Deep Sequencing and Phenotyping in an Australian Tuberous Sclerosis Complex "No Mutations Identified" Cohort.

Tuberous sclerosis complex (TSC) is a variable multisystem disorder. The "no mutations identified" (NMI) group are reportedly phenotypically milder than those with an identified molecular cause, and often have mosaic or intronic variants not detected by standard sequencing methods. METHODS: We describe the phenotypes in an Australian TSC NMI group (n = 18) and a molecular testing strategy implementable in a diagnostic laboratory. Massively parallel sequencing (MPS) of the whole genomic regions of TSC1 and TSC2 was performed using DNA extracted from multiple tissue samples per participant. RESULTS: Our study showed that the phenotype in TSC NMI individuals can be similar to those with heterozygous, particularly TSC1, variants. Although neurodevelopmental outcomes can be less severe, the number of organ systems involved was similar to the non-mosaic groups. A diagnostic yield of 72% (13/18) was achieved, with the majority (10/13) being mosaic variants and the remainder heterozygous variants missed on previous testing. CONCLUSION: Testing DNA from multiple tissue samples allowed for validation of otherwise discarded low-level mosaic variants and detection of mosaic variants by MPS without excessive cost or the need for specialised techniques. Implementing this approach in a diagnostic setting is viable and allows optimal clinical care of patients with NMI TSC.

Tuberous sclerosis complex: Diagnostic features, surveillance, and therapeutic strategies.

Tuberous sclerosis complex (TSC) is a rare neurocutaneous disorder of mTOR pathway dysregulation resulting from pathogenic variants in the TSC1 or TSC2 genes. Expression of this disorder may involve abnormal tissue growth and dysfunction within the brain, kidneys, heart, lungs, eyes, skin, bones, and teeth. Neurological manifestations can include subependymal giant cell astrocytomas (SEGAs), high rates of infantile spasms, drug-resistant epilepsy, developmental delay, cognitive impairment, autism spectrum disorder, and other neurobehavioral manifestations. Here we review the potential clinical manifestations of TSC by system, recommended diagnostic and surveillance testing, genetic testing, currently available therapeutic options, and considerations for education and social support resources given the unique challenges of this multi-system disorder.

A case report and review of rheumatoid arthritis co-occurring with tuberous sclerosis complex, a rare occurrence.

Rheumatoid arthritis (RA) is a common autoimmune disease. Tuberous sclerosis complex(TSC) is a rare autosomal dominant disorder. We report a case of RA with TSC. The patient was a 46-year-old woman with polyarthritis and cough symptoms, rheumatoid arthritis associated interstitial lung disease (RA-ILD) was initially considered, and after more than 3 months of anti-rheumatic treatment, the patient still had cough, and further examination revealed that the patient had lymphangioleiomyomatosis in the lungs, hepatic and renal angiomyolipomas, multiple subependymal nodules, Vertebral osteosclerotic nodules, as well as facial angiofibromas and periungual fibroma, RA was finally diagnosed with TSC, and everolimus 10mg qd was added to anti-rheumatic therapy for 1 month, and the patient's cough symptoms were relieved.

Development and internal validation of a clinical risk score to predict incident renal and pulmonary tumours in people with tuberous sclerosis complex.

OBJECTIVE: This study aims to develop and internally validate a clinical risk score to predict incident renal angiomyolipoma (AML) and pulmonary lymphangioleiomyomatosis (LAM) in people with tuberous sclerosis complex (TSC). STUDY DESIGN: Data from 2420 participants in the TSC Alliance Natural History Database were leveraged for these analyses. Logistic regression was used to predict AML and LAM development using 10 early-onset clinical manifestations of TSC as potential predictors, in addition to sex and genetic mutation. For our models, we divided AML into three separate outcomes: presence or absence of AML, unilateral or bilateral and whether any are ≥3 cm in diameter. The resulting regression models were turned into clinical risk scores which were then internally validated using bootstrap resampling, measuring discrimination and calibration. RESULTS: The lowest clinical risk scores predicted a risk of AML and LAM of 1% and 0%, while the highest scores predicted a risk of 99% and 73%, respectively. Calibration was excellent for all three AML outcomes and good for LAM. Discrimination ranged from good to strong. C-statistics of 0.84, 0.83, 0.83 and 0.92 were seen for AML, bilateral AML, AML with a lesion≥3 cm and LAM, respectively. CONCLUSION: Our work is an important step towards identifying individuals who could benefit from preventative strategies as well as more versus less frequent screening imaging. We expect that our work will allow for more personalised medicine in people with TSC. External validation of the risk scores will be important to confirm the robustness of our findings.

