Haematological manifestations in cyanotic heart diseases at Kenyatta National Hospital And Mater Hospital, Nairobi
Background: Cyanotic heart disease results in inadequate tissue oxygenation. This in turn triggers increased erythropoietin release from the kidneys in an effort to increase the red cell mass so as to increase oxygen delivery to the tissues. Polycythemia results and often iron deficiency develops as the iron stores are depleted as a result of the sustained erythropoiesis. Polycythemia and iron deficiency both lead to increased blood viscosity and a tendency to bleeding diathesis. The objective of this study was to examine the haematological profile of children with cyanotic heart disease in Kenyatta National Hospital and Mater Hospital, and to document the prevalence of abnormal coagulation and iron deficiency in these children. Method: A cross-sectional descriptive study was carried out at Kenyatta National Hospital and Mater Hospital from August to December 2007. A total of 112 children meeting the eligibility criteria were recruited into the study. Haemoglobin level, Mean corpuscular volume, Mean corpuscular haemoglobin, Peripheral blood film report, serum ferritin levels, Prothrombin time, Activated partial thromboplastin time, Platelet counts and D-dimer levels were determined and recorded. Results: The prevalence of iron deficiency was found to be 16.9% (95% CI 9.8- 24.1%). Abnormalities in the coagulation tests were as follows: Prolonged APTT- 9 32.1% (95% CI 23.5-40.7%) of the study population, prolonged PT-3.6% (95% CI 1.4-8.8%), low platelets-7.1 % (95% CI 3-11 %), and raised D-dimer - 60% (95% CI 50.9-69.1%). The sensitivity of Low MCV in detecting iron deficiency was 58.8% with specificity of 51.2%. For Low MCH the sensitivity was 52.9% with a specificity of 50.6%. Findings of microcytic hypochromic cells on peripheral blood film gave a sensitivity of 50%% and specificity of73.4%. Conclusion: There is a high prevalence of iron deficiency among patients with congenital heart disease with cyanosis in Kenyatta National Hospital and Mater Hospital. Mild to moderate coagulation abnormalities were also noted. Recommendation: Screening for iron deficiency using biochemical methods is recommended for patients with congenital cyanotic heart disease, and routine screening for coagulopathy is recommended prior invasive procedures.