What is the diagnosis in a patient with sickle cell disease who presents with gross hematuria that resolves spontaneously?

In a patient with sickle cell disease presenting with gross hematuria that resolves spontaneously, the diagnosis is consistent with renal papillary necrosis. This condition is a complication associated with sickle cell disease, primarily due to the sickling of red blood cells in the renal microvasculature, which can lead to ischemia and subsequent necrosis of the renal papillae.

The characteristic presentation of renal papillary necrosis includes episodes of hematuria that may occur intermittently, often without any prior noticeable symptoms. The gross hematuria is generally transient and may resolve without intervention, aligning with the scenario described in the question. Additionally, the anatomical site of the papillae being particularly susceptible to ischemic injury makes this diagnosis pertinent in the context of sickle cell disease.

Acute tubular necrosis and acute glomerulonephritis typically present with other features such as changes in urine output, electrolyte imbalances, and potential systemic symptoms that are not mentioned here. Similarly, kidney stones would usually present with acute flanks pain and other associated urinary symptoms. Hence, while these conditions can cause hematuria, renal papillary necrosis is the direct consequence of vascular complications associated specifically with sickle cell disease leading to the described clinical