Approach to Diagnosing a Pediatric Patient With Severe Insulin Resistance in Low- or Middle-income Countries

Diabetes mellitus (DM) in children is most often caused by impaired insulin secretion (type 1 DM). In some children, the underlying mechanism for DM is increased insulin resistance, which can have different underlying causes. While the majority of these children require insulin dosages less than 2.0 U/kg/day to achieve normoglycemia, higher insulin requirements indicate severe insulin resistance. Considering the therapeutic challenges in patients with severe insulin resistance, early diagnosis of the underlying cause is essential in order to consider targeted therapies and to prevent diabetic complications. Although rare, several disorders can attribute to severe insulin resistance in pediatric patients. Most of these disorders are diagnosed through advanced diagnostic tests, which are not commonly available in low- or middle-income countries. Based on a case of DM with severe insulin resistance in a Surinamese adolescent who was later confirmed to have autosomal recessive congenital generalized lipodystrophy, type 1 (Berardinelli-Seip syndrome), we provide a systematic approach to the differential diagnosis and work-up. We show that a thorough review of medical history and physical examination generally provide sufficient information to diagnose a child with insulin-resistant DM correctly, and, therefore, our approach is especially applicable to low- or middle-income countries.

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.

Seipin-linked congenital generalized lipodystrophy type 2: a rare case with multiple lytic and pseudo-osteopoikilosis lesions

Congenital generalized lipodystrophy (CGL), or Berardinelli-Seip syndrome (BSCL), is a part of lipodystrophic syndromes that constitute a heterogeneous group of genetic or acquired generalized or partial body fat loss disorders. It is a rare autosomal recessive disease characterized by a near-absence of adipose tissue from birth or early infancy and severe insulin resistance. CGL is classified as type 1-4, depending on the gene involved, and bone lytic lesion is found frequently in type 1 especially in long bones, but reported to be rare in type 2. Here we report an active lifestyle 25-year-old woman with type 2 CGL showing multiple bone lytic and pseudo-osteopoikilosis lesions in hands and feet. Radiograph bone survey showed no apparent abnormality in pelvic bone or axial skeletons. Bone marrow was completely absent and extra-skeletal general fat loss was also evident in whole-body magnetic resonance imaging sparing the orbital, axial, sole, and palmar regions. Radiographic bone survey is important even for type 2 CGL to find the change of bones to provide direction of preventing excessive overload or activity.