Multimodal Analysis of the Retinal Manifestations of Tuberous Sclerosis Complex: A Case Series.

BACKGROUND AND OBJECTIVE: We used a multi-modal imaging approach including fundus fluorescein angiography (FFA) to assess the retinal lesions in tuberous sclerosis complex (TSC) and evaluate their correlation with intracranial tuber burden on magnetic resonance imaging (MRI). PATIENTS AND METHODS: Participants with TSC underwent bilateral fundus photography, optical coherence tomography (OCT), infrared (IR) imaging, and FFA. Participants' most recent MRI brain scans were analyzed to determine intracranial tuber load. RESULTS: Nine participants were included. OCT identified all retinal astrocytic hamartoma (RAH) lesions, IR identified 75%, fundus photography identified 63%, and FFA detected just 57%. On FFA, 20% of flat-type hamartomas and all multi-nodular and transitional types were hyperfluorescent. There were significant positive correlations between the quantities of intracranial tubers and all TSC-retinal lesions (r = 0.8, P < 0.01) and all RAH lesions (r = 0.8, P = 0.01). CONCLUSIONS: A multimodal imaging-based approach with fundal photography, IR imaging, and OCT should be used to assess the retina in TSC as it may indicate the intracranial tuber burden. [Ophthalmic Surg Lasers Imaging Retina 2024;55:568-574.].

The extent of kidney involvement in paediatric tuberous sclerosis complex.

BACKGROUND: Tuberous sclerosis (TSC)-associated kidney disease is a leading cause of mortality in adults with TSC. This study aimed to understand TSC features in children, particularly kidney involvement, to inform clinical care for this specific group. METHODS: This retrospective cohort study included all paediatric (< 19 years) TSC cases at a large tertiary paediatric nephrology centre. Relevant data were collected from patients' records, statistical analyses were performed to identify associations between variables, survival probabilities were estimated with Kaplan‒Meier curves, and log-rank tests were conducted to assess survival differences among genetic mutations. RESULTS: A total of 182 children with TSC were included. Among the 145 children with available kidney imaging data, 78.6% (114/145) exhibited kidney lesions. Angiomyolipomas (AMLs) were significantly more prevalent in the TSC2 mutation group (p = 0.018). Children with TSC2 mutations generally had poorer lesion-free survival than those with TSC1 mutations, but this difference was only significant for AMLs (p = 0.030). The change in size of largest AMLs increased with age and doubled in children above 9 years; a similar pattern was observed when stratified by genetic mutation. In contrast, kidney cysts exhibited two peaks: one in children under 5 years (2.31 mm/year) and the second in children between 15-19 years (2.82 mm/year). Chronic kidney disease was observed in 12.3% (10/81) of children, and high-risk AMLs above 3 cm were observed in 9% (13/145). CONCLUSIONS: While TSC kidney disease emerges later in the disease course than neurological features, our findings emphasise the importance of kidney surveillance during childhood, including routine kidney imaging, kidney function, and blood pressure monitoring.

Early Subclinical Status Epilepticus May Contribute to Developmental Delays in Infants With Tuberous Sclerosis Complex.

