Pancytopenia: A multidisciplinary assessment of hemato-etiological and clinical spectrum in a tertiary care hospital

Background : The causes of pancytopenia range from simple, completely treatable diseases to serious life-threatening conditions. A thorough evaluation of these cases is mandatory as it would benefit the patients to receive appropriate treatment. Objectives: Evaluation of etio-hematological and clinical spectrum of pancytopenia. Settings and Design: A prospective study of two years (Jan 2016 -December 2017) was conducted on pancytopenic patients, attending Navodaya Medical College, Hospital and Research Centre, Raichur, Karnataka. Material and Methods : Etio- hematological and clinical evaluation was done considering the relevant biochemical and serological investigations. Results: A total number of 1368 of cases were diagnosed as pancytopenia. The patients’ age ranged from 19 to 68 years and M: F ratio was 2.1:1. Most frequent clinical symptom was generalized weakness (90%) and least was bony pain (2%). Peripheral smear examination revealed predominantly macrocytic blood picture (47.9%). Bone marrow aspiration was performed in 444 cases (32.4%), among which Megaloblastic anaemia (Exclusive and Combined with iron deficiency anemia) was the commonest (52.7%). Etiologies of pancytopenia in decreasing order of frequency included Megaloblastic anemia {935 cases (68.4%) – Exclusive type (713 cases; 52.2%) and Combined with iron deficiency anemia (222 cases;16.2%)z, followed by Dengue fever (141 cases;10.3%), Hypoplastic/Aplastic anemia [106 cases;7.8% (Drug induced - 4 cases; 0.2%)], Septicemia (60 cases;4.5%), Leukemia (46 cases;3.25%), Chronic malaria (46 cases ;3.25%) and Myelodysplastic syndrome (34 cases; 2.5%). Conclusion : Keeping in mind varied etiologies of pancytopenia, thorough diagnostic evaluation is required to achieve better clinical outcome.


Introduction
Pancytopenia is an important commonly encountered hematological condition characterized by a triad of findings that results from a number of disease processes -primarily or secondarily involving the bone marrow leading to decrease in all three lineages of blood cells [1]. The underlying mechanis ms other than decrease in hematopoietic cell production are marrow rep lacement by abnormal cells, suppression of marro w growth and differentiation, ineffective hematopoiesis, defective stem cell formation, antibody mediated sequestration, destruction and trapping of cells in an overactive reticuloendothelial system [2,3]. Et iologies of this condition can be due to common diseases like nutritional anemias, drug induced myelosuppression and infections such as malaria, kala azar or dengue, to life threatening conditions like aplasia, myelodysplasias and leukemias [4]. The prevalence and risk factors vary in different geographical areas depending on life style, nutritional status and exposure to chemical or biological myelotoxins. A wide range of clinical and hematological manifestations are exhibited due to broad spectrum of etiologies of pancytopenia.
An early detection of underlying pathology helps in timely diagnosis and therapeutic intervention favoring a better clinical outcome [5,6]. Hence, this study was thus undertaken to evaluate cases of pancytopenia in Raichur, Karnataka state.

Objectives
1. Evaluation of hemato-etiological and 2. Clinical spectrum of cases of pancytopenia Sampling methods and sample collecti on-A thorough clin ical h istory was taken along with general and systemic examination of patients. Various hematological and serological parameters were analyzed and are as follows: i) Hematology-Using semi auto mated hematology analyzer Pentra ES 60, CBC (Hb%, red cell indices, total and differential leucocyte count, platelet count) along with grading of anemia, leucopenia and thrombocytopenia was done, while peripheral smear study by Leishman stained blood smears. Features observed in the latter were: RBC-Anisopoikilocytosis, nucleated RBCs and morphological type of anemia; WBC -Hypersegmented neutrophils, toxic granulat ion, relative ly mphocytosis and immature cells/ blasts; Platelets-Normal, small & giant forms and Screening for hemoparasites. Reticu locyte count was estimated on New Methylene Blue stained smears. Bone marrow aspiration was performed wherever feasib le after obtaining written consent from the patients. The procedure was done using Salah's needle, the aspirate obtained was spread on the glass slides which were subsequently stained by Leishman's & Giemsa stain and observed for cellu larity, myelo id: erythroid (M :E) ratio, erythropoiesis, myelopoiesis, megakaryopoiesis, ly mphocytes, plasma cells, bacteria/parasites/ fungal elements, blast cells and other infiltrat ive disorders. Blasts were categorised as per WHO and FAB classification criteria. Special stains with Myeloperoxidase (MPO) and Periodic acid Schiff reagent (PAS) were done on peripheral smears & bone marrow smears, wherever required.
ii) Relevant biochemical investigations included serum iron, ferrit in, Vitamin B12 & folate studies and c-reactive protein (CRP).
iii) Sero logical tests with Rapid Card Malaria test and Dengue card test (NS1, IgM and IgG) were performed in suspected cases.
The toxic granulation in neutrophils and shift to left in myelo id series were noted in septicemia cases (65%), and hypersegmented neutrophils were observed in cases with megaloblastic anemia (62%). Presence of blasts was predominant in leukemia (46 cases; 57.5%) compared to MDS (34 cases; 42.5%). Immature ly mphoid cells were most commonly found in cases of aplastic anemia (95%), fo llo wed by megaloblastic anemia (22%) and MDS (12%). Peripheral smear study showed classical features of blasts of respective leukemia and were confirmed using special stains. Giant forms of platelets were mostly seen in patients with nutritional anemia (25%), co mpared to septicemia (8%) and dengue cases (6%), while smaller forms were observed in aplastic anemia and rest other cases showed normal platelets.
iii) Ret iculocyte count: Increased count was observed in malaria, nutrit ional anemia and septicemic cases, whereas those with aplastic anemia and MDS showed reduced reticulocyte count.
iv) Bone marro w study: Varying degrees of dysmyelopoiesis was observed and was most predominant in MDS (98%) followed by megaloblastic anemia (86%).

