Differential Diagnosis for Flank Pain in Pregnancy
Single Most Likely Diagnosis
- Pyelonephritis: This is a common cause of flank pain in pregnancy, especially in the second and third trimesters. The urinary tract changes and compression from the expanding uterus increase the risk of urinary tract infections.
Other Likely Diagnoses
- Nephrolithiasis: Kidney stones can cause severe flank pain and are a common condition in pregnancy. The pain typically radiates to the groin and is often accompanied by nausea, vomiting, and hematuria.
- Musculoskeletal strain: The growing uterus can put strain on the back muscles, leading to flank pain. This is a common complaint in pregnancy, especially in the third trimester.
- Urinary tract infection (lower): While not as severe as pyelonephritis, lower urinary tract infections can still cause flank pain and are common in pregnancy.
Do Not Miss Diagnoses
- Placental abruption: This is a life-threatening condition where the placenta separates from the uterus, causing severe abdominal and flank pain. It requires immediate medical attention.
- Preeclampsia: This condition can cause flank pain, among other symptoms like hypertension and proteinuria. It is a serious condition that can lead to maternal and fetal complications if not promptly treated.
- Appendicitis: Although less common in pregnancy, appendicitis can cause flank pain and requires prompt surgical intervention to prevent complications.
Rare Diagnoses
- Renal vein thrombosis: This is a rare condition that can cause flank pain and is more common in patients with nephrotic syndrome or other hypercoagulable states.
- Ovarian torsion: This is a rare condition that can cause severe flank pain and requires prompt surgical intervention to preserve ovarian function.
- Adrenal hemorrhage: This is a rare condition that can cause flank pain and is often associated with trauma, anticoagulation, or underlying adrenal disease.