Deep phenotypic characterization of the retinal dystrophy in patients with RNU4ATAC-associated Roifman syndrome

PURPOSE

To characterize the retinal phenotype in RNU4ATAC-associated Roifman syndrome.

METHODS

Ten patients (including 8 males) with molecularly confirmed Roifman syndrome underwent detailed ophthalmologic evaluation including fundus imaging, fundus autofluorescence (FAF) imaging, spectral-domain optical coherence tomography (SD-OCT), and electroretinography (ERG). Six patients had follow-up eye exams. All patients also underwent comprehensive examination for features of extra-retinal Roifman syndrome.

RESULTS

All patients had biallelic RNU4ATAC variants. Nyctalopia was common (7/10). Visual acuity at presentation ranged from 20/20 to 20/200 (Age Range: 5-41 years). Retinal exam revealed features of generalized retinopathy with mid-peripheral pigment epithelial changes. A para or peri-foveal ring of hyper-autofluorescence was the commonest FAF abnormality noted (6/8). The SD-OCT demonstrated relative preservation of the foveal ellipsoid zone in six cases; associated features included cystoid changes (5/10) and posterior staphyloma (3/10). The ERG was abnormal in all patients; nine showed generalized rod-cone dystrophy, whilst one patient with sectoral retinal involvement only had isolated rod dystrophy (20 years old). On follow-up examination (Mean duration: 8.16 years), progressive loss of visual acuity (2/6), mid-peripheral retinal atrophy (3/6) or shortening of ellipsoid zone width (1/6) were observed.

CONCLUSION

This study has characterized the retinal phenotype in RNU4ATAC-associated Roifman syndrome. Retinal involvement is universal, early-onset, and overall, the retinal and FAF features are consistent with rod-cone degeneration that is slowly progressive over time. The sub-foveal retinal ultrastructure is relatively preserved in majority of patients. Phenotypic variability independent of age exists, and more study of allelic- and sex-based determinants of disease severity are necessary.

Lung histopathology evaluation of an X-MAID patient with a novel mutation in MSN

Background: The cell cytoskeleton is regulated by the ezrin-radixin-moesin (ERM) family of proteins, forming links between transmembrane proteins and the underlying actin cytoskeleton. Phosphorylation and activation of these proteins enable interactions with partners critically involved in shape regulation, such as actin filaments, transmembrane proteins, and scaffolding proteins. The MSN gene encodes moesin, which is ubiquitously expressed in lungs, spleen, kidney, endothelial cells of vessels, lymphocytes, and neutrophils. Deficiency or dysregulation of moesin, called X-linked moesin-associated immunodeficiency (X-MAID), is characterized by severe leukopenia affecting T cells, B cells, and neutrophils. To date, the clinical picture of patients with X-MAID is variable. Aim: We describe the presentation, immune-workup, and lung histopathology findings of a young male patient with X-MAID and multi-organ involvement, whose severe pulmonary vein stenosis necessitated a double lung transplant. Methods: A thorough review of the patient’s chart was performed. Results: The patient presented with a history of recurrent respiratory tract infections, oral thrush, and 3 major bacterial infections requiring admission and antibiotic therapy. His immune evaluation was remarkable for low T cells, and normal numbers of B and NK cells. At age 4 years he underwent a double lung transplant due to severe pulmonary vein stenosis, and pulmonary hypertension, developing chronic kidney injury post-transplant. Clinical trio whole exome sequencing revealed a novel hemizygous variant in the MSN gene (c.278dupT; p.L93FfsX21), predicted to cause loss-of-function in moesin. Histologic evaluation of the lung tissue before transplantation identified profound abnormalities in alveoli formation. Conclusion: Patients with moesin deficiency may present during infancy or childhood with a severe form of the disease, including combined immunodeficiency with lymphopenia and neutropenia, while adults may have a milder clinical picture. The novel MSN mutation described here adds to the known spectrum of disease and highlights the non-redundant functions of moesin, particularly in the lung. Statement of Novelty: We report the first lung histopathological description of an X-MAID case, in a pediatric patient with recurrent infections, cytopenia, and autoimmunity who underwent a double lung transplant.

Association of cerebral activity with MRI scans in infants with neonatal encephalopathy undergoing therapeutic hypothermia

We aimed to correlate amplitude-integrated EEG (aEEG) in neonatal hypoxic ischemic encephalopathy (HIE) with early magnetic resonance imaging (MRI). In this retrospective study, 32 neonates over 35 weeks' gestation with moderate/severe HIE who were treated with hypothermia were included. Early MRI scans and daily aEEG background were categorized to mild/normal, moderate, and severely abnormal. Time to sleep cycling was noted on aEEG. Mantel-Haenszel test for trends was used to explore associations between aEEG and MRI and outcome. LOESS regression was used for exploring the association of cycling with MRI scores. MRI was normal/mildly abnormal in 20 (63%) infants; in 9 (28%), moderately abnormal; and in 3 (9%), severely abnormal. Twenty-seven (84%) infants s urvived. MRI severity score was significantly associated with aEEG background score on the third and fourth days of life (p < 0.01). An increase in the MRI severity score was noted if sleep cycling appeared after the fifth day of life.Conclusions: Depressed aEEG at the third and fourth days of life and appearance of cycling beyond the fifth day of life are associated with cerebral MRI abnormalities and may be associated with increased risk of abnormal outcome. What is known: • Since therapeutic hypothermia has been shown to change long-term outcome, amplitude-integrated EEG in infants with hypoxic ischemic neonatal encephalopathy soon after birth have a limited predictive power for long-term outcome in treated infants. • Brain MRI after therapeutic hypothermia in the above infants has a significant predictive value for long-term outcome What is new: • Background amplitude-integrated EEG activity depression at the age of 3 and 4 days and delay of appearance of cycling activity are associated with worse MRI scores and may be predictive of worse long-term outcome.

Antenatal diagnosis and treatment of hypothyroid fetal goiter in an euthyroid mother: a case report and review of literature

Fetal goiter is an extremely rare complication of pregnancy. Its incidence is 1 in 40,000 deliveries. Antithyroid maternal therapy is responsible for 10-15% of fetal congenital hypothyroidism and can be considered as the most frequent underlying cause for this condition. The frequency of fetal goiter that is associated with fetal hypothyroidism and normal maternal thyroid function, as in our case, is even less frequent. Fetal goiter is associated with increased rate of perinatal complications and long-term morbidity, due to peripartum complications including labor dystocia due to its mass effect, as well as neonatal airway obstruction that may lead to hypoxic-ischemic brain injury and death. We present, in this study, a case report of late antenatal fetal goiter in an euthyroid woman and a literature review of the diagnosis and treatment of these cases.