Child with acute weakness: don’t forget the salts

Abstract

Case summaryA 10-year-old boy presented with severe progressive generalised weakness on a background of 3 days of diarrhoea and vomiting. Vital signs were normal. Peripheral neurological examination revealed grade 1–2 power in all limbs, hypotonia and hyporeflexia. Sensation was fully intact. Cranial nerve examination and speech were normal. The ECG (figure 1) and initial venous blood gas (figure 2) are shown.Figure 1ECG.Figure 2Venous blood gas.Question 1What abnormalities are present on the ECG?Peaked T waves, prolonged PR segment and loss of P waves?Shortening of the QT interval and Osborn waves (J waves)?T wave flattening/inversion, prominent U waves and long QU interval?Prolonged QT interval with multiple atrial and ventricular ectopics?Question 2How would you manage this patient’s hypokalaemia?Question 3What is the likely diagnosis?Conversion disorder.Myasthenia gravis.Periodic paralysis.Guillain-Barré syndrome.Botulism.Question 4What interventions can be considered for long-term treatment of this condition?Answers can be found on page 2.