Hairy cell leukemia (HCL) is characterized by pancytopenia and usually associated with massive splenomegaly, however the same may not be true in the clinical settings. Here we report four cases of HCL and all of them were without the classical clinical feature of splenomegaly. This is an observational study conducted between January 2013 to March 2014 where we could diagnose ten cases of HCL in Department of Hematology, All India Institute of Medical Sciences, New Delhi. Of these, four cases attracted attention because of absence of classical clinical features of HCL. Of the four cases, three presented with weakness/fatigability while fourth patient presented with recurrent respiratory tract infection. Surprising finding in these cases was absence of splenomegaly, both clinically and on imaging which demerit the suspicion of HCL clinically. All four had bi/pancytopenia and bone marrow examination coupled with immunophenotypic analysis confirmed the diagnosis of HCL. Three patients received chemotherapy with cladribine and achieved complete hematological remission. One patient did not receive chemotherapy due to poor general condition and was subsequently lost to follow up. To conclude, HCL can and do present without splenomegaly and this should not restrain one from suspecting HCL based on histomorphology which needs to be further confirmed by ancillary techniques. This finding in our series could be because these cases were picked early in their natural course of the disease. A high index of suspicion is essential for diagnosing and appropriately managing such cases.

Introduction:Hairy cell leukemia is a rare chronic B-cell disorder that follows an indolent but progressive course. This disorder is characterized by pancytopenia, splenomegaly, bone marrow fibrosis and the presence of atypical lymphoid cells with hairy projections in peripheral blood, bone marrow and spleen. Treatment is mainly with nucleoside analog cladribine, which induces complete remission in up to 85% cases.Materials and Methods:This is a retrospective analysis of Hairy cell Leukemia cases diagnosed and treated in the Department of Hematology, All India Institute of Medical Sciences, New Delhi between 2002 and 2013. Various parameters such as clinical features, laboratory parameters including complete blood cell count, bone marrow findings, cytochemistry, immunophenotyping by flowcytometry or immunohistochemistry, treatment protocol and complications secondary to treatment and relapse were reviewed.Results:A total of 35 cases were diagnosed during this period of 12 years of which 27 received cladribine and went in to remission. Median follow-up duration was 26 months. 5 (18%) cases had a relapse and all relapsed cases achieved second remission with cladribine; however, there was no case of second malignancy in our cohort.Conclusion:Cladribine has emerged as the treatment of choice for hairy cell leukemia given that the overwhelming majority of patients achieve long-lasting complete remissions. Upon relapse, these patients could be successfully salvaged with cladribine retreatment.

Children with Down syndrome (DS) present with a spectrum of hematolymphoid malignancies ranging from transient myeloproliferative disorder (TMD) which regress spontaneously to frank acute leukemia of both myeloid and lymphoid lineage. Here we present a series of three cases with different manifestation in DS. Three cases of DS presented with TMD, acute myeloid leukemia (AML-M2) and acute megakaryoblastic leukemia (AMKL), respectively. This case series displays the spectrum of hematological manifestations in children with DS. Although TMD and AMKL are strongly associated with DS, other AML subtypes can also be seen in such patients.

Our results suggest that FC-OFT could be the better screening test for HS cases in developing countries if flow cytometer is available.

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal hematopoietic stem cell disorder with its protean clinical manifestations. This is due to partial or complete absence of 'glycophosphatidyl-inositol-anchor proteins' (GPI-AP). The main aim of this review is to highlight various diagnostic modalities available, basic principle of each test and recent advances in the diagnosis of PNH. Recently among various tests available, the flow cytometry has become 'the gold standard' for PNH testing. In order to overcome the difficulties encountered by the testing and research laboratories throughout the world, International Clinical Cytometry Society has come up with guidelines regarding the indications for testing, protocol for sample collection, processing, panel of antibodies as well as gating strategies to be used, how to interpret the test and reporting format to be used. It is essential to test at least two GPI-linked markers on at least two different lineages particularly on red cells and granulocytes/monocytes. The fluorescent aerolysin combined with other monoclonal antibodies in multicolour flow cytometry offered an improved assay not only for diagnosis but also for monitoring of PNH clones. It is equally important to diagnose this rare entity with high index of suspicion.