Epilepsy in Legius syndrome: Coincidence or causation?

Legius syndrome is a rare genetic disorder, caused by heterozygous SPRED1 pathogenic variants, which shares phenotypic features with neurofibromatosis type 1 (NF1). Both conditions typically involve café-au-lait macules, axillary freckling, and macrocephaly; however, patients with NF1 are also at risk for tumors, such as optic nerve gliomas and neurofibromas. Seizure risk is known to be elevated in NF1, but there has been little study of this aspect of Legius syndrome. The reported epilepsy incidence is 3.3%-5%, well above the general population incidence of ~0.5%-1%, but the few reports in the literature have very little data regarding epilepsy phenotype. We identified two unrelated individuals, both with Legius syndrome and epilepsy, and performed thorough phenotyping. One individual's mother also had Legius syndrome and now-resolved childhood epilepsy, as well as reports of more distant relatives who also had multiple café-au-lait macules and seizures. Both probands had experienced childhood-onset focal seizures, with normal brain MRI. In one patient, EEG later showed apparently generalized epileptiform abnormalities. Based on the data from this small case series and literature review, seizure risk is increased in people with Legius syndrome, but the epilepsy prognosis appears to be generally good, with patients having either self-limited or pharmacoresponsive courses.

Neurofibroma: Case Series with Clinical Features and Recommendations.

Neurofibroma is an autosomal benign disorder. It can be localized, diffuse or invasive like plexiform neurofibroma that involves the nerves, muscle, tissues, skeleton. It represents itself as a destructive variant of neurofibroma, mostly present as orbital or periorbital neurofibroma or may be associated with autosomal dominant disease. Clinical diagnosis of neurofibromatosis (NF) according to National Institutes of Health (NIH) criteria should have more than two of the seven features including lisch nodules, cafe'- au-lait spots, plexiform neurofibroma, optic glioma, freckling, first degree relative with NF or dysplasia of cortical bones. However, proper early diagnosis is still crucial due to its various presentation such as cheek mass, painless swelling on skin, chalazion, intratracheal tumor, genital swelling or ptosis. It is reported that neurofibroma often represents as ocular or facial swelling. Here we are presenting features of neurofibroma of eight cases of patients from Civil Hospital, Karachi. These cases had main complain of overhanging skin mass mainly on orbital or periorbital region that damage the area and with poor daily activities. Multiple nodules on face and body along with them Cafe'-au-lait spots and lisch nodules were main signs. While, other signs i.e. ptosis, pterygium, telecanthus and muddy discoloration of conjunctiva need further evaluation for correlation with neurofibromatosis. Debulking surgery was planned for most of the cases but the huge disfigurement caused by overhanging skin mass and nodules made it a challenge for plastic surgeons to provide good outcomes with minimum damage. Keywords: neurofibroma; lisch nodules; ptosis; Cafe'-au-lait spot; periorbital; overhanging skin.

Genetic evaluation of 50 Turkish patients with neurofibromatosis type 1: 2 years experience of a single center.

BACKGROUND/AIM: Neurofibromatosis type 1 is an autosomal dominant neurocutaneous disorder. Clinical diagnosis is difficult in early childhood, and it is possible to miss a critical interval for tumour screening. In this study, we aimed to characterize the mutational spectrum of Turkish patients and discuss the benefits of molecular testing. MATERIAL AND METHODS: Fifty individuals from 35 unrelated families were included. Main referral reasons for genetic testing were as follows: to confirm a clinical diagnosis, to use in differential diagnosis and to evaluate first-degree family member of a known patient. Two-step process consisting of initial next generation sequencing of the NF1 gene and consequent multiplex ligation-dependent probe amplification were performed. RESULTS: We identified a total of 30 variants in 28 individuals. Variant detection rate was 56% in the entire study group and 71.4% within the index patients. Four novel variants were found. Truncating variants constituted 60% of the entire mutation spectrum. A deletion or duplication was not detected. The most common feature was cafe au lait macules in 70% of the patients, followed by focal areas of signal intensity on brain imaging (26%), cutaneous neurofibromas (24%) and axillary freckling (24%). CONCLUSIONS: Early sequencing in all suspected patients followed by deletion/duplication analysis in patients meeting clinical criteria and a case-to-case based consideration for RNA studies seems to be the effective algorithm for NF-1 diagnosis.

Aneurysms involving the coronary arteries in a neonate with neurofibromatosis 1.

