A woman diagnosed with AHT at the age of 14, when she was first admitted to a paediatric hospital, with blood pressure (BP) of 210/120mmHg, headaches and hypokalaemia. Suspecting secondary hypertension, she underwent several tests. Renal ultrasound, echocardiogram and catheterisation of the aorta and renal arteries showed no abnormalities. Plasma renin activity (PRA) and plasma aldosterone (PA) levels were elevated on two occasions. Urinary vanillylmandelic acid and plasma TSH, free T4 and T3 levels were normal. She was discharged from hospital on angiotensin-converting enzyme inhibitors and calcium channel blockers, but did not return for follow-up.
At 19 years of age, she consulted another hospital for hypertension and was eight weeks pregnant, for which she was hospitalised in intensive care. Good foetal health, BP 200/110mmHg and hypokalaemia were determined, and treatment with clonidine and alpha methyl dopa was started. Renal ultrasound showed a regular nodular formation of 45mm in diameter in the lower pole of the left kidney, ultrasonographically compatible with angiomyolipoma. PRA and AP levels were elevated. She continued on outpatient treatment with labetalol and nifedipine. At 19 weeks' gestation she was admitted to the emergency room with a diagnosis of missed abortion, and a curettage was performed. Four days later she requested voluntary discharge and did not return for follow-up.
Two years later, while on medication with enalapril, losartan and amlodipine, she was admitted to our hospital ward with occipital headache and muscle weakness of several days' duration. BP was found to be 220/140mmHg. Initial studies showed hypokalaemia of 2mEq/l, plasma creatinine of 0.6mg/dl and plasma urea of 25mg/dl. Renal ultrasound showed a solid nodular image, corroborated by contrasted abdominal computed tomography, where a voluminous space-occupying formation was observed, solid, in the interpolar sector and lower pole of the left kidney, 65mm in diameter, hypovascularised. The Doppler of the renal arteries and the echocardiogram showed no alterations.
Given the presumptive diagnosis of HTN secondary to renal tumour, due to high renin levels, and having ruled out other secondary causes of HTN in previous studies, it was decided to perform a nephrectomy of the affected kidney, having previously controlled BP with the addition of spironolactone at a dose of 100mg/day to his usual medication.
Pathological examination revealed a 5.5x4.5cm encapsulated tumour, haemorrhagic in appearance, with whitish fibrous areas. Microscopically, the tumour lesion was found to consist of medium-sized cells, with medium-sized, vesicular nuclei, with irregular chromatin, some with inconspicuous nucleoli and eosinophilic cytoplasm, others with clear cytoplasm, arranged in a diffuse pattern with extensive haemorrhage and mild mononuclear inflammatory infiltrate, without invasion of the renal capsule. No cellular atypia, mitosis or necrosis was found. The tumour cells were positive for vimentin and showed strong and diffuse positivity for CD34. Ultrastructural observation revealed cells with intracytoplasmic granules with different degrees of electrolucency, surrounded by membranes. In terms of morphology, they varied from round to elongated, acquiring some shapes with rectilinear edges, and in some of them a crystalloid rhomboid shape stood out, which at high magnification showed a zigzag structure of marked electrodensity. These findings could be linked to juxtaglomerular cell tumour (JCT), confirming the clinical suspicion.
After surgery, the patient's BP gradually decreased and antihypertensive drugs were simultaneously withdrawn, and she evolved asymptomatic, normotensive, with normal levels of plasma renin, aldosterone and serum potassium, without pharmacological treatment.
