Eosinophilic solid and cystic renal cell carcinoma (ESC-RCC) is a novel and uncommon type of renal cell carcinoma, which has been recently recognized and introduced as a distinct entity in the WHO 2022 kidney tumor classification. Previously known as \"unclassified RCC\", followed by \"tuberous sclerosis complex (TSC)-associated RCC\", ESC-RCC is now a distinct category of kidney tumor, with its own name, with specific clinical manifestations, and a unique morphological, immunohistochemical and molecular profile. Due to its recent introduction and the limited available data, the diagnosis of ESC-RCC is still a complex challenge, and it is probably frequently misdiagnosed. The secret of diagnosing this tumor lies in the pathologists\' knowledge, and keeping it up to date through research, thereby limiting the use of outdated nomenclature. The aim of our case-based review is to provide a better understanding of this pathology and to enrich the literature with a new case report, which has some particularities compared to the existing cases.

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.
METHODS: 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.

BACKGROUND: Pediatric cystic kidney disease (CyKD) includes conditions characterized by renal cysts. Despite extensive research in this field, there are no reliable genetics or other biomarkers to estimate the phenotypic consequences. Therefore, CyKD in children heavily relies on clinical and diagnostic testing to predict the long-term outcomes.
OBJECTIVE: A retrospective study aimed to provide a concise overview of this condition and analyze real-life data from a single-center pediatric CyKD cohort followed during a 12-year period.
METHODS: Medical records were reviewed for extensive clinical, laboratory, and radiological data, treatment approaches, and long-term outcomes.
RESULTS: During the study period, 112 patients received a diagnosis of pediatric CyKD. Male patients were more involved than female (1:0.93). Fifty-six patients had a multicystic dysplastic kidney; twenty-one of them had an autosomal dominant disorder; fifteen had an isolated renal cyst; ten had been diagnosed with autosomal recessive polycystic kidney disease; three had the tuberous sclerosis complex; two patients each had Bardet-Biedl, Joubert syndrome, and nephronophthisis; and one had been diagnosed with the trisomy 13 condition. Genetic testing was performed in 17.9% of the patients, revealing disease-causing mutations in three-quarters (75.0%) of the tested patients. The most commonly presenting symptoms were abdominal distension (21.4%), abdominal pain (15.2%), and oligohydramnios (12.5%). Recurrent urinary tract infections (UTI) were documented in one-quarter of the patients, while 20.5% of them developed hypertension during the long-term follow-up. Antibiotic prophylaxis and antihypertensive treatment were the most employed therapeutic modalities. Seventeen patients progressed to chronic kidney disease (CKD), with thirteen of them eventually reaching end-stage renal disease (ESRD). The time from the initial detection of cysts on an ultrasound (US) to the onset of CKD across the entire cohort was 59.0 (7.0-31124.0) months, whereas the duration from the detection of cysts on an US to the onset of ESRD across the whole cohort was 127.0 (33.0-141.0) months. The median follow-up duration in the cohort was 3.0 (1.0-7.0) years. The patients who progressed to ESRD had clinical symptoms at the time of initial clinical presentation.
CONCLUSIONS: This study is the first large cohort of patients reported from Croatia. The most common CyKD was the multicystic dysplastic kidney disease. The most common clinical presentation was abdominal distention, abdominal pain, and oliguria. The most common long-term complications were recurrent UTIs, hypertension, CKD, and ESRD.

