Causas y Diagnóstico de Hipertensión Arterial Secundaria

Causas de Hipertensión Arterial Secundaria

• Las principales causas de hipertensión arterial secundaria en pacientes jóvenes son enfermedad renal parenquimatosa, enfermedad renovascular, coartación de aorta, hiperaldosteronismo primario, feocromocitoma y apnea obstructiva del sueño 1, 2
• La enfermedad renal parenquimatosa y las anomalías estructurales renales representan del 34% al 79% de los casos de hipertensión secundaria en niños y jóvenes 2, 3
• La enfermedad renovascular está presente en 12-13% de los casos 2, 3
• La coartación de aorta es una causa importante en niños y adolescentes jóvenes 2, 3
• El hiperaldosteronismo primario es más común en adultos jóvenes con hipertensión resistente 4, 5
• La apnea obstructiva del sueño tiene una prevalencia del 25-50% en pacientes con hipertensión resistente 4

Evaluación y Diagnóstico

• En pacientes jóvenes con hipertensión severa y poca historia familiar, considerar fuertemente una causa secundaria 1, 6
• La evaluación de daño a órganos diana (hipertrofia ventricular izquierda) es importante en la evaluación de sospecha de hipertensión secundaria 1, 6
• Pruebas de laboratorio básicas: función renal, electrolitos, análisis de orina 2

Factores de Riesgo y Asociaciones

• La exposición al plomo está asociada con presión arterial más alta en estudios poblacionales 3
• La exposición al cadmio está vinculada a niveles más altos de presión arterial y desarrollo de hipertensión 3
• El consumo de alcohol, cafeína y nicotina pueden influir en la presión arterial 4
• Los antiinflamatorios no esteroideos pueden aumentar la presión arterial 4

Tratamiento y Prevención

• El tratamiento debe dirigirse a la causa subyacente específica, y puede incluir terapias no farmacológicas como asesoramiento dietético activo y prescripción de actividad física 1, 6
• La intervención farmacológica se reserva para niños cuya presión arterial es consistentemente muy alta, para aquellos con hipertensión secundaria sustancial, y para niños con evidencia de efectos en órganos diana como hipertrofia ventricular izquierda 1, 6

Evaluation and Management of Hypertension in Adolescents

Initial Diagnostic Confirmation

• The American Academy of Pediatrics recommends obtaining ambulatory blood pressure monitoring (ABPM) to confirm the diagnosis of hypertension in adolescents before proceeding with any laboratory or imaging studies 7, 8
• True hypertension requires mean systolic and diastolic BP ≥95th percentile on ABPM with BP load ≥25% 9

History and Physical Examination

• A targeted history and physical examination should be obtained to identify secondary causes of hypertension, including perinatal history, family history, medication/substance use, and symptoms suggesting secondary causes 7, 10
• Physical examination findings, such as femoral pulse delay or blood pressure differential between arms and legs, can indicate coarctation of the aorta 7, 8, 10

Laboratory and Imaging Evaluation

• Urinalysis, serum creatinine and electrolytes, lipid panel, and fasting glucose should be obtained in all confirmed cases of hypertension 7, 8, 10, 11
• Renal ultrasound with Doppler is the first-line imaging to assess for structural renal abnormalities and renovascular disease 7, 9
• Echocardiography should be performed if considering pharmacologic treatment to assess for left ventricular hypertrophy 12, 9

Management Approach

• The American Academy of Pediatrics recommends lifestyle modifications, including a DASH-type diet, moderate to vigorous physical activity, and avoidance of alcohol, caffeine, and nicotine 7, 8, 10, 12
• Pharmacologic therapy should be initiated if stage 2 hypertension is confirmed, left ventricular hypertrophy is present, or symptomatic hypertension exists 7, 12
• First-line agents for pharmacologic therapy include ACE inhibitors, ARBs, long-acting calcium channel blockers, or thiazide diuretics 12
• The goal blood pressure is <90th percentile and <130/80 mmHg in adolescents ≥13 years 12

Follow-Up Schedule

• Follow-up should occur every 4-6 weeks if on antihypertensive medications until blood pressure is controlled, and every 3-6 months if managed with lifestyle modifications alone 7, 10

Investigations for Young Hypertensive Patients

Initial Essential Laboratory Tests

• The American Heart Association recommends urinalysis and urine protein assessment to detect renal parenchymal disease, which accounts for 34-79% of secondary hypertension in young patients 13
• The American College of Cardiology recommends serum creatinine and estimated GFR to evaluate kidney function, with a strength of evidence level of B 13, 14
• Serum electrolytes (sodium and potassium) should be assessed as hypokalemia suggests primary aldosteronism, though most patients with aldosteronism are normokalemic 13, 14
• A lipid profile and fasting glucose or HbA1c should be performed for cardiovascular risk stratification, as recommended by the American Heart Association 13, 14
• A 12-lead ECG should be performed to detect left ventricular hypertrophy (target organ damage), with a Class IIa recommendation from the European Society of Cardiology 13, 14

Screening for Specific Secondary Causes

Primary Aldosteronism Screening

• The European Society of Cardiology recommends measuring aldosterone-to-renin ratio (ARR) in all young hypertensive patients, as primary aldosteronism affects 5-20% of hypertensive individuals, with a Class IIa recommendation 15
• The 2024 ESC guidelines specifically recommend ARR screening in all adults with confirmed hypertension, with a strength of evidence level of A 15

Pheochromocytoma/Paraganglioma Screening

• The American Heart Association recommends measuring 24-hour urinary fractionated metanephrines and catecholamines (or plasma free metanephrines) if paroxysmal hypertension, severe or resistant hypertension, adrenal mass, or family history of pheochromocytoma are present, with a strength of evidence level of B 14, 16

Cushing Syndrome Screening

• The Endocrine Society recommends screening for hypercortisolism with late-night salivary cortisol or 24-hour urinary free cortisol if clinical features suggest Cushing syndrome, such as truncal obesity, purple striae, glucose intolerance, or easy bruising, with a strength of evidence level of C 14, 16

Additional Imaging Studies

• The American College of Cardiology recommends renal ultrasound with Doppler in young adults with abnormal urinalysis, elevated creatinine, or clinical suspicion of renovascular disease, with a Class IIa recommendation 14
• Echocardiography is indicated to assess for left ventricular hypertrophy and evaluate target organ damage severity, with a strength of evidence level of B 14

Age-Specific Considerations

• For patients under age 6 years, renal ultrasound is mandatory as structural renal abnormalities are the predominant cause, with a strength of evidence level of A 13
• For patients 18-30 years, consider renovascular disease (fibromuscular dysplasia) and monogenic disorders more prominently, with a strength of evidence level of C 13