Ultrasonography is a non-invasive, established, safe, quick and accurate method for measurement of liver and spleen size(5). We conducted this study to establish standards of liver and spleen length by ultrsonography in healthy Indian children, based on age, sex and somatometric parameters, as the available literature is scarce(6,7).

We enrolled 650 asymptomatic children between the age-group 1 month to 12 years, visiting the out-patient department either for routine immunization or accompanying their siblings, between January to December 2005. Any child under evaluation for/ follow-up case of a condition which could affect the size of the spleen or liver e.g. viral hepatitis, malaria, hemolytic anemia, enteric fever, congestive heart failure and malnutrition (Grade III and IV, IAP classification) was not included in the study. It was ensured by detailed structured parental history, examination and medical record review (if available) that these children did not have any pre-existing suspected inflammatory, metabolic, traumatic, collagen or hematopoietic diseases and malignancies, that could affect liver and spleen size (excluded, n=11). Informed, written consent was obtained from the accompanying caregivers/parents of all children, and verbal assent taken from all children older than 5 year. No child refused assent, whereas there were 42 parental refusals for participation (in the majority due to lack of time to spare, 85.7%).

Baseline data including the age, sex, height/length and weight were recorded for all the children in a structured performa. The age was recorded to the nearest completed month. An electronic weighing scale (accuracy 50 g) and a wall mounted stadiometer (1 mm markings) were used to measure the weight and height/length, as per standard methodology(8). In each child, the clinicians (SS) identified the acromioclavicular and the sternoclavi-cular joints by palpation and marked the midpoint of a line joining these two points– the midclavicular point. A vertical line was drawn from the midclavicular point to the midinguinal point and was defined as the midclavicular line (MCL). All clinical as well as sonographic measurements were done with reference to this line(9).

Ultrasonographic evaluation: All the children underwent an ultrasonographic assessment of the liver and spleen size on the same day by a single radiologist (RK), who was unaware of the clinical condition and the observations made by the clinician, using a Philips Envisor® Color Doppler system with a multi-frequency 3.5 to 5 MHz probe. The measurement of spleen length was the optically maximal distance at the hilum on the longitudinal coronal view (between the most supero-medial and the most infero-lateral points) as the spleen length at the hilum is considered the most reproducible linear measurement(10). The liver length was measured with the child in supine position and the section level along the MCL was determined by simultaneous demonstration of the right kidney as per standard methodology(11). The upper and lower points of the measurement of the liver span were marked and then measured from the sonographic image. The measurements were made during quiet breathing in younger children and during breath-holding in older children. Neither preparation nor sedation was used.

Statistical analysis: Differences of continuous variables between two independent groups were assessed with the t test and the non-parametric Mann–Whitney test; more than two groups were assessed with analysis of variance. Association between spleen or liver length and each of the three variables- age, height/length and weight was assessed with the Pearson correlation coefficient; to identify the exact pattern of the relationship, non-linear regression analysis was performed. Multiple regression analysis was applied in a backward stepwise fashion to test the independent effect of all the factors on liver/spleen length. All statistical analyses were performed by the biostatistician using STATA 10 software.

TABLE III



Liver and Spleen Size Adjusted for Height/length and Weight on Ultrasound Organometry

Our results provide a standard set of normal range of liver and spleen size according to weight, height, age and sex of the children, as determined by ultrasonography. We also found height to be a significant correlate of the liver and spleen size across all ages and weights, in both the sexes.

The conventional method of recording the hepatic and splenic size by clinical examination has been reported to lack both accuracy and reliability(1,2,7,12-14). There have been quite a few previous reports giving the standard sizes of liver and spleen by ultrasound in children(5,6,9,11,15,16), but none has been done in Indian population. Among the more recent ones, Rosenberg, et al.(9) and Megremis, et al.(5) have provided ultrasonographic data on spleen size in 230 and 512 children, respectively. Of the studies providing normative data on both liver and spleen size, Safak, et al.(16) studied 712, 7-15 year old children and provided data according to bodyweight groups. Konus, et al.(15) studied liver and spleen sizes for 307 children and provided the data in height-range and age-group categories. Our results are comparable to these studies.

