What this trial measures

• Detailed phenotyping of the clinical course of SLC13A5 deficiency over time: general evaluationsUp to 24 months

  Conducted in patients with SLC13A5 deficiency: general appearance, HEENT, neck, chest and lungs, cardiovascular, abdomen, genitourinary, rectal, musculoskeletal, lymph nodes, extremities/skin, mental status (alertness, interaction, language (EXP) (REC)), emotional affect (calm, smiling, laughing, anxious, frowning, crying, irritable, screaming). As much information as available will also be collected from existing medical records including clinical evaluations, imaging studies and neuropsychological and motor function evaluations.

• Detailed phenotyping of the clinical course of SLC13A5 deficiency over time: vitals and biometrics evaluationsUp to 24 months

  Conducted in patients with SLC13A5 deficiency: height (cm), weight (kg), blood pressure (systolic and diastolic), temperature (c), heart rate (beats/minute), respiratory rate (breaths/minute), and head circumference (cm). As much information as available will also be collected from existing medical records including clinical evaluations, imaging studies and neuropsychological and motor function evaluations.

• Detailed phenotyping of the clinical course of SLC13A5 deficiency over time: neurologic evaluationUp to 24 months

  Conducted in patients with SLC13A5 deficiency: motor, motor stability, muscle bulk, paresis, sensation, reflexes, coordination, gait, and autonomic. As much information as available will also be collected from existing medical records including clinical evaluations, imaging studies and neuropsychological and motor function evaluations.

• Detailed phenotyping of the clinical course of SLC13A5 deficiency over time: dental evaluationsUp to 24 months

  Conducted in patients with SLC13A5 deficiency: baseline pain assessment from a scale of 0-10 (0 being no pain and 10 being highest pain), temperature pain assessment for cold from a scale of 0-10 (0 being no pain and 10 being highest pain), temperate pain assessment for hot from a scale of 0-10 (0 being no pain and 10 being highest pain), toothpaste use (type and frequency), and Fluoride treatments. As much information as available will also be collected from existing medical records including clinical evaluations, imaging studies and neuropsychological and motor function evaluations.

• Detailed phenotyping of the clinical course of SLC13A5 deficiency over time: clinical and research laboratory studiesUp to 24 months

  Conducted in patients with SLC13A5 deficiency: Clinical: ammonia, amylase, CKMB, GGT, lactate, lipase, PT/PTT, vitamin d 25-oh, CBC with differential, comprehensive MET panel, lipid panel with calculated LDL, and urine studies (calcium/creatinine ratio, spot ph, spot citrate concentration, citrate/creatinine ratio). Research: Citrate and metabolomics. As much information as available will also be collected from existing medical records including clinical evaluations, imaging studies and neuropsychological and motor function evaluations.

• Detailed phenotyping of the clinical course of SLC13A5 deficiency over time: electroencephalogram (EEG)Up to 24 months

  Conducted in patients with SLC13A5 deficiency: looking at the duration of EEG, if they are captured awake or asleep, and if it is abnormal. As much information as available will also be collected from existing medical records including clinical evaluations, imaging studies and neuropsychological and motor function evaluations.

• Detailed phenotyping of the clinical course of SLC13A5 deficiency over time: scoring of movement disorder and SLC13A5 deficiency symptom scalesUp to 24 months

  Conducted in patients with SLC13A5 deficiency: using scale titled "Movement Exam for SLC13A5 Natural History Study". Assessing typical gait, standing in natural position, sitting on chair, head control, attempt to vocalize, speech quality, speech content, ability to grab items, and ability to draw. Symptom scales consist of chorea, dystonia, ataxia, myoclonus, tremor, hypokinetic-rigid syndrome, and tic. As much information as available will also be collected from existing medical records including clinical evaluations, imaging studies and neuropsychological and motor function evaluations.

• Neurodevelopmental profile of SLC13A5 deficiency as measured using Mullen Scales of Early LearningUp to 24 months

  Consists of a gross-motor scale and four cognitive scales: visual reception, fine motor, receptive language, and expressive language. T-Scores (mean of 50 and a standard deviation of 10) are given for individual scales, and an optional Early Learning Composite standard score (mean of 100 and a standard deviation of 15) serves as an overall estimate of cognitive functioning. This is based on child's age and there are no higher or lower scores that indicate a better or worse outcome. Developmental assessment at baseline and longitudinally, if age and ability-appropriate.

• Neurodevelopmental profile of SLC13A5 deficiency as measured using the Peabody Developmental Motor Scales-2Up to 24 months

  Six subtests that measure motor ability in children: reflexes, stationary, locomotion, object manipulation, grasping, and visual motor integration. The Peabody has quotients that measure a child's motor ability: gross motor quotient, fine motor quotient, total motor quotient. This is based on child's age and there are no higher or lower scores that indicate a better or worse outcome. Developmental assessment at baseline and longitudinally, if age and ability-appropriate.

• Neurodevelopmental profile of SLC13A5 deficiency as measured using the Vineland-III Adaptive Behavior ScaleUp to 24 months

  Vineland is a semi-structured interview that assesses adaptive behavior in several domains, summarized by the Adaptive Behavior Composite (ABC) standard score. ABC standard scores may range from 20 to 160, with a population mean of 100 and a standard deviation of 15. There are no higher or lower scores that indicate a better or worse outcome. Developmental assessment at baseline and longitudinally, if age and ability-appropriate. Additionally, Vineland-III Adaptive Behavior Scale questionnaire will be included in the remote assessment interview.

• Seizure burden and semiology as measured using the Seizure Global Impression of ChangeUp to 24 months

  Assessing the status of the patient's overall condition using a scale ranging from very much improved, much improved, slightly improved, no change, slightly worse, much worse, very much worse. Assessing the average number of participants' seizures on a scale of decreased, stayed the same, increased. Assessing the average duration of the participants' seizures on a scale of decreased, stayed the same, increased. Caregiver will be asked to maintain a seizure diary throughout the study and seizure burden will be assessed at in-person and remote assessments.