Renal function in adult beta-thalassemia/Hb E disease

Area of Science:

• Nephrology
• Hematology
• Biochemistry

Background:

• Beta-thalassemia hemoglobin E (beta-thal/Hb E) is prevalent in Thailand, characterized by shortened red cell lifespan and iron overload.
• Iron deposition in renal parenchyma is known, but its impact on kidney function in beta-thal/Hb E remains understudied.
• Oxidative stress is implicated in various thalassemia complications.

Purpose of the Study:

• To investigate functional abnormalities of the kidney in patients with beta-thal/Hb E.
• To explore the role of increased oxidative stress in causing renal damage in these patients.

Main Methods:

• Analysis of urine and serum samples from 95 beta-thal/Hb E patients and 27 healthy controls.
• Assessment of creatinine clearance, urinary protein excretion, aminoaciduria, urine osmolality, and specific tubular markers (NAG, beta2-microglobulin).
• Measurement of malonyldialdehyde (MDA) as an indicator of oxidative stress.
• Renal acidification studies and DDAVP challenge in a subset of patients.

Main Results:

• No significant difference in creatinine clearance between patients and controls.
• Beta-thal/Hb E patients showed significantly higher urinary protein excretion, aminoaciduria, and lower urine osmolality.
• Elevated levels of urinary NAG, beta2-microglobulin, and plasma/urine MDA were observed in patients, indicating tubular dysfunction and oxidative stress.

Conclusions:

• This study identifies renal tubular defects in patients with beta-thal/Hb E for the first time.
• Increased oxidative stress, potentially linked to iron deposition, may contribute to these renal abnormalities.
• Further research is needed to understand long-term effects and develop preventive strategies.