眼皮膚白皮症

Infantile nystagmus syndrome is classified into two main categories: idiopathic infantile nystagmus, in which no obvious structural or functional abnormalities of the eyes are present and infantile nystagmus associated with ocular pathologies (sensory defect nystagmus). In the latter, a defect located in the visual pathway but anterior to the lateral geniculate nucleus is responsible for the nystagmus, e.g., pathologies of the anterior segment, retinal diseases or optic neuropathies. Furthermore, oculocutaneous or ocular albinism is a common cause of infantile nystagmus syndrome. Acquired nystagmus of neurological origin also occurs in early childhood, e.g., in the context of complex hereditary malformations of the central nervous system, syndromic disorders or tumor-related diseases. This article provides an overview of the differential diagnosis of infantile nystagmus. It covers important aspects of the medical history and clinical examination that help to assign patients to the appropriate subgroups and to assess the urgency of further, possibly interdisciplinary, investigations.

PURPOSE: To characterize perception of Haidinger's brushes (HB) in individuals with albinism, in whom reduced macular pigment and abnormal foveal/Henle-fiber morphology may alter polarization sensitivity. METHODS: Three participants with oculocutaneous albinism (aged 19-29 years; two with nystagmus) viewed 468-nm polarized/unpolarized LED stimuli in a custom polarimetry device. Six randomized conditions varied polarization (0%, 20%, 50%, 100%) and polarizer rotation speed (2.3, 2.7, and 2.95 revolutions per second, rps); each tested eye completed three repetitions per condition. On each trial, participants reported percept presence/absence and qualitatively described any experienced percept. RESULTS: At 100% polarization, perception occurred at 2.7 and 2.95 rps in all tested eyes but was absent at 2.3 rps. At 50% polarization/2.7 rps, P1 and P2 reported blurred perception in both eyes, whereas P3 reported none. No responses occurred at 20% or 0% polarization. Reported patterns were consistently asymmetric, peripheral, flickering/wavy, and unlike the classical central bowtie. CONCLUSIONS: Individuals with albinism can perceive polarization-dependent entoptic phenomena, but the percept may be qualitatively altered. The findings suggest residual macular-pigment-related dichroism but do not isolate its retinal, corneal, or neural determinants. Quantitative studies with macular pigment optical density (MPOD) mapping, optical coherence tomography metrics of the Henle fiber layer (OCT-HFL), corneal polarimetry, and temporal-sensitivity testing are needed.

Hermansky-Pudlak syndrome (HPS) is a rare inherited multisystem condition characterized by oculocutaneous albinism, bleeding diathesis, and subtype-specific systemic complications, including pulmonary fibrosis and granulomatous colitis. Early diagnosis is essential because pulmonary involvement, particularly in HPS type 4, may be life-threatening. We report a boy who was first referred for ophthalmologic evaluation at seven weeks of age due to generalized hypopigmentation and congenital nystagmus. Examination revealed marked iris translucency, diffuse fundus hypopigmentation with prominent choroidal vasculature, pendular horizontal nystagmus, suspected esotropia, and hyperopia. Genetic testing was initiated at five months of age to determine the underlying cause of the oculocutaneous albinism, including possible syndromic causes. It identified biallelic variants in the HPS4 gene, confirming Hermansky-Pudlak syndrome type 4 at eight months of age. Multidisciplinary evaluation, including hematologic and pulmonary baseline assessments, was subsequently initiated. At the latest follow-up, at two years and five months of age, the patient remained clinically stable without evidence of pulmonary or gastrointestinal complications. Visual rehabilitation and early developmental support were implemented. This case underscores the critical role of early ophthalmologic recognition of oculocutaneous albinism in establishing the diagnosis of Hermansky-Pudlak syndrome. Timely genetic confirmation enables structured surveillance for pulmonary fibrosis and other systemic complications associated with HPS type 4.

Oculocutaneous albinism (OCA) is characterised by hypopigmentation of the skin, hair and eyes. Developmental delay is not a commonly reported feature in OCA. A female toddler was diagnosed with OCA, global developmental delay, hypotonia and congenital heart disease.Given the coexisting neurodevelopmental and cardiac abnormalities, chromosomal microarray (CMA) analysis was performed, which revealed a homozygous deletion at chromosome 11q14.3 involving the TYR, GRM5 and NOX4 genes. Parental segregation analysis using CMA demonstrated heterozygous deletions in both parents, with the proband's homozygous deletion resulting from overlapping parental deletions.To our knowledge, this is the first reported case of a large TYR gene deletion causing OCA, thereby expanding the mutational spectrum associated with the disorder. This case highlights the importance of detailed phenotyping and appropriate selection of genetic testing. Additionally, parental segregation analysis plays a crucial role in improving diagnostic accuracy and in understanding genotype-phenotype correlations.

This study documents unusual pigmentation patterns in marine fishes from Spanish coastal waters and provides a global synthesis of published records of ambicolouration in wild flatfishes. A mixed pigmentation anomaly was recorded in Diplodus sargus (Sparidae), severe hypopigmentation compatible with oculocutaneous albinism was documented in Halobatrachus didactylus (Batrachoididae), and near-complete ambicolouration was observed in Solea senegalensis (Soleidae). Three additional unusual pigmentation patterns involving Labrus bergylta (Labridae) and D. sargus were documented photographically during underwater observations and are regarded as putative pigmentation anomalies because natural colour variation and physiological colour change cannot be excluded. The specimens were obtained opportunistically through fishery bycatch, scientific surveys and underwater observations conducted in Galicia and Andalusia between 2025 and 2026. DNA barcoding confirmed the species identity of the three collected specimens. The discovery of an ambicoloured Solea senegalensis prompted a review of this condition in wild flatfishes worldwide. The literature review identified 100 studies reporting ambicolouration in 79 wild flatfish species from 10 of the 19 recognized families. Pleuronectidae and Paralichthyidae contained the largest numbers and proportions of species with published records, although these patterns may be influenced by uneven research and reporting effort. Pigmentation anomalies, although uncommon in nature, have been associated with genetic, developmental or environmental processes, but their environmental significance cannot be determined from opportunistic records alone. Standardized long-term monitoring accompanied by population and environmental data would be required to assess their potential value in ecosystem assessment.