We present a case of a newborn with a prenatally discovered cardiac rhabdomyoma leading to early genetic diagnosis of tuberous sclerosis complex (TSC). This early diagnosis prompted a presymptomatic electroencephalography (EEG) that revealed subclinical seizures meeting the definition for status epilepticus on day 1 of life. Antiseizure medications (ASMs), including vigabatrin, were started. The EPISTOP and PREVeNT trials demonstrated that early life initiation of vigabatrin may reduce the degree of refractory epilepsy and epileptic spasms (ES) in this population (TSC). Although neonatal seizures are a known entity in TSC, continuous neonatal EEG monitoring is not standard at birth. This case supports early consideration for neonatal EEG monitoring to identify and treat neonatal seizures, reduce risk for infantile spasms, and potentially improve neurodevelopmental outcomes.

Follow-up report of fundus findings of tuberous sclerosis-associated retinal astrocytoma of two siblings.

A late adolescent with tuberous sclerosis (TS) presented with reduced vision in one eye to our tertiary care university hospital 4 years ago. Fundus examination revealed multiple retinal astrocytic hamartomas (RAHs) in both eyes. His younger sibling, who also had TS, was found to have RAH on retinal screening. The swept-source optical coherence tomography (SS-OCT) findings were typical of RAH. We further noted that some of the RAH lesions showed segmental whitening of the outer walls of the arterioles, which traversed through them. The segmental whitening may suggest the enveloping of normal retinal vessels by the tumour. En-face and B-scan SS-OCT angiography of patients with TS showed vascularity within the tumour. The vessels within the tumour appeared to be in continuity with the retinal vasculature. Both siblings were reviewed annually. At the end of 4 years, there was no change in visual acuity, tumour size, number, vascularity and behaviour.

Malignant tumors in tuberous sclerosis complex: a case report and review of the literature.

BACKGROUND: Tuberous sclerosis complex (TSC) is a rare, autosomal dominant genetic disease that arises from TSC1 or TSC2 genetic mutations. These genetic mutations can induce the development of benign tumors in any organ system with significant clinical implications in morbidity and mortality. In rare instances, patients with TSC can have malignant tumors, including renal cell carcinoma (RCC) and pancreatic neuroendocrine tumor (PNET). It is considered a hereditary renal cancer syndrome despite the low incidence of RCC in TSC patients. TSC is typically diagnosed in prenatal and pediatric patients and frequently associated with neurocognitive disorders and seizures, which are often experienced early in life. However, penetrance and expressivity of TSC mutations are highly variable. Herein, we present a case report, with associated literature, to highlight that there exist undiagnosed adult patients with less penetrant features, whose clinical presentation may contain non-classical signs and symptoms, who have pathogenic TSC mutations. CASE PRESENTATION: A 31-year-old female with past medical history of leiomyomas status post myomectomy presented to the emergency department for a hemorrhagic adnexal cyst. Imaging incidentally identified a renal mass suspicious for RCC. Out of concern for hereditary leiomyomatosis and renal cell carcinoma (HLRCC) syndrome, the mass was surgically removed and confirmed as RCC. Discussion with medical genetics ascertained a family history of kidney cancer and nephrectomy procedures and a patient history of ungual fibromas on the toes. Genetic testing for hereditary kidney cancer revealed a 5'UTR deletion in the TSC1 gene, leading to a diagnosis of TSC. Following the diagnosis, dermatology found benign skin findings consistent with TSC. About six months after the incidental finding of RCC, a PNET in the pancreatic body/tail was incidentally found on chest CT imaging, which was removed and determined to be a well-differentiated PNET. Later, a brain MRI revealed two small cortical tubers, one in each frontal lobe, that were asymptomatic; the patient's history and family history did not contain seizures or learning delays. The patient presently shows no evidence of recurrence or metastatic disease, and no additional malignant tumors have been identified. CONCLUSIONS: To our knowledge, this is the first report in the literature of a TSC patient without a history of neurocognitive disorders with RCC and PNET, both independently rare occurrences in TSC. The patient had a strong family history of renal disease, including RCC, and had several other clinical manifestations of TSC, including skin and brain findings. The incidental finding and surgical removal of RCC prompted the genetic evaluation and diagnosis of TSC, leading to a comparably late diagnosis for this patient. Reporting the broad spectrum of disease for TSC, including more malignant phenotypes such as the one seen in our patient, can help healthcare providers better identify patients who need genetic evaluation and additional medical care.

