Normal Peripheral Blood Smear Research Articles

Development of Consensus Guidelines for Hematology Fellow Competency in Peripheral Blood Smear Review Utilizing Nominal Group Technique

INTRODUCTION: Graduate medical education (GME) training in hematology in the United States is accredited by the Accreditation Council for Graduate Medical Education (ACGME). Trainees provide patient care that requires manual review and interpretation of peripheral blood smears (PBS). The ACGME milestones were developed with significant input from the American Society of Hematology (ASH) and mandate fellow competency in the interpretation of peripheral blood smears. However, there are currently no publications that define competency or propose consensus recommendations (CRs) for PBS review. The primary aim of this study was to establish CRs on PBS review with a focus at the GME level. METHODS: Nominal group technique (NGT) and constructivist grounded theory (CGT) were selected given the lack of existing published theory and consensus on the methodology of PBS review or other analogous visuospatial skills within GME. A convenience sample of hematologists with expertise in training and assessing fellows was recruited through the ASH Medical Educators Institute. Goal accrual was 5-10 hematologists. Participants were required to regularly review PBSs as part of their clinical practice and attend two 1-hour virtual focus group sessions. The facilitator guide for session 1 was developed a priori to prompt open discussion on PBS review. Dialogue was transcribed and organized into thematic concepts through inductive coding. Data from session 1 were analyzed using a mixed methods approach and were used to develop a facilitator guide for session 2. Draft CRs were created using CGT. Weak and strong consensus were pre-specified as 50 - 69%, and >70% agreement, respectively. CRs underwent iterative review which would continue for a pre-specified minimum of 2, but no more than 3 rounds. RESULTS: Eight academic hematologists (5 men, 3 women) enrolled in the focus group (Table 1). Duration of clinical practice ranged from 5 to 33 years. Clinical focus spanned classical and malignant hematologic conditions. Half had formally instructed trainees in course work on PBS morphology. All routinely worked with fellows. CRs were generated through CGT. Three rounds of review occurred. Participants provided a statement of agree vs. disagree and offered qualitative suggestions for each statement in which they disagreed. Response rates per round were 87.5%, 87.5%, and 100%. The most commonly identified themes included recognition of morphology suggestive of thrombotic microangiopathies and distinguishing between malignant vs. benign white blood cells (WBC), specifically as it pertains to acute leukemias. Strong consensus was reached on multiple aspects of PBS education, including curricular considerations, method of review, and morphology (Table 2). All agreed that trainees should learn PBS review through a systematic approach, although some agreed that this systematic approach is not always used in clinical practice. The group agreed that trainees should be educated through PBS review of patients under their clinical care as well as through formal slide "libraries". Many discussed the changing landscape of PBS education with the advent of digital microscopy, and formed strong consensus that trainees should understand the benefits and limitations of digital microscopy. Group discussion largely focused on disorders of WBCs and red blood cells (RBC) (43% and 48% of all coded statements respectively). Most discussion focused on disorders in which prompt recognition was imperative to avert significant patient morbidity or mortality. However, all agreed that trainees must also be competent in the identification of common conditions, regardless of the degree of clinical importance, including normal peripheral blood smear morphology. The group was unable to reach consensus on how to balance these competing philosophies. CONCLUSIONS: A formal theory of PBS education was systematically developed using CGT. Experts were able to form strong CRs on almost every aspect of PBS review at the GME level. FUTURE DIRECTIONS: We propose that these guidelines serve as a template for future research and curricular development for both PBS review and other visuospatial tasks in medical education. This framework can also be used by organizations, such as ACGME and ASH, when formally reviewing and codifying guidelines on PBS review. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Acute Myeloid Leukaemia Presenting as B12 Vitamin Deficiency When Multiple Horses Become a Zebra.

Vitamin B12 is a common aetiology of pancytopenia and is usually caused by gastric malabsorption.When supplementation does not correct the haematological deficit, central causes must be considered. Acute myeloid leukaemia is one possibility, but causes peripheral blood smear abnormalities in almost all patients. Diagnosis should include lumbar puncture and a thorough search for the aetiology; treatment is directed towards the aetiology.Neoplastic diseases should be always excluded when correction of the deficit does not resolve cytopenias.

Splenic auto-transplantation after splenectomy for trauma: evaluation of a new technique.

