOGY: A total of 164 samples were included in the study by non-probability consecutive sampling. Among these, 80 were obtained from normal individuals serving as control; 43 were obtained from patients having hyperdestructive thrombocytopenia (idiopathic thrombocytopenia, thrombotic thrombocytopenic purpura, disseminated intravascular coagulation); and 41 were obtained from those hypoproductive thrombocytopenia (acute leukaemia, aplastic anaemia, chemotherapy). Sysmex automated haematology analyzer, XN-3000 was used to determine the immature platelet fraction (IPF) of the patients. ROC curves analysis was done to ascertain area under curve. RESULTS: Immature platelet fraction (IPF %) was significantly higher in consumptive / hyperdestructive thrombocytopenia group i.e. median (IQR), 21% (14.4-26.2) as compared to 6.5% (4.6-8.9) in hypoproductive thrombocytopenia, and 2.6% (1.3-4.1) in normal control group (p <0.001). Cut-off value with the highest sensitivity and specificity for IPF vs. normal population was 7.95% with sensitivity of 97.7% and specificity of 86%. CONCLUSION: Immature platelet fraction (IPF of 7.95%) possesses high diagnostic accuracy, sensitivity and specificity for differentiation between hyperdestructive vs. hypoproductive thrombocytopenia. It can be used as a reliable marker to differentiate between the two entities. KEY WORDS: Immature platelet fraction, Thrombocytopenia, Bone marrow failure, Peripheral destruction.

Induction Chemotherapy Response in Childhood Acute Lymphoblastic Leukaemia and its Correlation with Cytogenetic and Molecular Features.

OBJECTIVE: To study the correlation of cytogenetic and molecular abnormalities on induction chemotherapy in childhood acute lymphoblastic leukaemia (ALL). STUDY DESIGN: Analytical study. PLACE AND DURATION OF STUDY: Department of Haematology, Armed Forces Institute of Pathology (AFIP), from March 2021 to August 2021. METHODOLOGY: Patients aged 1-18 years with newly diagnosed acute lymphoblastic leukaemia were inducted. Patients aged less than 1 year and more than 18 years were excluded from the study. The diagnosis was based on morphology, cytochemistry, flow cytometry, and cytogenetic/molecular analysis. Risk stratification was done on the basis of age, TLC, and cytogenetic/molecular defects. The UKALL 2011 protocol was used for treatment with regimen-A for standard risk and regimen-B for high-risk patients. Bone marrow was repeated on day 29 of induction therapy and blast percentage was assessed to establish post-induction remission. Association between cytogenetic / molecular abnormalities and post-induction remission status was analysed using chi-square test. RESULTS: There were total 142 patients with mean age of 6.4 + 3.6 years and a male- to-female ratio of 2.7:1. Immunophenotyping revealed 85.9% cases as B-cell ALL and 14.1% as T-cell ALL. The most frequent cytogenetic and molecular abnormalities were hyperdiploidy (19%), t(9;22)/BCR-ABL1(p190) (10.6%), complex karyotype (5.6%), E2A-PBX1 (8.5%), and TEL-AML1 (4.9%). A total of 127/142 (89.4%) achieved haematological remission after induction therapy with two deaths during induction therapy (1.4%). Post-induction remission rate in patients with favorable cytogenetic/molecular defects was 100% and in children with bad prognostic changes, the rate of remission was 69.2%. Chi-square test showed a significant association between cytogenetic/molecular abnormalities and post-induction remission (p-value <0.001). CONCLUSION: Cytogenetic and molecular abnormalities have a significant association with post-induction remission in children with acute lymphoblastic leukaemia. KEY WORDS: Acute lymphoblastic leukaemia, Cytogenetics, Chemotherapy, Induction, Remission.

Laboratory Evaluation and Pathological Features of Bone Marrow Metastasis in Non-haematological Malignancies.

This study aimed to analyse the diagnostic accuracy of different laboratory parameters that can predict bone marrow metastasis. A cross-sectional analytical study was conducted at the Armed Forces Institute of Pathology (AFIP), Rawalpindi from March 2021 to August 2021. Bone marrow aspirates and biopsy procedures were done on 60 newly diagnosed cases of non-haematological malignancies as part of staging. Laboratory parameters noted for the study included peripheral blood smear findings, serum lactate dehydrogenase (LDH), radiological findings, and bone marrow aspirate/trephine biopsy results. Bone marrow metastasis was seen in 21/60 patients. The most common malignancies with bone marrow involvement were retinoblastoma and neuroblastoma. Laboratory findings showed no significant statistical difference in mean haemoglobin and total leukocyte count between cases and controls. Positive cases had a mean platelet count of 261.7 x 109/L and mean LDH of 750.1 U/L (p <0.05) for both parameters. ROC analysis showed the area under the curve (AUC) for LDH to be 0.969 (highly significant) showing a strong predictive value of LDH. Positive radiological findings were detected in only one case with bone marrow metastasis. The elevated level of serum LDH is not only cost-effective but also has high diagnostic accuracy to predict bone marrow metastasis. Key Words: Bone marrow, Biochemical, Lactate dehydrogenase, Metastasis, Non-haematological malignancies.