BACKGROUND: Rett syndrome (RTT) and tuberous sclerosis complex (TSC) are two rare disorders presenting with a range of different epileptic seizures. Seizure management requires careful therapy selection, thereby necessitating development of high-quality treatment guidelines. This targeted literature review (TLR) aimed to characterise country-specific and international treatment guidelines available for pharmacological management of seizures in RTT and TSC.
METHODS: A TLR was performed between 25-Jan and 11-Mar 2021. Manual searches of online rare disease and guideline databases, and websites of national heath technology assessment bodies were conducted for the following countries: Australia, Canada, France, Germany, Israel, Italy, Japan, Spain, Switzerland, UK, and US as defined by pre-specified eligibility criteria. Search terms were developed for each condition and translated into local languages where appropriate. Eligible publications were defined as guidelines/guidance reporting pharmacological management of seizures in patients with RTT and TSC. Guideline development methodology, geographical focus, author information and treatment recommendations were extracted from guidelines. An author map was generated using R version 3.5.1 to visualise extent of collaboration between authors.
RESULTS: 24 total guidelines were included, of which three and six contained only recommendations for RTT and TSC, respectively (some provided recommendations for ≥ 1 condition). Guideline development processes were poorly described (50% [12 guidelines] had unclear/absent literature review methodologies); reported methodologies were variable, including systematic literature reviews (SLRs)/TLRs and varying levels of expert consultation. Most (83% [20/24]) were country-specific, with guideline authors predominantly publishing in contained national groups; four guidelines were classified as \'International,\' linking author groups in the US, UK, Italy and France. High levels of heterogeneity were observed in the availability of treatment recommendations across indications, with 13 and 67 recommendations found for RTT and TSC, respectively. For RTT, all treatment recommendations were positive and sodium valproate had the highest number of positive recommendations (Khwaja, Sahin (2011) Curr Opin Pediatr 23(6):633-9). All TSC treatments (21 medications) received either exclusively negative (National Organization for Rare Disorders (2019)) or positive (Chu-Shore et al. (2010) Epilepsia 51(7):1236-41) recommendations; vigabatrin received the highest number of positive recommendations (Kaur, Christodoulou (2019)).
CONCLUSIONS: This review highlights the need for the development of international high-quality and comprehensive consensus-based guidance for the management of seizures with pharmacological therapy in RTT and TSC.
BACKGROUND: Not applicable.

OBJECTIVE: This study aimed to evaluate the efficacy and safety of six new antiseizure medications (ASMs) for adjunctive treatment in adult patients with focal epilepsy and adolescents with Dravet syndrome (DS), Lennox-Gastaut syndrome (LGS), or tuberous sclerosis complex (TSC).
METHODS: A comprehensive literature search was performed using PubMed, Medline, Embase, and Cochrane library databases from inception to October 13, 2023. We included published studies for a systematic review and a network meta-analysis (NMA). The efficacy and safety were reported in terms of a 50% response rate and dropout rate along with serious adverse events (SAEs). The outcomes were ranked with the surface under the cumulative ranking curve (SUCRA).
RESULTS: Twenty eligible trials with 5516 patients and 21 interventions, including placebo, contributed to the analysis. Included ASMs were brivaracetam (BRV), cenobamate (CBM), cannabidiol (CBD), fenfluramine (FFM), everolimus (ELM), and soticlestat (SLT). The six new ASMs were compared in four different epilepsy subtypes. In focal epilepsy treatment, BRV seemed to be safe [vs placebo, risk ratio (RR) = 0.69, 95 % confidence interval (CI): 0.25-1.91] and effective (vs placebo, RR = 2.18, 95 % CI: 1.25-3.81). In treating focal epilepsy, CBM 300 mg was more effective at a 50 % response rate (SUCRA 91.8 %) compared with BRV and CBD. However, with the increase in dosage, more SAEs (SUCRA 85.6 %) appeared compared with other ASMs. CBD had good efficacy on LGS (SUCRA 88.4) and DS (SUCRA 66.2), but the effect on adult focal epilepsy was not better than that of placebo [vs placebo, RR = 0.83 (0.36-1.93)]. The NMA indicated that the likelihood of the most appropriate intervention (SUCRA 91.2 %) with minimum side effects（SUCRA 12.5 %）for the DS was FFM. Compared with CBD, high exposure to ELM demonstrated a more effective treatment of TSC (SUCRA 89.7 %). More high-quality SLT studies are needed to further evaluate the efficacy and safety. The comparison-adjusted funnel plots of annualized relapse rate and side effects in the included studies revealed no significant funnel plot asymmetry.
CONCLUSIONS: This NMA indicated that the most effective treatment strategy for focal epilepsy, DS, Lennox-Gastaut syndrome, and TSC, respectively, included CBM 300 mg, FFM, CBD, and ELM. However, the aforementioned findings need further confirmation.

