Perri Segal1, Ben Pode-Shakked2, Annick Raas-Rothschild3. 1. Department of Psychology, Hebrew University, Jerusalem, Israel. 2. Institute of Rare Diseases & Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel-Hashomer, Israel; The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; The Dr. Pinchas Borenstein Talpiot Medical Leadership Program, Sheba Medical Center, Tel-Hashomer, Israel. 3. Institute of Rare Diseases & Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel-Hashomer, Israel; The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel. Electronic address: Annick.Rothschild@sheba.health.gov.il.
Abstract
BACKGROUND: Mucolipidosis type IV (ML-IV) is a rare autosomal recessive lysosomal storage disorder which presents with nonspecific developmental delay. Nowadays with the use of new tools such as next generation sequencing, more ML-IV affected patients are diagnosed. Still, identifying the behavioral phenotype might be of help for early diagnosis and anticipatory guidance, as well as for counseling of the families. OBJECTIVE: Identification of the behavioral characteristics of 12 ML-IV patients, aged from 2.5 to 34 years, based on their caregivers' observations. METHODS: The information was gathered from the patients' parents using an extensive semi-structured interview especially designed for this study. Each interview lasted approximately three hours. RESULTS: Patients were uniformly described as friendly and show explicit pleasure from both social interactions and music. They all presented delays in psychomotor development, while their general health was reported as good. Parents reported that the patients present deterioration of motor and communication skills over the years. Episodes of ocular pain, with ipsilateral flushing of the face and tearing were frequently reported, as was shortening of the Achilles tendon. Since the identification of the ML-IV gene, diagnosis is made earlier in life. CONCLUSION: We suggest that ML-IV be considered in the differential diagnosis of patients with developmental delay, who present the behavioral phenotype reported here. This pattern could also be useful for the ancitipatory guidance in the care of ML-IV affected patients. Further clinical research is warranted to confirm these preliminary findings.
BACKGROUND:Mucolipidosis type IV (ML-IV) is a rare autosomal recessive lysosomal storage disorder which presents with nonspecific developmental delay. Nowadays with the use of new tools such as next generation sequencing, more ML-IV affected patients are diagnosed. Still, identifying the behavioral phenotype might be of help for early diagnosis and anticipatory guidance, as well as for counseling of the families. OBJECTIVE: Identification of the behavioral characteristics of 12 ML-IVpatients, aged from 2.5 to 34 years, based on their caregivers' observations. METHODS: The information was gathered from the patients' parents using an extensive semi-structured interview especially designed for this study. Each interview lasted approximately three hours. RESULTS:Patients were uniformly described as friendly and show explicit pleasure from both social interactions and music. They all presented delays in psychomotor development, while their general health was reported as good. Parents reported that the patients present deterioration of motor and communication skills over the years. Episodes of ocular pain, with ipsilateral flushing of the face and tearing were frequently reported, as was shortening of the Achilles tendon. Since the identification of the ML-IV gene, diagnosis is made earlier in life. CONCLUSION: We suggest that ML-IV be considered in the differential diagnosis of patients with developmental delay, who present the behavioral phenotype reported here. This pattern could also be useful for the ancitipatory guidance in the care of ML-IV affected patients. Further clinical research is warranted to confirm these preliminary findings.