Allelic heterogeneity in a patient with postzygotic MTOR-related hypomelanosis of Ito with neurodevelopmental abnormalities

A case of mosaic MTOR-associated hemimegalencephaly and hypomelanosis of Ito, died at 33 probably because of sudden unexpected death in epilepsy. Assessment of the variant allele fraction (VAF) in different tissues postmortem showed high variability not correlated with clinical features, representing the most detailed assessment of VAFs in different tissues to date.

Patterned cutaneous hypopigmentation phenotype characterization: A retrospective study in 106 children

BACKGROUND

Cutaneous patterned hypopigmentation's phenotype is highly variable and may be associated with extracutaneous anomalies.

OBJECTIVE

We evaluated the phenotypic and clinical characteristics of patients with cutaneous patterned hypopigmentation to determine whether certain patterns were more likely to be associated with underlying anomalies.

METHODS

The charts of 106 children with cutaneous patterned hypopigmentation were reviewed retrospectively (2007-2018) at Sainte-Justine University Hospital Centre, in Montreal, Canada. Retrieved information included sex, age at diagnosis, phototype, pattern, and distribution of the cutaneous lesions and the presence of extracutaneous findings. Data were recorded on a software tool which collects and analyzes phenotypic information.

RESULTS

The predominant types of cutaneous patterned hypopigmentation were along Blaschko's lines in narrow (38.7%) and broad bands (53.8%). Mixed patterns were observed in 22.5% of children. The anterior trunk and posterior trunk were most frequently affected (69% and 56%, respectively). Extracutaneous involvement, especially neurological and developmental, was present in 28.3% of patients and was significantly associated with ≥ 4 involved body sites.

CONCLUSION

Distribution and types of cutaneous patterned hypopigmentation were not predictive of extracutaneous findings, with the exception of multiple sites involvement and possibly centrofacial location and blocklike lesions. Follow-up until school entry should help identify subtler associated extracutaneous anomalies.

Palmoplantar depigmentation in Macaca fascicularis following Blaschko linear pattern

Hypomelanosis of Ito is a rare neurocutaneous syndrome, characterized by streaks and swirls of hypopigmentation arranged in a Blaschkoid pattern. Other associated anomalies are observed. We report a case of a male cynomolgus monkey (Macaca fascicularis) who presented the characteristic of hypomelanosis of Ito with palmoplantar involvement and polythelia.

A case of hypomelanosis of Ito accompanied by unilateral abnormal limb overgrowth and delayed speech

Hypomelanosis of Ito (HI) is characterized by unilateral or bilateral hypopigmented skin lesions and usually presents as a multisystemic disorder. Skin lesions may develop in different textures, such as linear, whorled, or patchy, and are often accompanied by abnormalities of the central nervous system, skeletal system, eyes, and teeth. HI is associated with sporadic gene mutations but not gender. Presentation of the current case may be of use in reminding practitioners of the common extracutaneous findings of HI, along with some rare manifestations, such as delayed speech and asymmetric limb growth.

Hypomelanosis of Ito with an unusual pulmonary abnormality in an infant

Hypomelanosis of Ito (HI) is a neurocutaneous syndrome characterized by hypopigmented cutaneous lesions and extracutaneous manifestations frequently affecting the nervous system and the musculoskeletal system. Dysmorphic features, dental, ophthalmic, gastrointestinal, cardiac, and renal abnormalities are described in a minority of patients. The authors describe a 4-month-old infant having HI with unusual pulmonary hypoplasia that has not been reported so far.

Hemimegalencephaly in a patient with coexisting trisomy 21 and hypomelanosis of Ito

A male infant with trisomy 21 simultaneously showed clinical features of hypomelanosis of Ito and hemimegalencephaly, with related intractable epileptic seizures. The epileptic seizures were refractory to conventional antiepileptic drugs and persisted until the patient underwent functional hemispherotomy. It is well known that patients with hypomelanosis of Ito may also have cortical dysplasia and hemimegalencephaly and that approximately half of these patients have chromosomal abnormalities. However, to our knowledge, there is no previous report of a patient with trisomy 21 associated with hemimegalencephaly. Here, we describe a rare case of coexisting trisomy 21 and hypomelanosis of Ito, associated with hemimegalencephaly.