Discussion
The demographic pattern of pancytopenia varies all over the world possibly due to the differences in methodology, stringent diagnostic criteria, duration of study, geographic distribution, genetic differences, age distribution, nutritional status, infections and exposure to myeloto xic agents [7].  [4,6,9]. Majority of the cases presented with weakness/ fatigue (90%) followed by pallor (66%) and dyspnoea (50%), wh ile a s mall proportion of patients had bleeding manifestations (6%). Sympto ms attributable to anemia or thrombocytopenia were more co mmon in this study than those due to leucopenia. Similar observation was documented by Anita Javalgi et al [6]. Presentation of organomegaly {splenomegaly (21%), hepatomegaly (9%) and ly mphadenopathy (3%)} and bony tenderness (2%) was comparable to those of Gayatri   The variations in the red cell indices (MCV, M CH and MCHC) were in accordance with the study of Nazish Shinwari et al [12].

Original Research Article
The mo rphological features of bone marrow were co mparable with other studies. (Refer Table 6).  [11]. The incidence of aplastic/ hypoplastic anemia accordi ng to the literature varies from 10% to 52.7% [4,11]. The present study reported the same as the third common cause (7.7%), whereas Gayatri et al (18.26%) and Khunger et al (14%) reported as second common etiology [4,10]. Aplastic/ hypoplastic anemia may be due to triggering of aberrant immune response by viral infections, exposure to chemicals and drugs or endogenous antigens generated by genetically altered bone marrow cells, leading to active destruction of blood forming cells by lymphocytes [7,10]. Drug induced aplastic anemia is common ly seen in cases receiving therapy for rheumatoid arthritis, hyperthyroid conditions, tuberculosis, convulsive disorders and various inflammatory disorders. The outcome depends on:

Eti ologies
i) Dose and duration of exposure and ii) Susceptibility or idiosyncracy to the myelotoxin.
These usually cause mild reversible marro w suppression, but may occasionally progress to more severe damage [16]. The cases of MDS showed splenomegaly and hepatomegaly more frequently in the study of Khunger et al (75%; 50%) when compared to present study (58.8%; 23.5%). Ly mphadenopathy was not seen in this study as well as the authors' studies.
Cases of malaria had splenomegaly more co mmonly in the studies of Khunger et al (100%) and Gayatri et al (100%) compared to this study (65.2%), whereas hepatomegaly and ly mphadenopathy was not seen in either of the said studies [4,9].
Among the frequent etiologies of pancytopenia in the world scenario, aplastic anemia is documented to be the commonest especially in countries like Israel, Europe, Bangladesh and India. Myelodysplastic syndrome and neoplastic diseases are the next common ones in Israel & Europe, chronic malaria and kala azar in Bangladesh; while on the contrary, it was megaloblastic anemia in India [5].

Conclusion
Keeping in mind the probable etiologies and large proportion of pancytopenia being reversible, a thorough evaluati on is warranted to i denti fy the underly ing pathology at the earliest, thus guiding the clinicians to implement preventi ve strategies and hel p the patients in achievi ng better clinical outcome.

Names of Authors
What this study add to existing knowledge-Based on assimilation of data fro m previous studies and current research, there exists an overlap of certain clinico-hematological find ings. As etiological spectrum of pancytopenia is varied and confounds the pathologists and clinicians, routine along with bone marro w and etiological based laboratory evaluation is warranted. The frequency of this hematological condition Pancytopenia, is on the rise and hence needs global attention.
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