Aneurysmal coronary artery disease (ACAD) has been reported rarely in patients with neurofibromatosis type 1 (NF1), mostly in adults. We report on a female newborn affected by NF1 with ACAD disclosed during investigation for an abnormal prenatal ultrasound along with a review of the previously reported cases. The proposita had multiple café-au-lait spots and had no cardiac symptoms. Echocardiography, and cardiac computed tomography angiography confirmed aneurysms on the left coronary artery, left anterior descending coronary artery, and of the sinus of Valsalva. Molecular analysis detected the pathogenic variant NM_001042492.3(NF1):c.3943C>T (p.Gln1315*). Literature findings on ACAD in NF1 indicated that this mostly occurs in males, showing predilection for the development of aneurysms at the left anterior descending coronary artery, and manifesting predominantly as acute myocardial infarction, inclusively in teenagers, though it may be also asymptomatic as in our case. This report documents the first case of ACAD in a patient with NF1 diagnosed at birth, emphasizing that its early diagnosis is essential to prevent potential life-threatening events attributable directly to coronary lesions.

Rhabdomyosarcoma as the first presentation in Neurofibromatosis Type 1: case series and review of the literature.

Neurofibromatosis Type 1 (NF1) is a neurocutaneous syndrome characterized by multiple café-au-lait macules, neurofibromas, and predisposition to malignancies, including rhabdomyosarcomas (RMS). Somatic NF1 mutations occur in RMS and other cancers, and ∼1% of patients with RMS have NF1. We describe three patients who presented prior to one year of age with RMS and were subsequently diagnosed with NF1. Compared to sporadic RMS, patients with this cancer predisposition syndrome are diagnosed younger, genitourinary sites are more common, and tumors are almost exclusively the embryonal subtype. Genomic sequencing of the tumor was initiated in one patient, and we identified a second sequence variant in NF1. The identification of molecular drivers in tumors is changing the nature of pediatric oncology by informing therapeutics targeted to specific molecular pathways and selecting patients who are likely to harbor germline variants in cancer predisposition genes who would benefit from a Medical Genetics assessment.

Fatal Retroperitoneal Bleeding in Neurofibromatosis Type 1: A Clinically Occult Complication.

ABSTRACT: Neurofibromatosis type 1 (NF1) is a common, autosomal dominant neurocutaneous syndrome. The most frequent clinical manifestations include multiple neurofibromas, café-au-lait spots, dystrophic scoliosis, benign and malignant peripheral nerve sheath tumors, and paragangliomas. Neurofibromatosis type 1 vasculopathy is a less well-recognized constellation of vascular pathologies that can cause significant medical complications in patients with NF1. A rare manifestation of this process is neurofibroma infiltration of vasculature with resultant bleeding. The case presented herein illustrates a rare example of a massive fatal hemorrhage due to disruption of a large paraspinal artery in the setting of a diffuse, infiltrative neurofibroma. This case highlights the potential of benign neurofibromas to infiltrate major blood vessels, leading to extensive bleeding and death.

A fortuitous discovery of a neurofibroma in a female patient with type 1 neurofibromatosis: a case report.

Neurofibromatosis type 1 (NF1) is a neurocutaneous condition with an autosomal dominant pattern of inheritance. This congenital disease is characterized by a wide spectrum of clinical manifestations and degree of severity. This case report describes a female patient in her early 20s who presented with a complaint of lumbosciatica-like pain evolving for several months. The condition initially escaped the attention of clinicians until a lumbar computed tomography scan and spinal magnetic resonance imaging were performed. The patient was then transferred to the general surgery department, where a clinical diagnosis of NF1 was established. The clinical manifestations were specific for this disease, including café-au-lait macules, plexiform neurofibroma, and a history of neurofibromatosis in her mother. The patient underwent surgical resection of the neurofibroma, which resulted in a favorable outcome. However, 2 years later, a new mass attached to the second lumbar spinal nerve was revealed by a follow-up computed tomography scan. Long-term and close follow-up of NF1 is required because of the high risk of malignancy and recurrence in NF1 patients.

Evaluation of the impact of the 2021 revised Neurofibromatosis type 1 diagnostic criteria on time to diagnosis.

Neurofibromatosis type 1 (NF1) has historically been diagnosed clinically based on the NIH Consensus Conference diagnostic criteria. The molecular and clinical knowledge of NF1 has subsequently improved, and an international group of experts published revised diagnostic criteria in 2021, incorporating new diagnostic criteria such as pathogenic variants in NF1. This study aimed to investigate the impact of these new diagnostic criteria on time to diagnosis (TTD) of NF1. A retrospective chart review of individuals evaluated for a diagnosis of NF1 at the Medical Genetics Clinic at Stanford Children's Health was performed. The TTD was determined by calculating the days between their first visit with a medical geneticist for NF1 and the date they would have received a diagnosis based on the previous NF1 diagnostic criteria and the 2021 updated diagnostic criteria. The revised diagnostic criteria for NF1 decreased TTD. The mean difference in TTD was 113 days shorter for the new criteria (p-value = 1.306x-05 ). This study highlights that the revised 2021 NF1 diagnostic criteria can decrease the TTD. The addition of a heterozygous pathogenic variant in NF1 as a criterion was the change that decreased TTD.

