Diagnosis and treatment of lipodystrophy: a step‑by‑step approach

Aim : Lipodystrophy syndromes are rare heterogeneous disorders characterized by defciency of adipose tissue, usually a decrease in leptin levels and, frequently, severe metabolic abnormalities including diabetes mellitus and dyslipidemia. Purpose : To describe the clinical presentation of known types of lipodystrophy, and suggest specifc steps to recognize, diagnose and treat lipodystrophy in the clinical setting. Methods : Based on literature and in our own experience, we propose a stepwise approach for diagnosis of the diferent subtypes of rare lipodystrophy syndromes, describing its more frequent co-morbidities and establishing the therapeutical approach. Results : Lipodystrophy is classifed as genetic or acquired and by the distribution of fat loss, which can be generalized or partial. Genes associated with many congenital forms of lipodystrophy have been identifed that may assist in diagnosis. Because of its rarity and heterogeneity, lipodystrophy may frequently be unrecognized or misdiagnosed, which is concerning because it is progressive and its complications are potentially life threatening. A basic diagnostic algorithm is proposed. Efective management of lipodystrophy includes lifestyle changes and aggressive, evidence-based treatment of comorbidities. Leptin replacement therapy (metreleptin) has been found to improve metabolic parameters in many patients with lipodystrophy. Metreleptin is approved in the United States as replacement therapy to treat the complications of leptin defciency in patients with congenital or acquired generalized lipodystrophy and has been submitted for approval in Europe. Conclusions : Here, we describe the clinical presentation of known types of lipodystrophy, present an algorithm for diferential diagnosis of lipodystrophy, and suggest specifc steps to recognize and diagnose lipodystrophy in the clinical setting.S

Focus on progressive myoclonic epilepsy in Berardinelli-Seip syndrome

This version of the article has been accepted for publication, after peer review (when applicable) and is subject to Springer Nature’s AM terms of use, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: http://dx.doi.org/10.1007/s10072-020-04780-0S

Effect of β-estradiol on adipogenesis in a 3T3-L1 cell model of prelamin A accumulation

The accumulation of farnesylated prelamin A has been suggested as one of the mechanisms responsible for the loss of fat in type 2 familial partial lipodystrophy due to variants in the LMNA gene. In this rare disease, fat loss appears in women after puberty, affecting sex-hormone-dependent anatomical areas. This study investigated the impact of 17-β-estradiol on adipogenesis in murine preadipocytes subjected to a pharmacologically induced accumulation of farnesylated and non-farnesylated prelamin A. To induce the accumulation of non-farnesylated or farnesylated prelamin A, 3T3-L1 cells were treated with the farnesyltransferase inhibitor 277 or the methyltransferase inhibitor N-acetyl-S-farnesyl-l-cysteine methylester. Subsequently, the cells were induced to undergo adipocyte differentiation in the presence or absence of 17-β-estradiol. Prelamin A accumulation was assessed through immunofluorescence, while real-time PCR and Western blot techniques were used to quantify several adipogenic genes and evaluate protein levels, respectively. The results showed that 17-β-estradiol increased adipogenesis, although the combination of this hormone plus farnesylated prelamin A led to a reduction in the number of mature adipocytes and the expression of the different genes involved in adipogenesis. In conclusion, the influence of farnesylated prelamin A accumulation on adipogenesis manifested only in the presence of estradiol. These in vitro findings suggest a potential mechanism that could explain the characteristic phenotype in women suffering type 2 familial partial lipodystrophyThis research was funded by the Instituto de Salud Carlos III, ISCIII and the European Regional Development Fund, ERDF (grant number PI081449), an intramural grant from the Xunta de Galicia (GPC2014/036, ED341b 2017/19, ED431B 2020/37) and a research grant from the Asociación Española de Familiares y Afectados de Lipodistrofias (AELIP). A.F.-P. receives funding from the Fundación Alfonso Martín EscuderoS

An uncommon association of familial partial lipodystrophy, dilated cardiomyopathy, and conduction system disease

