Platelet count in impedance-based hematology analyzer: Beware of trap!

Among the blood counts, platelet count is most often reported with inconsistency. Many of the analyzers work on electrical impedance principle for red blood cell (RBC) and platelet counting. However, with this technology, factors such as fragmented RBCs, microcytes, cytoplasmic fragments of leukemic cells, lipid particles, fungal yeast forms, and bacteria are known to interfere with platelet count and give spuriously elevated platelet counts. A 72-year-old male was admitted for the treatment of dengue infection who had serial platelet count monitoring. He had an initial platelet count of 48,000/cumm which suddenly improved to 2.6 lakhs within 6 h without any platelet transfusion. Peripheral smear however did not correlate with the machine-derived count. Repeat test after 6 h yielded a result of 56,000/cumm which correlated well with the peripheral smear. This falsely elevated count was due to the presence of lipid particles as the sample was drawn in the postprandial state.

Prevalence of constitutional macrothrombocytopenia in the immigrants of Northern and Eastern states of India.

BACKGROUND: Thrombocytopenia is generally alarming to both clinicians and patients as the consequence can be disastrous. However, some of the conditions associated with thrombocytopenia can be innocuous. Unless this is recognized, detection of thrombocytopenia results in series of further investigations and management plan by clinicians. Hematological investigation in an apparently healthy/asymptomatic individual can throw up many surprises. One of them is thrombocytopenia and giant platelets on peripheral smear examination. Asymptomatic constitutional macrothrombocytopenia (also called as Harris platelet syndrome) is increasingly recognized in north and eastern parts of India. However, this condition is nearly unknown in southern part of our country. With Increased immigrants to south India from northern and eastern states, it becomes imperative for both clinicians and lab physicians to be aware of the magnitude of the condition and interpret appropriately. This can avoid unnecessary anxiety and investigations. MATERIALS AND METHODS: Blood samples from 300 north and northeastern immigrants (Cases) and equal number of healthy subjects from south India (Controls) were examined for hematological parameters. Peripheral smears were examined for the presence of giant platelets. Results: Constitutional macrothrombocytopenia was seen in 4.3% of the cases and in 0.66% of the controls. The difference was statistically significant with a Fischer exact P value of 0.0067. The prevalence of macrothrombocytopenia on subjective assessment of peripheral smear was 6.7% in the cases and 1% in the control group. CONCLUSIONS: The prevalence of Harris platelet syndrome was found to be 4.3% in the immigrants from north and northeastern states.

Dilemma in Diagnosis of Pyogenic Meningitis in Cerebrospinal Fluid Contaminated with Blood: Does Leucocyte Esterase Test Help?

CONTEXT: Pyogenic meningitis is often a devastating condition which is diagnosed by analysis of cerebrospinal fluid (CSF) obtained by lumbar puncture (LP). CSF thus obtained can get contaminated with peripheral blood leucocytes during LP which renders it unusable for cytological analysis. Leucocyte esterase strips are available for identifying leucocyte esterase activity in urine and other body fluids which suggest inflammation. We conducted this experiment to see whether the leucocyte esterase strip can differentiate between neutrophils invited at the inflammatory site and circulating neutrophils in CSF. AIM: To compare the diagnostic ability of the leucocyte esterase test between pyogenic meningitis and CSF contaminated with circulating neutrophils. SETTING AND DESIGN: Prospective analytical study conducted in a tertiary care hospital. MATERIALS AND METHODS: The CSF samples of pyogenic meningitis patients were analyzed for leucocyte esterase activity. The other group was normal CSF which was deliberately contaminated with buffy coat preparation, and leukocyte esterase activity was determined. STATISTICAL ANALYSIS: Diagnostic ability of a test in terms of sensitivity and specificity. RESULTS: Overall sensitivity of the dipsticks in diagnosing pyogenic meningitis is 81% and specificity is 99%. When compared with experimentally contaminated CSF sample, a reading of 2+ on the strip had a sensitivity of 70% and specificity of 100% for pyogenic meningitis. CONCLUSION: Leucocyte esterase strip is specific for pyogenic meningitis (activated neutrophils), and hence can differentiate from CSF contaminated with blood.

Fine needle aspiration cytology of solitary fibrous tumor of the orbit.

Solitary fibrous tumor (SFT) is a distinct and a rare spindle cell neoplasm, commonly known to occur in the pleura and other serosal sites. With the advent of immunohistochemistry, varied extraserosal sites are being recognized as common locations for this rare tumor. We report a case of SFT in a 50-year-old male patient who presented with multiple swellings in the eyelid, with emphasis on the cytological features.

Comparison of Cell Preparations between Commercially Available Filter Cards of the Cytospin with Custom Made Filter Cards.

