Table 1.

Summary of clinical features and investigation results of the three siblings.

	Sibling 1 (III-2)	Sibling 2 (III-3)	Sibling 3 (III-6)
Age at presentation	11 years old	4½ years old	2½ years old
Prodrome	3 days of fever, nausea & vomiting	4 days of chesty cough, fever & rigor	5 days of fever & anorexia; 1 day of diarrhoea
Acute encephalopathy
Presenting symptoms	Blurring of vision, confusion	Impaired conscious level	Several short episodes of upward gaze
Physical signs	Hypertonia, hyper-reflexia and extensor Babinski response	Shock and acute kidney injury	Loss of vision
	Impaired vision & color vision	Right hemiparesis
	Right homonymous hemianopia	Impaired swallow
Infective screening	Normal	+ Parainfluenza I (nasopharyngeal aspirate)	+ Mycoplasma Pneumoniae titre 1:80 (blood)
	No cerebral spinal fluid (CSF) analysis	CSF – normal	+ Parainfluenza I (nasopharyngeal aspirate)
			CSF – normal
MRI brain	Bilateral symmetrical abnormal signal intensities in the lateral geniculate nuclei of the thalami, temporal lobes, midbrain and left side of the pons	Symmetrical diffuse involvement of thalami, midbrain (sparing medulla) and temporal lobes with hemorrhagic components	Diffuse hyperintensity in both temporal lobes, insula cortices, limbic systems (hippocampus and amygdala), pons, midbrain, thalami and external capsule with hemorrhagic components
Sequelae onfollow up	2½ years follow-up: Mild learning disability (LD), right homonymous hemianopia	7 years follow-up: Mild LD, clumsy, right sided hyper-reflexia but normal power	3½ years follow-up: Normal development and neurology