A 46-year-old African American woman presented with severe respiratory distress requiring intubation and was diagnosed with nonischemic cardiomyopathy. She had the typical phenotype of familial partial lipodystrophy 2 (FPLD2). Sequence analysis of LMNA gene showed a heterozygous missense mutation at exon 8 (c.1444C>T) causing amino acid change, p.R482W. She later developed severe coronary artery disease requiring multiple percutaneous coronary interventions and coronary artery bypass surgery. She was later diagnosed with diabetes, primary hyperparathyroidism, and euthyroid multinodular goiter. She had sinus nodal and atrioventricular nodal disease and had an implantable cardioverter defibrillator implantation due to persistent left ventricular dysfunction. The device eroded through the skin few months after implantation and needed a reimplant on the contralateral side. She had atrial flutter requiring ablation. This patient with FPLD2 had most of the reported cardiac complications of FPLD2. This case is presented to improve the awareness of the presentation of this disease among cardiologists and internists.The author(s) received no financial support for the research, authorship, and/or publication of this article.S

Lipodystrophy-associated progeroid syndromes

This version of the article has been accepted for publication, after peer review (when applicable) and is subject to Springer Nature’s AM terms of use, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: http://dx.doi.org/10.1007/s42000-022-00386-7With the exception of HIV-associated lipodystrophy, lipodystrophy syndromes are rare conditions characterized by a lack of adipose tissue, which is not generally recovered. As a consequence, an ectopic deposition of lipids frequently occurs, which usually leads to insulin resistance, atherogenic dyslipidemia, and hepatic steatosis. These disorders include certain accelerated aging syndromes or progeroid syndromes. Even though each of them has unique clinical features, most show common clinical characteristics that affect growth, skin and appendages, adipose tissue, muscle, and bone and, in some of them, life expectancy is reduced. Although the molecular bases of these Mendelian disorders are very diverse and not well known, genomic instability is frequent as a consequence of impairment of nuclear organization, chromatin structure, and DNA repair, as well as epigenetic dysregulation and mitochondrial dysfunction. In this review, the main clinical features of the lipodystrophy-associated progeroid syndromes will be described along with their causes and pathogenic mechanisms, and an attempt will be made to identify which of López-Otín’s hallmarks of aging are present.This work was supported by the Instituto de Salud Carlos III and the European Regional Development Fund (ERDF (grant number PI081449), and an intramural grant from the Xunta de Galicia (GPC2014/036, ED341b 2017/19, ED431B 2020/37). A.F.-P. is a Rio Hortega researcher (ISCIII; CM20/00155). S.S.-I. was awarded a Research Fellowship from the Asociación Española de Familiares y Afectados de Lipodistrofias (AELIP).S

Familial partial lipodystrophy syndromes

Lipodystrophies are a heterogeneous group of rare conditions characterised by the loss of adipose tissue. The most common forms are the familial partial lipodystrophy (FPLD) syndromes, which include a set of disorders, usually autosomal dominant, due to different pathogenetic mechanisms leading to improper fat distribution (loss of fat in the limbs and gluteal region and variable regional fat accumulation). Affected patients are prone to suffering serious morbidity via the development of metabolic complications associated to insulin resistance and an inability to properly store lipids. Although no well-defined diagnostic criteria have been established for lipodystrophy, there are certain clues related to medical history, physical examination and body composition evaluation that may suggest FPLD prior to confirmatory genetic analysis. Its treatment must be fundamentally oriented towards the control of the metabolic abnormalities. In this sense, metreleptin therapy, the newer classes of hypoglycaemic agents and other investigational drugs are showing promising results. This review aims to summarise the current knowledge of FPLD syndromes and to describe their clinical and molecular picture, diagnostic approaches and recent treatment modalities.This study was supported by the Instituto de Salud Carlos III and the European Regional Development Fund, ERDF (Grant No. PI081449), and an intramural grant from the Xunta de Galicia (GPC2014/036, ED341b 2017/19, ED431B 2020/37). A.F.-P. is a Rio Hortega researcher (ISCIII; CM20/00155). S.S.I. was awarded a Research Fellowship, granted by the Asociación Española de Familiares y Afectados de Lipodistrofias (AELIP).S

