Deviation from Normal Values of Leukocyte and Erythroblast Parameters in Complete Blood Count is a Messenger for Platelet Abnormalities

Abstract

Background. Automated blood cell counters have undergone a formidable technological evolution owing to the introduction of new physical principles for cellular analysis and the progressive evolution of software. The results have been an improvement in analytic efficiency and an increase in information provided with new parameters. Aims. In this case report, we imply the incompatibilities between uncorrected leukocyte count (UWBC), leukocyte count (WBC), and erythroblast count (NRBC) might be predictors for morphological and numerical abnormalities of platelets. Methods. A 61 year old male patient had the diagnosis of ''diffuse large B-cell lymphoma'' six years ago and after chemotherapy was still in remission. He was hospitalized for high fever, fatigue, acute renal failure and bibasilar crepitant rales. Complete blood count revealed UWBC 63. 5 x109/l, WBC 22. 1 x109/l, NRBC 21. 4 x109/l, and platelets 197 x109/l. On peripheral blood smear examination we detected 5% neutrophils, 22% band forms, 61% metamyelocytes, 5% myelocytes, 1% promyelocyte, 2% myeloblasts, 2% lymphocytes and 2% eosinophils. We also detected rare erythroblasts and large platelets with profuse platelet clumps. Routine biochemical analysis revealed high fasting glucose, blood urea nitrogen, creatinine, SGOT, alkaline phosphatase, direct and indirect bilirubin, albumin, and lactate dehydrogenase. Erythrocyte sedimentation rate was 100 mm/hour, and serum ferritin was 2 944 ng/ml. High resolution computed tomography of thorax revealed bilateral diffuse infiltrations, nodular opacities, right pleural effusion, and mediastinal lymphadenopathies. Results. Clarithromycin and imipenem/cilastatin were administered for probable diagnosis of pneumonia. Bone marrow examination had myeloid hyperplasia but nothing significant else. No endobronchial mass was detected in bronchoscopy, but mucopurulent secretion was present in right upper and lower lobes. Biopsy reports were non-neoplastic bronchial mucosa epithelium. Sputum, blood, urine cultures, sputum mycobacterial examination and serum galac- tomannan antigen were negative. After general condition, fever, acute renal failure, signs and symptoms relieved, he was discharged. Conclusions.When we subtracted WBC and NRBC from UWBC (=20. 0 x109/l), a significant cell group was composed of big platelets. It is probable that this ratio is higher than calculated. Rare erythroblasts in peripheral blood smear with high NRBC values support the idea of large platelets as cellular origin. In fact, peripheral blood smear revealed large, profuse platelet clumps contradictory to platelet count (Figure 1). We conclude that complete blood counts should be examined carefully, despite the essential role of automation in the modern hematology laboratory, microscopic control of pathologic samples (peripheral blood smear) remains indispensable, so much so that in certain cases, it alone is diagnostic. (Figure Presented).