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 stasis and infection.
Other Likely Diagnoses
- Nephrolithiasis: Kidney stones can cause severe flank pain and are more common during pregnancy due to increased urine calcium excretion and urinary stasis.
- Musculoskeletal strain: The growing uterus can put strain on the back muscles, leading to flank pain.
- Urinary tract infection (UTI): Asymptomatic bacteriuria is common in pregnancy, and UTIs can cause flank pain.
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.
- Preeclampsia: Severe preeclampsia can cause flank pain, and it is essential to diagnose and manage promptly to prevent complications.
- Appendicitis: Although less common, appendicitis can occur during pregnancy and may present with flank pain, especially if the appendix is located in the retrocecal position.
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: Although rare, ovarian torsion can cause severe flank pain and is a surgical emergency.
- Adrenal hemorrhage: This is a rare condition that can cause flank pain and is often associated with trauma or anticoagulation.