Clinical and molecular aspects of Berardinelli–Seip Congenital Lipodystrophy (BSCL)

[Progeroid syndromes : Aging, skin aging, and mechanisms of progeroid syndromes]

Progeroid syndromes (PSs) are characterized by the premature onset of age-related pathologies. PSs display a wide range of heterogeneous pathological symptoms that also manifest during natural aging, including vision and hearing loss, atrophy, hair loss, progressive neurodegeneration, and cardiovascular defects. Recent advances in molecular pathology have led to a better understanding of the underlying mechanisms of these diseases. The genetic mutations underlying PSs are functionally linked to genome maintenance and repair, supporting the causative role of DNA damage accumulation in aging. While some of those genes encode proteins with a direct involvement in a DNA repair machinery, such as nucleotide excision repair (NER), others destabilize the genome by compromising the stability of the nuclear envelope, when lamin A is dysfunctional in Hutchinson-Gilford progeria syndrome (HGPS) or regulate the DNA damage response (DDR) such as the ataxia telangiectasia-mutated (ATM) gene. Understanding the molecular pathology of progeroid diseases is crucial in developing potential treatments to manage and prevent the onset of symptoms. This knowledge provides insight into the underlying mechanisms of premature aging and could lead to improved quality of life for individuals affected by progeroid diseases.

Congenital generalized lipodystrophy in two siblings from Saudi Arabia: A case report

Congenital generalized lipodystrophy type 1 (CGL1) is a very rare autosomal recessive genetic mutation with generalized lipoatrophy and metabolic complications. We report CGL1 in two Saudi female siblings with lipoatrophy, diabetes mellitus, hypertriglyceridemia, steatohepatitis, and acanthosis due to very rare homozygous 1‐acylglycerol‐3‐phosphate O‐acyltransferase β (AGPAT2) genetic variant.

Hereditary severe insulin resistance syndrome: Pathogenesis, pathophysiology, and clinical management

Severe insulin resistance has been linked to some of the most globally prevalent disorders, such as diabetes mellitus, nonalcoholic fatty liver disease, polycystic ovarian syndrome, and hypertension. Hereditary severe insulin resistance syndrome (H-SIRS) is a rare disorder classified into four principal categories: primary insulin receptor defects, lipodystrophies, complex syndromes, and obesity-related H-SIRS. Genes such as INSR, AKT2, TBC1D4, AGPAT2, BSCL2, CAV1, PTRF, LMNA, PPARG, PLIN1, CIDEC, LIPE, PCYT1A, MC4R, LEP, POMC, SH2B1, RECQL2, RECQL3, ALMS1, PCNT, ZMPSTE24, PIK3R1, and POLD1 have been linked to H-SIRS. Its clinical features include insulin resistance, hyperglycemia, hyperandrogenism, severe dyslipidemia, fatty liver, abnormal topography of adipose tissue, and low serum leptin and adiponectin levels. Diagnosis of H-SIRS is based on the presence of typical clinical features associated with the various H-SIRS forms and the identification of mutations in H-SIRS-linked genes by genetic testing. Diet therapy, insulin sensitization, exogenous insulin therapy, and leptin replacement therapy have widely been adopted to manage H-SIRS. The rarity of H-SIRS, its highly variable clinical presentation, refusal to be tested for genetic mutations by patients' family members who are not severely sick, unavailability of genetic testing, and testing expenses contribute to the delayed or underdiagnoses of H-SIRS. Early diagnosis facilitates early management of the condition, which results in improved glycemic control and delayed onset of diabetes and other complications related to severe insulin resistance. The use of updated genetic sequencing technologies is recommended, and long-term studies are required for genotype-phenotype differentiation and formulation of diagnostic and treatment protocols.

Bone Mineral Density in Congenital Generalized Lipodystrophy: The Role of Bone Marrow Tissue, Adipokines, and Insulin Resistance

Congenital Generalized Lipodystrophy (CGL) is a rare syndrome characterized by the almost total absence of subcutaneous adipose tissue due to the inability of storing lipid in adipocytes. Patients present generalized lack of subcutaneous fat and normal to low weight. They evolve with severe metabolic disorders, non-alcoholic fatty liver disease, early cardiac abnormalities, and infectious complications. Although low body weight is a known risk factor for osteoporosis, it has been reported that type 1 and 2 CGL have a tendency of high bone mineral density (BMD). In this review, we discuss the role of bone marrow tissue, adipokines, and insulin resistance in the setting of the normal to high BMD of CGL patients. Data bases from Pubmed and LILACS were searched, and 113 articles published until 10 April 2021 were obtained. Of these, 76 were excluded for not covering the review topic. A manual search for additional literature was performed using the bibliographies of the studies located. The elucidation of the mechanisms responsible for the increase in BMD in this unique model of insulin resistance may contribute to the understanding of the interrelationships between bone, muscle, and adipose tissue in a pathophysiological and therapeutic perspective.