A de novo heterozygous missense BSCL2 variant in 2 siblings with intractable developmental and epileptic encephalopathy

Purpose: We present the case of 2 siblings with profound refractory epilepsy and neurological regression that began at the ages of 3 and 6 months. Diagnosis remained elusive despite extensive metabolic and genetic workups, including use of a targeted next-generation sequencing panel for epilepsy genes. Methods: Whole-exome sequencing was performed for the 2 siblings and their unaffected parents, in addition to fibroblast cell culture, RNA extraction and reverse-transcription, and cDNA PCR. Brain tissue from one of the siblings was collected post-mortem for neuropathological examination, including histology and immunohistochemistry. Results: Ade novo nucleotide change (c.566 T > A; p.(Met189Lys)) in exon 4 of the BSCL2 gene was detected in the 2 siblings, and confirmed by Sanger sequencing. This variant was absent in the parents and in a third, unaffected sibling. Conclusion: Given thede novo nature of the variant, its absence from public and in-house databases, our in silico pathogenicity predictions, and co-segregation of the variant with the disease phenotype, we believe that this novel variant is associated with the epileptic encephalopathy phenotype of the 2 siblings. Our findings provide the first evidence of an association between a heterozygous BSCL2 variant and developmental and early infantile epileptic encephalopathy. Further functional studies will be needed to elucidate the pathophysiological mechanisms underlying this new BSCL2-associated phenotype.This research was partially funded by the Consellería de Industria, Xunta de Galicia (grant number ED341b 2017/19), and by Fundación Mutua Madrileña (Call 2015). S.S-I is a recipient of a Research Fellowship from the Asociación Española de Familiares y Afectados de Lipodistrofias (AELIP).S

Recombinant human leptin treatment in genetic lipodystrophic syndromes: the long-term Spanish experience

Lipodystrophies are a group of diseases mainly characterized by a loss of adipose tissue and frequently associated with insulin resistance, hypertriglyceridemia, and hepatic steatosis. In uncommon lipodystrophies, these complications frequently are difficult to control with conventional therapeutic approaches. This retrospective study addressed the effectiveness of recombinant methionyl leptin (metreleptin) for improving glucose metabolism, lipid profile, and hepatic steatosis in patients with genetic lipodystrophic syndromes. We studied nine patients (five females and four males) with genetic lipodystrophies [seven with Berardinelli-Seip syndrome, one with atypical progeroid syndrome, and one with type 2 familial partial lipodystrophy (FPLD)]. Six patients were children under age 9 years, and all patients had baseline triglycerides levels >2.26 mmol/L and hepatic steatosis; six had poorly controlled diabetes mellitus. Metreleptin was self-administered subcutaneously daily at a final dose that ranged between 0.05 and 0.24 mg/(kg day) [median: 0.08 mg/(kg day)] according to the body weight. The duration of treatment ranged from 9 months to 5 years, 9 months (median: 3 years). Plasma glucose, hemoglobin A1c (Hb A1c), lipid profile, plasma insulin and leptin, and hepatic enzymes were evaluated at baseline and at least every 6 months. Except for the patient with FPLD, metreleptin replacement significantly improved metabolic control (Hb A1c: from 10.4 to 7.1 %, p < 0.05). Plasma triglycerides were reduced 76 % on average, and hepatic enzymes decreased more than 65 %. This study extends knowledge about metreleptin replacement in genetic lipodystrophies, bearing out its effectiveness for long periods of time.This study was supported by the Instituto de Salud Carlos III and the European Regional Development Fund, FEDER (Grant: PI081449) and Consellería de Industria, Xunta de Galicia (Grant: 10PXIB208013PR). S. Sánchez-Iglesias is a Research Fellow granted by the Asociación Española de Familiares y Afectados de Lipodistrofias (AELIP).S

Autoantibodies against perilipin 1 as a cause of acquired generalized lipodystrophy

