The Use of Mean Corpuscular Volume (MCV) to Classify the Anemia As
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The Frequency of Iron Deficiency Anemia and Thalassemia Trait among Children: Experience at Prince Rashed Bin Al- Hassan Military Hospital Zuhair Nusair MD*, Abdelrazzaq Al-Wraikat MD**, Nazih Abu Al-Shiekh MD**, Sameer Kofahi MD^, Mohammad Zoubi MD^ ABSTRACT Objectives: To determine the frequency of iron deficiency anemia and thalassemia trait among children attending the Pediatric Department at Prince Rashed Bin Al-Hassan Military Hospital in the North of Jordan. Methods: This hospital based study was conducted in the year 2008 on 1,012 children aged 6 months to 14 years who attended the Pediatric Department at Prince Rashed Bin Al-Hassan Military Hospital in North of Jordan using fully automated blood count of the mean corpuscular volume, serum ferritin level and high performance liquid chromography, or genotyping. None of the subjects included in the study had been on any hematinic in the previous six months, had infection in the past one month or had a chronic disease. The diagnosis of iron deficiency anemia was defined as mean corpuscular volume ≤ mean – 1 standard deviation corrected for age, with a ferritin level < 7 ng/ml of the serum (normal reference range 7 – 140 ng/ml). The diagnosis of thalassemia trait, for subjects with normal or high serum ferritin and those whose mean corpuscular volume was non-compliant to iron therapy, was obtained by high performance liquid chromography or polymerase chain reaction, which was performed at Princess Eman Research and Laboratory Science Center. Results: The frequency of iron deficiency anemia and thalassemia trait was 13.3% and 5.8% respectively. They were equally frequent among males and females. The age specific-rate was as follows: 6 months to 2 years 7.4% iron deficiency anemia and 1.3% thalassemia trait, 2 - 6 years 3.1% iron deficiency anemia and 2.5% thalassemia trait, 6 - 12 years 1.6% iron deficiency anemia and 1.2% thalassemia trait and 12-14 years 1.3% iron deficiency anemia and 0.9% thalassemia trait. Conclusion: The frequency of iron deficiency anemia (13.3%) and thalassemia trait (5.8%) among children in North of Jordan was estimated by statistical measurement of mean corpuscular volume fL. It is a strong cost efficient predictor in the majority of cases. The red-blood indices complemented with serum ferritin and high performance liquid or polymerase chain reaction are of value for precise diagnosis. Key words: Children, Frequency, Iron deficiency anemia, North of Jordan, Thalassemia Trait JRMS December 2012; 19(4): 70-75 From the Departments of: * Pediatrics, Prince Rashid Bin Al-Hassan Hospital, (PRHH), Irbid-Jordan ** Princess Iman Research and Laboratory Sciences Center, King Hussein Medical Center (KHMC), Amman-Jordan ^ Preventive Medicine, (KHMC) Correspondence should be addressed to Dr. Z. Nusair, (PRHH), Irbid-Jordan, E-mail: [email protected] Manuscript received April 9, 2010. Accepted June 18, 2009 70 JOURNAL OF THE ROYAL MEDICAL SERVICES Vol. 19 No. 4 December 2012 Introduction chain reaction (PCR) is used for the diagnosis of Anemia is a major pediatric health problem and a few number of α-thalassemia trait subjects that iron deficiency anemia (IDA) is the most should be considered in all children of high risk common cause of anemia,(1-3) it is usually due to family origins with a blood picture suggestive of ß-thalassemia trait but in whom the level of HbA2 nutritional imbalances in children among (4) vulnerable groups of population in Jordan, and it and HbF are within normal limits. is an important public health problem The aim of this study was to determine the worldwide.(4-8) frequency of IDA and TT among children Iron deficiency is not normally present in attending the Pediatric Department at Prince hereditary anemias like thalassemias,(9) but it is Rashed Bin Al-Hassan Military Hospital in the one of the causes of microcytic hypochromic North of Jordan based on MCV, serum ferritin anemia. Moreover, in many parts of the world, level and HPLC or PCR. thalassemia trait (TT) as a cause of microcytic anemia is only less prevalent than IDA and is Methods sometimes confused with it, since it is This study was conducted in the period between characterized by microcytosis and sometimes January and December 2008, on all children who mild anemia. The use of mean corpuscular were seen at the out patient clinic of the Pediatric volume (MCV) to classify anemias as microcytic, Department of Prince Rashed Bin Al-Hassan normocytic or macrocytic is a standard Military Hospital in the North of Jordan. The diagnostic approach.