Clinical Guidance

Mucolipidosis II and mucolipidosis III / are distinct clinical disorders with different age of onset and clinical course. Although the experienced clinician observes variation within each phenotype, the phenotypic spectrum between ML II and ML III/ is discontinuous. Knowledge of these two "classic" phenotypes allows recognition of an interesting minority of intermediate clinical types in which physical growth in infancy resembles that in the ML II whereas neuromotor and speech development follow the course of ML III/.

Diagnostic Criteria

Suggestive Findings

GNPTAB-related disorders (which include the phenotypes mucolipidosis II [ML II] and mucolipidosis III/ [ML III/] and phenotypes intermediate between ML II and III/) should be suspected in individuals with the following age-related and findings and supportive findings .

Clinical Findings

ML II – Neonatal period

• Small to low-normal anthropometric measurements for gestational age

Management Guidelines

Evaluations Following Initial Diagnosis

To establish the extent of disease and needs of an individual diagnosed with a GNPTAB-related disorder, the evaluations for mucolipidosis II / mucolipidosis III/ summarized in this section (if not performed as part of the evaluation that led to the diagnosis) are recommended.

Mucolipidosis II

Surveillance Guidelines

Mucolipidosis II. Infants and toddlers with ML II and their families benefit from outpatient follow-up visits approximately every three months. Subsequently throughout early childhood, two outpatient visits per year may be adequate until cardiac and respiratory monitoring need to be more frequent. Mucolipidosis III/. Young children with ML III/ and their families benefit from outpatient clinic visits about twice a year. From age six years similar follow-up visits are recommended on a yearly basis unless bone pain and/or deteriorating ambulation become major handicaps and require closer orthopedic follow up and/or cardiac and respiratory monitoring need to be more frequent.