Validation of the Index for Facial Angiofibromas: Data analysis from a randomized controlled trial of sirolimus gel treatment in patients with tuberous sclerosis complex.

The Index for Facial Angiofibromas (IFA), a novel scoring system for angiofibromas, has been validated in patients with tuberous sclerosis complex (TSC). The objective of this analysis was to further validate the IFA using data from a clinical trial of topical sirolimus in patients with TSC. This was an analysis of photographs from a Phase III trial conducted in Japan (NCT02635789). Patients (n = 62) were randomized 1:1 to receive sirolimus or placebo gel for 12 weeks. Changes in angiofibromas were independently assessed using the primary composite endpoint, the Facial Angiofibroma Severity Index (FASI), and the IFA. Thresholds for a clinically meaningful change in IFA score were evaluated using receiver operating characteristic (ROC) analysis. The IFA scores had good-to-excellent inter-assessor reliability, very high intra-assessor reliability, and could be used to evaluate the distribution of disease severity at baseline. High correlations were observed between the categorized change from baseline in IFA scores and the primary composite endpoint (Kendall's coefficient of concordance, W = 0.8655, p < 0.0001), and between the change from baseline in IFA and FASI scores (Kendall's coefficient of concordance, W = 0.745, p < 0.0001). By ROC analysis, an optimal IFA cut-off point of 1.667 was determined to distinguish patients with markedly improved or improved angiofibromas from those with slightly improved or unchanged angiofibromas (area under the curve 0.937) as determined by the primary composite endpoint. The IFA score is potentially clinically useful because of its high validity and reliability. A decrease in score from baseline of ≥1.667 may be considered clinically meaningful.

Measurement of Developmental and Behavioral Concerns in Toddlers With Tuberous Sclerosis Complex.

BACKGROUND: The TAND (Tuberous Sclerosis Complex [TSC]-Associated Neuropsychiatric Disorders) Checklist was developed as a clinical screener for neurodevelopmental disorders in TSC. Most studies have described patterns in older children and adults. This study sought to better understand behavioral concerns as measured by the TAND Checklist in young children with TSC. METHODS: We examined patterns of caregiver responses to the TAND Checklist in 90 toddlers with TSC (12 to 23 months n = 60; 24 to 36 months n = 30) through data collected during baseline visits across two TSC early intervention studies. RESULTS: Over 90% of caregivers reported at least one behavioral concern related to TAND. The number of concerns increased with age. Delayed language was the most frequently reported concern across ages (12 to 23 months: 58.3%, 24 to 36 months: 86.7%). Questions related to behavioral concerns were largely relevant in this age range, but questions in other areas, such as neuropsychological or academic function, were not. CONCLUSIONS: TAND symptoms are very common in toddlers with TSC, and these symptoms may increase with age. The TAND Checklist is a useful tool for identifying behavioral concerns efficiently, but several items and sections are not suited to younger children. Results support the development of an abbreviated form of the TAND Checklist for toddlers.

Dermoscopy of hypopigmented macules unveiling genetic diagnosis of tuberous sclerosis complex type 2 in an infant presenting with sacral chordoma.

A 2-month-old male with surgically resected sacral chordoma presented with multiple hypopigmented macules showing characteristic patchy, sharply demarcated areas of pigment network on dermoscopy. These dermoscopic findings were suggestive of the ash-leaf macules of tuberous sclerosis over other common hypopigmented macules in neonates. Chordomas presenting in early childhood in the sacral location have been reported as a rare manifestation of tuberous sclerosis complex. The combination of these findings led to a diagnosis of tuberous sclerosis, confirmed with the finding of a heterozygous TSC2 gene deletion; treatment with sirolimus resulted in regression of cardiac rhabdomyomas and hypopigmented macules.

A de novo frameshift variant in MED13 gene in a patient with autism spectrum disorder and magnetic resonance imaging abnormalities mimicking tuberous sclerosis.

