A Study to Find out the Role of Zinc Protoporphyrin as a Diagnostic Tool in Anaemia

Abstract

Introduction: Iron deficiency anaemia is one of the most common nutritional deficiencies in India leading to reduced work productibility, impaired mental and motor development in children and adverse outcome of pregnancy. Various and numerous tests are available for detection of Iron deficiency anaemia but some are costly and also range widely in specificity and sensitivity. Co-existence of Iron deficiency anaemia in sickle cell anaemia is often masked by the clinical features of Sickle cell disease and also because the patients are already anaemic. Zinc Protoporphyrin is a normal metabolite of heme synthesis but increases when there is depletion of Iron in the body. This study was done to determine the role of Zinc Protoporphyrin as a screening tool for the diagnosis of Iron deficiency anaemia in patients clinically presenting with features of anaemia and also in sickle cell anaemia patients. Aim & Objective: To determine Zinc Protoporphyrin level and to correlate with other parameters of Iron Deficiency. To find out the role of ZnPP in sickling disorder. Methodology: This study was carried out at Dhiraj hospital and consisted of 51 patients, out of which 5 patients were of sickle cell anaemia. Adult patients who were having anaemia and having clinical as well as laboratory evidence of Iron deficiency were taken for the study. They were subjected to a detailed history and clinical examination and blood investigations like CBC with indices, other haematological and biochemical investigations, sickling solubility, Iron profile and Hb electrophoresis was done. Hemoglobin analysis was done by HPLC, and Zinc Protoporphyrin was done by Haematoflourometry. Discrimination index like Mentzer and Srivastava index was also calculated. Result: Out of 51 patients, 26 were male and 25 were female. 25(49%) out of 51 were above the age of 50 years. Out of the 5 patients of sickle cell anaemia, 3 had SCD and 2 had SCT. All the patients complained of generalized weakness and on examination had pallor. Mean Hb observed was 7.54±2.22, mean MCV was 67.56±8.49, mean MCH of 20.26±4.75, mean MCHC of 28.20±2.84, mean PCV 24.59±6.51, mean RBC XI 3.46±0.882, mean RDW 20.48±4.75, mean S.Iron 37.58±16.82, mean S.Ferritin 194.64±293.98 and mean TIBC was 359.63±65.54.13 patients had mild anaemia (25.4%), 18 patients had moderate anaemia (35.2%) and 20 patients had severe anaemia (39.2%). The lowest value of Zinc Protoporphyrin was 16 which was less and maximum was 577 which was more than the normal range. Out of 51 patients, 2 patients (3.92%) had Zinc Protoporphyrin in normal range, 1 patient had below normal (1.96%), 15 patients (29.4%) had in the range of 40-100, 25 patients (49%) had in the range of 101-200, 6 patients (11.7%) had in the range of 201-400 and 2 patients(3.92%) had values of more than 400. Zinc Protoporphyrin (ZnPP) represented iron deficiency in majority except in three patients in whom it was false negative. Majority of patients had blood indices in a below normal range. Mentzer Index (MI) and Srivastava Index (SI) was increased in 48 (94%) patients. In the remaining 3 patients MI was below normal in 2 and normal in 1 patient. All the three patients had SI below normal range. Conclusion: ZnPP is a good indicator for detecting Iron deficiency particularly in patients who are hospitalized and also in those who are elderly. Though only 5 patients of Sickle cell disorder could be studied, they were iron deficient and ZnPP can be used as one of the tool to detect it.