Acquired generalized lipodystrophy (AGL) is a rare condition characterized by an altered distribution of adipose tissue and predisposition to develop hepatic steatosis and fibrosis, diabetes, and hypertriglyceridemia. Diagnosis of AGL is based on the observation of generalized fat loss, autoimmunity and lack of family history of lipodystrophy. The pathogenic mechanism of fat destruction remains unknown but evidences suggest an autoimmune origin. Anti-adipocyte antibodies have been previously reported in patients with AGL, although their involvement in the pathogenesis has been poorly studied and the autoantibody target/s remain/s to be identified. Using a combination of immunochemical and cellular studies, we investigated the presence of anti-adipocyte autoantibodies in patients with AGL, acquired partial lipodystrophy, localized lipoatrophy due to intradermic insulin injections or systemic lupus erythematosus. Moreover, the impact of anti-adipocyte autoantibodies from AGL patients was assessed in cultured mouse preadipocytes. Following this approach, we identified anti-perilipin 1 IgG autoantibodies in the serum of patients with autoimmune variety-AGL, but in no other lipodystrophies tested. These autoantibodies altered the ability of perilipin 1 to regulate lipolysis in cultured preadipocytes causing abnormal, significantly elevated basal lipolysis. Our data provide strong support for the conclusion that perilipin 1 autoantibodies are a cause of generalized lipodystrophy in these patientsFC, ML-T, AL-L, and SG were supported by grants PI15- 00255 from Instituto de Salud Carlos III (ISCIII, Ministerio de Economía y Competitividad) and Fondos FEDER, Complemento II-CM network (B2017/BMD3673), Acciones Cooperativas y Complementarias Intramurales (ACCI) from CIBERER (ISCIII), and Fundación SENEFRO. MdMwas supported by Roche Farma SA and Foundation Domingo Martínez. VA was financed by Consejería de Educación, Juventud y Deporte of Comunidad de Madrid and by Fondo Social Europeo (Programa Operativo de Empleo Juvenil, and Iniciativa de Empleo Juvenil (YEI), (PEJ15/BIO/AI/0045). DA-V was supported by the intramural research program of the Xunta de Galicia (Programa de Consolidación e Estructuración de Unidades de Investigación Competitivas, grant ED341b 2017/19), by the Instituto de Salud Carlos III (grant number: PI08-1449) and the European Regional Development Fund, FEDER and by the Asociación Española de Familiares y Afectados de Lipodistrofias (AELIP

Clinical characterisation and comorbidities of acquired generalised lipodystrophy: a 14-year follow-up study

Acquired generalised lipodystrophy (AGL) is a rare disorder characterised by the gradual loss of fat that tends to generalise over time, the origin of which is still not fully clarified. The aim of this study was to offer a detailed description of seven patients with AGL (five women, 33.8 ± 18.6 years of age), evaluated over the last 14 years, in order to augment the knowledge of this disorder. The onset of the phenotype occurred during childhood and adolescence in five cases, and in adulthood in two cases. Three patients reported infections or vaccine administration prior to the development of lipodystrophy, and two subjects reported nodular swelling. The most frequent physical features were phlebomegaly, umbilical protrusion/hernia, and acanthosis nigricans. Skinfolds and body composition analysis showed the generalised absence of fat, with the exception of one patient in whom fat loss was spared in the trunk. The loss of fat in the palms/soles was observed in five subjects. Regarding metabolic comorbidities, throughout follow-up, two patients developed type 1 diabetes and one type 2 diabetes; three also presented hypertriglyceridaemia, one of whom developed acute pancreatitis, and no macrovascular complications were observed. Only one patient showed decreased complement C4. Autoimmunity was present in all cases, and six patients manifested Hashimoto’s thyroiditis, type 1 diabetes, autoimmune hepatitis, and/or celiac disease. Thus, there are certain clinical characteristics of AGL that may be considered important diagnostic criteria to differentiate this disorder from other lipodystrophy subtypesThis study was supported by the Instituto de Salud Carlos III (grant PI22/00514), co-funded by the European Union, and an intramural grant from the Xunta de Galicia, ED431B 2020/37. A.F.-P. receives funding from the Fundación Alfonso Martín Escudero. S.S.-I. was awarded a Research Fellowship, granted by the Asociación Española de Familiares y Afectados de Lipodistrofias (AELIP)S