INTRODUCTION: Cytological evaluation of body fluids is an important diagnostic technique. Cytocentrifuge has contributed immensely to improve the diagnostic yield of the body fluids. Cytocentrifuge requires a filter card for absorbing the cell free fluid. This is the only consumable which needs to be purchased from the manufacturer at a significant cost. AIM: To compare the cell density in cytocentrifuge preparations made from commercially available filter cards with custom made filter cards. MATERIALS AND METHODS: This was a prospective analytical study undertaken in department of pathology of a tertiary care centre. A 300 GSM handmade paper with the absorbability similar to the conventional card was obtained and fashioned to suit the filter card slot of the cytospin. Thirty seven body fluids were centrifuged using both conventional and custom made filter card. The cell density was measured as number of cells per 10 high power fields. The median cell density was compared using Mann-Whitney U test. The agreement between the values was analysed using Bland Altman analysis. RESULTS: The median cell count per 10 High power field (HPF) with conventional card was 386 and that with custom made card was 408. The difference was not statistically significant (p = 0.66). There was no significant difference in the cell density and alteration in the morphology between the cell preparations using both the cards. CONCLUSION: Custom made filter card can be used for cytospin cell preparations of body fluids without loss of cell density or alteration in the cell morphology and at a very low cost.

Cannonballs in Pap Smears: Double Whammy of Bacterial Vaginosis and Associated Infections.

INTRODUCTION: Cannonballs are structures consisting of neutrophils adherent to epithelial cells, often seen in vaginal Pap smears of patients with trichomoniasis and chlamydiasis. We frequently observed these cannonballs in inflammatory Pap smears showing evidence of bacterial vaginosis. OBJECTIVE: To study the association between cannonballs and bacterial vaginosis with associated infections in inflammatory Pap smears. STUDY DESIGN: This was a retrospective study performed over a period of 6 months between April 2014 and September 2014. Three hundred consecutive Pap smears assessed during the study period were retrieved from the archives and studied. RESULTS: A total of 280 smears were studied. Neutrophilic infiltrates were seen in 83.6%, cannonballs in 82.3%, and bacterial vaginosis in 70.7% of the smears. Cannonballs were found in 84.4% of the smears showing evidence of bacterial vaginosis with associated inflammatory infiltrates. There was a significant association between cannonballs and bacterial vaginosis (p = 0.0001). The odds ratio was 13.8 (95% CI: 7.2-26.2). CONCLUSION: The present study shows a significant association between cannonballs and bacterial vaginosis and associated vaginal infections.

Blood Contamination of the Small Bore Peripheral Intravenous Catheter in Neonates.

INTRODUCTION: Peripheral Intravenous Catheters (PIV) are extensively used in sick neonates for administration of medicines and nutrition. When these PIVs are used on intermittent basis, they are flushed with saline in order to keep the hub of the catheter free from blood. Presence of blood in the hub of the catheter can be potentially dangerous as it could facilitate infection. AIM: The aim of this study was to find the magnitude of blood contamination of PIV catheter hub after routine flushing. MATERIALS AND METHODS: We measured the volume of 24 g PIV by filling it with saline and thereby measuring its volume. The PIVs which were in situ for at least 6 hours and removed were used for this study. These catheters were flushed with 0.2 ml of saline and the RBC count was calculated. RESULTS: A total of 94 PIVs were studied, out of which 84% showed blood tinged residual flush and 15% of them had visible blood clot. All (100%) of the catheter studied showed RBCs on microscopic examination. The median RBC count was 36960/cu mm and the interquartile range was 10000 - 113920/cu mm. The highest RBC count was 2080000/cu mm. CONCLUSION: Blood contamination of the small bore PIVs after flushing is universal in neonates.

Morphologic heterogeneity in carcinosarcoma of the gallbladder: report of a rare cases.

Carcinosarcoma is a rare tumor composed of variable proportions of carcinomatous and sarcomatous elements and comprises less than one percent of all gallbladder malignancies. In most reported cases of carcinosarcoma of gallbladder, the epithelial component is adenocarcinoma. The mesenchymal component varies from homogenous sarcoma to more heterotopic elements like malignant bone, cartilage, and other mesenchymal tissues. We report a rare case of carcinosarcoma of the gallbladder in an 83-year-old male, with the carcinomatous component represented by undifferentiated carcinoma (spindle and giant cell type with osteoclastic giant cells) and the mesenchymal component seen as foci of chondrosarcoma.

Neuromuscular and vascular hamartoma of the small bowel: a rare cause of intestinal obstruction.

Neuromuscular and vascular hamartoma (NMVH) is a rare lesion arising chiefly in the small intestine. As it shares many of the histological features with other commonly occurring stricturous conditions of the small bowel, there is an ongoing debate whether it is truly hamartomatous or represents just a reactive condition. We are reporting a case of NMVH in the terminal ileum in a 32-year-old male who presented with symptoms of intestinal obstruction.