The mediator complex subunit 13 (MED13) gene is implicated in neurodevelopmental disorders including autism spectrum disorder (ASD), intellectual disability, and speech delay with varying severity and course. Additional, extra central nervous system, features include eye or vision problems, hypotonia, congenital heart abnormalities, and dysmorphisms. We describe a 7-year- and 4-month-old girl evaluated for ASD whose brain magnetic resonance imaging was suggestive of multiple cortical tubers. The exome sequencing (ES - trio analysis) uncovered a unique, de novo, frameshift variant in the MED13 gene (c.4880del, D1627Vfs*17), with a truncating effect on the protein. This case report thus expands the phenotypic spectrum of MED13-related disorders to include brain abnormalities.

Nutritional status as a predictive factor for paediatric tuberous sclerosis complex-associated kidney angiomyolipomas: a retrospective analysis.

The purpose of this study is to determine the predictive factors of tuberous sclerosis complex (TSC)-associated kidney disease and its progression in children. Retrospective review of children with TSC in a tertiary children's hospital was performed. Relevant data were extracted, and Cox proportional hazards regression was used to establish predictors of kidney lesions. Logistic regression was conducted to identify factors predicting chronic kidney disease (CKD) and high-risk angiomyolipomas (above 3 cm). Kidney imaging data were available in 145 children with TSC; of these, 79% (114/145) had abnormal findings. The only significant predictive factor for cyst development was being female (HR = 0.503, 95% CI 0.264-0.956). Being female (HR = 0.505, 95% CI 0.272-0.937) and underweight (HR = 0.092, 95% CI 0.011-0.800) both lowers the risk of having angiomyolipomas, but TSC2 mutations (HR = 2.568, 95% CI 1.101-5.989) and being obese (HR = 2.555, 95%CI 1.243-5.255) increases risks. Ten (12%) of 81 children with kidney function tested demonstrate CKD stages II-V, and only angiomyolipomas above 3 cm predict CKD. Additionally, 13/145 (9%) children had high-risk angiomyolipomas, whereby current age (adjusted odds ratio (aOR) 1.015, 95% CI 1.004-1.026) and being overweight/obese (aOR 7.129, 95% CI 1.940-26.202) were significantly associated with angiomyolipomas above 3 cm. CONCLUSIONS: While gender and genotype are known predictors, this study includes the novel finding of nutritional status as a predictor of TSC-associated kidney disease. This study sheds light on a possible complex interplay of hormonal influences, obesity, and kidney angiomyolipomas growth, and further investigations focusing on the impact of nutritional status on TSC-associated kidney disease are warranted. WHAT IS KNOWN: • Gender and genotype are well-studied predictive factors in TSC kidney disease. WHAT IS NEW: • Nutritional status may influence the development and the progression of kidney lesions in children with TSC and should not be overlooked. • Management guidelines of TSC-associated kidney disease can address nutritional aspects.

Cardiac Rhabdomyomas Presenting with Critical Cardiac Obstruction in Neonates and Infants: Treatment Strategies and Outcome, A Single-Center Experience.