As the midclavicular line is known to vary widely when evaluated by different observers, we pre-determined it for the sonographic assessments, thus, consistency of measurement was ensured. A single radiologist performing the ultrasonograhy removed the inter-observer bias. There are also some limitations of our study. The number of subjects in the age group 1-3 months and the number of females in the age-group 3-6 months was less than ten. Further, neonates, and children above 12 year age were not included in the study population due to administrative constraints. Although, many previous studies have published normative data using similar small numbers(5,9), the small sample size in certain groups may affect the generalizability of the values to these age-groups. Nutritional anemia and malnutrition may be associated with organomegaly and were not specifically excluded (except severe malnutrition and clinically obvious anemia). However, by presenting the largest pediatric series so far, we provide a more accurate assessment of liver and spleen sizes in children, especially those in India.

In addition to size, there are several palpatory characteristics of the liver and spleen (tenderness, liver edge, nodularity and consistency of the surface, etc.) that contribute significantly to the overall bedside assessment of the organomegaly. Thus, clinical liver span remains a simple practical measurement of liver size, also providing additional supplemental information, and the most applicable in developing countries. The bedside assessment of liver and splenic enlargement will not obviate diagnostic imaging when such information is vital to further therapeutic management of the patient.

We believe that the results of this study can be used as a practical and comprehensive guide to indicate the normal liver and spleen length range for every child, according to his/ her age and body habitus.

Dr KK Kalra, Medical Superintendent, Chacha Nehru Bal Chikitsalaya, for the permission and logistic support to conduct and publish the study.

Contributors: SS and DM conceptualized the study. BD, SS and DM were involved in patient selection, enrolment and clinical data collection. RK and SA conducted the sonographic evaluation. SS and BD collated the results, conducted the literature search and drafted the manuscript. DM supervised the conduct of the study and the manuscript preparation. RMP was involved in the planning of the study, conducted the statistical analysis, and reviewed the manuscript for important intellectual content. All the authors were involved in the approval of the final manuscript to be published. RK and DM would act as the guarantors for the relevant portions of the manuscript.

Funding: None.

Competing interests: None stated.

1. Zhang B, Lewis SM. A study of the reliability of clinical palpation of the spleen. Clin Lab Haematol 1989; 11: 7-10.

2. Joshi R, Singh A, Jajoo N, Pai M, Kalantri SP. Accuracy and reliability of palpation and percussion for detecting hepatomegaly: a rural hospital based study. Indian J Gastroenterol 2004; 23: 171-174.

4. Mimouni F, Merlob P, Ashkenazi S, Litmanovitz I, Reisner SH. Palpable spleens in newborn term infants. Clin Pediatr (Phila) 1985; 24: 197-198.

5. Megremis SD, Vlachonikolis LG, Tsilimigaki AM. Spleen length in childhood with US: Normal values based on age, sex and somatometric parameters. Radiology 2004; 23:129-134.

6. Chen CM, Wang JJ. Clinical and sonographic assessment of liver size in normal Chinese neonates. Acta Paediatr 1993; 82:345-347.

7. Singh K, Bhasin DK, Reddy DN, Koshy A. Liver span in normal Indians. Indian J Gastroenterol 1985; 4: 73-75.

9. Rosenberg HK, Markowitz RJ, Koelberg H, Park C, Hubbard A, Bellah RD. Normal splenic size in infants and children: sonographic measurements. Am J Roentgenol 1991; 157: 119-121.

10. Deligeorgis D, Yannakos D, Panayoton P. Doxiadis S. The normal borders of the liver in infancy and childhood. Arch Dis Child 1970; 45: 702-704.

11. Dittrich M, Milde S, Dinkel E, Baumann W, Weitsel D. Sonographic biometry of liver and spleen size in childhood. Pediatr Radiol 1983; 13: 206-211.

12. Kirk RM. Clinical assessment of liver enlargement. Indian J Gastroenterol 2004; 23: 163-164.

13. Halpern S, Coel M, Ashburn W, Alazraki N, Littenberg R, Hurwitz S, et al. Correlation of liver and spleen size. Determinations by nuclear medicine studies and physical examination. Arch Intern Med 1974; 134: 123-124.

14. Barkun AN, Camus M, Green L, Meagher T, Coupal L, De Stempel J, et al. The bedside assessment of splenic enlargement. Am J Med 1991; 91: 512-518.