Background: Bladder paraganglioma can present without urinary or hypertensive symptoms. However, the catecholamine excess can cause impaired glucose tolerance and adrenergic cardiomyopathy.
Case: A 67-year-old male presented in fulminant diabetes mellitus (DM). This is on the background of acute dilated cardiomyopathy diagnosed five months prior, without a history of DM. Type 1 DM autoantibodies were negative. Abdominal CT did not reveal a pancreatogenic cause of DM, but incidentally detected a bladder soft tissue mass. Plasma normetanephrine was markedly elevated 6991pmol/L, and 7147pmol/L on repeat (N<1080). 24-hour urinary normetanephrine was 9.5umol/24hours (N<4.5). Ga68-DOTATATE PET showed heterogeneous and intense DOTATATE activity associated with the soft tissue mass. He was diagnosed with bladder paraganglioma and referred for elective robotic assisted partial cystectomy. He was managed with phenoxybenzamine, metoprolol, and salt tablets preoperatively. During this time, his glycaemic control and heart failure both dramatically improved.
Discussion: Approximately 10% of catecholamine-secreting paragangliomas are located in the bladder and prostate.(1) Symptomatic paragangliomas often present with catecholamine hypersecretion or local mass effect. Bladder paragangliomas can present with hypertension, haematuria, and micturition syncope.(2) These episodes are generally triggered by bladder distension or micturition.(3) However, patients can also be asymptomatic at time of diagnosis.(2)
Functional paragangliomas are associated with DM due to catecholamine excess, resulting in impaired glucose metabolism.(4) Resection of the paraganglioma results in improvement of glycaemic profile and reduction of hypoglycaemic agents.(5) Functional paragangliomas are also associated with adrenergic cardiomyopathy.(6) This differential should be considered in cases of non-ischaemic cardiomyopathy, as management and outcomes are quite different.
Conclusions: This case highlights the variable presentation of a secretory bladder paraganglioma, presenting with adrenergic cardiomyopathy and fulminant DM, yet without hypertension or bladder symptoms. A high index of suspicion should be maintained, especially in those presenting with atypical DM or non-ischaemic cardiomyopathy.