Cardiac rhabdomyomas are the most common benign pediatric heart tumor in infancy, which are commonly associated with tuberous sclerosis complex (TSC). Most rhabdomyomas are asymptomatic and spontaneously regress over time. However, some cases especially in neonates or small infants can present with hemodynamic instability. Surgical resection of the tumor, which has been the gold standard in alleviating obstruction, is not always possible and may be associated with significant morbidity and mortality. Recently, mammalian target of rapamycin inhibitors (mTORi) have been shown to be safe and effective in the treatment of TSC. We present the outcomes of neonates and an infant who received treatment for symptomatic rhabdomyomas at a tertiary cardiology center. Medical records were reviewed to obtain clinical, demographic, and outcome data. Six patients received interventions for symptomatic rhabdomyomas, median age at presentation was 1 day old (range from 1 to 121 days old), and 67% of the patients had a pathogenic mutation in TSC gene. One patient underwent surgical resection of solitary tumor at right ventricular outflow tract (RVOT) successfully. In the four patients with left ventricular outflow tract (LVOT) obstruction, two patients received combined therapy of surgical debulking of LVOT tumor, Stage I palliation procedure, and mTORi and two patients received mTORi therapy. One patient with RVOT obstruction underwent ductal stenting and received synergistic mTORi. Four of the five patients had good response to mTORi demonstrated by the rapid regression of rhabdomyoma size. 83% of patients are still alive at their latest follow-up, at two to eight years of age. One patient died on day 17 post-LVOT tumor resection and Hybrid stage one due to failure of hemostasis, in the background of familial factor VII deficiency. Treatment of symptomatic rhabdomyoma requires individualized treatment strategy based on the underlying pathophysiology, with involvement of multidisciplinary teams. mTORi is effective and safe in inducing rapid regression of rhabdomyomas. A standardized mTORi prescription and monitoring guide will ensure medication safety in neonates and infants with symptomatic cardiac rhabdomyoma. Although the majority of tumors responded to mTORi, some prove to be resistant. Further studies are warranted, ideally involving multiple international centers with a larger number of patients.

Giant cell angiofibroma of gingiva in tuberous sclerosis complex: a case report and literature review.

BACKGROUND: Tuberous sclerosis complex (TSC) is a rare, complex genetic disorder characterized by hamartomas and neoplastic lesions in various organ systems. With the development of radiology and gene testing, the diagnostic criteria for TSC were updated in 2012 at the International Consensus Conference. Intraoral fibromas have long been associated with TSC. However, the incidence of giant cell angiofibroma (GCA) in TSC patients is extremely rare. Here, we report the first case of GCA in the gingival tissue of a patient with TSC. CASE PRESENTATION: A 41-year-old woman first visited the Department of Oral and Maxillofacial Surgery, Chonnam National University Dental Hospital, complaining of gingival enlargement. Clinical examination revealed several manifestations associated with TSC, including intraoral fibromas, facial angiofibromas, dental enamel pits, ungual fibromas, "confetti" skin lesions, hypomelanotic macules, and a shagreen patch. Intraoral examination revealed a 6.0 × 5.0 cm gingival overgrowth on the left mandible. Surgical excision was performed, and subsequent histopathological examination confirmed the diagnosis of GCA. There was no evidence of recurrence within the 24- months of surgery. CONCLUSIONS: We report the first case of GCA in the gingival tissue of a patient with TSC. This report would contribute to an improved understanding of this rare disease. However, further case reports are necessary to clarify the relationship between GCA and TSC.

The Genetics of Tuberous Sclerosis Complex and Related mTORopathies: Current Understanding and Future Directions.

The mechanistic target of rapamycin (mTOR) pathway serves as a master regulator of cell growth, proliferation, and survival. Upregulation of the mTOR pathway has been shown to cause malformations of cortical development, medically refractory epilepsies, and neurodevelopmental disorders, collectively described as mTORopathies. Tuberous sclerosis complex (TSC) serves as the prototypical mTORopathy. Characterized by the development of benign tumors in multiple organs, pathogenic variants in TSC1 or TSC2 disrupt the TSC protein complex, a negative regulator of the mTOR pathway. Variants in critical domains of the TSC complex, especially in the catalytic TSC2 subunit, correlate with increased disease severity. Variants in less crucial exons and non-coding regions, as well as those undetectable with conventional testing, may lead to milder phenotypes. Despite the assumption of complete penetrance, expressivity varies within families, and certain variants delay disease onset with milder neurological effects. Understanding these genotype-phenotype correlations is crucial for effective clinical management. Notably, 15% of patients have no mutation identified by conventional genetic testing, with the majority of cases postulated to be caused by somatic TSC1/TSC2 variants which present complex diagnostic challenges. Advancements in genetic testing, prenatal screening, and precision medicine hold promise for changing the diagnostic and treatment paradigm for TSC and related mTORopathies. Herein, we explore the genetic and molecular mechanisms of TSC and other mTORopathies, emphasizing contemporary genetic methods in understanding and diagnosing the condition.