MRI of the abdomen does not allow for detection of pelvic abnormalities including urolithiasis in the distal ureters or urinary bladder, congenital abnormalities of the distal ureters and abnormal insertion sites, and abnormalities of the urinary bladder, among other potential sources of APN. MRI of the abdomen is generally safe in pregnant patients and may be useful in certain situations [28-30]. Although there are no known adverse effects to human fetuses and no known cases of nephrogenic systemic fibrosis linked to the use of clinical doses of GBCAs in pregnant patients, GBCAs should only be used if the indication is considered critical and the potential benefits justify the potential unknown risk to the fetus [47]. MRI of the abdomen may allow for a limited evaluation of the embryo or fetus, although most fetuses would not be included in the field of view. The main disadvantages of MRI are poor accuracy for the detection of small urothelial calculi and reduced accuracy for detection of emphysematous pyelonephritis [31,32]. MRU There is no current literature specific to the use of MRU without IV contrast in the evaluation of suspected APN in pregnant patients. The excretory phase of MRU does not confer additional benefit with respect to detection and characterization of APN in a pregnant patient. Radiography Abdomen and Pelvis Radiography of the abdomen and pelvis is not beneficial in the imaging evaluation for suspected APN in a pregnant patient [15]. Radiography Intravenous Urography IVU is not beneficial in the imaging evaluation for suspected APN in a pregnant patient [15]. US Abdomen There is no current literature specific to the use of US of the abdomen in the evaluation of suspected APN in pregnant patients. Pregnancy increases the risk of complications from APN, although poor obstetrical outcomes are rare [48]. US of the abdomen may be used to detect complications of APN.
Acute Pyelonephritis. MRI of the abdomen does not allow for detection of pelvic abnormalities including urolithiasis in the distal ureters or urinary bladder, congenital abnormalities of the distal ureters and abnormal insertion sites, and abnormalities of the urinary bladder, among other potential sources of APN. MRI of the abdomen is generally safe in pregnant patients and may be useful in certain situations [28-30]. Although there are no known adverse effects to human fetuses and no known cases of nephrogenic systemic fibrosis linked to the use of clinical doses of GBCAs in pregnant patients, GBCAs should only be used if the indication is considered critical and the potential benefits justify the potential unknown risk to the fetus [47]. MRI of the abdomen may allow for a limited evaluation of the embryo or fetus, although most fetuses would not be included in the field of view. The main disadvantages of MRI are poor accuracy for the detection of small urothelial calculi and reduced accuracy for detection of emphysematous pyelonephritis [31,32]. MRU There is no current literature specific to the use of MRU without IV contrast in the evaluation of suspected APN in pregnant patients. The excretory phase of MRU does not confer additional benefit with respect to detection and characterization of APN in a pregnant patient. Radiography Abdomen and Pelvis Radiography of the abdomen and pelvis is not beneficial in the imaging evaluation for suspected APN in a pregnant patient [15]. Radiography Intravenous Urography IVU is not beneficial in the imaging evaluation for suspected APN in a pregnant patient [15]. US Abdomen There is no current literature specific to the use of US of the abdomen in the evaluation of suspected APN in pregnant patients. Pregnancy increases the risk of complications from APN, although poor obstetrical outcomes are rare [48]. US of the abdomen may be used to detect complications of APN.