Large, linear pigmentation anomaly: an unusual dyspigmentation case.

Segmental pigmentation anomalies can be further divided into segmental pigmentation disorder (SPD) complex and café-au-lait macules (CALMs). Both are congenital skin conditions characterized by hyper- or hypopigmentation. Segmental pigmentation disorder is a rare entity, whereas CALMs are common skin lesions that may be associated with various genetic conditions, especially when several are present and the patient has other indicators of a genetic abnormality. When the CALM is segmental, segmental neurofibromatosis (type V) may be considered in the differential diagnosis. Herein we present a 48-year-old woman with a history of malignant melanoma who presented with a large, linear, hyperpigmented patch on her shoulder and arm, present since around birth. The differential diagnosis consisted of CALM versus hypermelanosis (a subtype of SPD). Given a family history of a similar lesion, in addition to a personal and family history of melanoma and internal cancers, a hereditary cancer panel was completed demonstrating genetic variance of uncertain significance. This case brings attention to a rare dyspigmentation disorder and questions a possible association with melanoma.

Neurofibromatosis tipo 1. Más allá de las manchas café con leche: ¿es necesario actualizar criterios? / Neurofibromatosis type 1. Beyond to café-au-lait spots: necessary update criteria?

Neurofibromatosis type 1 (NF1) is the most common neurocutaneous syndrome. Diagnosis is based on clinical findings that meets the criteria developed by the NIH in 1997, which remain highly sensitive and specific in adults, but not in children, in which the manifestations vary with age. In children under 2 years in the pretumoral stage with a negative family history, it would be useful to have additional clinical diagnostic criteria. Genetic testing is not widely available and although café-au-lait spots remain the cardinal and most frequent clinical sign, they cannot make the diagnosis of NF-1 on their own. (AU)

Use of Reflectance Confocal Microscopy to Predict Treatment Efficacy in Café Au Lait Macules.

BACKGROUND: Multiple lasers have been used for the treatment of café au lait macules (CALMs) with various results. Objective tools to predict therapeutic efficacy of CALMs treatment is lacking. OBJECTIVE: To determine whether reflectance confocal microscopy (RCM) characteristics correlate with CALMs response to laser treatment. MATERIALS AND METHODS: All CAMLs underwent RCM examination of length and density of dermal papillae followed by 3 sessions of Q-switched alexandrite laser (QSAL). A visual analog scale was used to assess clinical treatment efficacy. RESULTS: Forty-three patients were included, 22 had CALMs with irregular borders and 21 with smooth borders. Café au lait macules with irregular border had shorter rete pegs and less papillae (p < .05) on RCM compared with smooth border CAMLs and responded better to QSAL treatment (2.32 vs 1.10). CONCLUSION: Reflectance confocal microscopy measurement of length and density of papillae were inversely correlated with treatment response. Reflectance confocal microscopy may be a useful tool to predict CALMs response to laser treatment.

Implications of mosaicism in variant interpretation: A case of a de novo homozygous NF1 variant.

Neurofibromatosis type 1 is a common multisystem autosomal dominant syndrome caused by pathogenic heterozygous variants in the neurofibromin gene (NF1). It is associated with a substantially increased cancer risk. Mosaicism for NF1 has been clinically well-established for "second hit" variants in skin lesions and tumor tissues. Here, we report on a 3-month-old boy with multiple café au lait macules (CAMs) and juvenile myelomonocytic leukemia (JMML) who was found to carry a previously established pathogenic NF1 variant (c.586+5G>A), as revealed by whole-exome sequencing. Surprisingly, however, this variant was detected in the homozygous state in the patient and was absent in the parents and siblings. Deep sequencing of this variant using blood, buccal swabs and skin samples was performed. As expected for an NF1 gene mutation promoting JMML, the variant was detected in 90.6% of the blood DNA reads, in sharp contrast to the mere 5% and 0.74% of reads in the saliva- and skin fibroblast-derived DNA, respectively. Our analysis, therefore, confirmed postzygotic origin of the variant followed by a mitotic event resulting in its homozygosity, although we could not differentiate between the possibilities of a gene conversion and mitotic crossover. Apparently de novo homozygous variants should trigger a careful investigation into mosaicism to achieve accurate interpretation.

