22 Članek prispel / Received 24. 9. 2020 Članek sprejet / Accepted 17. 5. 2022 Abstract Purpose: Tuberous sclerosis is an auto- somal dominant neurocutaneous syndro- me that affects approximately 1/6000– 10,000 people. The clinical presentation varies and is dependent on patient age. Renal manifestations, most often angio- myolipomas, cystic renal disease, and re- nal carcinoma, are present in 48%–80% of patients with tuberous sclerosis. The aim of our study was to determine the clinical characteristics and extent of renal impairment in patients with tuberous sclerosis who were followed at the Univer- sity Medical Centre Maribor. Methods: We reviewed the medical re- cords of patients with tuberous sclerosis (ICD Q85.1) who received care at the University Medical Centre Maribor. The medical history, clinical characteristics, laboratory results, imaging studies, and current treatment were highlighted. In Izvleček Namen: Tuberozna skleroza je avtoso- mno dominantni nevrokutani sindrom, ki prizadene približno 1/6.000–10.000 ljudi. Klinična slika se s starostjo spremi- nja, saj so pri različnih starostih prisotni različni klinični znaki. Ledvična priza- detost je prisotna pri 48–80 %, in sicer v obliki angiomiolipomov, ledvičnih cist ali ledvičnega karcinoma. Namen naše raziskave je bil pregled kliničnih manife- stacij pri bolnikih s tuberozno sklerozo, obravnavanih znotraj Univerzitetnega kliničnega centra (UKC) Maribor v za- dnjih desetih letih, in opredelitev števila tistih, ki imajo ledvično prizadetost. Metode: Pregledali smo kartoteke bol- nikov, ki so vodeni v UKC Maribor z diagnozo tuberozna skleroza (MKB – Q85.1). Iz medicinskih zapisov smo razbrali njihove antropometrične meri- tve, starost ob diagnozi, laboratorijske Ključne besede: tuberozna skleroza, ledvice, angiomiolipomi, ciste ledvic Key words: tuberous sclerosis, kidney, angiomyolipomas, kidney cysts Klinične značilnosti in ledvična prizadetost bolnikov s tuberozno sklerozo v UKC Maribor Clinical manifestations of renal disease in patients with tuberous sclerosis complex at University Medical Centre Maribor Avtor / Author Sonja Golob Jančič1,2, Peter Gradišnik1,2, Andreja Osterc Koprivšek1,2, Albin Gačnik3, Nataša Marčun Varda1,2 Ustanova / Institute 1Univerzitetni klinični center Maribor, Klinika za pediatrijo, Maribor, Slovenija; 2Univerza v Mariboru, Medicinska fakulteta, Katedra za pediatrijo, Maribor, Slovenija; 3Univerzitetni klinični center Maribor, Oddelek za nevrologijo, Maribor, Slovenija; 1University Medical Centre Maribor, Department of Paediatrics, Maribor, Slovenia; 2University of Maribor, Faculty of Medicine, Department of Paediatrics, Maribor, Slovenia; 3University Medical Centre Maribor, Department of neurologic diseases, Maribor, Slovenia; Klinična študija / Clinical study ACTA MEDICO-BIOTECHNICA 2022; 15 (1): 22–28 https://doi.org/10.18690/actabiomed.229, CC BY 4.0 © 2022 University of Maribor, University Press 23 INTRODUCTION Tuberous sclerosis complex (TSC) is a hereditary neurocutaneous syndrome that affects 1/6000–10,000 people. TSC is an autosomal dominant trait and often presents de novo (1). In 85% of patients, TSC is caused by mutations in the TSC1 or TSC2 gene. Currently, TSC–associated renal disease pathogenesis dogma holds that a somatic mutation of the functional copy at the affected TSC locus results in clonal proliferation of cells lacking TSC–mediated regulation of the mammalian target of rapamycin complex 1 (mTORC1) pathway (2). Major features of the disease include tumours of the brain, skin, heart, lungs, and kidneys, seizures, and TSC-associated neuropsychiatric disorders (TANDs), which include autism spectrum disorder and cognitive disability (3). There is no strict genotype- phenotype correlation; however, individuals with TSC2 mutations have more severe disease symptoms (4). Penetrance is approximately 95%, but clinical manifestations vary from minor-to-severe disease and are age-dependent. The Tuberous Sclerosis Complex Consensus Conference (TSCCC) published diagnostic criteria in 1998, which were revised in 2012, followed by publishing surveillance protocols and recommendations for diagnostic evaluation of affected individuals (5,6). The diagnosis of TSC relies on the presence of defined clinical features, each of which has a distinct timing izvide, slikovne preiskave in morebitne rezultate genetskega testiranja ter trenu- tni režim zdravljenja. Rezultati: V naši kohorti je 13 bolni- kov s tuberozno sklerozo, starih od 7 do 71 let, mediana starost je 16 let, pov- prečje 25,2 (14,6; 35,9). 