Imaging manifestations of Caroli disease with autosomal recessive polycystic kidney disease: a case report and literature review

Abstract

Background: Both Caroli disease (CD) and autosomal recessive polycystic kidney disease (ARPKD) are autosomal recessive disorders, which are more commonly found in infants and children, for whom surviving to adulthood is rare. Early diagnosis and intervention can improve the survival rate to some extent. This study adopted the case of a 26-year-old pregnant woman to explore the clinical and imaging manifestations and progress of CD concomitant with ARPKD to enable a better understanding of the disease.

Case presentation: A 26-year-old pregnant woman was admitted to our hospital for more than 2 months following the discovery of pancytopenia and increased creatinine. Ultrasonography detected an enlarged left liver lobe, widened hepatic portal vein, splenomegaly, and dilated splenic vein. In addition, both kidneys were obviously enlarged and sonolucent areas of varying sizes were visible, but color Doppler flow imaging revealed no abnormal blood flow signals. The gestational age was approximately 25 weeks, which was consistent with the actual fetal age. Polyhydramnios was detected but no other abnormalities were identified. Magnetic resonance imaging revealed that the liver was plump, and polycystic liver disease was observed near the top of the diaphragm. The T1 and T2 weighted images were the low and high signals, respectively. The bile duct was slightly dilated; the portal vein was widened; and the spleen volume was enlarged. Moreover, the volume of both kidneys had increased to an abnormal shape, with multiple, long, roundish T1 and T2 abnormal signals being observed. Magnetic resonance cholangiopancreatography revealed that intrahepatic cystic lesions were connected with intrahepatic bile ducts. The patient underwent a genetic testing, the result showed she carried two heterozygous mutations in PKHD1. The patient was finally diagnosed with CD with concomitant ARPKD. The baby underwent a genetic test three months after birth, the result showed that the patient carried one heterozygous mutations in PKHD1, which indicated the baby was a PKHD1 carrier.

Conclusions: This case demonstrates that imaging examinations are of great significance for the diagnosis and evaluation of CD with concomitant ARPKD.

Keywords: Autosomal recessive polycystic kidney disease; Caroli disease; Diagnosis; Magnetic resonance imaging; Ultrasound.

Fig. 1

Reduced echo in the right liver lobe, thickened bright spot, tortuously dilated portal vein, and color flow signal displays in color Doppler flow imaging, accompanied by slightly dilated bile ducts

Fig. 2

Enlarged spleen volume, full shape, slightly enhanced intradermal echo, fine bright spot, spleen thickness of 5.7 cm, tortuously dilated splenic vein at the hilum (arrow), and the wider part is approximately 1.51 cm

Fig. 3

Both kidneys were enlarged in size and abnormal in shape. Normal renal parenchyma was almost unobservable. The renal cortex was thin, and numerous anechoic, honeycomb-shaped dark areas of varying sizes could be observed (arrow)

Fig. 4

Hepatomegaly and splenomegaly could be observed in the MRI-T2WI; a high cystic signal was identified on the liver surface; and no dilation was observed in the common bile duct (arrow)

Fig. 5

Both kidneys increased diffusely in the MRI-T2WI; normal structures disappeared with scattered high polycystic T2WI signals of different sizes (arrow)

Fig. 6

MPCP revealed a high polycystic signal (arrow) at the distal intrahepatic bile duct, which was connected to the intrahepatic bile duct, and said duct was slightly dilated