Renal Functions in Pediatric Patients with β-Thalassemia Major: Relation to Iron Chelation Therapy

Document Type : Original Article

Authors

1 Department of Physiology , Faculty of Medicine, Assiut University.

2 Department of Medical Biochemistry, Faculty of Medicine, Assiut University.

Abstract

Renal failure is one of the main complications in β-thalassaemia as a result of longstanding
anemia, therefore the objectives of the study were: (1) To investigate
glomerular and tubular functions in transfusion dependant (TD) β-thalassaemia
major (βTM) pediatric patients without any occult renal diseases. 2) To correlate the
findings with clinical parameters, oxidative stress status [by measuring serum total
antioxidant capacity (TAC) and urinary malondialdehyde (MDA)] and
desferrioxamine (DFO) chelation therapy. Patients and methods: The study included
sixty-nine TD-βTM patients (45 males and 24 females). They were subdivided into
those with (34 patients) and without chelation therapy (35 patients). In addition to
fifteen age-, sex-, body mass index (BMI)-matched healthy subjects as a control
group. From each participant blood sample was taken for determination of the serum
(S) levels of creatinine (Cr), albumin, calcium (Ca), inorganic phosphorus (PO4), uric
acid (UA), cystatin-C (CysC) and TAC. Also a urine sample was taken for
determination of urinary (U) levels of creatinine, albumin, N-acetyl-beta-Dglucosaminidase
(NAG) activity, β2-microglobulin (β2MG) and MDA. Results: The
results revealed that in βTM patients the serum levels of Cr, albumin, PO4, UA, CysC,
and urinary levels of NAG/Cr, β2MG/Cr, MDA/Cr, albumin/Cr were significantly
higher; while serum TAC, estimated glomerular filtration rate (eGFR) were
significantly lower than those of the controls. In patients with chelation therapy,
serum levels of CysC, and albumin were significantly higher while, TAC was
significantly lower than those without chelation therapy. Significant positive
correlations were observed in TD-βTM patients between SCysC and each of Salbumin
and SCr; STAC and eGFR and UNAG/Cr with each of Uβ2MG/Cr, UMDA/Cr and
Ualbumin/Cr. Also, significant negative correlations were found between SCysC and
eGFR; STAC and each of SCys, SCr, and Salbumin. Conclusion: The results of the
present study confirm that renal tubular dysfunction exists in children with βTM
which could be attributed to iron overload, oxidative stress and DFO therapy.

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