92 % (12) ima kožno simptomatiko, ledvična pri- zadetost je prisotna pri 60 % naših bol- nikov. 46 % ima angiomiolipome, 23 % ledvične ciste. Pomembnejše prizadetosti ledvične funkcije nimajo. Sistemsko te- rapijo z everolimusom prejemata dva bolnika, dva imata predpisan topični everolimus za kožne lezije. Genetsko te- stiranje je bilo opravljeno pri 7 bolnikih, pri 5 je bilo pozitivno. Zaklju~ek: Rezultati potrjujejo pogosto prizadetost ledvic pri bolnikih s tuberozno sklerozo v naši kohorti, prim- erljivo z literaturo. Ker je kohorta sestav- ljena predvsem iz pediatričnih bolnikov, je ledvična funkcija dobra, zdravljenje pa redko nujno. Redno spremljanje in multidisciplinarna obravnava sta ključna za dolgoročno blaginjo bolnikov. addition, the results of genetic analysis were reviewed. Results: Our cohort consisted of 13 patients with tuberous sclerosis (age ran- ge, 7–71 years; median age, 16 years; average age, 25.2 [14.6-35.9] years). Cutaneous pathology was noted in 12 (92%) patients. Renal manifestations were present in 6 (60%) of the patients; 46% had angiomyolipomas and 23% had renal cysts. No significant renal function impairment was demonstrated. Two patients were treated with systemic everolimus and two patients were treated with topical everolimus for skin lesions. Genetic analysis was performed in seven patients, five of whom were positive and two of whom were negative. Conclusion: In agreement with literatu- re reports, our results confirmed that renal impairment frequently occurs in tuberous sclerosis patients; however, because most of our patients were children, renal func- tion was stable and treatment was rarely needed. Regular screening and follow-up evaluations in the multidisciplinary team are essential for good long-term outcomes. Naslov za dopisovanje / Correspondence Asist. Sonja Golob Jančič, dr. med. Klinika za pediatrijo Univerzitetni klinični center Maribor Ljubljanska ulica 5, 2000 Maribor Telefon: +386 23212176 Fax: +386 23312393 E-pošta: sonja.golobjancic@ukc-mb.si Klinična študija / Clinical study ACTA MEDICO-BIOTECHNICA 2022; 15 (1): 22–28 24 of onset. Renal manifestations are the second most significant cause of morbidity and mortality in patients with TSC, and include renal cysts, angiomyolipomas, fat-poor lesions, and malignant tumours (7). For the purpose of comprehensive surveillance, we have a Tuberous Sclerosis Centre in our University Medical Centre, the aim of which is to meet twice annually and discuss patient status and follow-up evaluations. The aim of this study was to define the clinical characteristics of our cohort of patients with tuberous sclerosis and the associated renal impairment. METHODS A retrospective analysis of patients with tuberous sclerosis complex (ICD – Q85.1) was done by reviewing patient files. Our search included 13 patients with TSC who were under medical care in the Departments of Paediatrics and Neurologic Diseases at the University Medical Centre Maribor for the last 10 years. The history, clinical characteristics, including renal manifestations, laboratory tests, and treatments were highlighted. In addition, the results of genetic analysis were reviewed. All patients agreed to anonymized data collection and further analysis. RESULTS Our cohort of patients consisted of paediatric and adult patients (age range, 7-71 years; median age, 16 years; average age, 25.2 years [95% CI, 14.6- 35.9]). Cutaneous manifestations in the form of angiofibromas, fibrous cephalic plaques, or hypomelanotic macules were present in 12 of 13 patients (92.2%). Eleven of 13 patients (84.6%) had neurologic symptoms or psychiatric disorders. Renal manifestations were present in 6 of 10 patients (60%), but three patients had missing ultrasound data. One patient had chronic kidney disease (CKD [stage II]); none of the other 12 patients had renal disease. Eye and heart abnormalities in the form of multiple retinal nodular hamartomas and cardiac rhabdomyomas were diagnosed in 