Splenic autotransplantation is a promising method to recover splenic functions after traumatic splenectomy. However, it is associated with several postoperative complications, such as subphrenic abscess, intestinal obstruction and torsion of the omentum with necrosis of the implanted splenic tissues. Therefore, the aim of this study is to evaluate a new splenic autotransplantation technique that could overcome those complications. A single segment of the spleen was implanted inside a pedunculated omental pouch and fixed in the native site of the spleen in 15 patients who underwent splenectomy for abdominal trauma. This group of patients was compared with the next 17 patients who underwent splenectomy alone. Additionally, splenic functions of the patient and control groups were evaluated 3months using peripheral blood smear [the presence of Howell-Jolly (HJ) bodies] and abdominal contrast-enhanced computed tomography (CECT). All patients who underwent splenic autotransplantation showed evidence of a well-vascularised splenic tissue on CECT and normal peripheral blood smear without HJ bodies 3months postoperatively. No postoperative complications related to splenic autotransplantation were observed, and platelet count after 3months was significantly higher in patients who underwent splenectomy only (p=0.04). Splenic autotransplantation using the aforementioned technique could restore splenic functions with minimum postoperative complications related to the procedure.

Case report of a novel homozygous variant in a Saudi patient with alpha mannosidosis

Background: Alpha-mannosidosis [Online Mendelian Inheritance in Man (OMIM): 248500] is an autosomal recessive disorder due to a deficiency of the lysosomal enzyme alpha-mannosidase. It is an ultra-orphan disease. In this paper, we report a case of alpha-mannosidosis in a Saudi boy of consanguineous parents, who was referred to our hospital to be worked up for possible mucopolysaccharidosis. Case Presentation: The patient was presented with dysmorphic features, global developmental delay, hearing defect, and recurrent respiratory tract infections. On examination, he had short stature, a short neck, cataracts, hearing impairment, chest deformity, hepatomegaly, umbilical hernia, right inguinal hernia, and two Mongolian spots in the back. He had normal peripheral blood smear: urinary oligosaccharide and dry blood spot for mucopolysaccharide enzyme assay founded to be negative. Definitive diagnosis was performed by directly sequencing the MAN2B1 gene of the peripheral blood leukocytes. It showed a homozygous variant c.1065delC; p.Ala356fs*7 (NM_001173498.1) as likely pathogenic. Conclusion: We report a novel variant mutation in MAN2B1 gene mutation. Also, to the best of authors' knowledge, this is the first reported case of alpha-mannosidosis in a Saudi patient.

English

BACKGROUND Thrombosis associated with thrombocytopenia is a vascular paradox which we seldom encounter in our clinical practice. We hereby describe four real world clinical situations and their therapeutic management. Since there are no guidelines regarding this subset, most of the treatment is based on few anecdotal reports and consensus data. Hence, we have reviewed the literature to throw light on some pertinent clinically relevant questions. Our objective is to describe and discuss the probable reasons of vascular paradox and its management. METHODS It is a descriptive study of four cases collected over one-year period including patients of thrombosis with thrombocytopenia. RESULTS In the first case, the patient had pulmonary embolism as a presenting manifestation of leukaemia. Only 5 % cases of AML-M3 sub type acute promyelocytic leukaemia present with normal peripheral blood smear. Patient had thrombocytopenia with deep vein thrombosis and pulmonary embolism. In the second case, secondary antiphospholipid antibody syndrome (APLS) presented with ilio-femoral deep vein thrombosis associated with thrombocytopenia and bleeding tendency. In the third case, antiphospholipid antibody syndrome with thrombocytopenia was associated with severe pulmonary hypertension and deep vein thrombosis. In the fourth case, patient presented with non-ST elevation myocardial infarction (NSTEMI) with thrombocytopenia. He was diagnosed with idiopathic thrombocytopenic purpura. He had angiographic evidence of critical triple vessel disease. He was treated with coronary bypass surgery after initiating treatment with oral eltrombopag and steroids. CONCLUSIONS We have highlighted four clinical situations ranging from frank malignancy to pure vascular pathology, where we have encountered and tackled the vascular paradox of ‘thrombosis and thrombocytopenia’ and reviewed the literature pertaining to these case scenarios. KEYWORDS Thrombosis with Thrombocytopenia, APLS, AML-M3, Pulmonary Hypertension, ITP

WBCaps: A Capsule Architecture-based Classification Model Designed for White Blood Cells Identification.

