Complex group of diseases characterized bu an increase or loss, partial or total, acquired or familial, of adipose tissue
Adipose tissue hypertrophy can be:
- Total, diffuse and symmetrical (as in common obesity)
- partial or localized, sometimes with an ethnic connotation (steatopygia in some African women)
- Lipoatrophy
- Localized
- Loss of subcutaneous fat
- Usually due to previous inflammation
- May also be seen in areas of pressure (socks)
- Regional and generalized forms → assciated with lipodystrophy syndromes
- Lipodystrophy
- Alteração generalizada ou regional da distribuição da gordura, com lipoatrofia e lipohipertrofia
- “Though the terms lipodystrophy and lipoatrophy are often used interchangeably, lipoatrophy should be used specifically for selective loss of fat, with lipodystrophy implying a redistribution of fat, in part due to a hypertrophic compensation of the non-atrophic fat” - Bolognia
- Abnormal deposition of fat (lipedema)
- Acquired
- Congenital or Familial
Familial Lipodystrophy
- Generalidades
- Meet specific diagnostic criteria
- Some can be treated with recombinant human leptin (metreleptin)
- Generalized lipodystrophy (Berandinelli-Seip)
- AR
- Complete absence of subcutaneous fat
- Cachetic facies, muscular habitus, huge appetite, acanthosis nigricans, hypertrhichosis, hyperhidrosis, heat intolerance
- Other findings: metabolic syndrome, nphropathy, hypertrophic cardiomyopathy, organomegally, pancreatitis secondary to hypertriglyceridemia, mental retardation in some
- Hyperinsulinemia, insulin resistance, hypertriglyceridemia (nowhere for the fat to go, nowhere for the insulin to act on)
- Partial Lipodystrophy (Dunnigan variant)
- Laminin A/C gene
- Normal at birth, symptoms begin at puberty
- Partial Lipodystrophy (Kobberling variant)
- AD
- Onset: puberty
- Very rare, females
- Loss of fat in extremities, with possible spread to the trunk, but sparing the face
- Increased fat: face and neck
- Other clinical features: muscular hypertrophy, double chin, round face
- Other findings: metabolic syndrome, fatty liver disease, pancreatitis, hypertrophic cardiomyopathy, mandibuloacral dyusplasia in some (mandibular/clavicular hypopplasia, disorders of ectoderm)
- Associated with early cardiovascular disease and pancreatitis
Acquired Lipodystrophy
- HIV-associated lipodystrophy
- Associated with protease inhibitors
- Redistribution of adipose tissue
- Peripheral lipoatrophy, particularly in the face, contrasting with central lipohypertrophy
- Steroid induced lipodystrophy
- In Cushing or iatrogenic hypercortisolism
- Lipodematous infiltration of the neck and shoulders
- Macrolipodystrophy
- Rare congenital hypertrophy of a limb or limb segment associated with fatty infiltration
- “Cellulite”
- Gynoid lipodystrophy of the hips, buttocks and thighs, manifested by an “orange peel” appearance
- Generalized lipodystrophy (Lawrence syndrome)
- Mostly females, begins in childhood
- Associated with autoimmune disease (dermatomyositis, Hashimoto’s thyroiditis, Juvenile Idiopathic Arthritis, SLE, Sjogren’s, Vitiligo, Systemic sclerosis) and preceding viral illnesses
- Partial Lipodystrophy (Barraquer-Simons syndrome)
- Mostly females, childhood or adolescence
- Gradual loss of the subcutaneous fat of the face, followed by neck, shoulders, arms, thorax and upper abdomen
- Associated with complement deficiency, membranoproliferative GN and autoimmune disease (Sjogren’s, SLE, thyroid disease, dermatomyositis)