3 of 10 (30%) and 3 of 9 patients (33%), respectively. Systemic everolimus was used in two patients for angiomyolipomas and astrocytomas (one patient each); embolization was performed due to renal haemorrhage in the patient with angiomyolipomas. Topical everolimus was prescribed in two patients for skin lesions. Genetic analysis was performed in seven patients, and was positive in five and negative in two patients (Table 1). This was a retrospective study of medical records, therefore missing data was the main shortcoming of this study. In addition, because TSC is a rare disease, the sample size was small. Not all data are included in the medical records at our centre, such as dental health records. DISCUSSION The diagnosis of TSC is established based on a thorough clinical examination and is supported by selective organ imaging and laboratory testing, including a genetic evaluation (6). Our patient cohort was most often affected by skin manifestations, followed by neurologic manifestations, which is consistent with the literature in which 80%–90% of patients have skin and neurological involvement (8). Indeed, skin and neurologic symptoms are the predominant clinical features and are therefore essential for diagnosis along with a complete medical history and thorough clinical examination. Renal manifestations in TSC occur with a high frequency and a wide range of severity (7). Estimated rates of involvement range from 48%-80% (9,10) with at least two large studies reporting an incidence between 60% and 75% (11,12). Renal manifestations were present in two-thirds of our patients, with slightly fewer angiomyolipomas and renal cysts. A strong association between age, angiomyolipoma size, and CKD has been reported; patients with a higher CKD stage tend to be older and have more advanced angiomyolipomas (12). There were no patients who had undergone a nephrectomy or with end stage renal disease in our cohort, but the median age was low and paediatric patients were predominant. The same explanation accounted for the lack of patients with lymphangioleiomyomatosis in our cohort because Klinična študija / Clinical study ACTA MEDICO-BIOTECHNICA 2022; 15 (1): 22–28 25 Klinična študija / Clinical study ACTA MEDICO-BIOTECHNICA 2022; 15 (1): 22–28 Table 1. Patient characteristics and clinical manifestations of tuberous sclerosis in our patients; ESRD - end stage renal disease, EEG - electroencefalogram. Patient’s characteristics Results Male / Female �Number, %� 6/7, 46.2/53.8 Age (median/ average /min/max/) �years� 16/25.2/7/71 Age when patient is diagnosed with TS (median/min/max) �years� 2 /0.08/16.1 Family history of TSC 1 yes/no �%� 23.1/76.9 Genetic verified disease positive/negative/not done �%� 38.5/15.4/46.1 Cutaneous manifestations Angiofibroma or fibrous cephalic plaques yes/no �%� 69.2/30.8 Hypomelanotic cutaneous macules. yes/no �%� 53.8/46.2 Confetti skin lesion yes/no �%� 0/100 Renal manifestations Renal angiomyolipoma yes/no/ no data �%� 46.1/30.8/23.1 Multiple renal cysts yes/no/ no data �%� 23.1/61.5/15.4 ESRD yes/no �%� 0/100 Nephrectomy yes/no �%� 0/100 Neurological manifestations Subependymal astrocytoma yes/no/ no data �%� 23.1/69.2/7.7 Subependymal nodules yes/no �%� 69.2/30.8 Epileptic seizures verified by EEG yes/no �%� 61.5/38.5 Cognitive disorder yes/no �%� 46.1/53.9 Psychiatric disorder yes/no �%� 30.7/69.3 Cardiac rhabdomyoma yes/no/ no data �%� 23.1/46.1/30.8 Lymphangioleiomyomatosis yes/no �%� 0/100 Multiple retinal nodular hamartomas yes/no/ no data �%� 23.1/53.8/23.1 Intraoral fibroma yes/no �%� 0/100 Nonrenal hamartomas yes/no/ no data �%� 23.1/69.2/7.7 Therapy Everolimus systemic/topical/no �%� 15.4/15.4/69.2 Antiepileptic therapy yes/no �%� 61.5/38.5 Psychiatric therapy yes/no �%� 15.4/84.6 26 Klinična študija / Clinical study ACTA MEDICO-BIOTECHNICA 2022; 15 (1): 22–28 Table 2. Protocol for patient evaluation and follow−up in our University Medical Centre Maribor, summarized from (6) Procedure or investigation Newly diagnosed Surveillance Comments Genetic testing / Offer genetic testing for family counselling or when TSC diagnosis is in question but cannot be clinically confirmed MRI brain Obtain MRI of the brain every 1−3 yr in asymptomatic TSC patients younger than age 25 yr to