Paediatrics: Hypertension - causes and features

2021-03-03 12:00 AM

High body mass index, excessive salt intake, lack of exercise, and family history may be underlying predisposing factors.

Hypertension: causes and features

Causes of hypertension

Primary (essential) hypertension

This is a diagnosis of exclusion. High body mass index, excessive salt intake, lack of exercise, and family history may be underlying predisposing factors

Secondary hypertension

  • Renal (commonest cause in-hospital referral practice):

o chronic renal parenchymal disease (reflux/scarring)

o polycystic kidney disease

o obstructive uropathy

o acute nephritis

o chronic renal failure

  • Vascular:

o umbilical arterial/venous catheters

o renal artery stenosis

o renal vein thrombosis

o coarctation of the aorta

o vasculitis

  • Endocrine:

o congenital adrenal hyperplasia

o hyperthyroidism

o increased steroids (iatrogenic or endogenous)

o phaeochromocytoma (BP intermittently raised)

o hyperaldosteronism

  • Trauma
  • Neurological:

o 2° to pain

o raised intracranial hypertension

  • Tumours:

o neuroblastoma

o Wilms

  • Medication:

o steroids

o aminophylline/caffeine

o oral contraceptive pill

o erythropoietin

o calcineurin inhibitors; decongestants

o amphetamines; cocaine

  • Others:

      bronchopulmonary dysplasia

      ECMO

      ‘white-coat’ hypertension

Clinical features

Most are asymptomatic.

Infants

  • Vomiting.
  • Failure to thrive (rare).
  • Congestive cardiac failure/respiratory distress (in newborns).

Children

  • Headache/nausea and vomiting.
  • Visual symptoms.
  • Irritable/tired.
  • Bell’s palsy.
  • Epistaxis.
  • Growth failure.
  • Fits.
  • Altered consciousness.

Examination

  • Check fundi.
  •  Feel abdomen for abdominal masses.
  • Listen for renal bruits.
  • Feel femoral pulses and compare to radial/brachial pulses (to exclude
  • coarctation) and check BP in all 4 limbs.
  • Examination of the heart.

Investigations

 

As the cause is more likely with severe hypertension. Treatment and investigations may need to proceed together.

  • Urine:
  •  urinalysis, microscopy, and culture;
  • vanillylmandelic acid (VMA): creatinine ratio;
  • steroid profile and toxicology.
  • Blood tests:

     - FBC;

      - U&E and creatinine;

     -  Bicarbonate, calcium, phosphate, albumin;

      - Plasma renin and aldosterone.

  • CXR and ECG.
  • ECG.
  • The US of urinary tract + Doppler if renal artery stenosis suspected.
  • Further imaging will depend upon suspected cause and ultrasound
  • findings, e.g. DMSA, CT scan, arteriogram.
  • Specialized tests, e.g. for phaeochromocytoma.