<![CDATA[Background: Autosomal Recessive Polycystic Kidney Disease (ARPKD) is a multisystem genetic disorder that primarily affects the kidneys and liver due to a mutation in the PKHD1 gene. Renal manifestations can be observed from the prenatal period through childhood. Ultrasonography (USG) is the primary imaging modality for detecting renal abnormalities in ARPKD, through assessment of kidney size, parenchymal echogenicity, corticomedullary differentiation, and the presence of cysts. Case Presentation: A 9 month old female patient presented with a history of kidney abnormalities that had been detected during the prenatal period. The patient had a history of abdominal distension and recurrent infections, including urinary tract infections. Abdominal ultrasound examinations at 2 and 9 months of age revealed enlargement of both kidneys, increased parenchymal echogenicity, indistinct parenchymal borders and central echo complexes, as well as multiple thin-walled, round anechoic lesions in both kidneys. Discussion: The ultrasound findings for ARPKD vary with age. During the prenatal to neonatal period, findings may include bilateral renal enlargement, increased echogenicity, reduced corticomedullary differentiation, and microcysts. From 4 weeks to 1 year of age, renal enlargement and increased parenchymal echogenicity remain the primary findings, while cysts may become increasingly visible on ultrasound. In this case, ultrasonography revealed bilateral renal enlargement and multiple thin walled, round anechoic lesions in both kidneys. Increased parenchymal echogenicity and indistinct boundaries between the renal parenchyma and central echo complex were also reported on the second examination. These findings support the suspicion of ARPKD, although further clinical evaluation and, when indicated, genetic testing may be required to establish the underlying etiology. Conclusion: ARPKD can reveal kidney abnormalities from the prenatal period through childhood. Ultrasonography plays a crucial role in detecting and evaluating ARPKD by assessing kidney size, parenchymal echogenicity, corticomedullary differentiation, and the presence of cysts. In this case, bilateral ultrasound findings—including renal enlargement, increased echogenicity, reduced corticomedullary differentiation, and multiple anechoic lesions support the suspicion of ARPKD at 9 months of age. Keywords: Autosomal Recessive Polycystic Kidney Disease, ARPKD, ultrasonografi, ginjal polikistik]]>
