Differential Diagnosis
- Single most likely diagnosis
- Urinary Tract Infection (UTI) with possible contamination: The presence of leukocytes (250 WBC) and calcium oxalate in the urine suggests a possible infection, despite the urine culture being negative. This could be due to a low bacterial load, contamination, or an infection caused by an organism that does not grow well in standard culture media.
- Other Likely diagnoses
- Kidney stones (nephrolithiasis): The presence of calcium oxalate in the urine is a common finding in patients with kidney stones. The leukocytes could be indicative of an associated infection or inflammation.
- Interstitial nephritis: This condition, often caused by an allergic reaction or sensitivity to certain medications, can lead to inflammation in the kidneys, resulting in leukocytes in the urine.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Sepsis: Although the urine culture is negative, the presence of leukocytes could indicate a systemic infection. Sepsis is a life-threatening condition that requires immediate attention.
- Pyelonephritis: An infection of the kidney, which can be severe and lead to sepsis if not properly treated. The presence of leukocytes and the clinical context should raise suspicion for this condition.
- Rare diagnoses
- Tubulointerstitial disease: A group of disorders that affect the tubules and interstitial tissue of the kidneys, which could lead to the presence of leukocytes in the urine.
- Malignancy: Certain types of cancer, such as bladder or kidney cancer, can cause leukocytes in the urine. Although rare, this possibility should be considered, especially in patients with risk factors or other suspicious symptoms.