Recent advancements in genetic testing have revealed cases of mosaicism, demonstrating the phenomenon may be more common than once thought. Broadly defined, mosaicism describes the presence of two genotypically different cell lineages within the same organism. This can arise from small mutations or errors in chromosome segregation, as early as in gametes, before or after fertilization. Mosaicism is directly responsible for many conditions that present in a wide range of tissues, with the presence of the mutation or genetic abnormality following a tissue-dependent pattern. This makes it possible for patients to test negative for a condition using a standard tissue sample while harboring the variant in a different tissue. Understanding the timing and mechanisms of mosaic conditions will aid in targeted testing that is more appropriate to identify a pathogenic variant. This targeted testing should reduce the length of a patient\'s diagnostic odyssey and provide a better understanding of the chances of passing on their variant to their offspring, thereby allowing for more accurate genetic counseling. We illustrate this phenomenon with two cases: one of Pallister-Killian syndrome and the other of tuberous sclerosis complex. Both patients had increased time to diagnosis because of difficulties in identifying genetic variants in tested tissues. Beyond just increased time to diagnosis, we illustrate that mosaic conditions can present as less severe and more variable than the germline condition and how specific germ layers may be affected by the variant. Knowing which germ layers may be affected by the variant can give clinicians a clue as to which tissues may need to be tested to yield the most accurate result.

An abdominal aortic aneurysm is a rare occurrence in pediatric populations. When present, it is usually associated with an underlying etiology such as a connective tissue disorder, inflammatory process, or noninflammatory medial degeneration. In the present report, we describe the case of a girl with tuberous sclerosis complex who underwent successful emergency open repair of a symptomatic infrarenal abdominal aortic aneurysm and recurrent type IV thoracoabdominal aortic aneurysm.

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder with different initial symptoms and complex clinical manifestations. A 14-year-old female patient presented with persistent fever and severe headache. Medical imaging examinations revealed multiple abnormal intracranial lesions. The patient had previously been misdiagnosed with \"encephalitis and acute disseminated encephalomyelitis\" after visiting numerous hospitals. Eventually, by combing the characteristics of the case and genetic testing results, the patient was diagnosed with TSC accompanied by Mycoplasma pneumoniae infection. The purpose of this case report and literature review is to improve understanding of the clinical diagnosis and treatment of TSC so as to avoid misdiagnosis, missed diagnosis, and overtreatment.

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder that can involve multiple organ systems. Diagnosis is based on independent clinical diagnostic criteria and genetic diagnostic criteria (pathogenic variants on TSC1 and TSC2 genes). To make a definitive diagnosis can be especially difficult in oligosymptomatic or asymptomatic patients and in those patients with genetic variants of uncertain significance (VUS). Early diagnosis and lifelong surveillance are paramount to avoid morbidity and potentially life-threatening complications. To increase diagnostic sensibility, less known manifestations of TSC can be helpful. Herein we show a case in which SBLs were used as a diagnostic clue to help diagnose three generations of oligosymptomatic TSC carrying a VUS in TSC1. SBLs are commonly detected in imaging studies of patients with TSC and have been recently included as a minor clinical diagnostic criterion. Clinicians and radiologists should be aware of their significance as they can be mistaken with osteoblastic metastases.

Distal renal tubular acidosis (RTA) is a common cause of renal stones and nephrocalcinosis in children. Distal RTA can be either acquired or congenital because of a genetic defect. Tuberous sclerosis complex is an autosomal dominant inherited neurocutaneous syndrome with variable renal involvement. We describe a case of a six-year-old boy with tuberous sclerosis complex who developed distal RTA and renal stones.