(4,9) On other hand the red- study subjects included those whom aged is cell distribution width coefficient variation between 6 months to 14 years old, not on any percentage (RDW-CV%) has been reported to be hematinic in the previous six months, had no of value in the discrimination of IDA from TT.(10- infection in the past one month and had no 12) It is an index of the variation in the size of red chronic diseases. The Jordanian Royal Medical cells and can be used to detect subtle degrees of Services Ethics Committee approved the study. anisocytosis.(13) Therefore, an elevated RDW- All subjects had a complete blood count and CV% appears to be the earliest hematolological RBC indices performed at the first visit during manifestation of IDA.(14-16) the study period. The serum ferritin concentration is particularly The cutoff value for the diagnosis of microcytic informative in estimating the amount of iron anemia was arbitrarily set at MCV ≤ mean – 1 storage and provides direct information about standard deviation (1SD) of the corresponding any deficit in the iron nutritional status. age group. If a subject was found to have an Moreover, it is the first in line to drop if the MCV below the cutoff value, serum ferritin level individual suffers any iron deficiency from was estimated and if it was found < 7 ng/ml diet as seen in IDA.(17-19) On other hand, the (normal reference range 7 - 140 ng/ml) a serum ferritin level, which is usually conducted provisional diagnosis of IDA was made and iron in conjunction with MCV, can indirectly help in replacement therapy was started. RBC indices understanding iron metabolism as MCV were repeated monthly and after 3 months of iron measures how big the red blood cells are. When a replacement therapy if the MCV improved and deficiency in iron occurs, not enough hemoglobin became above the cutoff value, the diagnosis of is made. This leads to a reduced rate of red blood IDA was considered confirmed. If the MCV did cell production and the red blood cells become not improve and remained below the cutoff smaller (microcytic) and paler (hypochromic) value, HPLC was done to confirm or exclude β- than normal.(3,20,21) thalassemia. If β-thalassemia was excluded, PCR The measurement of hemoglobin A2 (HbA2) and was performed to confirm or exclude α- hemoglobin F (HbF) by High performance liquid thalassemia. chromography (HPLC) is rapid, reproducible and If serum ferritin level was within the normal an appropriate method for screening ß- range, a diagnosis of "possible thalassemias" was thalassemia carriers,(22) which have been made and HPLC was done to confirm or exclude characterized by microcytosis, hypochromia and (23) HbA2 above 3.5%. In addition, the polymerase JOURNAL OF THE ROYAL MEDICAL SERVICES 71 Vol. 19 No. 4 December 2012 Table I. Comparison of the RBC indices (n = 1012) and serum ferritin (n = 227) between males and females Parameter Males Females P-Value Hematocrit or PCV (%) 34.6 ± 3.9 34.3 ± 3.8 0.540 MCV fL 74.5 ± 6.5 75.4 ± 6.8 0.051 MCH pg 23.9 ± 2.7 24.2 ± 2.9 0.057 RDW-CV% 14.5 ± 2.3 14.2 ± 2.4 0.077 RBC x 1012/L 4.68 ± 0.59 4.63 ± 0.51 0.140 Serum ferritin 12.9 ± 14.5 13.1 ± 15.2 0.891 Table II. Age-Specific RBC indices Age group No. PCV MCV MCH RDW-CV RBC 6 mo to< 2 yr 403 33.4 ± 3.5 72.8 ± 6.2 22.9 ± 2.6 15.2 ± 2.6 4.69 ± 0.49 2 to< 6 yrs 329 34.3 ± 3.3 75.2 ± 6.2 24.3 ± 2.6 14.1 ± 2.0 4.62 ± 0.64 6 to< 12 yrs 201 35.8 ± 4.2 78.0 ± 5.8 25.5 ± 2.4 13.4 ± 1.6 4.59 ± 0.48 12-14 yrs 79 36.7 ± 4.6 76.8 ± 8.6 24.6 ± 3.6 14.1 ± 2.4 4.79 ± 0.61 Overall 1012 34.4 ± 3.8 74.9 ± 6.6 24.0 ± 2.8 14.4 ± 2.3 4.66 ± 0.56 Table III. Age-specific frequency of IDA and TT Age group Non-anemic IDA TT No. (%) No (%) No (%) 6 mo to< 2 yr 315 (31.1) 75 (7.4) 13 (1.3) 2 to< 6 yrs 273 (27.0) 31 (3.1) 25 (2.5) 6 to <12 yrs 173 (17.1) 16 (1.6) 12 (1.2) 12 to <14 yrs 57 (5.6) 13 (1.3) 9 (0.9) Total 818 (80.8) 135 (13.3) 59 (5.8) Table IV. Gender-specific frequency of IDA and TT Age Non-anemic IDA TT No (%) No (%) No (%) Males 436 (43.1) 83 (8.2) 35 (3.6) Females 382 (37.7) 52 (5.1) 24 (2.4) Total 818 (80.8) 135 (13.3) 59 (5.8) P-value 0.054 0.520 Table V. Comparison of the serum ferritin (n = 227) and RBC indices (n = 1012) between IDA, and TT.