Differential Diagnosis for Left Flank/Posterior Rib Pain
- Single most likely diagnosis
- Constipation: The patient's poor diet, limited water intake, and sporadic use of Benefiber contribute to the likelihood of constipation. The patient's report of a small bowel movement and left flank/posterior rib tenderness worse with movement also support this diagnosis.
- Other Likely diagnoses
- Musculoskeletal strain: The patient's pain worsening with movement and tenderness in the left flank/posterior rib area could be indicative of a musculoskeletal strain, possibly due to overexertion or poor posture.
- Gastroesophageal reflux disease (GERD): The patient's diet of primarily starch and burgers may contribute to GERD, which can cause referred pain to the left flank or posterior rib area.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Kidney stone: Although the patient denies dysuria, frequency, urgency, and hematuria, and the urine dip is negative, a kidney stone should not be ruled out without further evaluation, as it can be a life-threatening condition if left untreated.
- Pulmonary embolism: Although less likely, pulmonary embolism can cause sudden onset of flank or posterior rib pain and should be considered, especially if the patient has a history of deep vein thrombosis or other risk factors.
- Sickle cell crisis: If the patient has sickle cell disease, a crisis can cause severe pain, including flank or posterior rib pain, and should be considered in the differential diagnosis.
- Rare diagnoses
- Pancreatitis: The patient's diet and limited water intake may contribute to pancreatitis, although it is less likely without other symptoms such as abdominal pain or nausea.
- Shingles: The patient's pain and tenderness in the left flank/posterior rib area could be indicative of shingles, although it is less likely without a rash or other symptoms.
- Spinal infection or tumor: Although rare, spinal infection or tumor should be considered in the differential diagnosis, especially if the patient has a history of cancer or immunocompromised state.