This pilot study presented a capsule architecture-based classification model named WBCaps to automatically recognize the five types of white blood cells (WBC) from normal peripheral blood smears. The entire WBCs identification workflow including two sections were also reported here. The first section automatically located the WBCs from the whole slice of blood smears through a three-step image segmentation method including color normalization, color deconvolution and cell extraction. In the second section, the extracted cells were fed into WBCaps, which was a network cascaded by traditional convolutional layer, primary capsule layer and representation capsule layer, to generate the type prediction. We employed 3-fold cross validation to validate the proposed WBCs identification method on a small clinical dataset and yielded precision 0.99, recall 0.99 and F1-score 0.99. The result outperformed that of ResNet (precision 0.97, recall 0.97, F1-score 0.97) and VGG (precision 0.97, recall 0.97, F1-score 0.98). The proposed model could be a promising clinical tool for hematology analyzer to facilitate the cytological and morphological examination.

Detection of acute lymphoblastic leukemia using image segmentation and data mining algorithms.

Blood is composed of white blood cells, red blood cells, and platelets. Segmentation of the blood smear cells and extraction of features of the cells is essential in the field of medicine. Acute lymphoblastic leukemia is a form of blood cancer caused due to the abnormal increase in the production of immature white blood cells in the bone marrow. It mostly affects the children below 5years and adults above 50years of age. Due to the late diagnosis and cost of the devices used for the determination, the mortality rate has increased drastically. Flow cytometry technique that performs automated counting fails to identify the abnormal cells. Manual recount performed using hemocytometer are prone to errors and are imprecise. The proposed work aims to survey different computer-aided system techniques used to segment the blood smear image. The primary objective here is to derive knowledge from the different methodologies used for extracting features from white blood cells and develop a system that would accurately segment the blood smear image by overcoming the drawbacks of the previous works. The objective mentioned above is achieved in two ways. Firstly, a novel algorithm is developed to segment the nucleus and cytoplasm of white blood cell. Secondly, a model is built to extract the features and train the model. The different supervised classifiers are compared, and the one with the highest accuracy is used for the classification. Six hundred images are used in the experimentation. InfoGainAttributeEval and the Ranker Search method are used to achieve the feature selection which in turn helps in improvising the classifier performance. The result shows the classification of the acute lymphoblastic leukemia into its three respective categories namely: ALL-L1, ALL-L2, ALL-L3. The model can differentiate between a normal peripheral blood smear and an abnormal blood smear. The extracted feature values of a cancerous cell and a normal cell are also shown. The performance of the model is evaluated using the test images stained with various stains. The proposed algorithm achieved an overall accuracy of 98.6%. The promising results show that it can be used as a diagnostic tool by the pathologists. Graphical abstract.

Which common test should be used to assess spleen autotransplant effect?

Historically, total splenectomy was the only choice of treatment for traumatic splenic injuries. However, nonoperative management and spleen-preserving surgical techniques are preferred in modern medicine. In some situations in which the surgeon has to perform splenectomy, spleen autotransplant may preserve the splenic function. Selecting the best method for evaluating the splenic autotransplant effect has been debated for several years. In this study, we compared three common tests in evaluating the implanted spleen function. Participants included 10 patients who were candidates for laparotomy and splenectomy. After performing splenectomy, we implanted five pieces of the spleen in the greater omentum of each patient. After 3 months, the implanted spleen function was evaluated by nuclear red blood cell (RBC) scan, serum immunoglobulin (Ig) M level, and presence of Howell-Jolly (HJ) bodies in the peripheral blood smear. All patients had normal peripheral blood smear. The IgM level was lower than normal in one patient, and scintigraphy did not demonstrate the transplanted spleen in another patient. All these tests may have comparable results, but because of availability and low cost of peripheral blood smear, which is also easily performed, it can be considered as the first option to evaluate the implanted spleen function.

A Case of Pancytopenia with Hyperthyroidism

There has been an increase in the number of reports of atypical manifestations of Graves’ disease (GD), such as jaundice, anemia, thrombocytopenia and leukopenia. Pancytopenia also rarely occurs in GD. In this paper, a case of pancytopenia with GD that was successfully treated with an anti-thyroid drug is reported. In this case, a 69-year-old woman showed pancytopenia with a normal peripheral blood smear, bone marrow aspiration smear and bone marrow biopsy. Her thyroid function test and thyroid scintigraphy confirmed her hyperthyroid status. Her laboratory abnormality and clinical condition improved after she was treated with an anti-thyroid drug. This is a rare case of pancytopenia associated with GD.