monitor for new occurrence of SEGA More frequently in big or symptomatic SEGA Neuropsychiatric testing Evaluation for TAND at key developmental time points: infancy (0 −3 yr), preschool (3 −6 yr), pre −middle school (6 −9 yr), adolescence (12 −16 yr), early adulthood (18 −25 yr), and as needed thereafter EEG Obtain routine EEG in individuals with known or suspected seizure activity Prolonged video EEG if needed MRI of the abdomen Every 1 −3 yr, to assess for the progression of angiomyolipoma and renal cystic disease Frequently in older than 11 yr or growing more than 2 cm/yr or >5 lesions Kidney US Once a yr When MRI of abdomen is not available Hypertension screening Once a yr Renal function evaluation Once a yr Pulmonary function testing / Once a yr HRCT of the lungs If symptomatic In all females 18 yr or older Clinical dermatologic inspection Once a yr Panoramic radiographs / By age 7 yr, if not performed Echocardiogram Every 1 −3 yr in asymptomatic paediatric patients until regression of cardiac rhabdomyomas is documented ECG Every 3 −5 yr in asymptomatic patients of all ages to monitor for conduction defects Ophthalmologic evaluation Once a yr yr – year/s, SEGA - subependymal giant cell astrocytoma, TAND - TSC-associated neuropsychiatric disorders, MRI - magnetic resonance imaging, US - ultrasound, HRCT-high-resolution computed tomography, EEG - electroencephalograph, ECG - electrocardiogram 27 it is known to affect women > 18 years of age (13). TAND is a new term that was proposed to describe the interrelated functional and clinical manifestations of brain dysfunction, which is common in patients with TSC, including aggressive behaviours, autism spectrum disorders, intellectual disabilities, psychiatric disorders, neuropsychological deficits, and school and occupational difficulties (14). Although our cohort was relatively young, nearly one-half of the patients already had cognitive or psychiatric manifestations of the disease and 15% were receiving psychiatric therapy. We do not have additional information on the type of disorders. According to the literature, the most common psychiatric disorders observed in association with TSC include neurodevelopmental disorders, such as autism spectrum disorders (25%– 50%) and attention deficit hyperactivity disorder (ADHD; 30%–50%), as well as depressive and anxiety disorders [30%–60%] (14). Nearly one-third of our patients were treated with everolimus (topical and systemic, two patients each) and two-thirds were receiving antiepileptic therapy. Most of the patients in our cohort did not meet the criteria for everolimus treatment, presumably due to their age, and epileptic seizures were mostly controlled with antiepileptic therapy. Genetic testing was performed in greater than one- half of our patients, 15% of whom were negative despite meeting the diagnostic criteria for TSC, which is consistent with the literature (15). Because TSC has most often been diagnosed based on clinical findings until recently, older patients did not have genetic testing performed. Nevertheless, we intend to perform genetic testing if the patients will submit to diagnostic testing in the future, which is not always possible because of their health status. Currently we are following the guidelines of the International Tuberous Sclerosis Complex Consensus Conference in 2012 (ITSCCC2012) to follow our patients with TSC (6). According to the protocol, patients are invited for annual visits depending on their symptoms and receive diagnostic evaluation according to the plan described in Table 2. We provide our specialists with a protocol to ensure consistent follow- up. In addition, we have multidisciplinary teams to discuss patients among the various specialists. CONCLUSION Tuberous sclerosis is a rare disease with symptoms pertaining to different specialities. Renal impairment is an important role in mortality and renal involvement is often present. We confirmed that the incidence of renal impairment in our patients is consistent with the literature, although CKD was not common in our patients due to young age. Klinična študija / Clinical study ACTA MEDICO-BIOTECHNICA 2022; 15 (1): 22–28 REFERENCES 1. Crino PB, Nathanson KL, Henske EP. 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