Table 1.

Clinical features of the three cases of COQ7 pathogenic variants reported in literature

	Freyer et al	Wang et al	Index patient
Ancestry	Syrian	–	Chinese
Parents	Consanguineous	Consanguineous	Nonconsanguineous
Antenatal	Oligohydramnios, fetal lung hypoplasia, growth retardation	Gestational diabetes	Oligohydramnios, growth retardation, fetal cardiomegaly
Gestational age	Full term	37 wk	33 wk
Respiratory	Lung hypoplasia with persistent pulmonary hypertension of newborn	–	Central hypoventilation
Renal	Renal dysfunction with small dysplastic kidneys with impaired cortical differentiation (resolved upon follow‐up)	–	Multiple renal cysts and diffuse increase in renal parenchymal echogenicity with accentuation of cortico‐medullary differentiation
Cardiovascular	Left ventricular cardiac hypertrophy (with subsequent regression), systemic hypertension	–	Severe hypertrophic cardiomyopathy with pericardial effusion, moderate tricuspid regurgitation
Growth and feeding	Postnatal growth retardation with oromotor dysfunction requiring gastrostomy	Normal	Postnatal growth retardation with oromotor dysfunction requiring tube feeding
Neurology and developmental outcome	Normal MRI brain	Normal MRI brain	MRI brain showed subdural hematoma, basal ganglial and thalami hypodensities with abnormal lactate peak
	Distal contractures since birth with progressive peripheral sensorimotor polyneuropathy, axonal, and demyelinating type	Generalized muscle wasting, more prominent in the legs, also affecting temporalis muscle	Generalized hypotonia with progressive myopathy clinically
	Mild learning difficulties at 9 y old, never learned to stand or walk independently	Normal early developmental milestones, followed by language delay since 14 mo, progressive motor regression since second year and became wheelchair bound at 3	Global developmental delay with developmental age below 3 mo across all domains at 1 y
Hearing	Combined sensorineural and conduction hearing impairment	Bilateral low frequency sensorineural hearing loss	Bilateral profound hearing impairment in range of 2‐4 Hz
Vision	Visual dysfunction	–	Lack of visual following
Respiratory chain enzyme activities	Complex I + III and IV deficiency	–	Complex II + III deficiency with normal isolated activity of complex II and complex III
COQ7 variants identified	p.(Val141Glu)	p.(Leu111Pro)	p.(Lys200Ilefs*56), p.(Arg107Trp)
Response to treatment	Dosage of CoQ10 not available	CoQ10 11.4 mg/kg twice daily	CoQ10 4 mg/kg/day since 2 mo
	Regression stalled	No obvious improvement	Stepped up to 20 mg/kg/day at 1 y
	Significant reduction in neuromuscular pain	No deterioration or worsening spasticity	No obvious response to treatment

Abbreviation: MRI, magnetic resonance imaging; y, years; mo, months.