What is the diagnosis for a patient with a history of renal cyst and anemia, who underwent a magnetic resonance imaging (MRI) of the abdomen with and without contrast on April 30, 2025, revealing a 4.5 cm simple cyst in the right kidney and potential mild diffuse fatty infiltration of the liver?

From the Guidelines

The MRI of the abdomen with and without contrast shows a simple right renal cyst measuring 4.5 cm in diameter, which is a benign finding that typically requires no treatment, as indicated by the KDIGO 2025 clinical practice guideline for the evaluation, management, and treatment of autosomal dominant polycystic kidney disease (ADPKD) 1. There is also possible mild diffuse fatty infiltration in the liver, which suggests early non-alcoholic fatty liver disease. No other abnormalities were detected in the abdominal organs, including the spleen, pancreas, adrenal glands, gallbladder, and biliary system. The absence of solid masses, abnormal contrast enhancement, free fluid, or ascites is reassuring. For the renal cyst, no follow-up imaging is recommended, as simple hepatic cysts are benign lesions that typically follow an indolent course without significant changes in size over time, according to the EASL clinical practice guidelines on the management of cystic liver diseases 1. The fatty liver finding suggests lifestyle modifications including weight loss if overweight, limiting alcohol consumption, increasing physical activity, and following a balanced diet low in processed foods and sugars. These changes can help prevent progression of fatty liver disease. The anemia mentioned in your history does not appear to be related to any abdominal pathology based on this imaging study, so further evaluation of the anemia through blood tests would be appropriate. Some key points to consider in the management of this patient include:

• The use of MRI with and without IV contrast for characterizing renal lesions, as recommended by the ACR Appropriateness Criteria for indeterminate renal mass 1.
• The importance of lifestyle modifications in preventing progression of fatty liver disease, as suggested by the EASL clinical practice guidelines on the management of cystic liver diseases 1.
• The need for further evaluation of the anemia through blood tests, as the imaging study does not show any abdominal pathology that could be causing the anemia.

From the Research

MRI Findings

• The MRI scan revealed a single simple cyst in the right kidney measuring up to 4.5 cm in diameter, with no signal abnormalities or areas of abnormal enhancement 2.
• There may be some mild diffuse fatty infiltration in the liver, but no focal mass or signal abnormality was detected.
• The pancreas and adrenal glands are normal in size, shape, and position, with no signal abnormalities or masses.
• The gallbladder and biliary system are nondilated with no definite stones, and no free fluid or ascites within the abdomen.

Liver and Kidney Function

• A study published in 2010 found that patients with chronic liver disease have high plasma levels of vitamin B12 and low plasma folate levels 3.
• Another study published in 2022 found that vitamin B-12 malabsorption and renal function are critical considerations in studies of folate and vitamin B-12 interactions in cognitive performance 4.
• The MRI findings of mild diffuse fatty infiltration in the liver may be related to the patient's history of anemia and renal cyst.

MRI Technology and Applications

• A study published in 2015 discussed the principles and techniques of magnetic resonance imaging, including its applications in clinical practice 5.
• Another study published in 2011 discussed the advantages and disadvantages of MRI scans, as well as practical issues for clinicians and patients 6.
• The use of MRI in this case helped to identify the simple cyst in the right kidney and rule out other potential abnormalities in the abdomen.