Which condition may present as flank pain and fever in a young woman?

Flank pain and fever in a young woman are classic signs of pyelonephritis, which is a type of kidney infection. This condition typically occurs when bacteria ascend from the bladder (often resulting from a urinary tract infection) to the kidneys. The inflammation caused by the infection can lead to severe flank pain, which is located on the side of the body between the ribs and the hip. Accompanying this pain, fever is a common systemic response to infection, indicating the body is fighting off the invading pathogens.

Pyelonephritis often presents with other symptoms like chills, nausea, and urinary symptoms (such as dysuria or increased frequency), but the specific combination of flank pain and fever is particularly indicative of this renal condition. Recognizing these symptoms is crucial for prompt diagnosis and treatment, as untreated pyelonephritis can lead to more severe complications.

In contrast, conditions like cystitis typically present with more localized bladder symptoms (e.g., painful urination, urgency) rather than flank pain and fever. Pyelectasis refers to dilation of the renal pelvis, which may not necessarily present with these symptoms unless it is associated with infection or obstruction. Adnexitis involves inflammation of the female reproductive organs and might also present