Oil Red-O Positive lipid blobs on peripheral blood film examination in a muscular infant with the diagnosis of Berardinelli-Seip syndrome

Lipodystrophy syndromes can be acquired or hereditary in nature and are characterized by abnormal fat distribution including the inability of the body to develop and sustain healthy adipose tissue. They may be generalized or partial in nature. The congenital generalized form is termed as Berardinelli-Seip syndrome and may occur due to mutations in the AGPAT2 or BSCL2 genes. In this case report, we present an infant diagnosed with type-1 Berardinelli-Seip syndrome due to pathogenic variation in the AGPAT2 gene. Though this type of lipodystrophy is less severe than the type-2 form, the case highlights the early presentation of the condition in infancy with increased frequency of stools and hypertriglyceridemia. In addition, we want to highlight that identification of characteristic physical appearances and recognition of abnormal findings during basic investigations is important, which can guide a clinician in making a correct diagnosis.

SEIPIN overexpression in the liver may alleviate hepatic steatosis by influencing the intracellular calcium level

SEIPIN deficiency leads to a severe lipodystrophic phenotype with loss of fat tissue. Interestingly, SEIPIN knockout in non-adipocytes is reported to promote intracellular triacylglycerol (TG) accumulation. However, the underlying mechanisms remain unclear at present. Here, we have shown that SEIPIN knockdown and overexpression exert opposite effects on hepatic lipometabolism. Our experimental data suggest that depletion of SEIPIN induces an increase in intracellular TG via activation of ER stress while its overexpression triggers a decrease in the intracellular TG content via increasing PGC-1α, which drives increased mitochondrial activity. Adeno-associated virus-mediated SEIPIN overexpression alleviated high fat diet-induced hepatosteatosis in mice. The collective results indicate that the effects of SEIPIN on TG and PGC-1α are dependent on calcium concentrations, signifying regulatory activity on hepatic lipometabolism through alterations in the intracellular calcium level, and support the potential utility of modulating intracellular SEIPIN and calcium levels as novel therapeutic strategies for fatty liver.

Pseudoacromegaly

Individuals with acromegaloid physical appearance or tall stature may be referred to endocrinologists to exclude growth hormone (GH) excess. While some of these subjects could be healthy individuals with normal variants of growth or physical traits, others will have acromegaly or pituitary gigantism, which are, in general, straightforward diagnoses upon assessment of the GH/IGF-1 axis. However, some patients with physical features resembling acromegaly - usually affecting the face and extremities -, or gigantism - accelerated growth/tall stature - will have no abnormalities in the GH axis. This scenario is termed pseudoacromegaly, and its correct diagnosis can be challenging due to the rarity and variability of these conditions, as well as due to significant overlap in their characteristics. In this review we aim to provide a comprehensive overview of pseudoacromegaly conditions, highlighting their similarities and differences with acromegaly and pituitary gigantism, to aid physicians with the diagnosis of patients with pseudoacromegaly.

Experiência de pessoas que vivem com a Síndrome de Berardinelli-Seip no Nordeste brasileiro

Resumo O artigo analisa a experiência de pessoas que vivem com a Síndrome de Berardinelli-Seip no Nordeste brasileiro. Este estudo qualitativo foi desenvolvido com onze interlocutores, sendo nove pessoas vivendo com a síndrome e duas mães. Para coligir as informações, utilizaram-se observação participante, caracterização social e entrevistas semiestruturadas. Os dados foram analisados por meio da técnica de codificação temática. Emergiram duas categorias: (1) ‘o segredo é fechar a boca’: gerenciamento da alimentação na vida cotidiana; e (2) ‘ah, é uma travesti?’ Corpo, gênero e masculinização. Concluiu-se que na experiência dos interlocutores seus agenciamentos e criatividade se traduziram em estratégias para gerenciamento da alimentação que integravam gostos, valores, hábitos, prescrições biomédicas e prazeres envolvidos em situações de comensalidade. No que tange à corporeidade, evidenciou-se que as representações e as experiências com o corpo apresentam desigualdades de gênero, na medida em que a mulher passa a ser alvo privilegiado de estigmas, preconceitos e discriminação na vida adulta.