Coincidental Expression of Classic Hodgkin Lymphoma and Neurofibromatosis Type I and Literature Review.

Neurofibromatosis Type 1 (NF1) is a genetic disorder with an incidence of 1 in 2600 to 3000 individuals. It is a clinical diagnosis characterized by café-au-lait macules, neurofibromas, and axillary and/or groin freckling. Because of genetic mutations in the NF1 gene affecting the Ras/mitogen-activated protein kinase pathway, there is also risk of associated soft tissue sarcomas and hematologic malignancies. However, reports of classic Hodgkin lymphoma in patients with NF1 are sparse. We report an adolescent with NF1 who developed classic Hodgkin lymphoma. Although there is an unclear association between mutations in the NF1 gene and classic Hodgkin lymphoma, further studies are warranted.

Moyamoya syndrome in a child with Legius syndrome: Introducing a cerebral vasculopathy to the SPRED1 phenotype?

Legius syndrome is a disorder of the RAS and mitogen-activated protein kinase (MAPK) pathway first described in 2007 by Eric Legius, et al., that has been considered a milder phenotype than reported in the RASopathy neurofibromatosis type 1 (NF1). However, with approximately 200 cases reported in the literature, the Legius syndrome phenotype remains to be fully characterized. We report a child who presented with moyamoya syndrome and who has Legius syndrome due to a pathogenic variant in SPRED1. Vascular complications such as moyamoya syndrome have been reported in NF1. However, this association has not been reported in Legius syndrome. This child's case may represent an expansion of the clinical phenotype of Legius syndrome, and further study is needed. We emphasize the importance of obtaining neuroimaging studies in patients with Legius syndrome who present with new neurologic deficits.

Café au lait spots: When and how to pursue their genetic origins.

Café au lait spots are common birthmarks seen sporadically and in association with several genetic syndromes. Dermatologists are often asked to evaluate these birthmarks both by other physicians and by parents. In some cases, it is challenging to know when and how to pursue further evaluation. Diagnostic challenges may come in the form of the appearance of the individual lesions, areas and patterns of cutaneous involvement, and associated features (or lack thereof). In this review, we aim to clarify when and how to evaluate the child with multiple or patterned café au lait spots and to explain some emerging concepts in our understanding of the genetics of these lesions.

Genetic analyses of mosaic neurofibromatosis type 1 with giant café-au-lait macule, plexiform neurofibroma and multiple melanocytic nevi.

Neurofibromatosis type 1 (NF1) is a genodermatosis caused by heterozygous germ line variations in the NF1 gene. A second-hit NF1 aberration results in the formation of café-au-lait macules, cutaneous neurofibroma and plexiform neurofibroma (PNF). Mosaic NF1 (mNF1), caused by a postzygotic NF1 mutation, is characterized by localized or generalized NF1-related manifestations. Although NF1 and mNF1 are associated with pigmentary skin lesions, clinically recognizable melanocytic nevi that developed over PNF have not been reported. Here, we report the first case of multiple melanocytic nevi that developed on a giant café-au-lait macule and PNF. The PNF had biallelic NF1 deletions, a whole deletion of NF1 and a novel intragenic deletion involving exons 25-30. The deletions were not detected in the blood, which resulted in the diagnosis of mNF1. Furthermore, the nevus cells had not only biallelic NF1 deletions but also NRAS Q61R, a common mutation found in congenital melanocytic nevi. These analyses revealed the coexistence of the two different mosaic diseases, mNF1 and congenital melanocytic nevi. For a diagnosis of cases with atypical NF1-like symptoms, genetic analyses using blood and lesional tissues are useful and aid in genetic counseling.

Neurofibromatosis Type 1 with the Development of Pheochromocytoma and Breast Cancer.

A 40-year-old woman presented with a left adrenal incidentaloma. Based on the presence of café-au-lait spots, cutaneous neurofibroma, and family history, she was diagnosed with neurofibromatosis type 1 (NF1). Adrenal incidentaloma screening showed an elevated normetanephrine level; the left adrenal mass showed the uptake of I-123 meta-iodobenzylguanidine. She underwent left adrenalectomy, and pheochromocytoma was diagnosed. One year later, the results of a biopsy of a palpable mass in the left breast suggested invasive ductal carcinoma. The patient underwent neoadjuvant chemotherapy followed by left breast-conserving surgery. We herein report a rare case of an NF1 patient who developed both pheochromocytoma and breast cancer.