Hirudin versus citrate as an anticoagulant for ROTEM platelet whole blood impedance aggregometry in thrombocytopenic patients.

Citrate is widely used as an anticoagulant for platelet function tests (PFTs). Due to an intrinsic inhibitory effect of citrate on platelet function, hirudin is used as an alternative. However, studies comparing the effect of these anticoagulants on rotational thromboelastometry (ROTEM) platelet whole blood impedance aggregometry in thrombocytopenic patients are scant. Cross-sectional study was done in 105 patients who entered the critical phase of Dengue hemorrhagic fever with plasma leakage and severe thrombocytopenia (<100 × 109/L). Samples were collected on two consecutive days and considered as a combined data set for analysis, out of which 200 have been included in the data analysis. Platelet count was used from routine full blood count. ROTEM platelet used TRAPTEM assay, which was performed with 3.2% sodium citrate and 525 ATU/ml hirudin anticoagulated blood. Means of all the TRAPTEM parameters were significantly higher in hirudin, compared to citrate samples (p < .05). Significantly higher overall platelet aggregation was observed in hirudinized samples with a significant mean difference (p < .05) compared to citrate in each quartile of platelet count. Higher platelet aggregation was observed with hirudin compared to citrate in ROTEM platelet whole blood impedance aggregometry in thrombocytopenic patients elaborating the importance of using hirudin anticoagulation in PFTs, particularly in patients with severe thrombocytopenia.

Citrate is the most commonly used anticoagulant for coagulation studies including rotational thromboelastometry (ROTEM).Hirudin is an alternative option to be used as an anticoagulant for PFTs because of the inhibitory effect of citrate on platelet function.One study (Nissen et al. (2020)) reported higher precision and platelet aggregation with hirudinized blood of healthy individuals, over citrate using ROTEM platelet.However, none of the studies were performed in patients in actual clinical context.We evaluated the potential benefit of using hirudin anticoagulated blood over citrate in thrombocytopenic patients due to Dengue hemorrhagic fever using ROTEM platelet.We observed higher platelet aggregation with hirudin compared to citrate suggesting the importance of using hirudin anticoagulation in PFTs, particularly in patients with severe thrombocytopenia.

Rotational thromboelastometry in critical phase of dengue infection: Association with bleeding.

Background: The critical phase of dengue carries a high risk of bleeding. Associations of coagulation test parameters and the risk of bleeding in the critical phase is unclear. This study examines the association of rotational thromboelastometry (ROTEM delta and ROTEM platelet) with bleeding risk of patients with dengue in the critical phase. Methods: A total of 105 patients with confirmed dengue in the critical phase were recruited, with two subsequent prospective time point analyses of ROTEM parameters and platelet count within 24 and 48 hours from the onset of the critical phase. Conventional coagulation tests were performed only at the initial time point. Results: Twenty of 105 patients developed bleeding after onset of the critical phase. Within the first 24 hours of critical-phase onset, platelet count, coagulation tests, and ROTEM delta were unable to differentiate patients with bleeding manifestations from those without (P < .05). Area under the curve of thrombin receptor activating peptide-6 assay of ROTEM platelet (TRAPTEM) discriminated patients with bleeding manifestations from those without, at a cutoff value of <12.5 Ω*min at a sensitivity and specificity of 73.7%, and 60.2%. In patients who developed bleeding, the maximum lysis of extrinsic pathway of ROTEM was significantly lower in patients with severe bleeding compared to those with mild to moderate bleeding. (4.3 ± 3.4% vs 9.4 ± 7.5%; P = .01). Conclusion: An association with bleeding manifestations and TRAPTEM suggest a potential role for defective platelet aggregation in the pathogenesis of bleeding in the critical phase of dengue.

A report of haploidentical allogeneic haematopoietic stem cell transplantation for inherited bone marrow failure in Sri Lanka.

Abstract: Bone marrow failure (BMF) in children can be idiopathic (70-80%) or inherited. Haematopoietic stem cell transplantation (HSCT) is the only cure for both causes. Allogeneic HSCT requires a suitable donor. Many children will not have a HLA matched sibling or unrelated donor. A haploidentical donor is available for all children as eaazch parent will have at minimum a 50% HLA match. This report of a 7-year old girl with BMF treated with a haplo-HSCT, the first in Sri Lanka, highlights the importance of developing a haploidentical HSCT programme as a potential cure for a disease with a dismal outcome.

Transient elevation of serum ferritin in a Sri Lankan with homozygosity for H63D mutation in the HFE gene: a case report.

INTRODUCTION: Hereditary hemochromatosis is an inherited disorder of iron metabolism, characterized by excessive iron deposition in major organs of the body, leading to multi-organ dysfunction. It is a genetically heterogeneous disease caused by mutations in one or more different genes, the most common being mutations in the HFE gene. HFE hereditary hemochromatosis is mostly found in Europeans and is almost always a result of two mutations: C282Y and H63D. The H63D mutation is not as penetrant as the C282Y mutation, but there are rare reported cases of hereditary hemochromatosis with homozygous H63D genotype. While the C282Y mutation is primarily confined to persons of Northern European origin, the H63D mutation is spread worldwide. Other types of hereditary hemochromatosis are rare and broadly defined as non-HFE hereditary hemochromatosis and include mutations in the hemojuvelin gene, hepcidin (HAMP gene), transferrin receptor 2 gene, and ferroportin gene. Hereditary hemochromatosis is commonly found in populations of European origin; in contrast, it is rare and less well understood in Asia. It can be masked by the presence of concurrent iron deficiency or secondary iron overload in thalassemias. CASE PRESENTATION: We report the case of a 42-year-old Sri Lankan man investigated for fatigue during a brief upper respiratory tract infection and found to have high liver transaminases and high serum ferritin, which persisted even after complete resolution of the infection. Homozygosity for H63D mutation in the HFE gene was detected. Liver enzymes, serum ferritin, and transferrin saturation normalized following venesections. CONCLUSION: This case adds to the literature on the importance of being vigilant and investigating patients suspected for iron overload, including genetic studies for hereditary hemochromatosis, even though it is a rare clinical entity in Asians.

Can findings on peripheral blood smear differentiate leptospirosis from other infections? A preliminary comparative study.

Background: Blood smear changes have never been investigated as a potential tool to aid in the diagnosis of leptospirosis. Methods: Blood smears prepared from patients with leptospirosis, dengue and sepsis within the first 5 days of illness were reported by haematologists blinded to the diagnosis. Results: A total of 20, 28 and 22 patients with leptospirosis, dengue and sepsis, respectively, were analysed. Neutrophil leucocytosis, toxic changes in neutrophils, left shift, reactive lymphocytes, target cells and thrombocytopaenia were seen in 60%, 70%, 40%, 70%, 50% and 65% of the leptospirosis patients, respectively. The combination of reactive lymphocytes with toxic neutrophils or neutrophil leucocytosis was highly suggestive of leptospirosis. Conclusions: Peripheral blood smear findings may be helpful in differentiating leptospirosis from other common acute febrile illnesses.