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Emcitate (tiratricol)

MCT8 deficiency

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78 sources

Product information and disease descriptionPlace of product in therapyDisease description

Clinical presentation - signs and symptoms

10 evidence topics · 7 sources

Onset and early presentation

“Individuals with MCT8 deficiency are typically born following an uneventful pregnancy and have normal weight and length for gestational age. In many cases, the first presentation to a healthcare professional occurs around 4 months of age, with signs of gross developmental delay, general failure to thrive, and severe muscular hypotonia” (opens the source at this quote in a new tab)

Cognitive and developmental symptoms: intellectual disability, walking, and speech

“Most affected males have profound-to-severe intellectual disability with no acquisition of walking; most affected males never speak or may develop only garbled sounds secondary to severely dysarthric speech. Less frequently, affected males have mild-to-moderate intellectual disability, and develop the ability to walk (with or without aid) and use of language allowing academic learning with aid.” (opens the source at this quote in a new tab)

Developmental milestones: Japanese nationwide survey
FindingParticipants with finding (evaluable denominator in label)
Completion of head control, n = 28“7 (25 %)”
Able to keep sitting, n = 28“0 (0 %)”
Able to speak a word, n = 27“0 (0 %)”
Abnormal sleep rhythm, n = 27“9 (33 %)”
Feeding difficulty, n = 26“4 (15 %)”
Motor symptoms: hypotonia, dystonia, and bradykinesia

“All three patients exhibit profound psychomotor delay, with axial hypotonia, limb dystonia, and bradykinesia as consistent features.” (opens the source at this quote in a new tab)

Motor symptoms: truncal hypotonia and paroxysmal dyskinesias

“Truncal hypotonia, a main feature of AHDS, persists into adulthood.” (opens the source at this quote in a new tab)

“It is common for affected males to experience purposeless movements described as dystonic and/or athetoid and characteristic paroxysms or kinesigenic dyskinesias” (opens the source at this quote in a new tab)

“These can be triggered by somatosensory stimuli, including changing clothes or diaper, or lifting the affected child.” (opens the source at this quote in a new tab)

Seizures

“Patients with MCT8 deficiency may be predisposed to seizures, which predominantly manifest as generalized, absence-like episodes without an overt motor component.” (opens the source at this quote in a new tab)

“Seizures in patients with MCT8 deficiency are often reported to be refractory or poorly controlled” (opens the source at this quote in a new tab)

Peripheral thyrotoxic symptoms

“Peripheral dysthyroidism can be expressed as cold intolerance, sweating, intestinal transit disorders, tachycardia, high blood pressure, and sleep disorders.” (opens the source at this quote in a new tab)

Cardiovascular and nutritional manifestations: international natural-history cohort
ManifestationAffected participants and evaluable denominator
Elevated systolic blood pressure above the 90th percentile“25 (53%) of 47”
Premature atrial contractions“34 (76%) of 45”
Resting tachycardia“20 (31%) of 64”
Underweight“59 (71%) of 83”
Biochemical and neuroimaging findings: international natural-history cohort

“Tri-iodothyronine concentrations were above the age-specific upper limit in 96 (95%) of 101 patients and free thyroxine concentrations were below the age-specific lower limit in 94 (89%) of 106 patients.” (opens the source at this quote in a new tab)

“The most consistent MRI finding was a global delay in myelination, which occurred in 13 (100%) of 13 patients.” (opens the source at this quote in a new tab)

Phenotypic spectrum in an exome-sequenced United States cohort

“In a cohort of 122 individuals with SLC16A2 variants, we identified 68 cases with likely pathogenic/pathogenic (L/PATH) variants and 54 individuals with variants of uncertain significance (VUSs).” (opens the source at this quote in a new tab)

“Common HPO terms included global developmental delay (79/108, 73.1%), generalized hypotonia (40/108, 37.0%), and delayed speech and language development (29/108, 26.9%).” (opens the source at this quote in a new tab)

“HPO terms related to thyroid function and/or hormone levels were not commonly reported, with hypothyroidism the most frequently reported term, seen in six individuals.” (opens the source at this quote in a new tab)