Congenital Generalized Lipodystrophy Type 2 in a Patient From a High-Prevalence Area

Congenital generalized lipodystrophy (CGL) is a rare autosomal recessive disease characterized by the loss of body fat. The global prevalence of CGL is one in 10 million, and there are four subtypes. The case is presented of a 18-year-old woman from rural area of the north coast of Peru (Piura) with limited access to health services. She was diagnosed with phenotypic CGL at age 7 months. At age 12 years, she was diagnosed with diabetes and had altered liver function tests. She underwent a liver biopsy, which revealed advanced portal fibrosis. The patient stopped attending evaluations for 3 years; subsequently, she was referred to Dos De Mayo Hospital in Lima. Physical examination revealed typical triangular facies, acanthosis nigricans, and hirsutism; little subcutaneous tissue; proximal muscle weakness with stiffness in joints; and clitorimegaly. As of this writing, the patient is waiting to initiate outpatient therapy with a leptin analog. She has physical characteristics of CGL type 2 and a natural progression of the disease that presents cirrhosis caused by nonalcoholic fatty liver disease. She lives in a region of high CGL type 2 prevalence, which, without treatment, has a poor prognosis. Liver failure is the main cause of death. There are barriers for this group of patients to access the best treatment and one purpose of this report is to attract the attention of health institutions to help us treat these patients.

Berardinelli-Seip syndrome in peritoneal dialysis

A case of Berardinelli-Seip syndrome, a congenital generalised lipodystrophy, is reported. Symptoms first appeared when the patient was 20 years old. She showed severe insulin resistance as well as micro- and macro-angiopathic complications, including chronic kidney disease, which required renal replacement therapy with peritoneal dialysis. The patient's clinical course was reviewed since paediatric age (when initial signs of the disease being already evident) to present time. Berardinelli-Seip syndrome is very uncommon, and the present case is particularly rare because it is the only case (at least as reported in the literature) in a patient receiving dialysis.

Berardinelli-Seip congenital lipodystrophy in two siblings

Berardinelli-Seip congenital lipodystrophy (BSCL) is a very rare autosomal recessive disorder characterized by various dermatological and systemic manifestations such as lipoatrophy, hypertriglyceridemia, hepatomegaly, acanthosis nigricans, and acromegaloid features. BSCL type 2 is more common and severe, with onset in the neonatal period or in early infancy. The locus for BSCL2 has been identified on chromosome 11q13. Early recognition and differentiation from other congenital generalized lipodystrophies help in the initiation of appropriate preventive and therapeutic measures such as lifestyle modification and pharmacotherapy that helps postpone the onset of metabolic syndrome. We report BSCL type 2 in two siblings with several cutaneous manifestations like acanthosis nigricans, hypertrichosis, prominent subcutaneous veins, and increased lanugo hair.

Molecular mechanisms underlying fasting modulated liver insulin sensitivity and metabolism in male lipodystrophic Bscl2/Seipin-deficient mice

Bscl2(-/-) mice recapitulate many of the major metabolic manifestations in Berardinelli-Seip congenital lipodystrophy type 2 (BSCL2) individuals, including lipodystrophy, hepatomegly, hepatic steatosis, and insulin resistance. The mechanisms that underlie hepatic steatosis and insulin resistance in Bscl2(-/-) mice are poorly understood. To address this issue, we performed hyperinsulinemic-euglycemic clamp on Bscl2(-/-) and wild-type mice after an overnight (16-h) fast, and found that Bscl2(-/-) actually displayed increased hepatic insulin sensitivity. Interestingly, liver in Bscl2(-/-) mice after a short term (4-h) fast had impaired acute insulin signaling, a defect that disappeared after a 16-hour fast. Notably, fasting-dependent hepatic insulin signaling in Bscl2(-/-) mice was not associated with liver diacylglyceride and ceramide contents, but could be attributable in part to the expression of hepatic insulin signaling receptor and substrates. Meanwhile, increased de novo lipogenesis and decreased β-oxidation led to severe hepatic steatosis in fed or short-fasted Bscl2(-/-) mice whereas liver lipid accumulation and metabolism in Bscl2(-/-) mice was markedly affected by prolonged fasting. Furthermore, mice with liver-specific inactivation of Bscl2 manifested no hepatic steatosis even under high-fat diet, suggesting Bscl2 does not play a cell autonomous role in regulating liver lipid homeostasis. Overall, our results offered new insights into the metabolic adaptations of liver in response to fasting and uncovered a novel fasting-dependent regulation of hepatic insulin signaling in a mouse model of human BSCL2.

