The potential role of propranolol in incontinentia pigmenti

Incontinentia pigmenti and the eye

PURPOSE OF REVIEW

Incontinentia pigmenti (IP) is a rare X-linked dominant phakomatosis that predominately presents with dermatologic manifestations but can also cause central nervous system and ocular abnormalities. Awareness of the ocular complications of IP is crucial to identify ocular abnormalities early and prevent permanent vision loss.

RECENT FINDINGS

There have been significant recent advances in ocular diagnostic imaging in IP. Optical coherence tomography (OCT) has helped characterize outer plexiform layer abnormalities in the macula, which can help explain central vision loss in IP patients. OCT angiography (OCT-A) also identifies macular vascular changes that induce these foveal structural abnormalities and may supplement fluorescein angiography, the current standard of care to identify peripheral retinal ischemia and neovascularization for infants with IP. Additionally, recent studies have presented excellent anatomic outcomes years after laser photocoagulation to ischemic retina. Early data indicates that antivascular endothelial growth factor therapy can induce retinal revascularization, but runs the risk of late recurrent neovascularization and requires long-term monitoring.

SUMMARY

Ophthalmic imaging is evolving in the evaluation of IP and is increasingly guiding treatment modalities. A particular focus on the ocular manifestations of IP has been the ideal treatment for retinopathy in this disorder.

Uncovering incontinentia pigmenti: From DNA sequence to pathophysiology

Incontinentia pigmenti (IP) is an X-linked dominant genodermatosis. The disease is known to be caused by recurrent deletion of exons 4-10 of the Inhibitor Of Nuclear Factor Kappa B Kinase Regulatory Subunit Gamma (IKBKG) gene located at the Xq28 chromosomal region, which encodes for NEMO/IKKgamma, a regulatory protein involved in the nuclear factor kappa B (NF-κB) signaling pathway. NF-κB plays a prominent role in the modulation of cellular proliferation, apoptosis, and inflammation. IKBKG mutation that results in a loss-of-function or dysregulated NF-κB pathway contributes to the pathophysiology of IP. Aside from typical skin characteristics such as blistering rash and wart-like skin growth presented in IP patients, other clinical manifestations like central nervous system (CNS) and ocular anomalies have also been detected. To date, the clinical genotype-phenotype correlation remains unclear due to its highly variable phenotypic expressivity. Thus, genetic findings remain an essential tool in diagnosing IP, and understanding its genetic profile allows a greater possibility for personalized treatment. IP is slowly and gradually gaining attention in research, but there is much that remains to be understood. This review highlights the progress that has been made in IP including the different types of mutations detected in various populations, current diagnostic strategies, IKBKG pathophysiology, genotype-phenotype correlation, and treatment strategies, which provide insights into understanding this rare mendelian disorder.

Retinal Neovascularization in Two Patients with Incontinentia Pigmenti

Incontinentia pigmenti (IP) is a rare genodermatosis, inherited in an X-linked dominant pattern, making it generally found among women. Among several characteristics of IP are four phases of skin manifestation that tend to follow Blaschko’s lines, in addition to abnormalities of the eye, central nervous system (CNS), and teeth. Ocular involvement in IP patients can occur since birth, which can be classified into retinal or non-retinal disorders. Retinal disorders can result in detachment, which is a major ocular threat for IP patients. This article reports two IP cases with overlapped phases of skin disorders in baby girls with ocular manifestations since early life. Clinical signs and additional examination of the skin and eyes are utilized to make the diagnosis. All the features of the histopathological examination supported the diagnosis of IP, and ocular exams revealed abnormalities in the form of retinal neovascularization (RN). Although RN may resolve spontaneously, patients should be monitored for the development of other eye disorders such as visual impairment.