Falsely Reported Malaria Parasites in Otherwise Normal Peripheral Blood Smears

In Iraq the diagnosis of malaria relies only on detection of the parasite in thick blood film and later on determination of its species using thin blood film. Almost always there are no other auxiliary tests. Moreover, the incidence of malaria in Iraq nowadays is very low that no routine training for its morphological detection is available. In Iraq the incidence of false positive reporting of the presence of malaria parasites in peripheral blood smear of normal people or febrile patients as part of routine diagnosis process or as a quality control check for the hematology laboratory morphology work is a well known phenomenon but no real statistics are available for the local work. However, problems with this false positive diagnosis of malaria are not only confined to Iraq, as there are 6.0% of 2,744 laboratory reported malaria parasites when none were present by United Kingdom National External Quality Assessment Scheme (NEQAS) surveys [1]. Moreover, as far as we know no explanation can be found in the published literature. Myeloid cell cytoplasm fragments are perfectly normal findings that have very variable shapes, sizes and granular contents without a specific clinical significance. It is seen mainly in bone marrow smears and less frequently in peripheral blood smears. Unfortunately, in many occasions these fragments were erroneously mixed with the morphological diagnosis of malaria by junior hematologists who are usually performing the routine work [2]. This can be an important explanation for the falsely reported malaria parasites in otherwise normal peripheral blood smears.

Nonleukemic granulocytic sarcoma of kidney with mixed phenotype blasts: A diagnostic dilemma

Granulocytic sarcoma (GS) usually presents concomitantly with or after the onset of acute myeloid leukemia, blastic phase of chronic myeloid leukemia (CML), or myelodysplastic syndromes. Rarely, it may present even before the onset of overt leukemia and when so, it is often misdiagnosed. We are reporting a case of GS of kidney presenting as an isolated renal mass with normal laboratory investigations including a normal peripheral blood smear. It was initially misdiagnosed as lymphoma as the blasts, in addition to the morphological similarity with lymphoma cells, also showed positive immunohistochemistry for B cell markers. Based on further investigations including immunophenotyping and cytogenetic studies, a final diagnosis of CML-blast crisis (mixed phenotype) presenting initially as GS was made. To the best of our knowledge, this is the first antemortem report of nonleukemic GS presenting as kidney mass that later on progressed to CML-blast crisis with mixed phenotype blasts.

The effect of antiepileptic drugs on vitamin B12 metabolism

The effects of antiepileptic drugs (AED) on the serum concentration of vitamin B12, folic acid and homocysteine (HMC), and erythrocyte folic acid levels were determined in 45 epileptic patients (30 women, 15 men; mean age 31.7 years) and 23 healthy volunteers (control group; 18 women, five men; mean age 33.4 years). All patients were either on carbamazepine (CMZ), oxcarbazepine (OXZ), or valporate (VP) monotherapy. Serum vitamin B12 levels were low in 17.8% of patients and 8.7% of the controls (P = 0.299). Serum homocysteine levels were high in 17.8% of the patients (P = 0.008). Fifty percent of the patients who had hyperhomocysteinemia, and 75% of the patients who had low serum vitamin B12 level were on CMZ monotherapy. Peripheral blood smears showed hypersegmented neutrophils and macrocytosis in 13.3%, hypochromia and microcytosis in 26.7%, acanthocytes in 2.2%, and thrombocytosis in 2.2% of all patients. The control group had normal peripheral blood smears, except in four cases that showed hypocromia and microcytosis. Long-term administration of AED may cause elevation of homocysteine and development of subnormal serum vitamin B12 levels. Peripheral blood smear abnormalities were frequently seen in patients receiving antiepileptic treatment (P = 0.022), particularly in patients on CMZ monotherapy (P = 0.281). However, homocysteine, vitamin B12, folic acid levels and peripheral blood smear findings did not correlate with the drugs used (P = 0.665, 0.336, 0.249 for CMZ, OXZ, VP, respectively).

THE ANEMIA OF INFLAMMATION: A Common Cause of Childhood Anemia

Pediatricians should understand that the anemia of inflammation is second only to iron deficiency in overall incidence. When evaluating a child for mild to moderate anemia, one should always consider hemolytic anemia, both immune and congenital, and blood loss. Careful scrutiny of the peripheral blood smear is always helpful and can assist in minimizing expensive and unnecessary evaluations. When the anemia of inflammation is suggested by history or physical examination and the CBC reveals a normocytic, or possibly microcytic, mild to moderate anemia with a normal peripheral blood smear, it is prudent to not embark on an extensive evaluation for the anemia but instead wait for the inflammation to resolve. This may take as many as 3 months, depending on the degree of inflammation. Because the anemia resolves with subsiding inflammation, it is best to avoid treatment with iron or RBC transfusions. More studies need to be performed concerning the pathogenesis of the anemia of acute inflammation in children and the best course of treatment, if needed. The role of erythropoietin in the treatment of this form of anemia, though promising in some adult models of inflammation, awaits exploration in pediatric patients.

Haemorrhagic disease of the newborn: a review of 127 cases.

