Case Presentation: A previously healthy, 7-year-old girl presented to the emergency department with intermittent episodes of achy abdominal and right-sided flank pain for one month. The patient’s mother endorsed pain severe enough to wake the patient from sleep, as well as occasional constipation, and an associated 12-lb weight loss over the previous six months. On admission, the patient’s blood pressure was 171/135 mmHg and BMI was 13.47. On exam, a nontender, firm, palpable mass was found in the right upper quadrant with a distinct border along the medial abdomen. Review of symptoms was negative for nausea and vomiting, diarrhea, changes in appetite, dysuria, and hematuria.Initial abdominal ultrasound revealed a 15-cm solid mass likely arising from the right kidney. Further evaluation with a chest, abdomen, and pelvis CT revealed a large, heterogeneous mass in the middle and upper poles of the right kidney, with mass effect on surrounding structures (Image 1). The renal vein was not visualized, indicating tumor thrombus invasion, and several metastatic lesions were visualized in the lungs, liver, and retroperitoneal lymph nodes. Taken together, these findings were concerning for a Wilms tumor.Exploratory laparotomy revealed extensive involvement of the liver. The decision was made to pursue a lymph node biopsy and initiate combination chemotherapy according to the COG DD4A protocol. The patient remained admitted for management of severe hypertension with a combination of lisinopril and amlodipine, with dose adjustments as needed, along with isradipine, labetalol, and hydralazine as first, second, and third line agents when SBP surpassed 130. Eventually, a total right nephrectomy was performed, biopsy results confirmed a diagnosis of Wilms tumor, and post-op pathology revealed favorable tumor histology. Today, the patient’s hypertension is resolved, and she continues with chemotherapy and radiation.
Discussion: Wilms tumor is the most frequently occurring kidney tumor in the pediatric population and accounts for 5-7% of childhood cancers (1). This case demonstrates how pediatric hospitalists can evaluate patients for a Wilms tumor and manage the associated conditions such as hypertensive urgency. Abdominal imaging, such as contrast-enhanced CT or MRI, is most useful in identifying a Wilms tumor (2). Imaging establishes the presence of a tumor while also informing the surgical approach and therapies. Additionally, as seen with our patient, imaging may also reveal tumor thrombus to the renal vein and mass effect which may result in renin-mediated hypertension, requiring inpatient observation and blood pressure stabilization (3). Hypertension due to a Wilms tumor has been shown to be effectively managed by ACE inhibitors (4). In this patient, a combination of lisinopril and amlodipine was largely able to stabilize her blood pressure prior to nephrectomy.
Conclusions: This case is an example of the evaluation and management of a presumably malignant and rapidly growing abdominal mass with associated uncontrolled hypertensive urgency. Clinical significance is found in the diagnostic power of contrast-enhanced CT imaging, in the efficacy of inpatient stabilization of tumor-associated, renin-mediated hypertension using a combination of ACE inhibitors and calcium channel blockers, and in the use of the COG-DD4A protocol to decrease tumor burden in a Wilms tumor with favorable histology.
