Purpose or Case Report: History:
A 14-year-old female was brought to the emergency department following a self-harm incident. During her assessment, she was found to have elevated blood pressures and a prolonged QTc interval. She reported frequent episodes of palpitations and dizziness over the past year, often occurring immediately after urination.

Findings:
Initial ultrasound showed unremarkable kidneys and normal hemodynamics in the renal vessels. However, a heterogeneously echogenic mass with increased vascularity on color Doppler was visualized in the left bladder wall. MRI confirmed that the mass originated from the bladder base and extended through the left bladder wall, showing avid contrast enhancement and restricted diffusion. Gallium-68 Dotatate PET/CT demonstrated intense radiotracer uptake in the bladder mass, left pelvic sidewall, and left internal iliac lymph nodes.

The patient underwent chemotherapy and partial cystectomy. Pathology revealed neuroendocrine and nested features with infiltration into the smooth muscle bundles consistent with the muscularis propria of the bladder. Tumor cells tested positive for chromogranin and synaptophysin immunostains, while pan-cytokeratin (AE1/AE3) was negative. Genetic testing identified the R242H variant in the SDHB gene.

Discussion:
Bladder paragangliomas are rare neuroendocrine tumors arising from the sympathetic paraganglia present in the bladder wall. They represent 6% of extra-adrenal paragangliomas and 0.05% of all bladder tumors. Typical symptoms include hypertension, hematuria, and catecholamine-associated symptoms like headaches and palpitations during micturition. Up to 63% of bladder paraganglioma patients have a germline mutation, most commonly in the SDHB subunit gene, increasing their risk of developing pheochromocytomas and additional paragangliomas. Therefore, lifelong biochemical and imaging screening from skull base to pelvis are recommended.

Conclusion:
Bladder paragangliomas are a rare variant of extra-adrenal pheochromocytomas. MRI plays an important role in the pretreatment diagnosis of bladder paraganglioma. Gallium-68 Dotatate PET/CT is highly specific and can help diagnose metastatic spread. Lifelong follow-up is recommended due to the risk of recurrence and metastasis, and the potential for developing additional paragangliomas or pheochromocytomas.
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