A review of 127 infants with haemorrhagic disease of the newborn (HDN) is presented. The case definition of HDN used in the selection of patients was bleeding during the 1st week of life in a newborn with normal platelet count, normal peripheral blood smear and complete clinical response to parenteral vitamin K. Equivocal cases with respect to cause of bleeding were excluded. The eligible cases consisted of 0.9% of all admissions to the unit and the male:female ratio was 1.8:1. Most were from families of low economic status and poor educational background. Omission of vitamin K prophylaxis and exclusive breastfeeding were the commonest antecedents. The mean (SE) gestation and admission weight were 39.3 (0.2) weeks and 2981 (78) g, respectively. One hundred and two (80.3%) had classical HDN with a mean (SE) age at onset of 63 (4.4) hours. Gastro-intestinal bleeding was the commonest observation. Thirty-three infants (26%) died, most of them from exsanguination. There is a need for well designed work to determine the magnitude of the problem, including that of late-onset HDN, the antecedent risk factors, the preferred route for administering prophylactic vitamin K and a clear policy guideline on prevention of the disease.

The demonstration of terminal deoxynucleotidyl transferase on frozen tissue sections and smears by the avidin-biotin complex (ABC) method

A method using avidin-biotin complex (ABC) to detect the presence of the enzyme terminal deoxynucleotidyl transferase (TdT) is described and compared with a proven indirect immunofluorescence method. The material studied consisted of: (1) peripheral blood and bone marrow smears from 17 patients with leukemia (ALL, 8; CLL, 3; AML, 6), six normal controls, one T-ALL cell line, and (2) frozen tissue sections from four patients with lymphoblastic lymphoma (LL), two patients with nodular poorly differentiated lymphocytic lymphoma (NLPD), two patients with reactive follicular hyperplasia (RFH) and one calf thymus. The slides from patients with ALL had from 30 to 90% cells with nuclear positivity by the ABC technique. Slides from patients with CLL were negative, as were the normal peripheral blood smears. Normal bone marrow smears contained less than 5% positive cells. The T-ALL cell line was 100% positive. The frozen tissue sections from the patients with LL and the calf thymus contained numerous positive cells, while all of the sections from the patients with NLPD and RFH were negative. A good correlation existed between the ABC and the indirect immunofluorescence methods. The ABC method described is both more specific and more sensitive than the previously described techniques in detecting TdT in tissue sections and smear preparations.

Diagnosis of Splenomegaly

To the Editor.— In their article Splenomegaly: An Algorithmic Approach to Diagnosis (1981;246:2858), Edward R. Eichner, MD, and C. L. Whitfield, MD, recommend bone marrow aspiration, biopsy, and culture for patients with asymptomatic splenomegaly and normal peripheral blood smears and counts. Following normal bone marrow examination they suggest a splenic computed tomographic (CT) scan, arteriography, and finally consideration of diagnostic splenectomy and laparotomy. However, they note that 3% of healthy college freshmen have been reported to have asymptomatic splenomegaly 1 and, therefore, it is a rather common finding. A ten-year follow-up study of those same students 2 failed to reveal any major disease when compared with a similar control group. Conspicuously absent from the group were the lymphoproliferative diseases. In light of this study it would seem excessively invasive and costly to submit 3% of the freshmen college population to bone marrow aspirations, splenic CT scans, arteriograms, and considerations of

Human granulocyte-specific nuclear antigen(s). II. Detection of antigens in human proliferative syndromes.

Antisera raised to dehistonized chromatin from isolated normal human granulocytes revealed the presence of chromatin-associated antigens specific for the human neutrophils that appear during late stages of myeloid cellular differentiation. Immunological specificity was demonstrated by C fixation, immunodiffusion, and immunocytochemical reactions. Chromatin prepared from both normal granulocytes and specimens of myeloid leukemia showed immunologic reactivity. Although the normal antigens were detected in a specimen of CML, the position of immunodiffusion precipitin lines was different from that obtained with normal granulocyte chromatin. In addition, chromatin prepared from the myeloid leukemic cell line HL-60 expressed only one of the three precipitin bands normally found in immunodiffusion. The immunocytochemical staining reaction was confined to the nucleus of mature neutrophils in normal peripheral blood smears. Greater than 90% of cells in peripheral blood specimens of CML showed positive immunocytochemical nuclear staining. In other types of leukaemia, the normal mature granulocyte reacted with antiserum, but the nonmyeloid leukemic cells in these specimens did not. The specificity of immunologic reactions described here suggests the usefulness of nuclear antigens as cell markers.