Towards a mechanistic understanding of lipodystrophy and seipin functions

CGL (Congenital generalized lipodystrophy) is a genetic disorder characterized by near complete loss of adipose tissue along with increased ectopic fat storage in other organs including liver and muscle. Of the four CGL types, BSCL2 (Berardinelli-Seip Congenital lipodystrophy type 2), resulting from mutations in the BSCL2/seipin gene, exhibits the most severe lipodystrophic phenotype with loss of both metabolic and mechanical adipose depots. The majority of Seipin mutations cause C-terminal truncations, along with a handful of point mutations. Seipin localizes to the ER and is composed of a conserved region including a luminal loop and two transmembrane domains, plus cytosolic N- and C-termini. Animal models deficient in seipin recapitulate the human lipodystrophic phenotype. Cells isolated from seipin knockout mouse models also exhibit impaired adipogenesis. Mechanistically, seipin appears to function as a scaffolding protein to bring together interacting partners essential for lipid metabolism and LD (lipid droplet) formation during adipocyte development. Moreover, cell line and genetic studies indicate that seipin functions in a cell-autonomous manner. Here we will provide a brief overview of the genetic association of the CGLs, and focus on the current understanding of differential contributions of distinct seipin domains to lipid storage and adipogenesis. We will also discuss the roles of seipin-interacting partners, including lipin 1 and 14-3-3β, in mediating seipin-dependent regulation of cellular pathways such as actin cytoskeletal remodelling.

Berardinelli-Seip syndrome type 1 in an Egyptian child

Berardinelli-Seip syndrome type 1 or Berardinelli-Seip congenital lipodystrophy 1 (BSCL1) is a very rare genetic disorder characterized by lipoatrophy, hypertriglyceridemia, hepatomegaly and acromegaloid features. Its prevalence in Egypt is not known. Here, we report case of a 12-year-old Egyptian boy with the clinical, metabolic and molecular genetics manifestations of BSCL1 including overt diabetes mellitus.

A mutation in the c-fos gene associated with congenital generalized lipodystrophy

BACKGROUND

Congenital generalized lipodystrophy (CGL) or Berardinelli-Seip congenital lipodystrophy (BSCL) is a rare genetic syndrome characterized by the absence of adipose tissue. As CGL is thought to be related to malfunctions in adipocyte development, genes involved in the mechanisms of adipocyte biology and maintenance or differentiation of adipocytes, especially transcription factors are candidates. Several genes (BSCL1-4) were found to be associated to the syndrome but not all CGL patients carry mutations in these genes.

METHODS AND RESULTS

In a patient with CGL and insulin resistance we investigated the known candidate genes but the patient did not carry a relevant mutation. Analyses of the insulin activated signal transduction pathways in isolated fibroblasts of the patient revealed a postreceptor defect altering expression of the immediate early gene c-fos. Sequence analyses revealed a novel homozygous point mutation (c.-439, T→A) in the patients' c-fos promoter. The point mutation was located upstream of the well characterized promoter elements in a region with no homology to any known cis-elements. The identified mutation was not detected in a total of n=319 non lipodystrophic probands. In vitro analyses revealed that the mutation facilitates the formation of a novel and specific protein/DNA complex. Using mass spectrometry we identified the proteins of this novel complex. Cellular investigations demonstrate that the wild type c-fos promoter can reconstitute the signaling defect in the patient, excluding further upstream signaling alterations, and vice versa the investigations with the c-fos promoter containing the identified mutation generally reduce basal and inducible c-fos transcription activity. As a consequence of the identified point mutation gene expression including c-Fos targeted genes is significantly altered, shown exemplified in cells of the patient.

CONCLUSION

The immediate-early gene c-fos is one essential transcription factor to initiate adipocyte differentiation. According to the role of c-fos in adipocyte differentiation our findings of a mutation that initiates a repression mechanism at c-fos promoter features the hypothesis that diminished c-fos expression might play a role in CGL by interfering with adipocyte development.

