We present the case of a 40-year-old man with multiple hypertensive target organ damage due to delayed diagnosis of phaeochromocytoma.
S, a 40-year-old toy maker presented to ED with blood pressure of 211/127 mmHg and pulmonary oedema. He was transferred to ICU for treatment of malignant hypertension. Bed-side ECG and transthoracic echo demonstrated left ventricular hypertrophy and dilated aortic root with aortic regurgitation consistent with hypertensive cardiomyopathy. His medical history includes chronic resistant hypertension, obesity, and idiopathic intracranial hypertension(IIH). Following rapid blood pressure control, he was discharged on prazosin 0.5mg BD, metoprolol 50mg bd, and perindopril 5mg daily.
S attended the ophthalmology clinic with deteriorating vision and was readmitted for management of IIH. He remained hypertensive despite of titration of his anti-hypertensive agents. CT-scan detected a 41mm solid right adrenal mass and MRI-brain revealed central posterior reversible encephalopathy syndrome(PRES). Plasma normetadrenaline was elevated at 20000 pmol/L and urinary noradrenaline was measured at 21800 nmol/24 hr. Following commencement of intensive alpha-blockade, right adrenalectomy was performed. Histology confirmed phaeochromocytoma with GAPP score of 3. His blood pressure rapidly normalised and he was discharged without any anti-hypertensive. Plasma and urinary free metanephrines normalised following surgery and his vision subsequently improved.
The prevalence of phaeochromocytoma in individuals with adrenal mass and hypertension is as high as 14%8. Positive imaging paired with elevated plasma free metanephrines has a sensitivity and specificity of close to 100%2. This raised the question whether early biochemical assessment should be considered despite of acute illness. Diagnostic pitfalls in this case include ascertainment bias of obesity being the sole explanation of the patient’s clinical presentations leading to cognitive anchoring on the initial diagnosis; and the interrupted diagnostic momentum due to fragmentation of patient care affecting clinical follow up.