EVALUATION OF RENAL FUNCTION IN CHILDREN WITH SICKLE CELL ANAEMIA IN STEADY STATE SEEN AT FEDERAL MEDICAL CENTRE OWERRI, NIGERIA

Abstract

Renal disorder can complicate sickle cell anaemia (SCA) and it is a known cause of morbidity
and mortality in affected children and adults. It starts early in childhood usually as an
asymptomatic disease before progressing to renal failure. Renal function in children with SCA
has not been fully explored and conflicting results were reported by the few studies done
(especially) in Africa and Nigeria where morbidity and mortality are higher. Hence, the need
for this study.
This cross-sectional descriptive study was carried out between June 2016 and September 2016
at Federal Medical Centre, Owerri. Renal function of SCA subjects was evaluated using
estimated glomerular filtration rate (eGFR) which was compared with healthy controls with
haemoglobin AA (HbAA). The prevalence of significant proteinuria and haematuria; its
association with eGFR and the effect of past sickle cell crisis ( in the preceding 24 months )
on renal function was also evaluated.
Sixty steady state SCA children and sixty age and sex- matched controls with HbAA aged 2 –
18 years were recruited consecutively from the Paediatric sickle cell clinic and Children out
patient clinic respectively. Mean age of the SCA subjects was 9.0 ± 4.2 years while those of
the control was 9.1 ± 4.2 years with 31 males and 29 females in each group. The male to female
ratio was 1.07:1. Serum creatinine was analysed and GFR estimated using original Schwartz
formula while urinalysis was done using combi 10 SG on first morning urine sample.
The study showed that the mean eGFR was significantly higher in SCA group when compared
to the control (p-value 0.001) and decreased with age. The prevalence of significant proteinuria
and haematuria were more in the SCA group (3.4% and 6.7% respectively) compared to the
control (0% and 0% respectively) though the difference was not statistically significant (p
value 0.496 and 0.119 respectively). No significant association was observed between eGFR
and proteinuria (p-value 1.000) and eGFR and haematuria (p-value 1.000). There was a positive
correlation between eGFR and frequency of past painful crisis that required hospitalization but
it was not statistically significant (r = 0.138, p-value 0.295). Also, there was a positive
correlation between eGFR and number of blood transfusion and it was statistically significant
(r = 0.679, p-value 0.000).
The study has shown that SCA impair renal function. There is low prevalence of significant
proteinuria and haematuria in the SCA subjects but higher than the control. There is no
association between eGFR and proteinuria as well as eGFR and haematuria. Frequent sickle
cell crisis is a risk factor for impaired renal function. It is therefore recommended that baseline
renal function in children with SCA be obtained and monitored regularly and a comprehensive
health care plan be adopted for children with SCA to reduce crisis. This will help reduce
morbidity and mortality associated with sickle cell nephropathy.

EVALUATION OF RENAL FUNCTION IN CHILDREN WITH SICKLE CELL ANAEMIA IN STEADY STATE SEEN AT FEDERAL MEDICAL CENTRE OWERRI, NIGERIA