Berardinelli-Seip syndrome: highlight of treatment challenge

Berardinelli-Seip congenital lipodystrophy (BSCL) syndrome is a rare autosomal-recessive disease characterised by lipoatrophy and associated with deregulations of glycidic and lipid metabolism. We report three BSCL cases with its typical clinical picture and complications. Clinically, they all show marked atrophy of adipose tissue, acromegaly, acanthosis nigricans and tall stature. Two cases present attention deficit hyperactivity and developmental learning disorders; another patient has hypertrophic myocardiopathy and polycystic ovary syndrome. In all the cases AGPAT2 was the identified mutation. All the cases present hypertriglyceridemia. One case has developed hyperinsulinism controlled with metformin and another case already has type 2 diabetes with a difficult clinical control. There is no curative treatment and the current treatment options are based only on symptomatic control of the complications. Recently, published studies showed that leptin-replacement therapy appears a promising tool in the metabolic correction of BSCL complications, highlighting the importance of further investigations in BSCL treatment.

[Lipoatrophic diabetes. A therapeutic challenge]

Congenital generalised lipodystrophy is a rare autosomal recessive disorder characterised by a marked deficiency of adipose tissue and usually recognised at birth. This disorder is associated with early development of metabolic complications such as hypertriglyceridemia, hepatic steatosis, and insulin resistance. These complications ultimately lead to fatal events as a consequence of early atherosclerosis, lipoatrophic diabetes and hepatic cirrhosis. The authors report the case of a patient diagnosed, based on clinical and laboratory findings, in the first year of life. The established diagnosis was then confirmed by identifying a mutation in the BSCL2 gene. Because the hypertriglyceridemia and diabetes were refractory to treatment, the authors present this case in order to reflect on the best therapeutic management of this pathology.

[Genetic and metabolic description of five patients with Berardinelli-Seip syndrome]

OBJECTIVE

To report the genetic and metabolic profile of patients with Berardinelli-Seip syndrome (BSCL) followed at Instituto da Criança, HC-FMUSP.

SUBJECTS AND METHODS

Patients with clinical features of BSCL (n = 5), all female, were evaluated through serum levels of glucose, insulin, lipids, leptin, and liver enzymes. Abdominal sonography and DNA analysis were also performed.

RESULTS

Leptin deficiency and hypertriglyceridemia were found in all the patients. Three progressed to diabetes mellitus. Four patients have mutations in AGPAT2 gene and one have a mutation in CAV1 gene.

CONCLUSION

The earliest metabolic abnormalities were hypertriglyceridemia and insulin resistance, culminating in the onset of diabetes at the time of puberty. Mutations in the AGPAT2 gene were the most frequent in our patients.

Description of an AGPAT2 pathologic allelic variant in a 54-year-old Caucasian woman with Berardinelli-Seip syndrome

A 54-year-old Italian female patient was admitted to our Department with the diagnosis of type 2 diabetes poorly controlled with insulin therapy. The patient was born by consanguineous parents (first degree cousins); she had acromegaloid features, diffuse lipoatrophy and muscular pseudo-hypertrophy since childhood. To confirm the clinical hypothesis of congenital generalized lipodystrophy (CGL) or Berardinelli-Seip syndrome, the sequences of AGPAT2 (encoding for 1-acyl-sn-glycerol-3-phosphate acyltransferase beta) and BSCL2 (encoding for seipin) candidate genes were analyzed. DNA analysis showed the presence of a homozygous mutation in exon 3 of the AGPAT2 gene (P112L). This is the first description of a Caucasian subject with CGL who carries the pathologic allelic variant P112L of the AGPAT2 gene.

A Taiwanese boy with congenital generalized lipodystrophy caused by homozygous Ile262fs mutation in the BSCL2 gene

Congenital generalized lipodystrophy (CGL) is a rare autosomal recessive disease that is characterized by a near-complete absence of adipose tissue from birth or early infancy. Mutations in the BSCL2 gene are known to result in CGL2, a more severe phenotype than CGL1, with earlier onset, more extensive fat loss and biochemical changes, more severe intellectual impairment, and more severe cardiomyopathy. We report a 3-month-old Taiwanese boy with initial presentation of a lack of subcutaneous fat, prominent musculature, generalized eruptive xanthomas, and extreme hypertriglyceridemia. Absence of mechanical adipose tissue in the orbits and scalp was revealed by head magnetic resonance imaging. Hepatomegaly was noticed, and histological examination of a liver biopsy specimen suggested severe hepatic steatosis and periportal necrosis. However, echocardiography indicated no sign of cardiomyopathy and he showed no distinct intellectual impairment that interfered with daily life. About 1 year later, abdominal computed tomography revealed enlargement of kidneys. He had a homozygous insertion of a nucleotide, 783insG (Ile262fs mutation), in exon 7 of the BSCL2 gene. We reviewed the genotype of CGL cases from Japan, India, China and Taiwan, and found that BSCL2 is a major causative gene for CGL in Asian.

