Audiological Correlates of Renal Tubular Acidosis - A Case Report

Abstract

Renal Tubular Acidosis (RTA) refers to a condition where the kidneys do not appropriately eliminate acids from the blood into the urine resulting in acid remnants in the blood. It could be caused either by dysfunction of distal renal tubules or proximal renal tubules. Homeostasis of the cells, cochlear fluids and generation of endocochlear potential are important factors which enable normal cochlear function. Hearing loss can be caused by disturbances in cochlear homeostasis due to certain gene mutations. In this report, a child with proximal Renal Tubular Acidosis who was evaluated and diagnosed as having bilateral sensorineural hearing loss is documented. This report aims to highlight the importance of early diagnosis of hearing loss and provide appropriate intervention to reduce the impact of hearing loss on the child's language, speech, education and social life.

A case report on ATP6V0A4 gene mutation: Forecast of familial deafness by genetic investigation in a patient with autosomal recessive distal renal tubular acidosis

“…The description and confirmation of RTA as a disorder were reported in 1935 and 1946, respectively, followed by the assigning of this term to the disease in 1951 [1][2][3][4][5][6][7][8]. It has been established that RTA should be an acquired or inherited disorder.…”

“…The acquired RTA is induced by certain drugs, such as anticonvulsants, e.g valproic acid, anti-retroviral drugs, and anticancer drugs. Hence, close monitoring through periodic assessments of renal function and hearing of patients taking these drugs is compulsory [1]. Moreover, the inherited variety of RTA occurs through an autosomal recessive or autosomal dominant gene.…”

“…Renal Tubular Acidosis (RTA) is a pathological state that is characterized by chronic acidosis owing to the excessive loss of bases from blood due to impaired reabsorption of bicarbonates or built up of acids in blood due to impaired excretion of hydrogen ions [1]. It leads to malfunctioning of various cells due to systemic electrolyte imbalance, in particular imbalance of chlorine, potassium, and calcium.…”

“…Autosomal Recessive dRTA is due to following defects: (i) H + ATPase B1 subunit defect (The gene responsible for this defect is ATP6B1 on Ch 2p13. These defects are accompanied with bilateral SNHL) [1]; (ii) H + ATPase A4 subunit defect (The gene responsible for this defect is ATP6V0A4 on Ch7q33-34. These defects are accompanied with late onset of SNHL) [1]; and (iii) AE1 defect (The gene responsible for this defect is SLC4A1 on Ch 17.…”

“…These defects are accompanied with bilateral SNHL) [1]; (ii) H + ATPase A4 subunit defect (The gene responsible for this defect is ATP6V0A4 on Ch7q33-34. These defects are accompanied with late onset of SNHL) [1]; and (iii) AE1 defect (The gene responsible for this defect is SLC4A1 on Ch 17. This defect is more prevalent in childhood and in Southeast Asians).…”