Sonographic Assessment of the Size and Parenchymal Echo Texture of the Spleen among Sickle Cell Disease Patients at University of Nigeria Teaching Hospital, Ituku-Ozalla, Nigeria

Abstract

Regional variations in splenic size and spleen parenchymal echo-texture among sickle cell

disease (SCD) patients have been documented in various publications. The objectives of this

study were to: determine and compare the spleen size of SCD patients with those of the control;

characterize the spleen parenchymal echo-texture of SCD patients; and ascertain the relationships

of age, height and weight with the spleen sizes of SCD patients and the controls.

This was a cross sectional prospective study conducted at the SCD clinics and radiation medicine

department of the University of Nigeria Teaching Hospital (UNTH), Ituku-Ozalla, Enugu,

between September, 2012 and November, 2013. Ethical approval was obtained from the

hospital's Health Ethics Committee, and informed consent was obtained from each subject prior

to the commencement of the study. Convenience sampling technique was used to enlist 103

stable SCD subjects and 103 healthy age matched control subjects that were aged 2 - 58 years.

Aloka ST-550 - 3500 real time ultrasound machine with 3.5 MHz and 5 MHz probes was used to

scan the enlisted subjects. Trans-abdominal longitudinal scan of the spleen was carried out on the

selected subjects. The largest inter-polar distance of the spleen was measured as the length, while

the longest distance between diaphragmatic surface of the spleen and the splenic hilum was

measured as the width. The parenchyma echo texture of each spleen was scrutinized, and

characterized based on the following criteria: normal; fine hyper echoic; coarse hyper echoic;

fibrotic scar littered; infarction/abscess littered; and calcification littered parenchyma.

Relationship between the mean spleen sizes and age, height, and weight of the subjects were

determined using Pearson's correlation coefficient.

The mean spleen sizes of SCD patients (97.67 ± 39.61 mm for spleen length and 47.28 ± 20.68

mm for spleen width) were generally larger than those of the controls (80.84 ± 16.89 mm for

spleen length and 39.38 ± 9.39 mm for spleen width) (p < 0.05). Parenchymal echo-textures of

the spleens in SCD patients revealed normal spleen parenchyma (8.74%); fibrotic scar littered

parenchyma (21.36%); infarction/abscess littered parenchyma (2.91%); calcification littered

parenchyma (4.85%); fine hyper echoic parenchyma (19.42%); and coarse hyper echoic

parenchyma (19.42%), while normal spleen parenchyma was visualized in all the control

subjects. There were negative correlations between mean spleen sizes and age (r = -0.13), height

(r = -0.17), and weight (r = -0.06) among SCD subjects, whereas there were positive correlations

between mean spleen sizes and age (r = 0.63), height (r = 0.85), and weight (r = 0.83) in the

control subjects.

The results of this study suggest that inclusion of routine sonographic evaluation of the spleen in

the management of patients with SCD will be very useful.