Marfan syndrome with neonatal progeroid syndrome-like lipodystrophy associated with a novel frameshift mutation at the 3' terminus of the FBN1-gene

We report on a 25-year-old woman with pronounced generalized lipodystrophy and a progeroid aspect since birth, who also had Marfan syndrome (MFS; fulfilling the Ghent criteria) with mild skeletal features, dilated aortic bulb, dural ectasia, bilateral subluxation of the lens, and severe myopia in addition to the severe generalized lipodystrophy. She lacked insulin resistance, hypertriglyceridemia, hepatic steatosis, and diabetes. Mutation analysis in the gene encoding fibrillin 1 (FBN1) revealed a novel de novo heterozygous deletion, c.8155_8156del2 in exon 64. The severe generalized lipodystrophy in this patient with progeroid features has not previously been described in other patients with MFS and FBN1 mutations. We did not find a mutation in genes known to be associated with congenital lipodystrophy (APGAT2, BSCL2, CAV1, PTRF-CAVIN, PPARG, LMNB2) or with Hutchinson-Gilford progeria (ZMPSTE24, LMNA/C). Other progeria syndromes were considered unlikely because premature greying, hypogonadism, and scleroderma-like skin disease were not present. Our patient shows striking similarity to two patients who have been published in this journal by O'Neill et al. [O'Neill et al. (2007); Am J Med Genet Part A 143A:1421-1430] with the diagnosis of neonatal progeroid syndrome (NPS). This condition also known as Wiedemann-Rautenstrauch syndrome is a rare disorder characterized by accelerated aging and lipodystrophy from birth, poor postnatal weight gain, and characteristic facial features. The course is usually progressive with early lethality. However this entity seems heterogeneous. We suggest that our patient and the two similar cases described before represent a new entity, a subgroup of MFS with overlapping features to NPS syndrome.

Monogenic diabetes secondary to congenital lipodystrophy in a 14-year-old Yemeni girl

A 14-year-old female from Yemen presented with intense abdominal pain and headache. She was born at term to distant cousins, developmentally delayed and significantly dysmorphic. Four years ago, she was diagnosed with diabetes mellitus and undiagnosed hepatic, cardiac, genetic, neurologic, endocrine, musculoskeletal, and gastrointestinal disorders. No therapy was prescribed. Admission laboratory data showed blood glucose = 391 mg/dl, hemoglobin A1c= 12.2%, C-peptide = 3.5 ng/ml, insulin = 6.8 uIU/ml, triglyceride =385 mg/dl, and serum leptin <0.5 ng/ml, (1.1-27.5). Chromosome analysis (46, XX) was normal and serology for Glutamic acid Decarboxylase (GAD), hepatitis and HIV were negative. Clinical examination and laboratory data suggested congenital generalized lipodystrophy (CGL, type BSCL-2). This case illustrates that CGL should be in the differential diagnosis for non-obese patients with diabetes and insulin resistance.

A Japanese child with asymptomatic elevation of serum creatine kinase shows PTRF-CAVIN mutation matching with congenital generalized lipodystrophy type 4

Congenital generalized lipodystrophy (CGL), characterized by generalized absence of adipose tissue, has heterogeneous causes. Recently, a novel type of CGL complicated by muscular dystrophy was categorized as CGL4 caused by PTRF-CAVIN deficiency. However, it is unknown whether CGL4 exhibits clinical abnormalities during the infantile period. Here, we describe the youngest Japanese case of CGL4-a Japanese girl with asymptomatic high serum creatine kinase (CK) levels at 3months old. She was referred to our hospital at 5months of age because of her elevated serum CK (2528IU/L). Generalized absence of adipose tissue was first recognized at 2years of age. Mutation analysis of genes known to be responsible for CGL1-3 failed to disclose any abnormalities. Instead, analysis of the PTRF-CAVIN gene encoding PTRF-CAVIN revealed compound heterozygous mutations, one allele contained an insertion (c.696_697insC) and the other allele harbored a novel nonsense mutation (c.512C>A). Our patient had low serum leptin and adiponectin levels and insulin resistance. Pathological studies on biopsied muscle disclosed mild dystrophic change and highly reduced expression of PTRF-CAVIN. It was concluded that our PTRF-CAVIN deficient patient showed not only CGL but also asymptomatic elevation of serum CK because of her mild muscle dystrophic change.